Reproducibility of up-flow column percolation tests for contaminated soils.

Up-flow column percolation tests are used at laboratory scale to assess the leaching behavior of hazardous substance from contaminated soils in a specific condition as a function of time. Monitoring the quality of these test results inter or within laboratory is crucial, especially if used for Environment-related legal policy or for routine testing purposes. We tested three different sandy loam type soils (Soils I, II and III) to determine the reproducibility (variability inter laboratory) of test results and to evaluate the difference in the test results within laboratory. Up-flow column percolation tests were performed following the procedure described in the ISO/TS 21268-3. This procedure consists of percolating solution (calcium chloride 1 mM) from bottom to top at a flow rate of 12 mL/h through softly compacted soil contained in a column of 5 cm diameter and 30 ± 5 cm height. Eluate samples were collected at liquid-to-solid ratio of 0.1, 0.2, 0.5, 1, 2, 5 and 10 L/kg and analyzed for quantification of the target elements (Cu, As, Se, Cl, Ca, F, Mg, DOC and B in this research). For Soil I, 17 institutions in Japan joined this validation test. The up-flow column experiments were conducted in duplicate, after 48 h of equilibration time and at a flow rate of 12 mL/h. Column percolation test results from Soils II and III were used to evaluate the difference in test results from the experiments conducted in duplicate in a single laboratory, after 16 h of equilibration time and at a flow rate of 36 mL/h. Overall results showed good reproducibility (expressed in terms of the coefficient of variation, CV, calculated by dividing the standard deviation by the mean), as the CV was lower than 30% in more than 90% of the test results associated with Soil I. Moreover, low variability (expressed in terms of difference between the two test results divided by the mean) was observed in the test results related to Soils II and III, with a variability lower than 30% in more than 88% of the cases for Soil II and in more than 96% of the cases for Soil III. We also discussed the possible factors that affect the reproducibility and variability in the test results from the up-flow column percolation tests. The low variability inter and within laboratory obtained in this research indicates that the ISO/TS 21268-3 can be successfully upgraded to a fully validated ISO standard.

Characteristic pathological findings and effects of ecabet sodium in rat reflux esophagitis.

AIM: To explore the pathological findings in the entire esophagus in rats with reflux esophagitis, and the effects of ecabet sodium (ES). METHODS: A rat model of chronic acid reflux esophagitis was used. In the treatment group, ES was administered after surgery (n = 16). No drug was administered postoperatively to the esophagitis group (n = 9). Sham-operated rats were used as a control group (n = 5). Rats were sacrificed on day 7 after the operation. The epithelial thickness and leukocyte infiltration were examined in the upper, middle and lower areas of the esophagus. The survival rate, incidence of esophageal ulcer, and mean surface area and number of esophageal ulcers were determined in the esophagitis and ES groups. Esophageal histology was assessed in all three groups. RESULTS: Leukocyte infiltration in the esophagitis group was 26.3 +/- 22.0 in the middle esophagus and 8.2 +/- 4.9 in the upper esophagus, which was significantly greater than that in the controls (1.3 +/- 1.1 and 1.4 +/- 1.0, respectively) (P < 0.05). The thickness of the epithelium in the esophagitis group was 210.8 +/- 47.7 microm in the lower esophagus and 204.2 +/- 60.1 microm in the middle esophagus, which was significantly greater than that in the controls (26.0 +/- 5.5 and 21.0 +/- 6.5 microm, respectively) (P < 0.05). The mean number of ulcers per animal in the ES group in the entire esophagus was 5.4 +/- 2.5, which was significantly less than that in the esophagitis group (9.0 +/- 3.5) (P < 0.05). The epithelial thickness in the ES group was 97.5 +/- 32.2 microm in the lower esophagus, which was decreased compared with that in the esophagitis group (210.8 +/- 47.7 microm) (P < 0.05). CONCLUSION: Mucosal inflammation extended to the upper esophagus close to the hypopharynx. Our study suggested that ES may have a useful defensive role in reflux esophagitis.

Presence of vertebral fractures is highly associated with hiatal hernia and reflux esophagitis in Japanese elderly people.

OBJECTIVE: Recent studies have shown the correlation between vertebral fractures (VFs) and gastrointestinal disorders in postmenopausal women. The aim of this study was to assess the association between VFs and hiatal hernia (HH) and/or reflux esophagitis (RE) in our patient population of both men and women. METHODS: We analyzed retrospective data of 280 patients aged 60 years or older (140 men and 140 women, mean +/- SD 73.5 years +/-7.05) who had undergone upper gastrointestinal endoscopy and chest X-rays in our hospital from August 2005 to February 2006. We analyzed the correlation between the presence of VFs and the presence of HH and/or RE. RESULTS: The incidence of RE in this study was 13.9% (39/280) and that of HH was 30.0% (84/280). Among these patients, 12.1% (41/280) had VFs. The incidence of RE in patients with VFs was 24.4% (10/41) and without VFs was 12.1% (29/239), with the difference being significant between those with and without VFs (p<0.05). The incidence of HH in patients with VFs was 43.9% (18/41) and in those without VFs was 27.6% (66/239), p<0.05. We subdivided subjects into four groups: HH only group, RE only group, HH/RE group and neither condition present group. We compared the incidence of VFs among these groups. VFs were observed in 16.4% (11/67) of the HH only group, 13.6% (3/22) of the RE only group, 41.2% (7/17) of the HH/RE group and 11.5% (20/174) in the neither condition present group. There was a significant difference in the incidence of VFs between the HH/RE group and neither condition present group (p<0.05). CONCLUSION: The presence of VFs was significantly associated with the presence of either RE or HH. This association became more significant when HH and RE were present together in elderly Japanese people.

