Epigenetic modifications of 45S rDNA associates with the disruption of nucleolar organisation during Cd stress response in Pakchoi.

The role of the nucleolus in Pakchoi response to Cd stress remains largely unknown. In this work, we focus on exploring the underling mechanism between nucleolus disruption and epigenetic modification in Cd stressed-Pakchoi. Our results indicated that the proportion of nucleolus disruption, decondensation of 45 S rDNA chromatin, and a simultaneous increase in 5' external transcribed spacer region (ETS) transcription were observed with increasing Cd concentration, accompanied by genome-wide alterations in the levels of histone acetylation and methylation. Further results showed that Cd treatment exhibited a significant increase in H3K9ac, H4K5ac, and H3K9me2 levels occurred in promoter regions of the 45 S rDNA. Additionally, DNA methylation assays in the 45 S rDNA promoter region revealed that individual site-specific hypomethylation may be engaged in the activation of 45 S rDNA transcription. Our study provides some molecular mechanisms for the linkage between Cd stress, rDNA epigenetic modifications, and nucleolus disintegration in plants.

Comparison between Ibuprofen and Acetaminophen in the Treatment of Infectious Fever in Children: A Meta-Analysis.

Background: To evaluate ibuprofen and acetaminophen in the treatment of infectious fever in children. Methods: We searched randomized controlled trials and retrospective cohort studies comparing ibuprofen and acetaminophen in the treatment of infectious fever among children. Data were extracted from eligible studies. We sought to evaluate temperature after taking drugs in 1, 2, and 4 hours, respectively, and analyzed the adverse events. Results were expressed as mean difference(MD) and risk ratio (RR) with 95% confidence intervals. Results: Ten studies were included in this study with a total of 1773 patients. The results showed that acetaminophen had higher temperature than ibuprofen after 1 hour (The overall mean difference was -0.29 with 95% CI (-0.49, -0.09). The P value of the overall effect was = 0.004, I 2 = 91%), 2 hours (MD = -0.46, 95% CI (-0.67, -0.25), P < 0.00001, I 2 = 95%), and 4 hours (MD = -0.57, 95% CI (-0.82, -0.33), P < 0.00001, I 2 = 97%). There is no difference between two drugs in the adverse events (RR = 0.8, 95% CI (0.52, 1.24), P = 0.32, I 2 = 0%). The sensitivity analysis and funnel plot showed that our study was robust and had low publication bias. Conclusion: Our study suggested that ibuprofen is more effective than acetaminophen in children with infectious fever.