Analysis of differentially expressed transcripts from planthopper-infested wild rice (Oryza minuta)

A subtracted library was constructed from planthopper-infested wild rice (Oryza minuta) by suppression subtractive hybridization in combination with mirror orientation selection. To screen the differentially expressed transcripts in the library, we applied a cDNA microarray containing 960 random clones in a reverse Northern blot analysis using cDNA probes prepared from the mRNAs of control and planthopper-infested samples. On the basis of the signal intensities and expression ratios obtained from experiments performed in triplicate, we selected 383 clones. The elevated expression levels and overall profiles over time were verified by Northern blot analysis. Although Southern blot analysis showed similar copy numbers of the screened genes in O. minuta and O. sativa, it also revealed that the expression profiles had a different pattern. Functional categorization placed the identified transcripts in the categories of subcellular localization, metabolism, and protein fate. The presence of these expressed sequence tags implies that resistance of O. minuta to insect infestation can be achieved not only by an elevated expression of defense-related genes but also by enhanced metabolic activities.

Gold color in onions (Allium cepa): a natural mutation of the chalcone isomerase gene resulting in a premature stop codon

Unusual gold-colored onions were selected from a F3 family originating from a cross between US-type yellow and Brazilian yellow onions. HPLC analysis showed that the gold onions contained a significantly reduced amount of quercetin, the most abundant flavonoid in onions. This result indicated that an early step in the flavonoid biosynthesis pathway might be abnormal in these onions. The expression of flavonoid synthesis genes isolated from onions was examined in gold onions and compared to that in onions of other colors by RT-PCR. The results showed that all genes were transcribed in gold onions as in red onions. In order to identify any critical mutations in flavonoid synthesis genes encoding enzymes involved in early steps of the pathway, the genomic sequence of chalcone isomerase (CHI) was obtained. A premature stop codon and a subsequent single base-pair addition causing a frameshift were identified in the coding region of the CHI gene in the gold onions. Co-segregation of the mutant allele of the CHI gene and the gold phenotype was investigated in the original F2 segregating population. Genotyping of three color groups (red, yellow and gold) of F2 onions revealed perfect co-segregation of the mutant CHI allele with the gold phenotype. All tested gold F2 onions were homozygous for the mutant CHI allele. This perfect co-segregation implies that the presence of a premature stop codon in the gold CHI gene results in an inactive CHI. Inactivation of CHI results in a block in the flavonoid biosynthesis pathway and the accumulation of chalcone derivatives, including a yellow pigment which might be responsible for the gold color in onions.

Pink (P), a new locus responsible for a pink trait in onions (Allium cepa) resulting from natural mutations of anthocyanidin synthase

A new locus conditioning a pink trait in onions was identified. Unusual pink onions were found in haploid populations induced from an F(1) hybrid between yellow and dark red parents and in F(3) populations originating from the same cross. Segregation ratios of red to pink in F(2), backcross, and F(3) populations indicated that this pink trait is determined by a single recessive locus. RT-PCR was carried out to look for any differential expression of anthocyanin synthesis genes between dark red and pink F(3) lines. The transcript level of anthocyanidin synthase (ANS) was significantly reduced in the pink line. To determine whether this reduced transcription is caused by other regulatory factors or by mutations in the ANS gene itself, ANS gene sequences from both dark red and pink F(3) lines were compared to detect any polymorphisms. Polymorphisms were identified, and subsequently utilized as molecular markers for the selection of ANS alleles. Absolute co-segregation of the pink allele and the ANS allele from the pink line was observed in parents, F(1) and F(3) populations. These results indicate that reduced transcription of the ANS gene caused by mutations in a cis -acting element is likely to result in the pink trait in onions.

Semiautomatic segmentation of the cochlea using real-time volume rendering and regional adaptive snake modeling

The human cochlea in the inner ear is the organ of hearing. Segmentation is a prerequisite step for 3-dimensional modeling and analysis of the cochlea. It may have uses in the clinical practice of otolaryngology and neuroradiology, as well as for cochlear implant research. In this report, an interactive, semiautomatic, coarse-to-fine segmentation approach is developed on a personal computer with a real-time volume rendering board. In the coarse segmentation, parameters, including the intensity range and the volume of interest, are defined to roughly segment the cochlea through user interaction. In the fine segmentation, a regional adaptive snake model designed as a refining operator separates the cochlea from other anatomic structures. The combination of the image information and expert knowledge enables the deformation of the regional adaptive snake effectively to the cochlear boundary, whereas the real-time volume rendering provides users with direct 3-dimensional visual feedback to modify intermediate parameters and finalize the segmentation. The performance is tested using spiral computed tomography (CT) images of the temporal bone and compared with the seed point region growing with manual modification of the commercial Analyze software. Our method represents an optimal balance between the efficiency of automatic algorithm and the accuracy of manual work.

Incomplete pancreas divisum: is it merely a normal anatomic variant without clinical implications?

BACKGROUND AND STUDY AIMS

Incomplete pancreas divisum (PD) has been generally regarded as merely a normal anatomic variant, without clinical implications. This study compares the prevalence, symptom occurrence rate, clinical presentation, and outcomes of endoscopic treatment in patients with incomplete PD and those with complete PD.

