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Postoperative ileus (POI) is gastrointestinal motility dysfunction after abdominal surgery caused by mechanical stress to intestine. It occurs nausea and vomiting, and lead to lower QOL during hospitalization for patients. It is regarded as a problem because it costs medical expenses due to long hospitalization. The intestinal inflammation caused by macrophage and neutrophil is thought to be important of the mechanism of POI. In tissue injury or inflammation, adenosine triphosphate (ATP) is released from injured cell. Purinergic P2X7 receptor (P2X7R) is expressed on inflammatory cells and ATP induces the secretion of inflammatory mediators through P2X7R. P2X7R antagonist is thought to be important in the first step of inflammation, and it is confirmed that P2X7R antagonist showed anti-inflammatory effects in chemically-induced colitis models. Therefore, we hypothesized that P2X7R has important function in POI and examined the effect of P2X7R antagonist in mouse POI model. As a result, P2X7R antagonist A438079 ameliorated macrophage and neutrophil infiltration in POI. The impairment of intestinal transit was improved by P2X7R antagonist. It tended to ameliorate the increase of IL-6, IL-1β and TNF-α mRNA expression in intestinal muscularis caused by POI. P2X7R expressed on both infiltrated and resident macrophages in the inflamed ileal muscle layer. In conclusion, P2X7R antagonist showed the anti-inflammatory effect through P2X7R on macrophages, and it may be the target to treat POI.

IL-33 is a novel cytokine that is believed to be involved in inflammation and carcinogenesis. However, its source, its production and its secretion process remain unclear. Recently, we have reported that IL-33 is up-regulated in dextran sulfate sodium (DSS) colitis in mice.Production of IL-33 from intestinal tissue was studied in a murine cancer model induced by azoxymethane (AOM) and DSS in vivo and in cultures of IEC-6 epithelial cells. Cytokine levels were measured by real time PCR, immunohistochemistry and elisa.Mice with AOM/DSS-induced colitis expressed all the characteristic symptoms of colon cancer pathology. Immunohistochemical analysis demonstrated epithelial cell-derived IL-33 in colon tissues from mice with AOM/DSS colitis. Real time PCR and quantitative PCR analysis revealed that AOM/DSS colitis tissues expressed up-regulated IL-1β, IL-33, TGF-β, and EGF mRNA. Gefitinib, an EGFR inhibitor, inhibited IL-33 mRNA expression in AOM/DSS colitis mice. The pathophysiological role of IL-33 in the rat intestinal epithelial cell line (IEC-6 cells) was then investigated. We found that EGF, but not TGF-β1 or PDGF, greatly enhanced mRNA expression of IL-33 and its receptor ST2. In accordance with the gene expression and immunohistochemical analysis of IL-33 levels, elisa-based analysis of cytoplasmic and nuclear extracts showed increased IL-33 protein levels in IEC-6 cells after treatment with EGF.Our results suggest that EGF is a key growth factor that increased IL-33 production and ST2 receptor expression during intestinal inflammation and carcinogenesis. The EGF/IL-33/ST2 axis represents a novel therapeutic target in colon cancer.

This paper reports a stereolithography-like 3D fabrication method based on soft-lithography techniques. It only requires standard equipment for photolithography, but it makes true 3D structures fabrication possible. We developed a rotating partition by this method in a microfluidic channel, which cannot be achieved by conventional soft-lithography, and demonstrated a prototyping three-dimensional flow mixer.

This paper demonstrates electric generation from sound to minimize and integrate microfluidic systems for point of care testing or in-situ analysis. In this work, 5.4 volts and 50 mW DC was generated from sound through an earphone cable, which is a versatile system and able to actuate small size and low power consumption devices like an electro osmotic pump.