Objective To investigate the infectious rates of 9 common pathogens and epidemiology in children with acute respira‐tory tract infections(ARI) in Maoming district .Methods The serum were collected from 6 241 children with acute respiratory in‐fection .IgM of 9 common pathogen including Mycoplasma pneumoniae (MP) ,Legionella pneumophila (LP) ,Coxiella burnetii (C .burnetii) ,Chlamydophila pneumoniae(CP) ,adenovirus(ADV) ,respiratory syncytial virus(RSV) ,type A and type B influenza virus(INFA and INFB) ,and parainfluenza virus(PIVS) ,were detected using immunofluorescence assay .Results Among 6 241 ca‐ses ,1 320 showed atypical pathogens infection ,and infection rate was 21% .The positive rate of MP was 15 .12% ,the highest infec‐tious pathogen;followed by the positive rate of INFB ,LP ,ADV and PIVS were 3 .03% ,1 .92% ,0 .54% and 0 .22% respectively . The pathogens with the lowest positive rate were RSV ,COX ,INFA and CP ,their infectious rates were 0 .14% ,0 .11% ,0 .048%and 0 .016% respectively .Conclusion The infection rate of atypical pathogen among children is high in this area ,which should be taken seriously .MP is the most common pathogen in children with ARI in Maoming district .The pathogen positive rate has rela‐tionship with season .

Purpose: Mixed-lineage leukemia protein 4 (MLL4/KMT2D) is a histone methyltransferase, and its mutation has been reported to be associated with a poor prognosis in many cancers, including lung cancer. We investigated the function of MLL4 in lung carcinogenesis. Materials and Methods: RNA sequencing (RNA-seq) in A549 cells transfected with control siRNA or MLL4 siRNA was performed. Also, we used EdU incorporation assay, colony formation assays, growth curve analysis, transwell invasion assays, immunohistochemical staining, and in vivo bioluminescence assay to investigate the function of MLL4 in lung carcinogenesis. Results: We found that MLL4 expression was downregulated in non–small cell lung cancer (NSCLC) tissues compared to adjacent normal tissues and tended to decrease with disease stage progression. We analyzed the transcriptomes in control and MLL4- deficient cells using high-throughput RNA deep sequencing (RNA-seq) and identified a cohort of target genes, such as SOX2, ATF1, FOXP4, PIK3IP1, SIRT4, TENT5B, and LFNG, some of which are related to proliferation and metastasis. Our results showed that low expression of MLL4 promotes NSCLC cell proliferation and metastasis and is required for the maintenance of NSCLC stem cell properties. Conclusion Our findings identify an important role of MLL4 in lung carcinogenesis through transcriptional regulation of PIK3IP1, affecting the PI3K/AKT/SOX2 axis, and suggest that MLL4 could be a potential prognostic indicator and target for NSCLC therapy.