Construction of immune/Creutzfeldt-Jakob disease-related gene coexpression network to predict biomarkers.

BACKGROUND AND PURPOSE: Creutzfeldt-Jakob disease (CJD) is a transmissible spongiform encephalopathy characterized by rapid onset and high mortality. Despite considerable progress in the treatment and diagnosis of CJD, patient prognosis remains poor. Many studies have found that the immune response is associated with the pathophysiology of CJD. However, few studies have reported coexpression correlations between genes associated with CJD and the immune response. This study was undertaken to construct a network of coexpressed immune- and CJD-related genes that may reveal new biomarkers and therapeutic targets for CJD. METHODS: Gene expression data from 11 CJD patients and 10 nonneurological controls were obtained from the Gene Expression Omnibus database. High-confidence protein-protein interaction (PPI) data were downloaded from the Human Protein Reference Database, and gene expression data of immune- and CJD-associated genes were downloaded from the AmiGo16 and DisGeNET databases, respectively. An immune/CJD-related expression network was constructed based on Pearson correlation coefficients and PPI networks, and a CJD-directed neighbour coexpression network was extracted, in which we compared the gene expression patterns and correlations between different groups. The samples were classified using CJD-specific modules, and differentially expressed genes (DEGs) between the CJD and nonneurological controls groups were identified within the CJD-specific modules. Further functional analysis was performed using Kyoto Encyclopaedia of Genes and Genomes (KEGG) enrichment analysis of genes in each CJD-specific module. RESULTS: We constructed an immune/CJD-related coexpression gene network comprising 2007 nodes and 5268 edges, with immune-associated genes occupying important positions in the network. In the CJD-directed neighbour coexpression network, immune-associated genes exhibited the highest coexpression level with their interacting genes. Results from Pearson correlation analysis showed that most of the CJD-associated genes were positively correlated with immune-associated genes. Screening for CJD-specific modules identified MAPK1, CASP3, APP, MAPT, SNCA, and YWHAH, indicating a close connection between CJD and the immune response. Analyses of coexpression status and expression level of CJD-specific genes revealed a very high coexpression pattern for any two genes, with most genes being DEGs. Finally, KEGG enrichment analyses of all CJD-specific genes showed that the pathophysiology of CJD is closely related to infection and the immune response. CONCLUSIONS: Our coexpression network analysis revealed a close connection between CJD- and immune-associated genes, and we identified six CJD-specific modules. Biological function analysis of CJD-specific module genes revealed that immune responses are associated with CJD pathophysiology and may provide novel diagnostic and therapeutic biomarkers for this disease.

[Effect of PM_(2. 5) on respiratory tract flora in SHR/NCrl rats].

OBJECTIVE: To investigate the effect of PM2. 5on the respiratory tract flora in the SHR / NCrl rats. METHODS: Through the simulation of real air pollution and mixed gas exposure, the establishment of acute exposure to air pollution in low, medium and high concentration of animal models, to detect the distribution of bacterial flora before and after the dust exposure in the throat and respiratory mucosa of SHR rats. Analysis on the trend of micro ecology of respiratory tract was studied dynamically. RESULTS: The detection rate of anaerobic bacteria in SHR rats was 71. 8% and 20. 7% respectively, compared with the previous exposure to dust was high than 0. 6%, there were significant differences( P <0. 05). In the detection rate of anaerobic bacteria, the Tetanus bacillus and Clostridium in the respiratory tract of the exposed to dust rats was not detected. After the dust exposure, two kinds of bacteria respectively in 28 and 5 SHR rats were detected. The detection rate ofVeillonella in anaerobic bacteria was 53. 1%, there were significant differences( P <0. 05). The number of pathogenic bacteria in the aerobic bacteria after the dust exposure was increased, the detection rate also increased. The results showed that in the body the number and species of bacteria after the exposure to dust were changed. CONCLUSION: PM_(2. 5) as the carrier of harmful substance, when with breathing enter the human respiratory tract, will cause the normal flora in the body 's respiratory tract disorder. The pathogen bacteria is easy to be colonized and the detection rate is increased, which affecting the body healthy.