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

AIM:To evaluate the influence of multiple samplings during esophagogastr oduodenoscopy(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 nave 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 signif icantly 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,specif icity 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.

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 capsaidn 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 fragmentaUon 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.

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 pylorl） antibody in the urine of Taiwan Residents 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 ^13C-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 Hpyloriinfection in untreated patients.

The best method of detecting prior Helicobacter pylorimfection

AIM： Prior Helicobacterpylori （Hpylori infection has often been underestimated. These underestimations have misled physicians attempting to determine the significance between Hpyloriand certain gastrointestinal lesions such as intestinal metaplasia, atrophic gastritis, and gastric cancer. Our study endeavored to debit past Hppylorinfections accurately, easily, and rapidly with the newly developed irnmunoblot 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 ^3C-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 Hpylori infection. Only 35 and 37 ku antibodies of H pylorihad significant seroconversion rates 1 year after having been cured. The seroposiUve 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. 2005 The WJG Press and Elsevier Inc. All rights reserved.