17ß-estradiol inhibits mesenchymal stem cells-induced human AGS gastric cancer cell mobility via suppression of CCL5- Src/Cas/Paxillin signaling pathway.

Gender differences in terms of mortality among many solid organ malignancies have been proved by epidemiological data. Estrogen has been suspected to cast a protective effect against cancer because of the lower mortality of gastric cancer in females and the benefits of hormone replacement therapy (HRT) in gastric cancer. Hence, it suggests that 17ß-estradiol (E2) may affect the behavior of cancer cells. One of the key features of cancer-related mortality is metastasis. Accumulating evidences suggest that human bone marrow mesenchymal stem cells (HBMMSCs) and its secreted CCL-5 have a role in enhancing the metastatic potential of breast cancer cells. However, it is not clear whether E2 would affect HBMMSCs-induced mobility in gastric cancer cells. In this report, we show that CCL-5 secreted by HBMMSCs enhanced mobility in human AGS gastric cancer cells via activation of Src/Cas/Paxillin signaling pathway. Treatment with specific neutralizing antibody of CCL-5 significantly inhibited HBMMSCs-enhanced mobility in human AGS gastric cancer cells. We further observe that 17ß-estradiol suppressed HBMMSCs-enhanced mobility by down-regulating CCL5-Src/Cas/paxillin signaling pathway in AGS cells. Collectively, these results suggest that 17ß-estradiol treatment significantly inhibits HBMMSCS-induced mobility in human AGS gastric cancer cells.

Cost-Utility Analysis of Tenofovir Alafenamide and Entecavir in Chronic Hepatitis B Patients: A Markov Decision Model.

From the perspective of health economics, the evaluation of drug-related cost effectiveness and clinical utility is crucial. We conducted a cost-utility analysis of two first-line drugs, tenofovir alafenamide (TAF) and entecavir (ETV), in the treatment of chronic hepatitis B (CHB) patients. We performed inverse probability of treatment weighting (IPTW) to match the independent variables between the two treatment groups. The incremental cost effectiveness ratio (ICER) of the two treatment groups was simulated using a decision tree with the Markov annual-cycle model. A total of 54 patients treated with TAF and 98 with ETV from January 2016 to December 2020 were enrolled. The total medical cost in the TAF group was NT$76,098 less than that in the ETV group, and TAF demonstrated more effectiveness than ETV by 3.19 quality-adjusted life years (QALYs). When the time horizon was set at 30 years, the ICER of the TAF group compared with the ETV group was -NT$23,878 per QALY, suggesting more cost savings for TAF. Additionally, with the application of TAF, over NT$366 million (approximately US$12 million) can be saved annually. TAF demonstrates cheaper medical costs and more favorable clinical QALYs than ETV. To balance health insurance benefits and cost effectiveness, TAF is the optimal treatment for CHB.

Evaluation of the Bactec MGIT 960 system in combination with the MGIT TBc identification test for detection of Mycobacterium tuberculosis complex in respiratory specimens.

The sensitivity and specificity of the MGIT TBc identification (TBc ID) test for Mycobacterium tuberculosis complex (MTC) detection in positive Bactec MGIT cultures were 95.2% and 99.2%, respectively. When MTC-positive results obtained from two additional molecular methods were included, the sensitivity of the MGIT TBc ID test was 85.4%, while that of culture was 95.7%.

Evaluation of the Cobas TaqMan MTB test for direct detection of Mycobacterium tuberculosis complex in respiratory specimens.