Diaphragm-like stricture in the duodenum in a patient with systemic sclerosis: unrelated to non-steroidal anti-inflammatory drug use.

A 59-year-old Japanese woman was diagnosed in 1998 with systemic sclerosis (SSc). The patient presented with a one-month history of postprandial vomiting prior to hospitalization. The patient underwent esophago-gastroduodenoscopy which revealed a diaphragm-like stricture in the second part of the duodenum in January 2004. Unexpectedly, the patient had not used NSAIDs for any long period of time. Retrospective endoscopic findings from 2000 showed the presence of duodenal circular erosions at the same site. This is the first report of a patient diagnosed with SSc who also presented with endoscopic evidence of a stricture of the duodenum, unrelated to NSAIDs.

Increased esophageal sensitivity to acid and saline in patients with nonerosive gastro-esophageal reflux disease.

GOALS: To investigate the features of nonerosive reflux disease (NERD). BACKGROUND: NERD is not considered as a milder form of erosive gastro-esophageal reflux disease (eGERD). Although the prevalence of NERD was reported to be high in our country, there have been very few studies about NERD. STUDY: We performed upper gastrointestinal endoscopy to confirm the diagnosis of GERD. The modified acid perfusion test and saline perfusion test were performed in 7 control subjects, 14 NERD, and 11 eGERD patients. The stimulus-response function to acid and saline was quantified by the duration of typical symptom perception (minutes), total sensory intensity rating (0 to 10), and the perfusion sensory score (SS), which was defined as the product of minutes and the sensory intensity rating. RESULTS: The mean value of SS by saline was 0 in control subjects, 12.0 in NERD patients, and 1.5 in eGERD patients (P<0.01 control vs. NERD, P<0.01 NERD vs. eGERD). The mean SS with acid was 0.9 in control subjects, 52.5 in NERD patients, and 23.0 in eGERD patients (P<0.01 control vs. NERD, control vs. eGERD, P<0.05 NERD vs. eGERD). A statistically significant association was shown between the acid and saline perfusion SSs with a correlation coefficient value of r=0.57 in the NERD group (P<0.05). CONCLUSIONS: Both eGERD and NERD, but especially NERD, exhibited esophageal hypersensitivity not only to acid but also saline perfusion, suggesting that hyperalgesia to acid and other factors (eg, psychologic and/or autonomic nerve disturbance) may play some roles in symptom generation in NERD.

Altered localization and expression of tight-junction proteins in a rat model with chronic acid reflux esophagitis.

BACKGROUND: The esophageal tight junction is responsible for the paracellular sealing of the epithelium. Alteration of the expression of tight-junction proteins plays crucial roles in the pathogenesis of some human diseases. The aim of this study was to investigate the distribution and expression pattern of tight-junction proteins in the esophageal mucosa of control rats and rats with reflux esophagitis. METHODS: Chronic acid reflux esophagitis was experimentally induced by operation in rats. The animals were killed on days 7 and 14 after the operation. The thickness of the mucosa and the 5-bromo-2-deoxyuridine (BrdU) labeling index were assessed. The expression pattern of the tight-junction proteins claudin 1-4 and occludin in the esophageal mucosa was investigated by immunofluorescence staining and Western blotting in the controls and esophagitis rats. RESULTS: In the esophagitis model, the thickness and BrdU labeling index increased with time. In control rats, claudin-1, -3, and -4 were localized on the cellular membranes of esophageal epithelial cells, mainly in the spinous and granular layers, while claudin-2 was not detected in any layer. Occludin was seen on the cellular membranes in all esophageal mucosal layers. In the esophagitis rats, the expression of claudin-1 was increased both in the plasma membrane and in the cytoplasm around the erosion in the spinous and granular layers. The expression of claudin-4 and occludin shifted to the cytoplasm from the plasma membrane in the spinous and granular layers. In contrast, the expression of claudin-3 was decreased in the spinous and granular layers. CONCLUSIONS: The localization and the expression patterns of tight-junction proteins were different in the controls and the rat esophagitis model. The expression of claudin-3 in the esophageal mucosa was decreased, while that of claudin-1 was increased. It is postulated that these alterations in tight-junction proteins most likely increase the permeability of the esophageal the epithelium, thereby impairing the defense mechanism of this epithelium.

Second-line treatment for Helicobacter pylori infection in Japan: proton pump inhibitor-based amoxicillin and metronidazole regimen.