PATIENTS AND METHODS

The study population consisted of 56 patients (27 with complete PD and 29 with incomplete PD), identified from 4473 newly performed endoscopic retrograde cholangiopancreatography examinations. Endoscopic treatment (minor papilla sphincterotomy with stents or nasopancreatic drainage tube insertion) was attempted in 25 symptomatic patients with PD, which was suspected to be causing the associated pancreatic diseases: acute recurrent pancreatitis (ARP) (n = 13; five patients with complete PD and eight with incomplete PD); chronic pancreatitis (CP) (n = 10: five patients with complete PD and five with incomplete PD); and pancreatic-type pain (PP) (n = 2; one patient with complete PD and one with incomplete PD). The mean follow-up period was 17 months (range 9 - 49 months).

RESULTS

In 12 of the 27 patients with complete PD--six with ARP, five with CP, and one with PP--it was suspected that PD was the cause of pancreatic disease. Ten of the 11 symptomatic patients with complete PD underwent successful endoscopic treatment (five with endoscopic minor papilla sphincterotomy and stenting, and five with endoscopic minor papilla sphincterotomy and endoscopic nasopancreatic drainage), and seven of these ten patients benefited from the endoscopic treatment. In 14 of the 29 patients with incomplete PD--eight with ARP, five with CP, and one with PP--it was suspected that pancreas divisum was the cause of pancreatic disease. Thirteen of the 14 symptomatic patients with incomplete PD underwent successful endoscopic treatments (six with endoscopic minor papilla sphincterotomy and stenting, and seven with endoscopic minor papilla sphincterotomy and endoscopic nasopancreatic drainage), and eight of these 13 patients experienced clinical improvement.

CONCLUSIONS

The prevalence rate, symptom occurrence rate, clinical presentation, and outcomes of endoscopic treatment were similar in patients with complete PD and incomplete PD. Incomplete PD may therefore have similar clinical implications to those of complete PD.

Risk factors for recurrence of primary bile duct stones after endoscopic biliary sphincterotomy

BACKGROUND

Endoscopic biliary sphincterotomy (EST) is a well-established procedure for bile duct stone extraction. Bile duct stones can be classified as primary or secondary. However, few data are available on the recurrence of primary and secondary bile duct stones after EST. Therefore risk factors for the recurrence of primary bile duct stones after EST were prospectively studied.

METHODS

Between 1991 and 1997, 61 patients underwent EST for primary bile duct stones. All met the following criteria: (1) previous cholecystectomy without bile duct exploration, (2) detection of bile duct stones at least 2 years after initial cholecystectomy. Mean follow-up was 2.2 years. Fourteen patients were lost to follow-up. The recurrence of primary bile duct stones was defined as the detection of bile duct stones no sooner than 6 months after complete clearance of primary bile duct stones.

RESULTS

The overall recurrence rate of primary bile duct stones was 21% (10 of 47). Two significant risk factors for recurrence were identified by multivariate analysis: (1) patients with a bile duct diameter of 13 mm or greater after stone removal had recurrences more frequently than those with a duct diameter of 13 mm or less, and (2) patients whose papilla was located on the inner rim or deep within a diverticulum, so that the papillary orifice was not visible endoscopically, had more frequent recurrences than patients with a papilla outside the diverticulum, or no peripapillary diverticulum.

CONCLUSION

The independent risk factors for recurrence of primary bile duct stones were sustained dilation of the bile duct even after complete removal of stones and location of the papilla on the inner rim or deep within a diverticulum.

Szygium aromaticum (L.) Merr. Et Perry (Myrtaceae) flower bud induces apoptosis of p815 mastocytoma cell line

This study was conducted to investigate SAFB-induced apoptosis of mast cells as it pertains to both its basic drug mechanism and the potential therapeutics of the pathologic conditions accompanying mast cell proliferation. SAFB induced many apoptotic manifestations as evidenced by changes in cell morphology, generation of DNA fragmentation, activation of caspase 3, and DNA hypoploidy. The reduction of mitochondrial membrane potential and the release of cytochrome c to cytosol were also demonstrated. However, reduction of mitochondrial membrane potential and cytochrome c release were not prevented by caspase inhibitor zVAD-fmk or PTP blockers such as bongkrekic acid and cyclosporin A. Expression levels of Bcl-2 and Fas remained unchanged following SAFB treatment. This results suggest that the clinical effect of SAFB may depend on the pharmacological mechanism regulating the demise of mast cells.

Synthetic bile acid derivatives induce nonapoptotic death of human retinal pigment epithelial cells

PURPOSE

To study whether the synthetic ursodeoxycholic acid (UDCA) and chenodeoxycholic acid (CDCA) derivatives, which we have synthesized and have reported their apoptosis-inducing effect, have the effect on the proliferation of retinal pigment epithelial cells.

METHODS

UDCA, CDCA, and their synthetic derivatives were administered in culture to the human retinal pigment cell line, ARPE-19. The effect on cell viability and growth was assessed by trypan blue dye exclusion. In order to evaluate the type of cell death, mitochondrial membrane potential assay, DNA electrophoresis, TUNEL assay, nuclear staining and Western blotting for caspase-3 and poly(ADP-ribose) polymerase (PARP) activities were conducted.

RESULTS

Unlike UDCA and CDCA, which did not exhibit a significant effect on viability, their synthetic derivatives decreased the viability of ARPE-19 cells in a concentration-dependent manner. The cells treated with the synthetic derivatives did not demonstrate the characteristic findings of apoptosis, such as DNA ladder, DNA fragmentation, nuclear condensation or fragmentation, and caspase-3 and PARP activation. The reduction of mitochondrial membrane potential was shown. In electron microscopical study nuclear condensation was not shown.

