The other proposed mechanism has been called a "perigenetic pathway", and involves enhancement of the transformed host cell phenotype by means of alterations in cell proteins, such as adhesion proteins. H. pylori has been proposed to induce inflammation and locally high levels of TNF-α and/or interleukin 6 (IL-6). According to the proposed perigenetic mechanism, inflammation-associated signaling molecules, such as TNF-α, can alter gastric epithelial cell adhesion and lead to the dispersion and migration of mutated epithelial cells without the need for additional mutations in tumor suppressor genes, such as genes that code for cell adhesion proteins.The strain of H. pylori a person is exposed to may influence the risk of developing gastric cancer. Strains of H. pylori that produce high levels of two proteins, vacuolating toxin A (VacA) and the cytotoxin-associated gene A (CagA), appear to cause greater tissue damage than those that produce lower levels or that lack those genes completely. These proteins are directly toxic to cells lining the stomach and signal strongly to the immune system that an invasion is under way. As a result of the bacterial presence, neutrophils and macrophages set up residence in the tissue to fight the bacteria assault.H. pylori is a major source of worldwide cancer mortality. Although the data varies between different countries, overall about 1% to 3% of people infected with Helicobacter pylori develop gastric cancer in their lifetime compared to 0.13% of individuals who have had no H. pylori infection. H. pylori infection is very prevalent.
Difluprednate is a corticosteroid, It is chemically a butyrate ester of 6(alpha),9(alpha)-difluoro prednisolone acetate. Accordingly, difluprednate is sometimes abbreviated DFBA, for difluoroprednisolone butyrate acetate. Approval
On June 24, 2008, the US Food and Drug Administration (FDA) approved difluprednate for the treatment of post-operative ocular inflammation and pain. It is marketed by Alcon under the tradename Durezol. Clinical trials
Difluprednate ophthalmic emulsion 0.05% is also being studied in other ocular inflammatory diseases, including a phase 3 study evaluating difluprednate for the treatment of anterior uveitis


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