Disrupted gastrointestinal (GI) motility is highly prevalent in patients with inflammatory bowel disease (IBD), but its potential causative role remains unknown. Herein, the role and the mechanism of impaired GI motility in colitis pathogenesis are investigated. Increased colonic mucosal inflammation is found in patients with chronic constipation (CC). Mice with GI dysmotility induced by genetic mutation or chemical insult exhibit increased susceptibility to colitis, dependent on the gut microbiota. GI dysmotility markedly decreases the abundance of Lactobacillus animlalis and increases the abundance of Akkermansia muciniphila. The reduction in L. animlalis, leads to the accumulation of linoleic acid due to compromised conversion to conjugated linoleic acid. The accumulation of linoleic acid inhibits Treg cell differentiation and increases colitis susceptibility via inducing macrophage infiltration and proinflammatory cytokine expression in macrophage. Lactobacillus and A. muciniphila abnormalities are also observed in CC and IBD patients, and mice receiving fecal microbiota from CC patients displayed an increased susceptibility to colitis. These findings suggest that GI dysmotility predisposes host to colitis development by modulating the composition of microbiota and facilitating linoleic acid accumulation. Targeted modulation of microbiota and linoleic acid metabolism may be promising to protect patients with motility disorder from intestinal inflammation.

The composition spatial distribution and degradation properties of dissolved organic matter (DOM) in Micro Pressure Inner Loop bioreactor (MPR) at low temperature were analyzed by fluorescence excitation-emission matrix regional integration analysis (EEM-FRI) and ultraviolet spectroscopy (UV). The results showed that MPR had a good degradation effect on DOM in low temperature municipal sewage and the upper region can degrade high molecular weight DOM. At low temperature, the fluorescence components of DOM at different sites were not different, and there were tryptophan-like Peak T1 and Peak T2, but the fluorescence intensity of the same components was different. The content of aromatic protein-like substance in MPR was higher, the microbial metabolism and humic acid in sewage treatment process were lower and these fluorescent components were evenly distributed.

Mast cells (MCs) are abundantly distributed in the human intestinal mucosa and submucosa. However, their roles and mechanisms in the development of colorectal cancer (CRC) are still unclear. In the present research, we found that the infiltration density of MCs in CRC tissues was positively correlated with improved patients’ prognoses. Moreover, MCs suppressed the growth and induced the apoptosis of CRC cells in vitro and in vivo but had no effect on normal colonic epithelial cells. The present study revealed that MCs specifically induced endoplasmic reticulum stress (ERS) and activated the unfolded protein response (UPR) in CRC cells but not in normal cells, which led to the suppression of CRC development in vivo. Furthermore, we found that the secreted Cystatin C protein was the key factor for the MC-induced ERS in CRC cells. This work is of significance for uncovering the antitumor function of MCs in CRC progression and identifying the potential of CRC to respond to MC-targeted immunotherapy.

Polystyrene (PS) foam is one of the main plastic materials dispersed in the environment. In this study, we observed that the insect-super mealworms (Zophobas morio), which belong to a species of the Tenebrio genus, are able to consume and degrade PS foam. Individual Z. morio consumed an extracellular polymeric substance (EPS) over 50 days with high survival rates. Analyses of the frass egested using fourier transform infrared spectroscopy (FTIR) confirmed the formation of a new oxygen-bearing functional group in the EPS. Gel permeation chromatography (GPC) analyses indicated that the depolymerization of ingested EPS with decreases in both Mw and Mn was observed, suggesting that the EPS was biodegraded. We also used 16S rRNA gene sequences to analyze the gut bacteria of Z. morio under three different feeding conditions, including with polystyrene, bran, and bran plus polystyrene. Under different dietary conditions, the gut microbiota of Z. morio showed significant differences, such as Klebsiella and Citrobacter becoming significantly enriched. In vitro studies using 90-days gut microbial culturing experiments indicated that gut microbiota contributed to PS degradation. Our research demonstrates that intestinal bacteria played an essential role in the degradation of PS by Z. morio, and provides a new theoretical basis and application ideas for the biodegradation of PS.

The morphology and surface characteristics of yeast cells have important impacts on a yeast-wastewater treatment system. In this study, the effects of supplement of Ca2+, Mn2+, Mg2+, NH4 + on settle ability, flocculation ability, hydrophobicity and morphology of cells of Candida tropicalis (O2) and Candida lipolytica (G1) were investigated. Result shows that: the effects of different nutrient factors on cell properties vary with yeast srains, The deficiency of Mg2+ can induce G1 to transform to the hyphal morphology which probably deteriorates the cell's settle ability, There is no manifest influence of Ca2+ and Mn2+ on settle ability and hydrophobicity of yeast cells. Whereas, to a certain extent, Ca2+ and Mn2+ inhibit the flocculation ability of O2 and G1. Addition of NH4 + can apparently enhance the growth, as well as germination, and hydrophobicity of yeast cells.