CONCLUSIONS

The synthetic UDCA and CDCA derivatives induced nonapoptotic death of ARPE-19 cells.

Gentamicin decreases the abundance of aquaporin water channels in rat kidney

The present study was performed to examine whether the gentamicin-induced urinary concentration defect is related to an altered regulation of aquaporin (AQP) water channels in the kidney. Male Sprague-Dawley rats were subcutaneously injected with gentamicin (20, 50 or 100 mg/kg per day) for 6 days. The protein expression of AQP1-3 channels and the catalytic activity of adenylyl cyclase were determined in the kidney. Gentamicin treatment resulted in renal failure associated with decreased tubular free water reabsorption and increased urinary flow rate. The expression of AQP2 proteins was significantly decreased in the kidney, in which the cortex was most susceptible, followed by the outer medulla and inner medulla in order. Gentamicin treatment also decreased the shuttling of AQP2, as evidenced by a decrease of its expression in the membrane fraction in proportion to that in the cytoplasmic fraction. The protein expression of AQP1 as well as that of AQP3 was also decreased in the cortex by treatment with the highest dose of gentamicin. The cAMP generation in response to arginine vasopressin or sodium fluoride was decreased by gentamicin, while that to forskolin was not significantly altered. These findings suggest that the primary impairment in the pathway leading to the generation of cAMP lies at the level of G proteins, resulting in a decreased expression of cAMP-mediated AQP channels. The gentamicin-induced urinary concentration defect may in part be accounted for by a reduced abundance of AQP water channels in the kidney.

Characterization of primary pure cholesterol hepatolithiasis: cholangioscopic and selective cholangiographic findings

BACKGROUND

Primary pure cholesterol hepatolithiasis has been described recently. The aim of this study was to analyze its clinical and radiologic features, focusing on the cholangioscopic and selective cholangiographic findings.

METHODS

Primary pure cholesterol hepatolithiasis was identified in 3% (6 of 172) of patients who were treated with cholangioscopic stone removal for primary hepatolithiasis during the study period from 1995 to 1999. These 6 consecutive patients (M/F 5:1, mean age 40 years) were enrolled in the study. They underwent abdominal US, CT, endoscopic retrograde cholangiography (ERC), and percutaneous transhepatic cholangioscopy (PTCS). After confirming that the stones were of the cholesterol type, cholangioscopic stone removal via the percutaneous transhepatic route was performed. For the prevention of recurrence, ursodeoxycholic acid (10 mg/kg/day) was prescribed during follow-up.

RESULTS

US demonstrated high echogenicity with strong shadowing in dilated peripheral ducts, whereas CT failed to demonstrate any intraductal abnormal density or calcification except localized duct dilatation. PTCS demonstrated multiple, white to yellowish stones that were morphologically readily distinguishable from brown pigment intrahepatic stones. In all patients, selective cholangiography disclosed the ductal abnormalities, which could not be delineated by ERC in 4 patients. Complete stone removal by PTCS was achieved in 5 of 6 patients. During follow-up (12 to 49 months, mean 22 months), they were asymptomatic and stone recurrence was not detected by US.

CONCLUSIONS

Primary pure cholesterol hepatolithiasis is distinguishable from the more common brown pigment hepatolithiasis by its cholangioscopic and selective cholangiographic characteristics.

Percutaneous transhepatic cholangioscopic treatment for hepatolithiasis: an evaluation of long-term results and risk factors for recurrence

BACKGROUND

Percutaneous transhepatic cholangioscopy (PTCS) has a major role in the treatment of hepatolithiasis. The aims of this study were to evaluate immediate and long-term results of PTCS treatment and to elucidate the risk factors for recurrence of stones or cholangitis.

METHODS

A retrospective study was conducted of patients with hepatolithiasis who underwent PTCS treatment. A total of 92 patients underwent PTCS treatment and 68 were followed for 24 to 60 months (median 42 months).

RESULTS

Complete clearance of stones was achieved in 74 (80%) patients. The rate of complete clearance was significantly lower in patients with severe intrahepatic strictures compared with that for those with no strictures (14 of 24, 58% vs. 16 of 16, 100%, p < 0.01) and those with mild to moderate strictures (14 of 24, 58% vs. 44 of 52, 85%, p < 0.05). Patients with severe intrahepatic strictures had a higher recurrence rate than those with no or mild strictures (100% vs. 28%, p < 0.01). In addition the recurrence rate in patients with advanced biliary cirrhosis (Child's class B or C) was higher than in those with no or mild (Child's class A) cirrhosis (89% vs. 29%, p < 0.01). In patients with type I and II hepatolithiasis (Tsunoda classification), stones recurred in 2 (12%) patients at 28 and 32 months after successful stone removal, without further recurrence afterwards. The recurrence rate in patients with type III and IV hepatolithiasis increased gradually up to 50% at 60 months of follow-up.

CONCLUSIONS

Severe intrahepatic stricture was the only factor that affected the immediate success rate of PTCS in the treatment of hepatolithiasis. Several risk factors including severe biliary stricture, advanced biliary cirrhosis and Tsunoda type III and IV affected the long-term results.