The Cobas TaqMan MTB test, based on real-time PCR technology, was evaluated for direct detection of Mycobacterium tuberculosis complex (MTBC) in respiratory specimens. A total of 1,093 samples from 446 patients, including 118 acid-fast smear-positive and 975 acid-fast smear-negative specimens, were investigated. Diagnostic cultures performed with 7H11 agar, Löwenstein-Jensen medium, and the Bactec MGIT 960 system were considered the reference methods. When discrepant results between the Cobas TaqMan MTB test and culture occurred, additional results from the BD MGIT TBc identification test and the GenoType Mycobacterium CM test performed on growth-positive and acid-fast-stain-positive MGIT tubes and review of the patient's medical history were used for discrepancy analysis. The overall sensitivity, specificity, positive predictive value, and negative predictive value for the Cobas TaqMan MTB test were 91.5%, 98.7%, 91.5%, and 98.7%, respectively. In general, the performance of the new Cobas TaqMan MTB test was comparable to that of the replaced Cobas Amplicor MTB system. The most prominent feature of the new system was its extraordinarily high sensitivity (79.5%) for detecting MTBC in smear-negative specimens; out of 44 smear-negative but culture-positive specimens, 35 were positive by the new system. The Cobas TaqMan MTB assay, including DNA extraction, can be completed within 3 h.

Rabeprazole can overcome the impact of CYP2C19 polymorphism on quadruple therapy.

OBJECTIVES: The prospective study was designed to clarify the impact of CYP2C19 on quadruple therapies and survey the efficacies of rabeprazole-based quadruple therapy for Helicobacter pylori infection after failure of standard triple therapies. PATIENTS AND METHODS: From January 2007 to March 2009, 1055 H. pylori-infected patients received standard triple regimens (proton-pump inhibitor (PPI), clarithromycin, and amoxicillin). Helicobacter pylori eradication was achieved in 865 (81.9%) subjects. One hundred ninety eradication-failure patients were enrolled and randomly assigned to receive a 7-day eradication therapy. Ninety-six patients were treated with esomeprazole-based quadruple rescue therapies (EB), while 94 patients were treated with rabeprazole-based quadruple rescue therapies (RB). Follow-up endoscopy was done 16 weeks later to assess the treatment response. Patients' responses, CYP2C19 genotypes, and antibiotics resistances were also examined. RESULTS: Intention-to-treat analysis revealed that RB had better eradication rates than EB (EB: 72.9%; 95% CI: 64.9-80.9% and RB: 78.7%; 95% CI 72.5-84.9%) (p value = .543). Per-protocol results were EB = 75.3%; 95% CI: 70.3-80.3% and RB = 85.1%; 95% CI: 80.6-89.6% (p value = .0401). Both regimens had similar compliance (p value = 0.155) and adverse events (p value = 0.219). We also surveyed those patients without resistance of any antibiotics. RB still showed better outcome than EB. Our data showed that esomeprazole-based regimen and CYP2C19 Hom EM genotype were important predictors for eradication failure. CONCLUSIONS: In quadruple therapy, rabeprazole-based regimens had better efficacy than esomeprazole-based regimens. CYP2C19 polymorphism also played an important role in quadruple therapy. It seems advisable to change PPI to rabeprazole in second-line quadruple therapy.

Evaluation of a membrane hybridization array for detection of Mycobacterium tuberculosis complex and resistance to isoniazid and rifampin in sputum specimens, mycobacterial liquid cultures, and clinical isolates.

The gold standard of antituberculosis susceptibility testing is based on culture method which takes weeks. Rapid detection of resistance to isoniazid (INH) and rifampin (RIF) to avoid inappropriate regimens and to prevent transmission of resistant strains are important. A membrane array (BluePoint MTBDR) was developed to identify Mycobacterium tuberculosis complex (MTBC) and the genetic mutations responsible for resistance to RIF and INH. We aimed to evaluate the performance of this array for diagnosing drug-resistant MTBC. A total of 261 acid-fast bacilli positive sputum specimens, 1025 positive mycobacteria growth indicator tube (MGIT) cultures and 544 clinical isolates were analyzed. Antituberculosis susceptibility testing was the gold standard and was performed on MTBC isolated from positive MGIT cultures and on 544 clinical isolates. The sensitivity and specificity of the array to detect MTBC were 62.2% and 88.1% for sputum specimens, 100% and 97.9% for MGIT cultures. For detection of drug-resistant MTBC in positive MGIT tubes, the sensitivities of the array were 100% for RIF and 97.1% for INH, while the specificities were 99.7% and 100%, respectively. Interestingly, we noticed four genotypically RIF-resistant but phenotypically RIF-susceptible isolates and eight genotypically INH resistant but phenotypically INH-susceptible isolates. Comparing with conventional culture methods for species identification and drug susceptibility testing, the BluePoint MTBDR assay demonstrated to be a rapid test with high sensitivity and specificity to identify MTBC and to detect isoniazid and rifampin resistance when it is applied to broth culture specimens and clinical isolates.

