Functional macrophages and gastrointestinal disorders

Macrophages(MΦ) differe ntiate from blood monocytes and participate in innate and adaptive immunity.Because of their abilities to recognize pathogens and activate bactericidal activities,MΦ are always discovered at the site of immune defense.MΦ in the intestine are unique,such that in the healthy intestine,they possess complex mechanisms to protect the gut from inflammation.In these complex mechanisms,they produce anti-inflammatory cytokines,such as interleukin-10 and transforming growth factor-β,and inhibit the inflammatory pathways mediated by Toll-like receptors.It has been demonstrated that resident MΦ play a crucial role in maintaining intestinal homeostasis,and they can be recognized by their unique markers.Nonetheless,in the inflamed intestine,the function of MΦ will change because of environmental variation,which may be one of the mechanisms of inflammatory bowel disease(IBD).We provide further explanation about these mechanisms in our review.In addition,we review recent discoveries that MΦ may be involved in the development of gastrointestinal tumors.We will highlight the possible therapeutic targets for the management of IBD and gastrointestinal tumors,and we also discuss why more details are needed to fully understand all other effects of intestinal MΦ.

Effect of entacapone on colon motility and ion transport in a rat model of Parkinson's disease

AIM: To study the effects of entacapone, a catecholO-methyltransferase inhibitor, on colon motility and electrolyte transport in Parkinson's disease(PD) rats.METHODS: Distribution and expression of catecholO-methyltransferase(COMT) were measured by immunohistochemistry and Western blotting methods. The colonic smooth muscle motility was examined in vitroby means of a muscle motility recording device. The mucosal electrolyte transport of PD rats was examined by using a short-circuit current(I SC) technique and scanning ion-selective electrode technique(SIET). Intracellular detection of c AMP and c GMP was accomplished by radioimmunoassay testing. RESULTS: COMT was expressed in the colons of both normal and PD rats, mainly on the apical membranes of villi and crypts in the colon. Compared to normal controls, PD rats expressed less COMT. The COMT inhibitor entacapone inhibited contraction of the PD rat longitudinal muscle in a dose-dependent manner. The β2 adrenoceptor antagonist ICI-118,551 blocked this inhibitory effect by approximately 67%(P < 0.01). Entacapone increased mucosal ISC in the colon of rats with PD. This induction was significantly inhibited by apical application of Cl- channel blocker diphenylamine-2, 2'-dicarboxylic acid, basolateral application of Na+-K+-2Cl-co-transporter antagonist bumetanide, elimination of Cl- from the extracellular fluid, as well as pretreatment using adenylate cyclase inhibitor MDL12330 A. As an inhibitor of prostaglandin synthetase, indomethacin can inhibit entacaponeinduced ISC by 45%(P < 0.01). When SIET was applied to measure Cl- flux changes, this provided similar results. Entacapone significantly increased intracellular c AMP content in the colonic mucosa, which was greatly inhibited by indomethacin.CONCLUSION: COMT expression exists in rat colons. The β2 adrenoceptor is involved in the entacaponeinduced inhibition of colon motility. Entacapone induces c AMP-dependent Cl- secretion in the PD rat.

Optimizing Data Collection Path in Sensor Networks with Mobile Elements

Exploiting mobile elements （MEs） to accomplish data collection in wireless sensor networks （WSNs） can improve the energy efficiency of sensor nodes, and prolong network lifetime. However, it will lead to large data collection latency for the network, which is unacceptable for data-critical applications. In this paper, we address this problem by minimizing the traveling length of MEs. Our methods mainly consist of two steps： we first construct a virtual grid network and select the minimal stop point set （SPS） from it; then, we make optimal scheduling for the MEs based on the SPS in order to minimize their traveling length. Different implementations of genetic algorithm （GA） are used to solve the problem. Our methods are evaluated by extensive simulations. The results show that these methods can greatly reduce the traveling length of MEs, and decrease the data collection latency.