Electroacupuncture may relax the sphincter of Oddi in humans

BACKGROUND

This study was designed to evaluate the effects of electroacupuncture on sphincter of Oddi (SO) motility in humans and to associate the manometric findings with cholecystokinin (CCK) plasma levels.

METHODS

Eleven patients (M:F = 5:6) with various kinds of biliary disorders were enrolled. SO motility was monitored with conventional low-compliance, continuous perfusion technique at ERCP (n = 9) or via percutaneous transhepatic cholangioscopy (n = 2). After baseline monitoring for phasic wave contractions of SO, electroacupuncture was applied at a specific acupoint GB 34. A nonspecific acupoint 5 cm away from GB 34 was selected as a control. Manometric parameters of the SO were also measured in 6 subjects during stimulation of the control acupoint. CCK plasma levels were measured during electroacupuncture stimulation.

RESULTS

All manometric parameters including basal pressure, amplitude, frequency, and duration of phasic wave contractions of the SO were significantly decreased (p < 0.05) during electroacupuncture stimulation. The inhibition of SO contractility was accompanied by increased CCK plasma levels. After discontinuation of electroacupuncture stimulation, restoration of amplitude and duration to basal conditions was noted. A tendency toward return of SO basal pressure and contractile frequency to baseline was also observed. Stimulation of the control acupoint did not affect SO contractility.

CONCLUSION

Electroacupuncture stimulation of acupoint GB 34 resulted in reversible inhibition of SO contraction in humans. The response of SO to electroacupuncture stimulation may be mediated by some neurohormonal mechanisms including CCK release.

Tumor vessel: a valuable cholangioscopic clue of malignant biliary stricture

BACKGROUND

An irregularly dilated and tortuous vessel, the so-called tumor vessel, is considered to be one of the cholangioscopic features that suggest biliary malignancy. This is a prospective analysis of the presence of a tumor vessel as a finding that discriminates between benign and malignant biliary strictures.

METHODS

From August 1997 to August 1998, a total of 63 patients with biliary strictures diagnosed with endoscopic retrograde cholangiography or percutaneous transhepatic cholangiography obtained during percutaneous transhepatic biliary drainage tube placement were included in this study. Strictures were characterized as benign or malignant based on the observation of tumor vessels. The results were compared with those of percutaneous transhepatic cholangiography-guided biopsy and final diagnosis.

RESULTS

Forty-one patients were confirmed to have malignant strictures and 22 had benign biliary strictures. Cancer was confirmed by histopathologic evaluation of biopsies in 33 of 41 patients with malignancy (80.4%). Tumor vessel was seen in 25 of 41 patients with malignancy (61%). No patients with benign stricture had tumor vessels. Of the 8 patients with negative percutaneous transhepatic cholangioscopy-guided biopsies but with a final diagnosis of malignancy, 6 had tumor vessels. Combining the observation of tumor vessel and percutaneous transhepatic cholangiography-guided biopsy resulted in a diagnosis of malignancy in 39 of 41 patients (96%) and significantly increased the rate of preoperative diagnosis when compared with percutaneous transhepatic cholangiography-guided biopsy or presence of tumor vessel alone (p<0.05).

CONCLUSION

The presence of tumor vessel may be a valuable cholangioscopic finding that indicates the presence of a malignant biliary stricture. The combination of tumor vessel observation and percutaneous transhepatic cholangiography-guided biopsy may improve the preoperative diagnosis of malignancy.

Safety and usefulness of percutaneous transhepatic cholecystoscopy examination in high-risk surgical patients with acute cholecystitis

BACKGROUND

The aim of the present study was to evaluate the diagnostic and therapeutic usefulness of percutaneous transhepatic cholecystoscopy in high-risk surgical patients with acute cholecystitis.

METHODS

Between January 1992 and June 1998, there were 33 consecutive patients who underwent percutaneous transhepatic cholecystostomy and subsequent percutaneous transhepatic cholecystoscopy for the management of acute cholecystitis.

RESULTS

Percutaneous transhepatic cholecystostomy and subsequent percutaneous transhepatic cholecystoscopy were successfully accomplished in all 33 patients. During percutaneous transhepatic cholecystoscopy, minor complications (2 episodes of minor bleeding during electrohydraulic lithotripsy, 2 of tube dislodgement, and 1 of bile leakage to peritoneum) occurred in 5 patients. Percutaneous transhepatic cholecystoscopy revealed gallstones in 26 cases, sludge ball in 3, gallbladder carcinoma in 3, and 1 case of clonorchiasis related with acute cholecystitis. The 3 gallbladder cancers which were not identified radiologically were found incidentally during percutaneous transhepatic cholecystoscopy. For the 26 patients with gallstones, percutaneous transhepatic cholecystoscopy and concomitant stone removal were successful in 1 to 4 consecutive sessions (mean 2.2 sessions). Gallstones recurred in 3 of 22 patients (14%) during the mean follow-up period of 27 months. All of them remain asymptomatic.

CONCLUSION

Percutaneous transhepatic cholecystostomy may be justified in the management of acute cholecystitis in selected patients with high surgical risk.

Cholangioscopic findings in bile duct tumors

BACKGROUND

Cholangioscopy has been used in the treatment of bile duct stones and the diagnosis of various bile duct tumors. However, the cholangioscopic characteristics of the various types of bile duct tumors have not been clearly described. We analyzed the results of cholangioscopic examinations and classified the findings according to tumor histology.

