ObjectiveTo explore the effects of hypoxia on the migration ability of human oligodendrocyte precursor cells （hOPCs） and its regulatory mechanisms. MethodsBased on the variations in oxygen concentration within the culture system， three experimental groups were set up： the 21%O₂ group （normoxic control group）， the 5%O₂ group， and the 2%O₂ group. The migration ability of hOPCs under normoxia （21%O₂）， 5%O₂， and 2%O₂ conditions was detected through the Transwell migration assay. RT-qPCR， transcriptome sequencing， and flow cytometry were used to detect the expression changes of genes and proteins such as hypoxia-inducible factor 1 alpha （HIF-1α） and chemokine （C-X-C Motif） receptor 4 （CXCR4）. Bioinformatics analysis was combined to analyze the KEGG pathways related to migration， so as to explore the effects of different oxygen concentrations on the migration ability of hOPCs and their possible mechanisms. ResultsHypoxia treatments at concentrations of 5%O₂ and 2%O₂ could both promote the in vitro migration of hOPCs， and the promoting effect of migration was more significant at the 2%O₂ concentration （P<0.001）. After hypoxia treatment， the mRNA expression levels of HIF-1α， CXCR4， etc. in hOPCs significantly increased （P<0.001）. Compared with the 5%O₂ concentration， the expression of CXCR4 in cells was higher at the 2%O₂ concentration （P<0.000 1）. Flow cytometry analysis detection showed that the expression of CXCR4 increased significantly after hypoxia treatment （P<0.01）， and with the decrease of oxygen concentration， its expression level further increased （P<0.000 1）. Ordinary transcriptome sequencing analysis indicated that hypoxia treatment could activate the PI3K-Akt signaling pathway and the Axon guidance pathway. ConclusionHypoxia treatment can enhance the in vitro migration ability of hOPCs， and this effect is negatively correlated with the oxygen concentration. Its mechanism may be related to the up-regulation of the expression of genes such as HIF-1α and CXCR4， and the activation of the migration related signaling pathway including PI3K-Akt signaling pathway and axon guidance pathway.

ObjectiveTo investigate the mechanism by which Notoginsenoside R1 （NGR1） ameliorates hypoxia/reoxygenation （H/R）-induced injury in AC16 human cardiomyocyte cell lines through the regulation of mitophagy. MethodsCommon genes linked to hypoxia/reoxygenation injury and mitophagy were identified by intersecting data from GeneCards and MitoCarta databases. AC16 cell viability was assessed via CCK-8 assay under varying NGR1 concentrations （0， 6.25， 12.5， 25， 50， 100， 200， 300， 400， 500 μmol/L）. AC16 cells were divided into the following groups： control group （Control）， model group （H/R）， and treatment groups （H/R + NGR1 at 100， 200 and 300 μmol/L）. Mitochondrial membrane potential （ΔΨm） was measured using 5，5'，6，6'-tetrachloro-1，1'，3，3'-tetraethylbenzimidazolylcarbocyanine iodide （JC-1） staining. Transcriptional levels of mitophagy-related genes （Parkin， Pink1， P62） were quantified by reverse transcription-quantitative PCR （RT-qPCR）. Protein expression of mitophagy-related markers （Parkin， Pink1， P62， and LC3BⅡ） was evaluated via Western blot analysis. Mitochondrial ultrastructure was visualized by transmission electron microscopy （TEM）. ResultsCompared to the control group， cell viability in the H/R group significantly decreased （P<0.01）. Treatment with NGR1 at concentrations above 100 μmol/L significantly enhanced the cell viability of AC16 cells compared to the H/R group （P<0.01）. H/R induced a significant decrease in mitochondrial membrane potential （P<0.01）， which was restored by NGR1 treatment （P<0.01）. The mRNA levels of Parkin， Pink1， and P62 in the H/R group were upregulated compared to the control group （P<0.05）， while NGR1 intervention downregulated their expression （P<0.05）. Protein expression levels of Parkin， Pink1， and LC3BⅡ in the H/R group significantly increased， while P62 expression decreased compared to the control group （P<0.01）. In contrast， different doses of NGR1 treatment significantly reduced the expression of Parkin， Pink1， and LC3BⅡ while increasing P62 expression （P<0.05）. TEM revealed that the mitochondrial structure in the H/R group was severely disrupted， with fragmented and disorganized cristae， which was alleviated by NGR1. ConclusionNGR1 ameliorates H/R-induced AC16 cell injury， and its mechanism may be associated with modulating the Pink1/Parkin pathway to suppress excessive mitophagy.