BACKGROUND: Recent studies have reported that proton pump inhibitor (PPI)/amoxicillin (A) metronidazole (M) therapy for Helicobacter pylori infection provides a sufficient cure rate in Japan in patients who have failed first-line treatment with PPI/amoxicillin and clarithromycin (AC). To validate the efficacy of this regimen as second-line therapy, our experience with second-line treatment using a PPI/AM regimen was reviewed. METHODS: We analyzed data on 151 patients who had been prescribed a 10-day PPI/AM re-treatment regimen after eradication failure of 1 to 2 weeks' first-line PPI/AC therapy. The PPI/AM regimen was given according to results of susceptibility testing (S+) in 31 patients. The group that had undergone susceptibility testing was further divided into two subgroups according to dosage: standard dose of omeprazole (O)/AM (n = 11) and double dose of lansoprazole (L)/AM (n = 20). The PPI/AM regimen was given without susceptibility testing (S-) to 120 patients. These patients were also divided into two subgroups according to whether they received omeprazole or lansoprazole: OAM (n = 61) and LAM (n = 59). Cure rates and adverse effects in each group were analyzed. RESULTS: The intention-to-treat (ITT)-based cure rate with/without susceptibility testing was 93.5% (95% confidence interval [CI], 79%-99%) and 87.5% (95% CI, 80%-93%), respectively (not significant [NS]). The ITT-based cure rate in S+/S- for OAM and S+/S- for LAM was 90.9% (95% CI, 59%-100%)/82% (95% CI, 70%-91%), and 95% (95% CI, 75%-100%)/93.2% (95% CI, 84%-98%), respectively (NS). Adverse effects were seen in 26.3% and 32.5% of patients in the OAM group and the LAM group, respectively (NS). CONCLUSIONS: The 10-day PPI/AM re-treatment regimen is safe and effective, suggesting its usefulness as second-line treatment in Japan in patients who have failed initial treatment with the PPI/AC regimen.

Improvement of reflux symptoms 3 years after cure of Helicobacter pylori infection: a case-controlled study in the Japanese population.

BACKGROUND: Development of reflux esophagitis is one of the adverse effects that cause concern in relation to curative treatment of Helicobacter pylori infection. However, recent studies present a rather negative association between curative treatment and development of reflux esophagitis or reflux symptoms. Therefore, this issue has remained controversial. Accordingly, we investigated the long-term adverse effects of H. pylori eradication treatment in special reference to development of reflux symptoms. PATIENTS AND METHODS: We conducted a case controlled study by mailing structured questionnaires on past (before curative treatment or 3 years previously) and current status. A case was an endoscopically confirmed peptic ulcer patient with confirmed cure of the infection after eradication treatment 3 years previously and a control was one who had not undergone the eradication treatment during the same period. We studied 241 pairs who matched for age, gender, and type of ulcer disease (GU, DU or GDU). Of these pairs, 81.3% were male and the mean age was 52.6 +/- 9.6 year (range 23-76). RESULTS: The rates of patients with improved reflux symptoms in the case and control groups were 65.4% and 30.4%, respectively, with the rate being significantly greater in the case group. On the contrary, the rates of those with worsened reflux symptoms were similar (5.1% and 7.6%). Regarding general events, the rate of patients with decreased frequency of hospital visits and of those who regularly used antiacid medications were significantly decreased in the case group. Furthermore, the case group experienced significantly fewer hospital admissions for various diseases in this 3-year period. However, a significantly greater number of case group patients than control subjects gained weight. CONCLUSION: Reflux symptoms as well as general well-being were significantly improved after cure of H. pylori infection.

Inhibition of cell proliferation and induction of apoptosis by Helicobacter pylori through increased phosphorylated p53, p21 and Bax expression in endothelial cells.

Microcirculation plays a crucial role in mucosal physiological function as well as repair of gastric mucosal damage. Endothelial cell damage is known to disturb microcirculation and suppress angiogenesis. Therefore, the direct effect of Helicobacter pylori on endothelial cells in vitro was investigated with H. pylori water extract. The effect of H. pylori water extract on cell proliferation and apoptosis of human umbilical vein endothelial cells (HUVECs) was evaluated. The ratio of BrdU-positive HUVECs in both cagA/vacA-positive and -negative H. pylori water extract-treated groups was significantly lower at 24 h than that in the control group, but Escherichia coli water extract did not affect the proliferation of these endothelial cells. Apoptosis was induced by H. pylori water extracts after incubation for 24 h in a cagA/vacA-independent manner. In the mitochondrial permeability transition assay, tetramethylrhodamine methyl ester was accumulated in mitochondria of HUVECs. Western blot analysis showed no difference in the level of total p53 protein in H. pylori water extract-treated and non-treated cells, but the level of phosphorylated p53 protein was increased in the treated cells at 15 and 60 min after addition of the extract. Reverse transcription (RT)-PCR products for p21 and Bax were elevated in the H. pylori water extract-treated cells. p21 levels began to increase 0.5-1 h after addition of the extract, whereas Bax increased in the period 0.5-2 h. H. pylori induced a disturbance of cell proliferation and apoptosis in the vascular endothelial cells which may contribute to gastric mucosal injury and to delayed healing of gastric lesions.