METHODS

Cholangioscopic findings from 111 patients with benign or malignant bile duct tumors were reviewed. The mucosal changes, the presence of neovascularization, and the patterns of luminal narrowing were analyzed and compared with the histologic diagnosis.

RESULTS

Bile duct adenocarcinoma can be classified into 3 different types according to the cholangioscopic findings: nodular, papillary, and infiltrative. Bile duct adenoma, hepatocellular carcinoma and other types of bile duct cancer such as mucin-hypersecreting cholangiocarcinoma, biliary cystadenocarcinoma, and squamous cell carcinoma also presented unique cholangioscopic characteristics.

CONCLUSIONS

Bile duct tumors exhibit characteristic cholangioscopic findings and cholangioscopy seems to be useful for differential diagnosis.

A new strategy to predict the neoplastic polyps of the gallbladder based on a scoring system using EUS

BACKGROUND

A new method to predict neoplastic polyps of the gallbladder using a scoring system based on five endoscopic ultrasonography (EUS) variables is presented.

METHODS

EUS data from patients with gallbladder polyps who were to undergo cholecystectomy were used for the construction of an EUS scoring system in polyps between 5 and 15 mm in diameter (reference group). The EUS scoring system developed from those patients was applied to other patients (validation group).

RESULTS

In the reference group, size was the most significant predictor of neoplastic polyp. All polyps 5 mm or less in diameter were non-neoplastic and 94% of polyps of greater than 15 mm were neoplastic in the reference group. For polyps between 5 and 15 mm in diameter, the area under the receiver-operating characteristic curves (ROC) plots for the endoscopic scoring system was significantly greater than that under the ROC plots for polyp size alone (p < 0.01). In the validation group, the risk of neoplastic polyp was significantly higher for polyps with a score of 6 or greater compared with those with a score of less than 6 (p < 0.01).

CONCLUSIONS

Our data show that a score based on five EUS variables identifies those patients at risk of neoplasia when polyps are between 5 and 15 mm in diameter. (Gastrointest Endosc 2000;52:372-9).

Absence of thyroid stunning after diagnostic whole-body scanning with 185 MBq 131I

There has been recent controversy regarding the optimal protocol for imaging and ablation of post-thyroidectomy patients. Several authors have suggested that a scanning dose of 185-370 MBq (5-10 mCi) (131)I may be capable of producing a stunning effect on thyroid tissue that may interfere with the uptake and efficacy of the subsequent ablation dose of radioiodine. The purpose of this study was to determine whether a 185-MBq (5 mCi) diagnostic dose of (131)I produces a visually apparent stunning effect 72 h before (131)I ablation therapy.

METHODS

One hundred twenty-two consecutive post-thyroidectomy patients for differentiated thyroid carcinoma received a 185-MBq (5 mCi) diagnostic dose of (131)I followed by a whole-body diagnostic scan at 72 h. On the same day the diagnostic scan was completed, the patient was admitted to the hospital and received an (131)I ablation therapy dose of 5550 MBq (150 mCi) in most cases. A postablation, whole-body scan was obtained at 72 h and compared with the previous diagnostic scan for any visual evidence of stunning.

RESULTS

No cases of visually apparent thyroid stunning were observed on any of the postablation scans with regard to the number of (131)I foci identified or the relative intensity of (131)I uptake seen.

CONCLUSION

Diagnostic whole-body scanning can be performed effectively with a 185-MBq (5 mCi) dose of (131)I 72 h before radioiodine ablation without concern for thyroid stunning.

Detection of Helicobacter pylori DNA in human biliary tree and its association with hepatolithiasis

Recently, several authors have reported that Helicobacter pylori DNA has been found in human bile. The aim of this study is to investigate the presence of H. pylori in the biliary tree of Koreans, including the bile, biliary epithelium, and gallstones. This study analyzed intrahepatic bile, bile duct tissue, and gallstones from 43 patients with hepatobiliary disease (PTCS group), gallbladder bile and tissue from 23 patients with gallbladder disease (CCT group), and eight patients without hepatobiliary disease (control group). H. pylori was examined by PCR with two different primers. PCR was positive in 4/43 (9.3%) by 26 kDa protein antigen primer and in 5/43 (11.6%) by urease A gene primer in bile from the PTCS group. However, in intrahepatic duct tissue, PCR was positive in only one case. PCR of gallbladder bile, tissue, and intrahepatic duct stones was negative. Upon intrahepatic bile analysis, the pH was significantly lower in PCR-positive than in negative cases (P < 0.05). In conclusion, H. pylori DNA may be present in the bile when there are certain environmental changes, such as lowered pH; however, H. pylori does not colonize the bile duct epithelium. We could find no pathogenetic role for H. pylori in the formation of hepatolithiasis.

