S100A8 and peptic ulcer disease: The cagA DNA sequences from the following amplicons were analyzed: 9 gastric cancer amplicons (MX02-C, MX21-C, MX22-C, MX05-C, MX12-C, MX03-C, MX08-C, MX17-C, MX16-C); 9 chronic gastritis amplicons (MX66-G, MX51-G, MX52-G, MX637-G, MX006-G, MX44-G, MX43-G, MX45-G, MX392-G) and two peptic ulcer amplicons (MX204-GU, MX327-GU).