Background: Maternal tobacco exposure during pregnancy is known to cause a potential hazard to the offspring's health. So far, published studies have shown no consistent results with whether tobacco exposure in utero is causally linked to the development of allergic rhinitis in offspring. The aim of this study was to comprehensively evaluate the association between maternal tobacco exposure during pregnancy and allergic rhinitis in offspring by meta-analysis and to provide reference for clinical work. Methods: Literatures were searched in CNKI, Wanfang Data, VIP, SinoMed, PubMed, Web of science and Embase up to September 30,2020. Screening, inclusion, quality assessment, data extraction and data analysis of the literatures were conducted. Meta-analysis was performed with Revman 5.3 and State15.1 software. Odds ratio (OR) and 95%CI were used as observation indicators. Results: We had retrieved 16 articles with 22 independent datasets and 11,49,879 sample size. When all the studies were analyzed together, the results showed that maternal smoking exposure during pregnancy would increase the risk of allergic rhinitis in offspring (OR = 1.13, 95%CI:1.02–1.26), especially maternal passive smoking during pregnancy (OR = 1.39, 95%CI:1.05–1.84). But subgroup analysis showed that maternal active smoking during pregnancy was only significantly associated with offspring allergic rhinitis in cross-sectional studies (OR = 1.24, 95%CI:1.07–1.45) and study done in America study (OR = 1.22, 95%CI:1.05–1.42). Conclusions: Tobacco exposure during pregnancy could increase the risk of allergic rhinitis in offspring. The importance of avoiding prenatal tobacco exposure should be emphasized more for the health of next generation in the public.

Multiple evidence indicates that perinatal factors make impact on immune development and affect offspring allergic rhinitis (AR) risk. In this systematic review and meta-analysis, we examined available published studies to clarify the relationship between cesarean section (C-section) and offspring AR in children. To explore the relationship between C-section, especially the special attention was paid to different cesarean delivery mode, and the risk of AR in children. Articles were searched using PubMed, Web of Science, EMBASE, Cochrane Library, China knowledge Network, Wanfang, and China Science and Technology Journal databases. A meta-analysis of 22 studies published before August 1, 2022, which included 1,464,868 participants, was conducted for statistical analysis with RevMan5.4. The correlation strength between C-section and offspring AR was determined by combining odds ratio (OR) and 95% confidence interval (95% CI). Meta-regression and subgroup analyses were used to explore potential sources of heterogeneity. Publication bias was detected using the funnel chart and Egger tests. Meta-analysis revealed that there was a significant correlation between C-section and children AR (OR = 1.19, 95% CI: 1.12–1.27, P < 0.001), especially C-section with a family history of allergy (OR = 1.82, 95% CI: 1.36–2.43, P < 0.001). Moreover, elective C-section (without genital tract microbe exposure) had the higher risk of offspring AR (OR = 1.24, 95% CI: 1.05–1.46, P = 0.010) compared with the whole study. Meta-regression demonstrated that sample size explained 38.0% of the variability between studies, and year of publication explained 18.8%. Delivery by C-section, particularly elective C-section and C-section with a family history of allergy can increase the risk of AR in children.

New perspectives on angiotensin-converting enzyme 2 and its related diseases

Objective: The purpose of this study was to provide evidence for early life care by meta-analyzing the relationship between infection during pregnancy and up to 2 years of age and the risk of subsequent allergic rhinitis (AR). Methods: Published studies up to April 2022 were systematically searched in PubMed, Embase, Web of Science, Cochrane Library, SinoMed, CNKI, Wanfang Database, and VIP. Literature screening, including quality assessment, was performed, and the effect values (OR, HR, RR) and 95% confidence intervals (95% CI) of infection during pregnancy and up to 2 years of age and allergic rhinitis were extracted from each qualified study. Results: In total, 5 studies with a sample size of 82,256 reported the relationship between infection during pregnancy and offspring AR. Meta-analysis showed that maternal infection during pregnancy was associated with an increased risk of childhood AR in offspring (OR = 1.34, 95% CI: 1.08–1.67). Altogether, 13 studies with a sample size of 78,426 reported evidence of an association between infection within 2 years of age and subsequent AR in children. A pooled meta-analysis of all studies showed that early infection within 2 years of age was closely associated with childhood AR (OR = 1.25, 95% CI: 1.12–1.40), especially upper respiratory tract infection (OR = 1.32, 95% CI: 1.06–1.65) and gastrointestinal infections (OR = 1.37, 95% CI: 1.01–1.86), but ear infection showed similar results in the cohort study (OR = 1.13, 95% CI: 1.04–1.22). Conclusion: Current evidence suggests that infection during pregnancy, early upper respiratory infection, gastrointestinal infections and ear infection within 2 years of age would increase the risk of AR in children. Therefore, the prevention of infection during pregnancy and in infancy and young children needs to be emphasized.

TRNA-derived small RNAs (tsRNAs) are a class of non-coding RNAs(ncRNAs) generated from precursor or mature tRNAs under stress conditions, such as starvation, hypoxia, or oxidative stress. They are broadly classified into a growing class of small RNAs, known as tRNA-derived RNA (tDR), tRNA-derived small RNAs or tRNA-derived fragments and tRNA-derived stress-induced RNAs (tiRNAs) based on their cleavage sites. Recent advances in high-throughput sequencing have revealed their critical roles in the reproductive system, particularly in spermatogenesis, sperm maturation, and male infertility. In females, tsRNAs are implicated in oocyte development and embryo implantation. Dysregulation of tsRNAs has also been linked to reproductive diseases, including polycystic ovary syndrome (PCOS) and endometriosis in women, and oligospermia or azoospermia in men. Mechanistically, tsRNAs regulate gene expression, mRNA stability, and translation, influencing key pathways in reproductive health and disease. Their potential as biomarkers and therapeutic targets for reproductive disorders is increasingly recognized, though further research is needed to fully elucidate their roles and clinical applications.