Limbal niche cells (LNCs) in the limbal niche, a type of mesenchymal stem cells closely associated with limbal epithelial stem/progenitor cells (LESCs), heterogeneously express both mesenchymal and putative embryonic stem cell markers and play a critical role in regulating the quiescence, self-renewal, and differentiation of LESCs.Previous studies have shown that LNCs can be isolated by collagenase, dispase, dispase-collagenase and explant culture.Transwell and 3D Matrigel coculture are widely used in ex vivo studies of LNCs and LESCs, and the interactive mechanism may include SDF-1/CXCR4, Notch, BMP, Wnt, Sonic Hedgehog, and KIT/AKT signaling pathways, and various cytokines such as nerve growth factor, keratinocyte growth factor, and insulin-like growth factor.LNCs have become a hot topic in corneal epithelial tissue engineering, ocular surface reconstruction, and corneal regeneration.This review provides an overview of the research background, isolation and culture methods, interaction mechanism of LNCs with LESCs, and its application prospects.

Objective:To investigate the effect of astragaloside IV (AS-IV) regulating the signal axis of stromal cell-derived factor-1α (SDF-1α)/CXC chemokine receptor 4 (CXCR4) on the mobilization of bone marrow endothelial progenitor cells (EPCs) to peripheral blood in diabetes skin ulcer (DSU) rats.Methods:Twenty four SPF grade male Sprague Dawley (SD) rats were selected to make the model of type 2 diabetes rats by intraperitoneal injection of 30 mg/kg 1% (plastid ratio) streptozotocin, and then round full-thickness skin with a diameter of 2 cm was cut on both sides of the waist and back to make the skin ulcer model of diabetes rats. After that, they were randomly divided into AS-IV group (50 mg/kg AS-IV), blocker group (50 mg/kg AS-IV+ 5 mg/kg AMD3100) and model group. At the same time, a blank group ( n=8) was set up, The drug was administered via intraperitoneal injection, and the model group and blank group were treated with 0.9% NaCl of equal volume. On the 10th day, peripheral blood, femoral bone marrow, and wound neovascularization tissues of rats were collected. The number of EPCs in peripheral blood of each group of rats was measured by flow cytometry, and the protein expression of SDF-1α and CXCR4 in peripheral blood, femoral bone marrow, and wound neovascularization tissues of rats was detected by enzyme-linked immunosorbent assay (ELISA); At the same time, the wound healing rates of each group were tested. Results:On the 10th and 21st day after modeling, the wound healing rate of each group of rats was compared. The blank group healed the fastest, while the model group healed the slowest. The AS-IV group had better healing than the model group and the blocker group, and the difference was statistically significant (all P<0.05). On the 10th day after modeling, the positive rates of peripheral blood EPCs in the white group, AS-IV group, and blocker group were significantly higher than those in the model group (all P<0.05), while the positive rates of peripheral blood EPCs in the blocker group were significantly lower than those in the AS-IV group (all P<0.05). On the 10th day after modeling, the protein expression of SDF-1α and CXCR4 in the wound, serum, and bone marrow of the model group was the lowest, while the protein expression in the blank group was the highest (all P<0.05). The protein expression of SDF-1α and CXCR4 in the wound, serum, bone marrow of the AS-IV group was significantly higher than that of the blocker group and model group, and the difference was statistically significant (all P<0.05). Conclusions:Astragaloside IV can promote the mobilization and migration of endothelial progenitor cells from bone marrow to peripheral blood in diabetes ulcer rats by regulating SDF-1α/CXCR4 signal axis, and can participate in angiogenesis of diabetes ulcer wounds as seed cells to promote the healing of diabetes skin ulcers.

Objective:Cerebral ischemia reperfusion injury(CIRI)can cause damage to distant organs,such as the gastrointestinal tract,through the gut-brain axis.Melatonin is known to play a neuroprotective role by activating specific receptor pathways.However,the changes of melatonin receptors in the gastrointestinal tract after brain injury and their relationship with intestinal injury are still unclear.Methods:Twenty-four male Sprague-Dawley rats were randomly di-vided into the Sham group and CIRI group.The CIRI model was prepared by Zea-Longa method.The jejunum,ileum,and colon tissues of the rats were collected 2 h after ischemia and 24 h after reperfusion.The damage of intestinal and brain tissues was observed by using 2,3,5-triphenyl tetrazolium chloride(TTC)and HE staining.The positive expres-sion of zonula occludens-1(ZO-1)and Claudin5 was observed by immunofluorescence staining.The melatonin receptor 1(MT1)and melatonin receptor 2(MT2)expression was detected by reverse transcription-quantitative polymerase chain reaction(RT-qPCR),immunofluorescence staining and Western Blot.The correlation between the melatonin receptors and intestinal tight junction proteins was analyzed by general linear regression.Results:TTC staining showed that the infarct size of rats in the CIRI group was significantly higher than that in the Sham group.HE staining showed that intestinal villi was broken and shortened,and goblet cells were reduced in the CIRI group.The results of immuno-fluorescence staining revealed that the positive expression of ZO-1 and Claudin5 in the intestinal tissues of rats in the CIRI group was significantly lower than that in the Sham group(P＜0.05).Compared with the Sham group,the RT-qPCR revealed a significantly lower expression of MT1 and MT2 mRNA in the CIRI group(P＜0.05),and the decrease in colon tissue was the most obvious.The results of immunofluorescence staining and WB also showed that the expression of MTl and MT2 in the CIRI group was significantly lower than that in the Sham group(P＜0.05).A gen-eral linear regression analysis revealed the difference in mean fluorescence intensities of MT1+and MT2+between the Sham group and the CIRI group were positively correlated with the difference of ZO-1+and Claudin5+between the two groups.Conclusion:After CIRI,the expression of both MT1 and MT2 receptors in various intestinal segments was de-creased,and the decrease in colon tissue was the most significant.It is suggested that the poor recovery of stroke may be related to the decrease of melatonin receptor.

