Objective: To explore the association between digital devices usage and body weight overestimation in children and adolescents aged 7-18, in order to provide a scientific basis for body weight overestimation prevention in children and adolescents. Methods: Based on the data of the Research Special Project for Public Welfare Industry of Health using stratified cluster sampling method in 2012, a tatal of 40 073 children and adolescents from 7 provinces with complete information were chosen. Ordinal multivariable Logistic regression model estimated the association between digital devices usage and body weight overestimation. Results: A total of 4 276(11.8%) students with overestimation of body weight were detected, who spent >300 min/d time in digital devices(5.12%) than others (3.84%)( χ 2=19.14, P <0.01). Univariate analysis showed that students with time spent on digital devices >300 min/d had a higher risk in overestimation of body weight ( OR=1.36,95%CI=1.18-1.57,P <0.01) compared with students who spent on digital devices≤120 min/d. There was still a significant association after confounder adjustment ( OR=1.28, 95%CI= 1.10-1.48,P <0.05). Stratified analysis showed that the association between digital devices usage and overestimation of body weight were only observed in girls, 11-18 years old and non single child( P <0.05). Conclusion The time usage of digital devices is associated with overestimation of body weight in children and adolescents. It may helpful for children and adolescents to prevent overestimation of body weight by reducing time spent on digital devices.

During the gene editing process mediated by CRISPR/Cas9, precise genome editing and gene knock-in can be achieved by the homologous recombination of double-stranded DNA (dsDNA) donor template. However, the low-efficiency of homologous recombination in eukaryotic cells hampers the development and application of this gene editing strategy. Here, we developed a novel CRISPR/Cas9-hLacI donor adapting system (DAS) to enhance the dsDNA-templated gene editing, taking the advantage of the specific binding of the LacI repressor protein and the LacO operator sequence derived for the Escherichia coli lactose operon. The codon-humanized LacI gene was fused as an adaptor to the Streptococcus pyogenes Cas9 (SpCas9) and Staphylococcus lugdunensis Cas9 (SlugCas9-HF) genes, and the LacO operator sequence was used as the aptamer and linked to the dsDNA donor template by PCR. The Cas9 nuclease activity after the fusion and the homology-directed repair (HDR) efficiency of the LacO-linked dsDNA template were firstly examined using surrogate reporter assays with the corresponding reporter vectors. The CRISPR/Cas9-hLacI DASs mediated genome precise editing were further checked, and we achieved a high efficiency up to 30.5% of precise editing at the VEGFA locus in HEK293T cells by using the CRISPR/SlugCas9-hLacI DAS. In summary, we developed a novel CRISPR/Cas9-hLacI DAS for dsDNA-templated gene editing, which enriches the CRISPR/Cas9-derived gene editing techniques and provides a novel tool for animal molecular design breeding researches.
Humans ; Animals ; Gene Editing ; CRISPR-Cas Systems/genetics* ; HEK293 Cells ; Homologous Recombination ; DNA