Objective To investigate the independent risk factors affecting the prognosis of chronic active antibody-mediated rejection (caAMR) after kidney transplantation. Methods A retrospective analysis was conducted on 61 patients who underwent renal biopsy and were diagnosed with caAMR. The patients were divided into caAMR group (n=41) and caAMR+TCMR group (n=20) based on the presence or absence of concurrent acute T cell-mediated rejection (TCMR). The patients were followed up for 3 years. The value of 24-hour urinary protein and estimated glomerular filtration rate (eGFR) at the time of biopsy in predicting graft loss was assessed using receiver operating characteristic (ROC) curves. The independent risk factors affecting caAMR prognosis were analyzed using the LASSO-Cox regression model. The correlation between grouping, outcomes, and Banff scores was compared using Spearman rank correlation matrix analysis. Kaplan-Meier analysis was used to evaluate the renal allograft survival rates of each subgroup. Results The 3-year renal allograft survival rates for the caAMR group and the caAMR+TCMR group were 83% and 79%, respectively. The area under the ROC curve (AUC) for predicting 3-year renal allograft loss was 0.83 ［95% confidence interval (CI) 0.70-0.97］ for eGFR and 0.78 (95% CI 0.61-0.96) for 24-hour urinary protein at the time of biopsy. LASSO-Cox regression analysis and Kaplan-Meier analysis showed that eGFR≤25.23 mL/(min·1.73 m²) and the presence of donor-specific antibody (DSA) against human leukocyte antigen (HLA) class I might be independent risk factors affecting renal allograft prognosis, with hazard ratios of 7.67 (95% CI 2.18-27.02) and 5.13 (95% CI 1.33-19.80), respectively. A strong correlation was found between the Banff chronic lesion indicators of renal interstitial fibrosis and tubular atrophy (P<0.05). Conclusions The presence of HLA class I DSA and eGFR≤25.23 mL/(min·1.73 m²) at the time of biopsy may be independent risk factors affecting the prognosis of caAMR.

Objective: To investigate the association between plant-based dietary patterns and gestational weight gain (GWG) among pregnant women with gestational diabetes mellitus (GDM), so as to provide the evidence for guiding the reasonable diet during pregnancy. Methods: GDM pregnant women who participated in the WeBirth project in Hangzhou Obstetrics and Gynecology Hospital were selected. Maternal age and pre-pregnancy body mass index (BMI) were collected. The Chinese version of Pregnancy Physical Activity questionnaire was used to assess the daily activity equivalent. The food frequency questionnaire was used to collect the frequency and amount of food intake in the last month before enrollment. The overall plant-based diet index (PDI), healthy plant-based diet index (HPDI), and unhealthy plant-based diet index (UPDI) were constructed based on food intake and grouped by quartiles. Multiple linear regression models were used to analyze the association between plant-based dietary patterns and GWG. Results: A total of 1 943 pregnant women with GDM, with a median age of 30.91 (interquartile range, 4.92) years. The median BMI of pre-pregnancy was 21.51 (interquartile range, 4.06) kg/m2. The medians of PDI, HPDI and UPDI were 32.42 (interquartile range, 4.60), 32.48 (interquartile range, 4.41) and 32.40 (interquartile range, 5.36), respectively. The median of GWG was 11.30 (interquartile range, 4.52) kg. Multiple linear regression analysis showed that PDI (Q3 group, β=0.674, 95%CI: 0.064-1.285; Q4 group, β=0.702, 95%CI: 0.098-1.306), UPDI (Q3 group, β=1.332, 95%CI: 0.771-1.894; Q4 group, β=1.115, 95%CI: 0.550-1.681) were positively associated with GWG after adjusting for age, pre-pregnancy BMI, daily activity equivalent and daily energy intake. No significant association was found between HPDI and GWG (all P>0.05). Conclusion UPDI was associated with a higher risk of GWG in pregnant women with GDM.

ObjectiveThe U6 promoter is an essential element for driving sgRNA expression in the clustered regularly interspaced short palindromic repeat sequences/CRISPR-associated protein 9（CRISPR/Cas9）gene editing system in dicotyledonous plants. Endogenous U6 promoters typically exhibit higher transcriptional activity， which can significantly improve gene editing efficiency. This study aims to identify endogenous U6 promoters in Artemisia annua to optimize its CRISPR/Cas9 gene editing system， which holds significant importance for its molecular breeding. MethodsOn the basis of the highly conserved U6 snRNA sequences in Arabidopsis thaliana， endogenous U6 promoters were screened in the A. annua genome. Expression vectors were constructed with candidate AaU6 promoter driving the firefly luciferase （LUC） reporter gene， and then transiently transformed into Nicotiana benthamiana. Transcriptional activities of the promoters were measured and compared by in vivo imaging and the Dual Luciferase Reporter assay. ResultsEight endogenous U6 promoters were successfully cloned from A. annua. Sequences alignment revealed that all these promoters contained the two conserved cis-acting elements， upstream sequence element （USE） and TATA-box， which affected their transcriptional activity. Dual-luciferase activity assays indicated that the transcriptional activities of AaU6-3， AaU6-1， and AaU6-5 were significantly higher than that of the Arabidopsis AtU6-26 promoter， with AaU6-3 exhibiting the highest activity. ConclusionThis study identified three endogenous AaU6 promoters with high transcriptional activity in A. annua， providing key functional elements for establishing an efficient gene editing system in A. annua. These findings will contribute to advancing precision molecular breeding and high-quality germplasm innovation in A. annua.