Epilepsy is a chronic brain dysfunction caused by the excessive synchronous firing of neurons.It is one of the common nervous system diseases in children.Repeated epileptic seizures often lead to physiological and inte-llectual damage in children, seriously affecting children′s growth, development and health.Previous studies have shown that there are significant differences in intestinal flora between epileptic and normal children.Intestinal flora participate in the development of epilepsy through multiple pathways, including the immune system, hypothalamic-pituitary-adrenal axis, neurotransmitters and vagus nerve.

Objective:To compare the characteristics and differences of intestinal flora in premature infants with late-onset sepsis (LOS) and pneumonia by high-throughput sequencing technology, and to investigate the relationship between intestinal flora and LOS.Methods:Through the case-control method, premature infants with late-onset sepsis who were hospitalized in the neonatal department of Hunan Children′s Hospital from August 2018 to October 2019 were selected as the case group ( n=8). At the same time, premature infants diagnosed with pneumonia were selected as the control group ( n=8). The fecal samples of 16 premature infants were collected for the first time, and the DNA was extracted. The DNA of the target region was amplified by polymerase chain reaction(PCR). High-throughput sequencing was performed using NovaSeq 6000 platform to analyze the composition and diversity of intestinal flora between the two groups. Results:(1) Alpha diversity analysis showed that there was no significant difference in the richness and diversity of intestinal flora between the two groups(all P>0.05). (2) The intestinal flora in premature infants of LOS group and control group were dominated by Firmicutes and Proteobacteria, and facultative anaerobes such as Enterococcus and Escherichia-Shigella were the dominant flora at the genus level. Metastas statistical analysis showed that there was no statistically significant difference in flora composition between the two groups at the phylum level ( P>0.05). (3) Metastas statistical analysis was carried out at the level of class, order, family, genus, and species. The relative abundance of actinomycetes, digestive streptococcaceae and Clostridium in LOS group was higher than that in pneumonia group, and the difference was statistically significant (all P<0.05). (4) The relative abundance of Staphylococcus in the LOS group was significantly greater than that in the control group, but Metastas statistical analysis showed that there was no statistically significant difference in the relative abundance of staphylococcus between the two groups ( P>0.05). (5) Among the 8 cases of LOS, 3 premature infants had positive blood cultures, namely Streptococcus agalactiae, Streptococcus mitis, and Enterococcus faecalis. Enterococcus faecalis belongs to the genus Enterococcus, and Enterococcus belongs to the dominant genus in the LOS group. Conclusions:Different site infections have effects on intestinal microecology of premature infants. There were differences in intestinal flora composition between premature infants with LOS and premature infants with pneumonia.

Objective:The purpose of this study was to analyze the expression profile of miRNAs in children with autism spectrum disorders (ASD), and to discuss the clinical significance of differentially expressed miRNAs.Methods:MiRNA microarray was used to analyze the expression of miRNA in peripheral blood of 3 pairs of ASD patients-healthy controls; 17 pairs of ASD patients-healthy controls were used to verify the differentially expressed miRNA; Receiver operating characteristic (ROC) curve was used to analyze the differential expression the value of miRNA in the diagnosis of ASD.Results:A total of 32 differentially expressed genes were screened by 3 pairs of miRNA microarray including 12 up-regulated miRNAs and 20 down-regulated miRNAs. miRNA verification of 20 differentially expressed miRNAs showed miR-15a-5p, miR-27a-3p , miR-142-3p and miR-142-5p were significantly down-regulated in children with ASD, with statistically significant difference (all P<0.05). ROC curve analysis showed that the area under the curve (AUC) of the above four miRNAs diagnosing ASD were all greater than 0.70, with sensitivities 94.12%, 100%, 100%, and 82.35%, respectively. Conclusions:The expression of miR-142-3p, miR-27a-3p/miR-15a-5p, and miR-142-5p is down-regulated in the peripheral blood of ASD patients, and has the potential as biomarkers for early screening of ASD.