Detection of Helicobacter pylori DNA in human biliary tree and its association with hepatolithiasis

Recently, several authors have reported that Helicobacter pylori DNA has been found in human bile. The aim of this study is to investigate the presence of H. pylori in the biliary tree of Koreans, including the bile, biliary epithelium, and gallstones. This study analyzed intrahepatic bile, bile duct tissue, and gallstones from 43 patients with hepatobiliary disease (PTCS group), gallbladder bile and tissue from 23 patients with gallbladder disease (CCT group), and eight patients without hepatobiliary disease (control group). H. pylori was examined by PCR with two different primers. PCR was positive in 4/43 (9.3%) by 26 kDa protein antigen primer and in 5/43 (11.6%) by urease A gene primer in bile from the PTCS group. However, in intrahepatic duct tissue, PCR was positive in only one case. PCR of gallbladder bile, tissue, and intrahepatic duct stones was negative. Upon intrahepatic bile analysis, the pH was significantly lower in PCR-positive than in negative cases (P < 0.05). In conclusion, H. pylori DNA may be present in the bile when there are certain environmental changes, such as lowered pH; however, H. pylori does not colonize the bile duct epithelium. We could find no pathogenetic role for H. pylori in the formation of hepatolithiasis.

Telomerase activity in pure pancreatic juice for the diagnosis of pancreatic cancer may be complementary to K-ras mutation

BACKGROUND

The usefulness of K-ras mutation in pancreatic juice for the diagnosis of pancreatic cancer is questionable. Telomerase is positive in pancreatic cancer but rarely in benign pancreatic diseases. We conducted this study to determine the usefulness of K-ras mutation and telomerase activity in pancreatic juice for the diagnosis of pancreatic cancer.

METHODS

Pancreatic juice collected during endoscopic retrograde cholangiopancreatography was examined in 31 patients: 12 with pancreatic cancer, 11 with chronic pancreatitis, and 8 control patients. The K-ras gene was detected by using the restriction fragment length polymorphism method. Telomerase activity was detected by using the telomeric repeat amplification protocol.

RESULTS

K-ras mutation was positive in 75% (9 of 12) of pancreatic cancers and in 27% (3 of 11) of cases of chronic pancreatitis but in none of the control patients. Telomerase activity was detected in 92% (11 of 12) of pancreatic cancers and in 18% (2 of 11) of cases of chronic pancreatitis. The diagnostic value in pancreatic cancer was comparable between K-ras mutation and telomerase when evaluated separately. However, by combining these 2 methods, the specificity rose to 100%.

CONCLUSIONS

For the diagnosis of pancreatic cancer, telomerase activity in pancreatic juice may possibly be complementary to K-ras mutation because it may decrease the rate of false-positive diagnosis.

Mucin-hypersecreting bile duct tumor characterized by a striking homology with an intraductal papillary mucinous tumor (IPMT) of the pancreas

BACKGROUND AND STUDY AIMS

The mucin-hypersecreting bile duct tumor, which closely resembles an intraductal papillary mucinous tumor (IPMT) of the pancreas, is rare, and its clinical features are not well known. We report our experience of nine patients with this type of tumor, and analyze the data in order to elucidate its clinicopathologic characteristics.

PATIENTS AND METHODS

Between 1995 and 1998, nine consecutive patients (four men, five women; mean age 54) who were diagnosed as having a mucin-hypersecreting bile duct tumor were enrolled in this study.

RESULTS

Recent or previous attacks of biliary pain and acute cholangitis were reported by most of the patients. Characteristics included a widely open ampulla of Vater with extrusion of mucin, and a diffuse dilated intrahepatic and extrahepatic bile duct with amorphous filling defects on cholangiogram. On cholangioscopic examination, a papillary mass or minute mucosal lesion was found in the dilated bile duct containing thick viscid mucin. Nine patients were referred for an operation, and curative resection was performed in eight of them. Using histologic examination, well differentiated adenocarcinoma in the background of benign hyperplasia and adenoma was documented in all patients except one, who showed pure adenoma.

CONCLUSION

The mucin-hypersecreting bile duct tumor can be characterized by a striking homology with IPMT of the pancreas in clinical, radiologic, and pathologic features.

Genistein produces reduction in growth and induces apoptosis of rat RPE-J cells

PURPOSE

To investigate the effect of the tyrosine kinase inhibitor, genistein, on the growth of the retinal pigment epithelial (RPE) cell.

METHODS

The tyrosine kinase inhibitor, genistein, was administered in culture to the rat retinal pigment epithelial cell line, RPE-J. The effect on cell viability and growth was assessed by trypan blue dye exclusion. Induction of apoptosis was confirmed morphologically by light and electron microscopy and oligonucleosomal fragmentation was assessed by TUNEL and DNA ladder. Quantitation was undertaken by propidium iodide staining and photometric enzyme immunoassay. Western blot was performed to study poly-(ADP-ribose)-polymerase cleavage (PARP). To confirm the involvement of caspase, the caspase inhibitor z-VAD-fmk was employed. In addition, cell cycle phase was determined by flow cytometry.

RESULTS

We here demonstrate that genistein treatment of RPE-J cells produces a dose- and time-dependent growth inhibition. Genistein in higher concentration induces apoptosis of rat RPE-J cell. z-VAD-fmk inhibited this type of apoptosis and cleavage of PARP enzyme was demonstrated. Ten micromolar genistein inhibited cell proliferation by G(0)/G(1) arrest without inducing apoptosis of the major population. Whereas 50 microM genistein caused growth inhibition of RPE-J cells by G(2)/M arrest and subsequent apoptotic death.

CONCLUSIONS

Genistein inhibits RPE cell growth and induces apoptosis. The ability of genistein to inhibit the proliferation and to induce apoptosis of RPE cells could be potentially therapeutic for proliferative vitreoretinopathy.