Hemorrhagic bullae caused by Bacteroides fragilis in a patient with intra-abdominal infection.

Skin manifestations due to intra-abdominal infection are uncommon but could be a warning sign of severe infection. We report a 58-year-old uremic female who had acute cholecystitis and pneumatosis intestinalis. She developed periumbilical hemorrhagic bullae and finally had a fatal outcome with medical therapy. Severe intra-abdominal infection such as pneumatosis intestinalis should be suspected when periumbilical bullae increase in size.

San-Huang-Xie-Xin-Tang inhibits Helicobacter pylori-induced inflammation in human gastric epithelial AGS cells.

Helicobacter pylori infection leads to gastroduodenal inflammation, peptic ulceration, gastric lymphoma and gastric cancer. Certain herbal remedies have been used to treat gastric disease. In this study, we examined the anti-inflammatory effect of San-Huang-Xie-Xin-Tang (SHXT) and its main component baicalin on Helicobacter pylori-infected human gastric epithelial AGS cell. AGS cells were treated with Helicobacter pylori at a bacterium/cell ratio of 300:1. mRNA expression and protein levels were determined by reverse transcriptase-polymerase chain reaction (RT-PCR) analysis and western blot analysis, respectively. Interleukin-8 (IL-8) level and the translocation of nuclear factor kappa B (NF-kappaB) were measured by enzyme-linked immunosorbent assay (ELISA) and enzyme-linked DNA-protein interaction assay (ELDIA), respectively. Nitric oxide production was measured by Griess reagent. We found that SHXT and baicalin inhibited Helicobacter pylori-induced cyclooxygenase-2 (COX-2) enhancement and IkappaBalpha degradation in both mRNA and protein levels. SHXT and baicalin also inhibited Helicobacter pylori-induced inducible nitric oxide synthase (iNOS) and IL-8 mRNA expression, and decreased NO and IL-8 production. Furthermore, SHXT and baicalin inhibited nuclear translocation of p50 subunit of NF-kappaB in Helicobacter pylori-infected AGS cells. Based on the above findings, SHXT and baicalin might exert anti-inflammatory and gastroprotective effects in Helicobacter pylori-induced gastric inflammation.

Evaluation of urine ELISA test for detecting Helicobacter pylori infection in Taiwan: a prospective study.

AIM: To evaluate the diagnostic accuracy and clinical utility of a new ELISA (URINELISA) test for detecting Helicobacter pylori (H pylori) antibody in the urine of Taiwanese population. METHODS: In this prospective study, 317 consecutive dyspeptic patients (171 men, 146 women; mean age, 51.0 years) were included. They underwent gastroendoscopy for evaluation. Invasive tests, including culture, histology, and rapid urease test (RUT), and non-invasive (13)C-urea breath test were preformed. At the same time, urine specimens were collected for URINELISA. The status of H pylori infection was considered as positive when either culture was positive, or when two of the other, RUT, histology or 13C-UBT, were positive. RESULTS: The sensitivity, specificity, positive predictive value, and negative predictive value of URINELISA are 91.7% (211/230), 90.8% (79/87), 96.3% (211/219), and 80.6% (79/98) respectively. CONCLUSION: This URINELISA test is reliable, inexpensive and easy-to-use. The high diagnostic accuracy warrants the use of URINELISA as a first-line screening tool for diagnosis of H pylori infection in untreated patients.

The best method of detecting prior Helicobacter pylori infection.

