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In this study, styrene-(ethylene-co-butylene)-styrene (SEBS) triblock copolymer (Kraton G-1652) was modified with maleic anhydride (MA). The maleated SEBS was used as compatibilizer for the blends of Nylon 6 (PA6) and SEBS. The morphology and impact strength of the blends were measured as functions of concentration and MA graft ratio of maleated SEBS. The compatibility and fracture mechanism of the blends were evaluated from the SEM micrographs of the xylene-etched surfaces and of fractured surfaces. Some of the blends exhibited an impact strength up to about 30 fold greater than neat PA6. The fracture involved both cavitation and shear yielding. The mechanism of compatibilization of maleated SEBS in the ternary components blends was proposed.

Electron-impact ionization, laser-desorption ionization and collision-induced dissociation were used to investigate the fragmentation of the melamine (2,4,6-triamino-s-triazine) molecule and its deuterated counterparts. The dissociation of melamine was found to be different from the concerted triple dissociation pathway of s-triazine. The fragmentation of melamine was found to proceed through internal conversion to its ground potential energy surface before dissociation.

Aim: To elucidate the relations between the myeloperoxidase (-468)G-->A polymorphism and the development of duodenal ulcer (DU), and to investigate the impacts of this host genetic polymorphism on the histopathological features of Helicobacter pylori (H pylori)-related gastritis., Methods: In a case-control study of 115 consecutive DU patients and 182 controls, the myeloperoxidase (-468)G-->A polymorphism was genotyped. Additionally, gastric mucosal changes were examined according to the updated Sydney System., Results: The two study groups differed in the distributions of myeloperoxidase genotypes (P = 0.008). All six individuals carrying myeloperoxidase A/A genotypes were in the DU group. The carriage of myeloperoxidase allele A and H pylori infection were associated with an increased risk of DU with odds ratios (OR) of 2.3 and 5.8, respectively. The combined risk of the carriage of myeloperoxidase allele A and H pylori infection for DU was 8.7 (95% CI, 3.5-21.8). In the H pylori-infected individuals, allele A carriers displayed higher bacterial density scores (P = 0.04) in the antrum than did non-carriers., Conclusion: This work verifies for the first time the association of myeloperoxidase (-468)G-->A polymorphism with antral H pylori density and DU disease. The mechanisms underlying this genetic polymorphism in developing DU disease merit further investigations.

Aim: The role of intravenous pantoprazole in treatment of patients with high-risk bleeding peptic ulcers following endoscopic hemostasis remains uncertain. We therefore conducted the pilot prospective randomized study to assess whether intravenous pantoprazole could improve the efficacy of H(2)-antagonist as an adjunct treatment following endoscopic injection therapy for bleeding ulcers., Methods: Patients with active bleeding ulcers or ulcers with major signs of recent bleeding were treated with distilled water injection. After hemostasis was achieved, they were randomly assigned to receive intravenous pantoprazole or ranitidine., Results: One hundred and two patients were enrolled in this prospective trial. Bleeding recurred in 2 patients (4%) in the pantoprazole group (n = 52), as compared with 8 (16%) in the ranitidine group (n = 50). The rebleeding rate was significantly lower in the pantoprazole group (P = 0.04). There were no statistically significant differences between the groups with regard to the need for emergency surgery (0% vs 2%), transfusion requirements (4.9+/-5.9 vs 5.7+/-6.8 units), hospital days (5.9+/-3.2 vs 7.5+/-5.0 d) or mortality (2% vs 2%)., Conclusion: Pantoprozole is superior to ranitidine as an adjunct treatment to endoscopic injection therapy in high-risk bleeding ulcers.

Background: Recent studies suggest that cetraxate possesses anti-Helicobacter pylori (H. pylori) activity. We therefore conducted this pilot study to investigate the efficacy of a cetraxate-based triple therapy and to compare the regimen with proton pump inhibitor-based triple therapy., Methods: From April 2001 to January 2002, a total of 58 H. pylori-infected patients were randomly assigned to 1 of 2 regimens for 1 week: cetraxate plus clarithromycin and amoxicillin (CCA group) or pantoprazole plus clarithromycin and amoxicillin (PCA group). Follow-up endoscopy was performed at 8 weeks after the end of treatment to assess the treatment response., Results: Intention-to-treat analysis showed that the eradication rates of the CCA group (n = 27) and PCA group (n = 31) were 70.4% and 93.5%, respectively. The CCA group had a significantly lower eradication rate than the PCA group (p = 0.03). Per-protocol analysis also showed similar results (69.2% vs. 96.7%, p = 0.01). However, the frequency of adverse events in the CCA group was lower than that of the PCA group (3.7% vs. 25.8%, p = 0.03). Univariate analysis showed that the eradication rate was significantly related to proton pump inhibitor therapy (93.5% vs. 70.4%, p = 0.03 ) and smoking habit (66.7 % vs. 88.4%, p = 0.05), but multivariate analysis disclosed that proton pump inhibitor therapy was the only independent factor predicting treatment success (p < 0.05)., Conclusions: Cetraxate-based triple therapy is less effective than pantoprazole-based triple therapy in the treatment of H. pylori infection. However, the former has a lower frequency of adverse effects than the latter.