RESUMEN
Background: This study aimed to investigate putative causal effects between constipation and stroke using bidirectional Mendelian randomization (MR) analysis. Methods: Based on the cross-sectional study, logistic regression models were developed to assess the association between constipation and stroke prevalence. Subsequently, genome-wide association studies statistics were employed to perform MR analysis between constipation and stroke, as well as its subtypes. The inverse variance weighting (IVW) method was the primary method, complemented by four additional methods, namely weighted median, weighted mode, simple mode, and MR-Egger regression. Cochran's Q test, MR-Egger intercept test, MR Pleiotropy RESidual Sum and Outlier, and MR Steiger test were performed to assess heterogeneity and pleiotropy effects. Results: Constipation was associated with a greater risk of stroke even after adjusting for all covariates in logistic regression [odds ratio (OR) = 1.46, 95% confidence interval (CI) = 1.01-2.09, p = 0.042]. IVW MR analysis revealed that constipation affected large artery atherosclerosis (LAS; IVW OR = 1.5, 95% CI = 1.07-2.104, p = 0.019). No significant or suggestive association was observed with the risk of stroke or its various subtypes in MR analysis. Meanwhile, reverse MR analysis revealed no significant causal relationship between stroke or other stroke subtypes and constipation. The results of sensitivity analyses revealed no significant horizontal pleiotropy affecting causal estimates. Conclusion: While cross-sectional studies have established that constipation increases the risk of stroke, this two-sample bidirectional MR analysis revealed a positive correlation between constipation and LAS. However, no such correlation was observed between constipation and stroke, including its various subtypes.
RESUMEN
Hybrid breeding is the most important means of selecting pear (Pyrus) varieties, but a long juvenile period severely restricts the selection of new varieties. In this study, we used 'Yuluxiang' × 'Akituki' 4-year-old seedling trees to study the effects of plant growth regulators, ring stripping, and ring cutting on the promotion of phase change and flowering to assist in shortening the breeding cycle. A single application of 100 mg/kg 6-BA + 1000 mg/kg PP333 was most effective in promoting phase change and flowering. This treatment effectively inhibited the growth and thickening of annual shoots, significantly increased soluble sugar and protein contents in buds, increased the ABA content by 45.41%, decreased the IAA content by 7.35%, increased the expression of the flower-promoting genes FT and LFY by 2273.41% and 1153.71%, respectively, and decreased the expression of the flower-suppressing gene TFL1 by 74.92%. The flowering plant rate increased by 23.34% compared to the control. Both ring stripping and ring cutting were effective in promoting phase change and flowering, significantly increasing the flowering rate, inflorescence number, and the number of flowering plants. For improving the flowering rate, the ring-stripping treatment had the strongest effect and effectively inhibited the growth and thickening of annual shoots, while also significantly increasing the soluble sugar and protein contents in buds, reducing the contents of IAA and GA3 by 8.73% and 50.12%, respectively, increasing the expression of FT and LFY by 80.01% and 821.14%, respectively, and reducing the expression of the flower-suppressing gene TFL1 by 59.22%. In conclusion, ring stripping, ring cutting, and spraying of 100 mg/kg 6-BA + 1000 mg/kg PP333 were effective in promoting phase change and early flowering in seedling trees.