AIM: Prior Helicobacter pylori (H pylori) infection has often been underestimated. These underestimations have misled physicians attempting to determine the significance between H pylori and certain gastrointestinal lesions such as intestinal metaplasia, atrophic gastritis, and gastric cancer. Our study endeavored to detect past H pylori infections accurately, easily, and rapidly with the newly developed immunoblot kit, Helico Blot 2.1. METHODS: Thirty-three patients, including 25 H pylori infected and 8 uninfected cases, were enrolled in our study. All patients received consecutive gastroendoscopic examinations and (13)C-urea breath test (UBT) tests at 6- or 12-mo intervals for up to 4 years. Serum samples were obtained from each patient at the same time. Intragastric H pylori infection was confirmed in accordance with the gold standard. Twenty-five H pylori-infected patients received triple therapies after initial bacterial confirmation, and were successful in eradicating their infections. Serially obtained sera were tested by means of Helico Blot 2.1. RESULTS: Current infection marker detected by Helico Blot 2.1 was unreliable for representing ongoing H pylori infection. Only 35 and 37 ku antibodies of H pylori had significant seroconversion rates 1 year after having been cured. The seropositive rates of 116 ku (cytotoxin-associated antigen (CagA)) and Helico Blot 2.1 were nearly 100% during 4-year follow-up period. Both CagA antigen and Helico blot 2.1 could serve as indicators of long-term H pylori infection. CONCLUSION: Helico Blot 2.1 can detect past H pylori infections for up to 4 years, and is the best method to date for detecting previous long-term H pylori infection.

Capsaicin-induced cell death in a human gastric adenocarcinoma cell line.

AIM: Capsaicin, a pungent ingredient found in red pepper, has long been used in spices, food additives, and drugs. Cell death induced by the binding of capsaicin was examined in a human gastric adenocarcinoma cell line (AGS cells). METHODS: By using XTT-based cytotoxicity assay, flow cytometry using the TUNEL method, and quantitation of DNA fragmentation, both cell death and DNA fragmentation were detected in AGS cells treated with capsaicin. By using Western blotting methods, capsaicin reduced the expression of Bcl-2, the antiapoptotic protein, in AGS cells in a concentration-dependent manner. RESULTS: After incubation of AGS cells with capsaicin for 24 h, cell viability decreased significantly in a dose-dependent manner. After incubation of AGS cells with capsaicin for 24 h, apoptotic bodies also significantly increased, and were again correlated with the dose of capsaicin. When the concentration of capsaicin was 1 mmol/L, the amount of DNA fragments also increased. Similar results were also in the lower traces. CONCLUSION: These results suggest that capsaicin-induced cell death might be via a Bcl-2 sensitive apoptotic pathway. Therefore, capsaicin might induce protection from gastric cancer.

Risk of microbial contamination of unit-dose eyedrops within twenty four hours after first opening.

The purpose of this study was to evaluate the risk of microbial contamination of sterile, preservative-free, unit-dose ocular medications within 24 h after the first opening. Four different unit-dose ocular medications (cromolyn sodium, timolol, gentamicin sulfate, and betamethasone) in 1 mL containers, were tested. After opening, the preparations were stored in an acrylic protector with or without cap, at room temperature or in a refrigerator at 4 degrees C. Samples were collected for microbiological cultures at 0, 4, 10, 14, and 24 h after opening from the identical container. No bacteria or fungus was detected in the samples throughout the period of the study. Microbial air contamination of the experimental environment was also studied. The culture results of environmental microbial air contamination were positive for both bacteria and fungi. This study suggests that unit-dose eyedrops remain free of microbial air contamination for up to 24 h after the first opening.

Morphologic change and elevation of cortisol secretion in cultured human normal adrenocortical cells caused by mutant p21K-ras protein.

In our previous study on the tumorigenesis of human functional adrenal tumors, we observed a high frequency of K-ras point mutations in clinical specimens. Furthermore, we cloned the mutated K-ras gene from the tumors and inserted it into vectors to transfect normal bovine adrenocortical cells to express the mutated K-ras gene. The mRNA level of steroidogenic enzymes such as cholesterol sidechain cleavage enzyme (P450SCC), 17alpha-hydroxylase/17,20-lyase (P450c17), and 3beta-hydroxysteroid dehydrogenase (3betaHSD) in the mutant K-ras stably transfected cells were elevated. Cultured normal adrenocortical cells from donors and patients with adrenocortical tumors were then transfected with mutant K-ras expression plasmids constructed from human adrenal tumors. Stable transfectants grew faster than normal cells. Additionally, morphologic change was observed in the transfected cells. Moreover, when the synthesis of hormones was analyzed, the mRNA of P450SCC, P450C17, and 3betaHSD was found to have increased, and the level of cortisol was 18 to 25 times that in control cells. The increased steroid hormone production in mutant K-ras-transfected cells was reversed by lovastatin, a pharmacologic inhibitor of p21ras function. These results, combined with previous reports of steroidogenic K-ras in bovine adrenocortical cells, suggest that the K-ras oncogene is involved in steroidogenesis in human adrenocortical cells.

