Human cytomegalovirus (HCMV) is an opportunistic prototypic beta-herpesvirus that can cause severe and even fatal diseases in immune-naive newborns and immunocompromised adults. Host-virus interactions occurring at the transcriptional and posttranscriptional levels are critical for establishing an HCMV latent or lytic infection, but the mechanisms remain poorly understood. Herein, we investigated the expression of circRNAs in human leukemia monocytes (THP-1 cells) latently infected with HCMV and explored the diagnostic value of circRNAs in children with HCMV infection. A total of 2,110 and 1,912 circRNAs were identified in mock-infected and HCMV latent-infected THP-1 cells, respectively. Of these, we identified 1,421 differently expressed circRNAs, of which 650 were upregulated and 771 were downregulated. The host genes corresponding to the differentially expressed circRNAs were mainly involved in the regulation of host cell secretion pathways, cell cycle, and cell apoptosis. The differentially expressed circRNAs had binding sites for microRNAs, suggesting an important role in the mechanism of HCMV latent infection. Furthermore, a clinical analysis showed that the expression levels of hsa_circ_0001445 and hsa_circ_0001206 were statistically significantly different in HCMV-infected patients vs. normal controls, suggesting that these circRNAs could potentially serve as biomarkers of HCMV-infection.

Background The serum alanine aminotransferase (ALT) level is a critical parameter for evaluating liver injury in non‐alcoholic fatty liver disease (NAFLD). However, the currently accepted upper limits of normal (ULN) for serum ALT (ULN‐ALT) are debated, as they may be excessively high. Methods A total of 1638 children aged 6‐16 years, comprising 507 children with normal BMI (500 healthy children and 7 children with NAFLD), 199 overweight children, and 932 obese children, were included in the analysis. We re‐evaluated the ULN‐ALT in 500 healthy Chinese children using the 95th percentiles of serum ALT levels as revised ULN‐ALT. Fatty liver was identified by ultrasound examination. Results Significant positive correlations between serum ALT levels and body mass index (BMI) were detected in overweight boys ( r = .399, P < .001), obese boys ( r = .398, P < .001), and obese girls ( r = .392, P < .001). The prevalence percentages of NAFLD were 93.6%, 75.8%, and 37.9% in obese boys with serum ALT levels of >50, 25‐50, and ≤25 U/L and were 81.6%, 67.9%, and 20.6% in obese girls with serum ALT levels of >40, 20‐40, and ≤20 U/L, respectively. Conclusion Serum ALT levels significantly correlated with abnormal BMI values in children, suggesting a rigorous BMI threshold is needed to establish the cutoffs for serum ULN‐ALT in children. Besides, the revised serum ULN‐ALT can uncover mild liver injury in obese children with NAFLD.