5-(beta-Cyclodextrinylamino)-5-Deoxy-alpha-D-Riboses as Models for Nuclease, Ligase, Phosphatase, and Phosphorylase

beta-Cyclodextrin derivatives crowned with ribose rings (such as 1) catalyzed the hydrolysis, esterification, and phosphorylation of catechol-derived phosphate esters. The vicinal cis-diols on the ribose groups appear to play a major role in the catalytic activity of these enzyme models by the formation of hydrogen bonds which activate the phosphorus atom to nucleophilic attack.

Endoscopic hemostasis in sphincterotomy-induced hemorrhage: its efficacy and safety

BACKGROUND AND STUDY AIMS

Hemorrhage is induced in approximately 0.5-12% of endoscopic biliary sphincterotomy (ES) procedures. We prospectively investigated the risk factors for ES-induced hemorrhage and evaluated the safety as well as the effectiveness of endoscopic hemostasis.

PATIENTS AND METHODS

The study included 1304 patients who underwent ES between July 1996 and June 1998. Epinephrine spray was used initially for hemostatic treatment. If bleeding persisted, an epinephrine injection was given consecutively. In patients with exposed vessels, epinephrine injection followed by alcohol injection was given.

RESULTS

ES-induced hemorrhage occurred in 136 (10.4%) patients. The type of sphincterotome used (needle-knife sphincterotome, P=0.025) and the cutting speed (the so-called "zipper" cut, P = 0.049) were revealed as significant variables with regard to the occurrence of bleeding. Mild, moderate, and severe bleeding were noted in 108 (79.4%), 22 (16.2%), and six (4.4%) patients, respectively. Once bleeding occurred, patients with an associated ampullary lesion (impacted stone or cancer) or with coagulopathy were more likely to bleed profusely. Initial hemostasis was achieved in all patients. However, rebleeding occurred in eight patients who were initially classified as having moderate or severe bleeding. Finally, ES-induced hemorrhage was successfully controlled in all patients after 1-3 treatment sessions (mean 1.1 sessions). The difference in the incidence of complications between the groups treated or not treated by endoscopic hemostasis was not statistically significant.

CONCLUSIONS

ES-induced hemorrhage occurred in 10% of the patients studied. The use of needle-knife sphincterotomy and the cutting speed were independent risk factors for the occurrence of bleeding. Once bleeding occurred, its severity was affected by an associated ampullary lesion (impacted stone or cancer) or coagulopathy. Endoscopic hemostasis with epinephrine and/or alcohol was effective and safe in ES-induced hemorrhage.

A new strategy for the application of CA19-9 in the differentiation of pancreaticobiliary cancer: analysis using a receiver operating characteristic curve

OBJECTIVE

Clinicians might be misled in interpreting an elevated CA19-9 when differentiating pancreaticobiliary cancer from benign clinical conditions such as acute cholangitis or cholestasis, because in these conditions, the concentration of CA19-9 may also be elevated. The aims of our study were to calculate new individual cutoff values for CA19-9 according to clinical situations using a receiver operating characteristic (ROC) curve and to define a new strategy for interpreting CA19-9 in pancreaticobiliary cancer.

METHODS

One hundred sixty patients with pancreatic diseases (cancer 90, benign disease 70), 322 patients with biliary tract diseases (biliary cancer 152, benign disease 170), and 20,035 asymptomatic controls were enrolled in the present study. An ROC curve was described by plotting the sensitivity on the y-axis against 1-specificity on the x-axis for each of several cutoff values.

RESULTS

The area under the ROC curve was significantly greater for pancreatic cancer than for biliary cancer (p < 0.05). For patients with pancreatic cancer, CA19-9 proved to be useful. At a cutoff value of 37 U/ml, sensitivity and specificity were 76.7% and 87.1%, respectively. For patients with biliary cancer, CA19-9 was not helpful. However, when patients with biliary disease were divided into two groups according to the presence of cholangitis or cholestasis, CA19-9 proved to be more useful for the group without cholangitis or cholestasis than for the group with cholangitis or cholestasis (p < 0.05). In the former group, the sensitivity and specificity of CA19-9 were 77.6% and 83%, respectively, at the cutoff value of 37 U/ml. For the latter group, the sensitivity and specificity of CA19-9 were 74% and 41.5% respectively, whereas the specificity reached 87% at 300 U/ml. CA19-9 in diagnosing pancreatic cancer was useful regardless of accompanying acute pancreatitis or cholestasis. The serum concentration of CA19-9 in asymptomatic individuals was 9.42 +/- 9.95 U/ml. Only 1 of 157 patients with a concentration of CA19-9 above 37 U/ml was found to have gallbladder cancer. The positive and negative predictive values were 0.65% and 0.78%, respectively.

CONCLUSIONS

The use of CA19-9 for the differentiation of pancreaticobiliary cancer should be applied individually, depending on the clinical situation.

Choledochal cyst associated the with anomalous union of pancreaticobiliary duct (AUPBD) has a more grave clinical course than choledochal cyst alone

OBJECTIVE

Since choledochal cyst is frequently associated with the anomalous union of pancreaticobiliary duct (AUPBD), AUPBD has been regarded to be the etiologic factor of choledochal cyst. However, the clinical significance of AUPBD an patients with choledochal cyst has not been clearly defined. Therefore, to clarify the significance of AUPBD in choledochal cyst patients, we compared the clinical features of patients with choledochal cyst according to the presence or absence of AUPBD.