Higher frequency of apolipoprotein E2 allele in type 2 diabetic patients with nephropathy in Taiwan.

BACKGROUND: Diabetes is one of the major causes of end stage renal failure in Taiwan. Previous studies have indicated that lipid abnormalities might contribute to the development and progression of diabetic nephropathy (DN). Apolipoprotein E (apo E) regulates the metabolism of lipoproteins. Three different apo E alleles (epsilon2, epsilon3 and epsilon4) produce apo E isoproteins, apo E2, apo E3 and apo E4. Thus, the apo E gene polymorphism may be associated with DN. METHODS: To investigate the distribution of apo E genotype in type 2 diabetic Taiwanese, we examined 314 patients with type 2 diabetes (100 without nephropathy and 214 with nephropathy) and 150 age-matched normal controls. The diagnosis of nephropathy was made when daily protein loss exceeded 500 mg. The apo E gene polymorphism was analyzed by polymerase chain reaction. RESULTS: Our study found that the frequency of apo E2 allele was significantly higher in the diabetics with nephropathy- non-dialysis group (7.7%) and diabetics with nephropathy- dialysis group (7.7%) than in normal controls (1.7%) (p < 0.001) and diabetics without nephropathy (2.0%) (p < 0.01). The E3 and E4 allele frequencies were not significantly different among groups. CONCLUSION: These findings imply that apo E polymorphism is apparently related to the development of DN in type 2 diabetes in Taiwan.

Evaluation of a newly developed office-based stool test for detecting Helicobacter pylori: an extensive pilot study.

BACKGROUND/AIMS: Several strategies have been used to detect Helicobacter pylori (Hp) infection along two lines: 1) direct detection of the bacteria, and 2) detection of antigen-antibody assay against Hp. The non-invasive methods include ELISA test of serum, salivary and urine, urea breath test, and detection of Hp antigen in stool. The latter method (HpSA) has been proven reliable and better than the ELISA test, for it can detect current Hp infection and is suitable for post-treatment follow-up. Now, a new commercial kit, ImmunoCard STAT HpSA (Meridian Bioscience Europe) has been developed to detect stool Hp antigen. It is simpler and less time-consuming than HpSA. The aim was to examine whether ImmunoCard STAT HpSA is qualified for diagnosis of Hp infection. METHODOLOGY: 253 patients (163 men, 90 women, mean age: 53.3 +/- 13.9 y/o, range: 19-89 y/o) were enrolled in this study. All of them had undergone gastroendoscopy and urea breath test. 207 patients were diagnosed with peptic ulcer and 46 with gastritis. Stool samples were collected within 3 days of their visit for gastroendoscopy and were sent for the Immunocard test. RESULTS: 118 patients were diagnosed with Hp infection and of these, 113 were interpreted as positive by means of the Immunocard test. Among the other 135 patients without Hp infections, 123 were interpreted as negative by means of the Immunocard test. Sensitivity and specificity were 95.8% and 91.1%, and positive and negative predictive values were 90.4% and 96.1%. CONCLUSIONS: The ImmunoCard STAT HpSA had high sensitivity, and specificity and could be used for mass screening. We concluded that it is a rapid, simple, cheap, reliable, and non-invasive strategy to detect current Hp infection and can be used in post-Hp eradication follow-up in Taiwan.

The clinical utility of string-PCR test in diagnosing Helicobacter pylori infection.

