Objective To analyze the nutrition status of primary and middle school students in Baodi district,Tianjin in 2021 and 2023,as to provide scientific basis for improving the nutritional status of students.Methods A stratified random cluster sampling method was adopted to select 12 schools in Baodi district,Tianjin.Students' nutrition status were assessed from September to November of every year in 2021 and 2023,including questionnaire survey,physical examination and biochemical indicators.Results Compared with the same gender and age students in 2021,the height of boys aged 7-13 and girls aged 7-12 will significantly increase in 2023,while the body mass of boys and girls aged 8 and 11 will significantly increase.Compared with 2021,the overweight and obesity rates among males have significantly decreased in 2023,while the emaciation rates among males and females have significantly increased.The anemia rate,serum ferritin and vitamin A,and vitamin D deficiency rate among students in 2023 were 12.25％,3.77％,15.70％,and 50.31％,respectively,with no statistically significant difference compared to 2021(P＞0.05).The awareness rate of nutrition knowledge and the proportion of related behaviors among students in 2023 have significantly increased compared to 2021.Conclusion Compared with 2021,the overweight and obesity rates among primary and secondary school students will decrease in 2023,while anemia,serum ferritin,vitamin A,and vitamin D deficiencies will not improve.Targeted intervention activities are urgently needed.

Objective To analyze the nutrition status of primary and middle school students in Baodi district,Tianjin in 2021 and 2023,as to provide scientific basis for improving the nutritional status of students.Methods A stratified random cluster sampling method was adopted to select 12 schools in Baodi district,Tianjin.Students' nutrition status were assessed from September to November of every year in 2021 and 2023,including questionnaire survey,physical examination and biochemical indicators.Results Compared with the same gender and age students in 2021,the height of boys aged 7-13 and girls aged 7-12 will significantly increase in 2023,while the body mass of boys and girls aged 8 and 11 will significantly increase.Compared with 2021,the overweight and obesity rates among males have significantly decreased in 2023,while the emaciation rates among males and females have significantly increased.The anemia rate,serum ferritin and vitamin A,and vitamin D deficiency rate among students in 2023 were 12.25％,3.77％,15.70％,and 50.31％,respectively,with no statistically significant difference compared to 2021(P＞0.05).The awareness rate of nutrition knowledge and the proportion of related behaviors among students in 2023 have significantly increased compared to 2021.Conclusion Compared with 2021,the overweight and obesity rates among primary and secondary school students will decrease in 2023,while anemia,serum ferritin,vitamin A,and vitamin D deficiencies will not improve.Targeted intervention activities are urgently needed.

Nucleic acid-based drugs, such as RNA and DNA drugs, exert their effects at the genetic level. Currently, widely utilized nucleic acid-based drugs include nucleic acid aptamers, antisense oligonucleotides, mRNA, miRNA, siRNA and saRNA. However, these drugs frequently encounter challenges during clinical application, such as poor stability, weak targeting specificity, and difficulties in traversing physiological barriers. By employing chemical modifications of nucleic acid structures, it is possible to enhance the stability and targeting specificity of certain nucleic acid drugs within the body, thereby improving delivery efficiency and reducing immunogenicity. Moreover, utilizing nucleic acid drug carriers can facilitate the transportation of drugs to lesion sites, thereby aiding efficient intracellular escape and promoting drug efficacy within the body. Currently, commonly employed delivery carriers include virus vectors, lipid nanoparticles, polymer nanoparticles, inorganic nanoparticles, protein carriers and extracellular vesicles. Nevertheless, individual modifications or delivery carriers alone are insufficient to overcome numerous obstacles. The integration of nucleic acid chemical modifications with drug delivery systems holds promise for achieving enhanced therapeutic effects. However, this approach also presents increased technical complexity and clinical translation costs. Therefore, the development of nucleic acid drug carriers and nucleic acid chemical modifications that are both practical and simple, while maintaining high efficacy, low toxicity, and precise nucleic acid delivery, has become a prominent research focus in the field of nucleic acid drug development. This review comprehensively summarizes the advancements in nucleic acid-based drug modifica-tions and delivery systems. Additionally, strategies to enhance nucleic acid drug delivery efficiency are discussed, with the aim of providing valuable insights for the translational application of nucleic acid drugs.
Nucleic Acids ; RNA, Small Interfering/genetics* ; Drug Carriers ; Drug Delivery Systems ; Drug Development