Objective·To investigate the predictive value of the Clinical Frailty Scale(CFS)in the long term outcomes in acute myocardial infarction(AMI)patients who completed in-hospital cardiac rehabilitation(CR).Methods·A total of 501 AMI patients treated in the Cardiology Center of Shanghai Sixth People's Hospital,Shanghai Jiao Tong University of Medicine from May 2020 to May 2022 were prospectively enrolled,with their baseline clinical data collected.The patients completed graded in-hospital CR and were assessed by CFS based on their completion of CR before discharge.Patients were then categorized into three groups(norm group,vulnerable group and frail group)according to their CFS level.The difference in 1-year major cardiovascular event(all-cause death and re-hospitalization for heart failure)rates among the three groups was investigated.Logistic regression analysis was performed to explore the effective risk factors relevant to the outcomes,and receiver operator characteristic(ROC)curves were generated to analyze the prognostic value.Finally,an optimal prediction model was developed.Results·The CFS level in AMI patients who completed CR was positively correlated with age and peak pro-B-type natriuretic peptide(peak proBNP),and inversely correlated with gender difference(P<0.05).Accompanied with the elevated CFS level,the incidence of both outcomes increased,and there were significant differences in all-cause death(2.6%,5.6%and 15.2%,P=0.002),and while no significant differences in re-hospitalization for heart failure among the three groups(19.6%,22.2%and 24.2%).All-cause death of the frail group was significantly higher than that of the norm group(P=0.004),while there was no significant difference between the vulnerable group and the norm group.CFS could sensitively predict the 1-year all-cause death in AMI patients(β=1.89,OR=6.61,P=0.001),and the risk model combined with CFS had the best predictive effect(AUC=0.845,P=0.000).Conclusion·Assessment by CFS in AMI patients who completed in-hospital CR contributes to identifying AMI patients with high risk of all-cause death in 1 year.

Objective:To explore whether acute pancreatitis, chronic pancreatitis and alcoholic pancreatitis are related to the incidence of pancreatic cancer in Mendelian randomization study.Methods:Using data from a genome-wide association study (GWAS) of European ancestry, the pancreatic cancer data in the UK population is obtained from the GWAS. Acute, chronic, and alcoholic pancreatitis data in the Finnish population is obtained from the Finnish database version R10. The correlation between acute, chro-nic pancreatitis, alcoholic pancreatitis and pancreatic cancer was analyzed by two-sample Mendelian randomization through five Mendelian analysis methods mainly based on inverse variance weighting. Q heterogeneity test, pleiotropy test and reverse test were carried out to ensure the robustness of the results.Results:Chronic pancreatitis was positively associated with pancreatic cancer ( OR=1.332, 95% CI: 1.044-1.698, P=0.021). The results of Q heterogeneity test, pleiotropy test and reverse Mendelian randomization showed that the conclusions were reliability, all P>0.05. While acute pancreatitis ( P=0.953), acute alcoholic pancreatitis ( P=0.862) and chronic alcoholic pancreatitis ( P=0.682) were not significantly associated with pancreatic cancer. Conclusion:This study further confirmed the strong correlation between chronic pancreatitis and pancreatic cancer at the genetic level.

Objective To explore the influencing factors of ecological momentary assessment(EMA)in the implementation of home rehabilitation exercise for middle-aged stroke patients,and to provide a basis for decision-making and practice of precision rehabilitation nursing for stroke.Methods This descriptive qualitative research utilized purposive sampling method to select 8 medical staff,4 information technicians,8 middle-aged stroke patients,and 5 caregivers from a tertiary A general hospital in Wuhan from January 2 to March 10,2024 as the research subjects.Semi-structured interview was conducted based on the framework of diffusion of innovations theory.The data were analyzed using directed content analysis.Results 5 themes and 10 sub-themes were extracted,including relative advantage factors(conducive to precise and dynamic evaluation of patient rehabilitation behavior and symptom trajectory by medical staff;enhancing patient self-management awareness,effectively reducing care burden),compatibility factors(new methods conflict with existing values;new methods are in line with clinical work practice),complexity factors(evaluation frequency affects the accuracy of rehabilitation tracking;limited limb function and social support increase user burden),experimental factors(pilot and real-time feedback improve user experience;experience summary and promotion,the strengthening of practical verification orientation),and observable factors(successful cases of mobile health help popularize new methods;visualization of new methods to enrich mobile health practice).Conclusion There are certain promoting and hindering factors in the implementation of EMA in the field of home rehabilitation exercise for middle-aged stroke patients.In the future,it is necessary to explore the potential of EMA in the field of precision rehabilitation and ensure its compatibility with clinical practice.