BACKGROUND/AIMS: Non-invasive string test has been reported as being convenient and capable of yielding bacteria by means of gastric juice sampling in the diagnosis of Helicobacter pylori infection. Molecular methods, such as polymerase chain reaction for the amplification of DNA, are desirable for the detection of minute quantities of H. pylori. We planned to evaluate the diagnostic efficiency of the combination of the string test and polymerase chain reaction and determine whether the string polymerase chain reaction test could obtain more information in conditions where the bacterial load is so low that other diagnostic tests fail to confirm the presence of H. pylori. METHODOLOGY: We enrolled 48 dyspeptic patients, including 29 males and 19 females, with a mean age of 52.5 years. Each patient received endoscopy and biopsy-based tests, including RUT (rapid urease test), cultures, and histology, followed by 13C-UBT (13Carbon urea breath test). We used the string test, (Entero-Test H. pylori, HDC Corporation, CA, US), for gastric juice sampling. The specimen was further analyzed by polymerase chain reaction for the presence of H. pylori with the primer for cagA gene, which is highly prevalent in Taiwan. H. pylori infection was considered as positive when either culture yield was positive, or when two of the other three tests, including RUT, histology, and 13C-UBT, were positive. RESULTS: Of the total 48 patients, 34 patients were H. pylori-positive, and 14 were H. pylori-negative. A fragment of 349 bp of polymerase chain reaction products was detected by agarose gel electrophoresis in 32 out of 34 patients who was classified as H. pylori-positive. The sensitivity, specificity, positive predictive value, and negative predictive value of the string polymerase chain reaction test were 94.12%, 96.97%, 92.86%, and 86.67%, respectively. These results are comparable to 13C-UBT and RUT, and better than histology and culture. One subject, who tested as H. pylori-negative according to the diagnostic criteria, had positive 13C-UBT and string polymerase chain reaction test results. Further sequencing of the DNA obtained from the results of polymerase chain reaction product was performed and it showed 98% identities with the known sequence of cagA strain H. pylori (GenBank accession number: AF249275). CONCLUSIONS: The string polymerase chain reaction test is non-invasive and provides direct bacterial yields. Its diagnostic efficiency is comparable with 13C-UBT and RUT in detecting H. pylori infection. Also, with the assistance of polymerase chain reaction and DNA sequencing, we can diagnose H. pylori infection even when the bacterial load is low. Further application of string polymerase chain reaction test in the genetic analysis of virulent and resistant strains seems promising.

Does long-term use of silver nanoparticles have persistent inhibitory effect on H. pylori based on Mongolian gerbil's model?

BACKGROUND: It is urgent to find alternative agents due to increasing failure rate of Helicobacter pylori (H. pylori) eradication. The study surveyed the long-term effect of silver nanoparticles (AgNP) on H. pylori based on Mongolian gerbil's model. MATERIALS AND METHODS: Fifty gerbils were randomly allocated to six groups (A-F). Group (Gr) A: the gerbils were fed with broth; Gr B and D: the gerbils were fed with AgNP/clay complex (0.1% of weight); Gr C and E: the gerbils were fed with AgNP/clay complex(1% of weight); and Gr D, E, and F: the gerbils were inoculated with H. pylori. At the 20th experimental week, the gerbils were sacrificed. Histology was evaluated according to the classification of the Sydney system. P < 0.05 was considered to be statistically significant. RESULTS: The AgNP/clay has more obvious inhibitory effect on H. pylori in vitro. There was a trend of higher concentrations of AgNP with stronger inhibitory effect on H. pylori growth (P = 0.071). There were no significant differences of inflammation among groups D, E, and F (P = 0.688). CONCLUSION: AgNP/clay would be a potential and safe agent for inhibiting H. pylori. It should be helpful for eradication of H. pylori infection.

Evaluation of a membrane array for detection of Mycobacterium tuberculosis complex and nontuberculous mycobacteria in positive liquid cultures.

