Long-term follow-up of gastric metaplasia after eradication of Helicobacter pylori

Backgrounds and Aims : There is no commonly accepted view concerning changes in gastric metaplasia after the eradication of Helicobacter pylori. The aim of this study was to evaluate the long-term course of gastric metaplasia after the eradication of this bacterium. Methods : The subjects were 59 patients with duodenal ulcer who were positive for Helicobacter pylori. Forty patients were classified as the eradication group. Gastric metaplasia was endoscopically and histologically evaluated before and after eradication of this bacterium. The follow-up period was 2-7.1 years. In the other 19 patients in the non-eradication group, gastric metaplasia was evaluated before and after treatment of the ulcer. Gastric metaplasia was evaluated in terms of its extent and type in all patients. Results : Gastric metaplasia showed the incomplete type before eradication but changed to the complete type after eradication, which persisted for a long period. The extent of gastric metaplasia increased after eradication. In the non-eradication group, gastric metaplasia infrequently changed to the complete type during the scarring period of ulcer. Conclusion : Gastric metaplasia changed to the complete type after the eradication of Helicobacter pylori, which persisted for a long period

Characteristics of Suppressor Macrophages Induced by Mycobacterial and Protozoal Infections in relation to Alternatively Activated M2 Macrophages

In the advanced stages of mycobacterial infections, host immune systems tend to change from a Th1-type to Th2-type immune response, resulting in the abrogation of Th1 cell- and macrophage-mediated antimicrobial host protective immunity. Notably, this type of immune conversion is occasionally associated with the generation of certain types of suppressor macrophage populations. During the course of Mycobacterium tuberculosis (MTB) and Mycobacterium avium-intracellulare complex (MAC) infections, the generation of macrophages which possess strong suppressor activity against host T- and B-cell functions is frequently encountered. This paper describes the immunological properties of M1- and M2-type macrophages generated in tumor-bearing animals and those generated in hosts with certain microbial infections. In addition, this paper highlights the immunological and molecular biological characteristics of suppressor macrophages generated in hosts with mycobacterial infections, especially MAC infection