To investigate the association of Helicobacter pylori and gastric ulcer and adenocarcinoma, IgG antibodies against H. pylori were examined in 823 randomly selected subjects, 92 healthy volunteers, 117 patients with gastric ulcer, and 148 with gastric adenocarcinomas in Taiwan, where the prevalence of gastric adenocarcinoma is high. The seropositivity of this population in Taiwan was 54.4%. Gastric ulcer patients had a higher seropositivity (83.8%) than healthy volunteers (62.0%) and gastric adenocarcinoma patients (62.2%) (P < 0.001). Gender difference, blood type, and habit of smoking were not associated with the seroprevalence in any study groups. Gastric ulcer coexistent with duodenal ulcer had a higher seropositivity (94.7%) (P < 0.05). The seropositivity of H. pylori in gastric adenocarcinoma patients was higher than in healthy volunteers only in younger age and was not associated with histologic type, invasion, and location of major tumors. The results reemphasize the association of H. pylori infection with gastric ulcer but not with gastric adenocarcinoma in Taiwan.

A calcium phosphate cement, Grossman sealer, and Sargenti N2 were compared under conditions where root canals of monkey incisors were deliberately overfilled and the apical tissue responses were evaluated histologically. The periapical tissues exposed to Sargenti N2 revealed severe irritation at all times through the 6-month experimental period. The reactions to Grossman sealer were milder but persisted throughout the observation period. The calcium-phosphate-cement treated animals showed mild tissue irritation after 1 month, but thereafter the adverse tissue reactions were minimal. New bone formation adjacent to the cement was also observed. These results point to the possibility that calcium phosphate cement might be used in simplified endodontic procedures. The compatibility of calcium phosphate cement with the periapical tissue suggests that the cement may have other applications in dentistry and medicine.

We conclude that oral administration of immune milk leads to significant improvements of symptoms and signs in OSF patients.

Expression of ras p21 oncoproteins was examined in histological sections of oral squamous cell carcinoma (SCC), epithelial dysplasia, epithelial hyperkeratosis and normal oral mucosa using antibodies to ras p21 with an immunoperoxidase technique. Ras p21-positive staining was found in 47 of 51 (92.2%) cases of oral SCC, 4 of 4 (100%) cases of epithelial dysplasia, 7 of 7 (100%) cases of epithelial hyperkeratosis, and 1 of 6 (16.7%) cases of normal oral mucosa. The positive staining rate of ras p21 in oral SCC, epithelial dysplasia or epithelial hyperkeratosis was significantly higher than that in normal oral mucosa (P < 0.05). No correlation was found between ras p21 expression and patient age, tumour location, tumour size, clinical staging or histological differentiation of SCC. However, a significant positive correlation was found between ras p21 expression and patients' sex (P < 0.05) or regional lymph node status (P < 0.05). A significant positive correlation was also discovered between ras p21 expression and patients' smoking habits (P < 0.01), as well as daily or total betel quid (BQ) consumption (P < 0.05). Of the 47 immunostain-positive SCC patients, specimens from 6 patients were also obtained after chemotherapy, when ras p21 expression was found to be reduced. These results indicate that ras p21 overexpression may play an important role in the initiation and progression of oral SCCs in patients who are smokers and BQ chewers.