Molecular identification of mycobacteria in positive Mycobacteria Growth Indicator Tube (MGIT) cultures can accelerate mycobacterial diagnosis. A membrane hybridization array (Blue Point) was evaluated for this purpose in 284 positive MGIT cultures. Discrepant results were resolved by testing with the GenoType Mycobacterium kit, TBc ID test, sequencing of the 16S rRNA gene and internal transcribed spacer. Total recovery from culture and the array (if confirmed) was considered 100%. The sensitivity, specificity, positive, and negative predictive values of the array for detection of Mycobacterium tuberculosis complex were 99.4%, 100%, 100%, and 99.2%, respectively, while the corresponding values of culture were 95.1%, 100%, 100%, and 93.8%, respectively, with significant differences in sensitivity and negative predictive value being found between the 2 methods. The recoveries of nontuberculous mycobacteria and mixed cultures of the array were also significantly higher than those of culture. The array can be adopted in routine mycobacteriology laboratory.

Dual specimens increase the diagnostic accuracy and reduce the reaction duration of rapid urease test.

AIM: To evaluate the influence of multiple samplings during esophagogastroduodenoscopy (EGD) on the accuracy of the rapid urease test, and the validity of newly developed rapid urease tests, HelicotecUT plus test and HelicotecUT test, CLO test and ProntoDry test. METHODS: A total of 355 patients undergoing EGD for dyspepsia were included. Their Helicobacter pylori (H. pylori) treatment status was either naïve or eradicated. Six biopsy specimens from antrum and gastric body, respectively, were obtained during EGD. Single antral specimens and dual (antrum + body) specimens were compared. Infection status of H. pylori was evaluated by three different tests: culture, histology, and four different commercially available rapid urease tests (RUTs)-including the newly developed HelicotecUT plus test and HelicotecUT test, and established CLO test and ProntoDry test. H. pylori status was defined as positive when the culture was positive or if there were concordant positive results among histology, CLO test and ProntoDry test. RESULTS: When dual specimens were applied, sensitivity was enhanced and RUT reaction time was significantly reduced, regardless of their treatment status. Thirty minutes were enough to achieve an agreeable positive rate in all the RUTs. Both newly developed RUTs showed comparable sensitivity, specificity and accuracy to the established RUTs, regardless of patient treatment status, RUT reaction duration, and EGD biopsy sites. CONCLUSION: Combination of antrum and body biopsy specimens greatly enhances the sensitivity of rapid urease test and reduces the reaction duration to 30 min.

A tumorigenic homeobox (HOX) gene expressing human gastric cell line derived from putative gastric stem cell.

GOAL: Study the mechanism of gastric tumor development. BACKGROUND: We have generated and characterized a novel human gastric cell line, KMU-CS12 (CS12), from an immortal cell line, KMU-CSN (CSN; formerly named as GI2CS) which was derived from putative human gastric stem cell/progenitor cell clone, KMU-GI2. STUDY: The characterization of the CS12 cell line includes gene expression by immunocytochemical staining, cell proliferation and differentiation potential, cyotogenetic analysis by Giemsa banding and spectral karyotype analysis (SKY), and tumorigenicity in immune-deficient congenic inbred, nude mice (BALB/cAnN-Foxn1nu/CrlNarl). The Agilent Human 1A oligo-array and RT-PCR were also employed to analyze the expression of homeobox (HOX) genes. RESULTS: The CS12 gastric cell line showed cancer cell phenotypes, i.e. the ability of anchorage-independent growth high frequency (44%) and to the expression of Oct-4, a transcription factor expressed in embryonic stem cells and many types of cancer cells, and tumor development in immune deficient mice. SKY analysis indicated a characteristic duplication of the short arm of chromosome 7 to chromosome 12. Agilent Human 1A oligo-array analysis showed that the expression of 1145 genes was upregulated while that of 890 genes was downregulated in CS12 cells. RT-PCR revealed that homeobox genes (HOXA4, HOXA5, HOXA7, HOXA9, and HOXA13) were highly expressed in CS12 cells in culture, as well as tumor tissues developed by CS12 cells in immunodeficient mice for six to eight weeks. CONCLUSION: Except for the duplication of the short arm of Chromosome 7 on Chromosome12, the karyotype of the tumorigenic CS12 cells is similar to the parental GI2 cells which are non-tumorigenic and normal in karyotype. This chromosomal change could be the cause for the high expression of HOXA genes and tumorigenicity of these cells found in this study. Thus HOXA genes might play an important role in gastric carcinogenesis.