METHODS

Among 52 cases which were diagnosed as choledochal cyst out of 5,037 ERCP referrals between August 1990 and December 1996, we selected 44 cases, in which the pancreaticobiliary junction was clearly visualized on cholangio-pancreaticography. These cases were divided into AUPBD-present group (n = 28) and AUPBD-absent group (n = 16). Clinical features were compared between the two groups. Furthermore, in AUPBD-present group, clinical data were also analyzed according to Kimura's classification of AUPBD.

RESULTS

In our study, AUPBD was associated with choledochal cyst in 28 (64%) cases. AUPBD was found only in type I and IV according to Todani's classification of choledochal cyst. There were no significant differences between the AUPBD-present group and the AUPBD-absent group in the incidence of gallstone disease, while the incidence of acute inflammation was 93% (26/28) in the AUPBD-absent group (p < 0.01). Carcinoma developed only in the AUOBD-present group (9/28, 32%) (p < 0.05). Pancreatic disorders (i.e. pancreatic stone, pancreatitis or pancreatic cancer) occurred in 12 of 28 cases in the AUPBD-present group (43%), while only in 1 of 16 cases in the AUPBD-absent group (6%) (p < 0.05).

CONCLUSION

AUPBD associated with choledochal cyst may have implications not only as a possible etiologic factor but also as an important factor that may affect the clinical course, surgical planning and prognosis. In cases with choledochal cyst, we should make an effort to evaluate the presence of AUPBD.

Human immune response to a Pseudomonas aeruginosa outer membrane protein vaccine

In order to evaluate in humans the safety and immunogenicity of a Pseudomonas aeruginosa vaccine composed of outer membrane proteins (OMPs), CFC-101, we carried out a phase I/IIa clinical trial in healthy male volunteers. Groups of six volunteers were immunized either subcutaneously (s.c.) or intramuscularly (i.m.) with three dosages of the vaccine three times at 7-day intervals. The vaccine was well tolerated by volunteers. Local reactions in the injection sites were generally mild and transient. Significant increases in OMP-specific antibody were observed in both route groups after vaccinations but was higher in the i.m.-immunized group, where vaccination with 0.5 or 1.0 mg doses yielded 100% seroconversion. The specificity of the induced antibodies to P. aeruginosa OMP was demonstrated by western blot analysis and immunoprecipitation assay. An increase in Clq-binding capacity and ability to confer mice protection from lethal challenges with P. aeruginosa indicated the protective efficacy of the elicited antibodies. Based on these data, we concluded that the P. aeruginosa OMP vaccine is safe and effective in humans with an optimal dose of 0.5 and 1.0 mg and that i.m. is the better route than s.c. for this vaccine.

Thyroglossal duct cyst with papillary carcinoma in an 11-year-old girl

A case of primary papillary carcinoma arising in a thyroglossal duct cyst is reported in a young girl. This is a rare finding, with only five pediatric cases in the total of 115 cases reported in the literature. Subsequent management is described, including the role of scintigraphy and radioiodine ablation.

A case of adult-onset Bartter's syndrome

Bartter's Syndrome is characterized by renal potassium wasting with hypokalemia, metabolic alkalosis, increased renin-angiotensin-aldosterone system, normal blood pressure, resistance to the pressor effects of angiotensin II and juxtaglomerular cell hyperplasia. Most of the cases have been noted in the pediatric age group and adult-onset cases are very rare. We report a case of adult-onset Bartter's syndrome.

Impairement of endothelium-dependent relaxation in chronic two-kidney, one clip hypertensive rats

OBJECTIVES

Hypertension is commonly associated with an endothelial dysfunction that may contribute to the rise in blood pressure. Little information has been available so far on the role of endothelium-derived nitric oxide(EDNO) in renin-dependent, 2-kidney, 1 clip(2KIC) hypertension. The present study was aimed to determine a role for EDNO in the development and maintenance of 2KIC hypertension.

METHODS

The effects of blocking synthesis or supplementation with precursor of EDNO on the development of hypertension were determined in 2KIC rats. Vascular responses to acetylcholine, nitroprusside, atrial natriuretic peptide and nifedipine were examined in 7- and 12-week hypertensive 2KIC rats.

RESULTS

NG-nitro-L-arginine-methyl ester caused a sustained increase of blood pressure in normal rats, while it was only partially associated with a more pronounced increase of blood pressure in the developmental phase of hypertension in 2KIC rats. In 7-week and 12-week hypertensive rats, phenylephrine-induced contraction of the isolated thoracic aortic rings was more sensitive compared with control. Their acetylcholine-induced relaxation was attenuated while the responses to nitroprusside or atrial natriuretic peptide were unaltered. Although their blood pressure did not differ between 7-week and 12-week hypertensive groups, the attenuation in the acetylcholine-induced relaxation was more prominent in the latter with a longer duration of hypertension. Indomethacin did not affect the attenuated relaxation to acetylcholine. The relaxation response to nifedipine was more pronounced in 2KIC rats.

CONCLUSION

These results indicate that ENDO has little influence of the 2KIC hypertension, at least during its developmental phase, which is associated with an activated reninangiotensin system. The chronic stage of 2KIC hypertension, however, is associated with an endothelial dysfunction which may contribute to the enhanced vasoconstriction and sustained high blood pressure.