PM2.5 Synergizes With Pseudomonas aeruginosa to Suppress Alveolar Macrophage Function in Mice Through the mTOR Pathway.

High concentrations of PM2.5 in enclosed broiler houses cause respiratory disorders in humans and animals. Pseudomonas aeruginosa (P. aeruginosa) is an opportunistic pathogen that can induce severe respiratory disease in animals under stress or with abnormal immune functions. Alveolar macrophages are lung-resident immune cells that play important roles in lung host defence and immune balance. In this study, the mechanism by which PM2.5 synergizes with P. aeruginosa to damage alveolar macrophage function and induce inflammation was investigated. The results will provide a theoretical basis for improving the poultry breeding environment and preventing the recurrence of infection with P. aeruginosa. Alveolar macrophages were stimulated by PM2.5 collected in an enclosed broiler house and P. aeruginosa. Phagocytosis was determined by the neutral red test. The apoptosis rate and cytoskeleton changes were observed by flow cytometry assays and laser scanning confocal microscopy. Protein levels related to autophagy and the mTOR pathway were detected by Western blotting. The results indicated that PM2.5 in combination with P. aeruginosa could decrease phagocytosis, inhibit autophagy, increase apoptosis, and destroy the cytoskeleton in alveolar macrophages. In addition, alveolar macrophages had significantly increased expression of mTOR pathway-related proteins in response to the synergistic stimulation of PM2.5 and P. aeruginosa. The above results confirmed that PM2.5 in poultry houses synergized with P. aeruginosa to impede alveolar macrophage function and caused more severe respiratory system injuries through a process closely related to the activation of the mTOR signalling pathway.

Whole genome analysis of a novel adenovirus discovered from Oriolus chinesis.

We present the first complete genome sequence of an aviadenovirus Oriolus adenovirus (OrAdV) sequenced from the cloaca of a Oriolus chinensis (a passerine bird widely distributed in Asia), which was collected from an island off the east coast of China. Thirty-one protein coding genes were predicted in this 40425-bp-long genome. OrAdV genome is highly divergent and has only 57% average protein identity compared with other aviadenovirus genomes. Comparative genomic analysis indicates that this passerine virus is a new species of aviadenovirus. One unique thymidylate kinase gene was discovered in OrAdV genome. This gene is absent in other adenovirus genomes and usually reported to occur in herpesvirus. Protein sequence alignment against all known proteins indicates that this gene may be originated from ancient horizontal gene transfer event between virus and parasitic eukaryote like protozoan. This new aviadenovirus genome enriches the genomic information of adenovirus and suggests that there is a large unknown space of adenovirus world.

[Relation of miR-140 Expression Level with Therapeutic Effect of Decitabine and Its Mechanism].

OBJECTIVE: To investigate the relationship of miR-140 expression level with the therapeutic effect of decitabine, and to explore whether the molecular mechanism is dependent on the regulation of TLR4 expression. METHODS: Forty-seven patients with acute myeloid leukaemia (AML) were enrolled in our study and divided into decitabine combination treatment group (22 cases) and traditional treatment group (25 cases). The clinical efficacy was compared between these two groups. Real-time PCR was used to determine the plasma level of miR-140 in AML patients. Decitabine, miR-140 mimic and miR140 inhibitor were used to treat AML HL-60 cells in vitro, the real-time PCR and Western blot were used to detect the expressions of miR-140, TLR4 and NF-κB at both mRNA and protein levels. RESULTS: Compared with traditional treatment group, decitabine combination treatment group showed more significant clinical efficacy. Plasma miR-140 level in both 2 treatment groups both decreased, but the plasma miR-140 level was higher in decitabine combination treatment group as compared with traditional treatment group. Experiment in vitro showed that 0.3 µmol/L decitabine significantly inhibited the HL-60 cell proliferation accompanied by up-regulation of miR-140 expression and down-regulation of expression of TLR4 and NF-κB. These effects induced by decitabine were partly reversed by pretreating the cells with 200 nmol/L miR-140 inhibitor. CONCLUSION: Decitabine-induced up-regulation of miR-140 expression may be related with its chemotherapeutic effects, and miR-140/TLR4/NF-κB pathway may partly mediate the pharmacologic action of decitabine.