Increased programmed death-ligand-1 expression in human gastric epithelial cells in Helicobacter pylori infection.

B7-H1 [programmed death-ligand-1 (PD-L1)] is a B7-family member that binds to programmed death-1 (PD-1). Recently, deficiency of PD-L1 has been demonstrated to result in accelerated gastric epithelial cell damage in gastritis, and PD-L1 is suggested to play a critical role in regulating T cell homeostasis. Here, we aimed to gain more insight into gastric PD-L1 expression, regulation and function during Helicobacter pylori infection. PD-L1 expression in human gastric epithelial cells was analysed using Western blotting, quantitative polymerase chain reaction and fluorescence activated cell sorter analysis. Furthermore, co-culture experiments of human gastric epithelial cells with primary human T cells or Jurkat T cells were conducted. PD-L1 expression in primary human gastric epithelial cells was strongly enhanced by H. pylori infection and activated T cells, and augmented markedly by further stimulation with interferon-γ or tumour necrosis factor-α. Moreover, PD-L1 expression in gastric epithelial cells significantly induced apoptosis of T cells. Our results indicate that a novel bidirectional interaction between human gastric epithelial cells and lymphocytes modulates PD-L1 expression in human gastric epithelial cells, contributing to the unique immunological properties of the stomach.

Biodegradability of chlorophenol wastewater enhanced by solar photo-Fenton process.

The combination of solar irradiation and Fenton reagent have been used to enhance the biodegradability (BOD(5)/COD) of chlorophenol wastewater, including 2-chlorophenol (2-CP), 4-chlorophenol (4-CP), and 2,4-dichlorophenol (2,4-DCP). Results showed that the solar photo-Fenton process improved significantly the biodegradability of chlorophenol wastewater. Basically, increasing initial H(2)O(2) dosage was much more beneficial for increasing biodegradability of wastewater than increasing initial Fe(2 + ) dosage. Among the conditions studied, the optimum condition of increasing biodegradability of chlorophenol wastewater was found with a [H(2)O(2)](0)/[Fe(2 + )](0)/[chlorophenol](0) ratio of 10.0/0.2/1.0, 10.0/0.3/1.0, and 10.0/0.2/1.0 for 2-CP, 4-CP, and 2,4-DCP, respectively. As a result, the value of BOD(5)/COD was increased from 0 for untreated solution up to 0.231, 0.248, and 0.193 for 2-CP, 4-CP, and 2,4-DCP, respectively with a 15-min treatment. Under the operation of optimum conditions, the oxidative state of chlorophenol wastewater could be easily controlled into a higher biodegradability stage. The COD and TOC degradation efficiency could be in excess of 90% on the whole as the preoxidized chlorophenol solution was treated by a following batch-type biological unit. In the meanwhile, the microtoxicity of wastewater reduced more than 95%.

Eosinophilic Gastroenteritis : Brief Review.

Eosinophilic gastroenteritis (EGE) is a rare disease which belongs to primary eosinophilic gastrointestinal disorders (primary EGIDs), characterized by an accumulation of eosinophils in the gastrointestinal (GI) tract and is strongly associated with atopy and allergy. The clinical presentations vary depending on the site and depth of eosinophilic intestinal infiltration. Radiology pictures may show irregular thickening of the folds, but these findings can also be present in other conditions like inflammatory bowel disease and lymphoma. The endoscopic appearance is also nonspecific. The definite diagnosis requires biopsy for histological evidence of GI eosinophilic infiltration and clinicians make the diagnosis in correlation with and by exclusion of other possible causes of eosinophilic infiltration. Because EGE is a rare disease, the treatment is based on limited case reports and clinicians' experience. Corticosteroids are the mainstay of therapy. The prognosis of EGE is relatively good when patients receive timely and proper treatment.