Objective To identify M1 macrophage-related genes in rejection after kidney transplantation and construct a risk prediction model for renal allograft survival. Methods GSE36059 and GSE21374 datasets after kidney transplantation were downloaded from Gene Expression Omnibus (GEO) database. GSE36059 dataset included the samples from the recipients with rejection and stable allografts. Using this dataset, weighted gene co-expression network analysis (WGCNA) and differential analysis were conducted to screen the M1 macrophage-related differentially expressed gene (M1-DEG). Then, GSE21374 dataset (including the follow-up data of graft loss) was divided into the training set and validation set according to a ratio of 7∶3. In the training set, a multivariate Cox's model was constructed using the variables screened by least absolute shrinkage and selection operator (LASSO), and the ability of this model to predict allograft survival was evaluated. CIBERSORT was employed to analyze the differences of infiltrated immune cells between the high-risk group and low-risk group, and the distribution of human leukocyte antigen (HLA)-related genes was analyzed between two groups. Gene set enrichment analysis (GSEA) was used to further clarify the biological process and pathway enrichment in the high-risk group. Finally, the database was employed to predict the microRNA (miRNA) interacting with the prognostic genes. Results In the GSE36059 dataset, 14 M1-DEG were screened. In the GSE21374 dataset, Toll-like receptor 8 (TLR8), Fc gamma receptor 1B (FCGR1B), BCL2 related protein A1 (BCL2A1), cathepsin S (CTSS), guanylate binding protein 2(GBP2) and caspase recruitment domain family member 16 (CARD16) were screened by LASSO-Cox regression analysis, and a multivariate Cox's model was constructed based on these 6 M1-DEG. The area under curve (AUC) of receiver operating characteristic of this model for predicting the 1- and 3-year graft survival was 0.918 and 0.877 in the training set, and 0.765 and 0.736 in the validation set, respectively. Immune cell infiltration analysis showed that the infiltration of rest and activated CD4⁺ memory T cells, γδT cells and M1 macrophages were increased in the high-risk group (all P < 0.05). The expression level of HLA I gene was up-regulated in the high-risk group. GSEA analysis suggested that immune response and graft rejection were enriched in the high-risk group. CTSS interacted with 8 miRNA, BCL2A1 and GBP2 interacted with 3 miRNA, and FCGR1B interacted with 1 miRNA. Conclusions The prognostic risk model based on 6 M1-DEG has high performance in predicting graft survival, which may provide evidence for early interventions for high-risk recipients.

【Objective】 To observe the role of liver/bone/kidney alkaline phosphatase gene (ALPL) in liver regeneration following 70% hepatectomy (partial hepatectomy, PH). 【Methods】 A knock-out mouse model (ALPL^+/-) was established, and a 70% hepatectomy was performed. Changes in liver weight and liver function were measured at PH 1 day, PH 3 day, and PH 7 day (PH1d、PH3d、PH7d) after surgery. In addition, cell proliferation, hepatocyte growth factor (HGF), and vascular endothelial growth factor (VEGF) were performed by Western blotting, immunofluorescence staining, and enzyme linked immunosorbent assay. 【Results】 ALPL knockout mice at PH7d exhibited a lower ratio of liver/total body weight than normal control mice. An analysis of liver function showed no significant difference between the ALPL knockout group and the WT (ALPL^+/+) group when the ALPL gene was deleted. While Ki67 staining and PCNA analysis indicated that liver cell proliferation was decreased in ALPL^+/- mice at PH1d and increased at PH7d compared to that in ALPL^+/+group. Additionally, knockouts of ALPL decreased serum and liver HGF and VEGF levels at PH1d compared to WT controls, but increased at PH7d. 【Conclusion】 The knockout of ALPL leads to a delayed liver regeneration following hepatectomy, which provides theoretical support for exploring the mechanisms underlying liver regeneration after hepatectomy.

Objective:To observe the effects of problem-based learning (PBL) and case-based learning (CBL) combined with self-media platform in clinical probation teaching of gastroenterology.Methods:From July 2019 to June 2020, 60 students in the Department of Gastroenterology of the Army Characteristic Medical Center of PLA were assigned to the traditional teaching group (control group, n=30) and the PBL and CBL combined with the self-media platform teaching group (experimental group, n=30). After the teaching, theoretical examination, practical assessment, and questionnaires were used to evaluate the effects of the two teaching methods. SPSS 23.0 was used to perform the t-test. Results:The comprehensive scores of students in the experimental group, including theoretical examination score (86.60±1.17) and practical assessment score (86.40±0.83), were significantly higher than those in the control group [(81.70±0.98), (82.00±1.18), P<0.001]. The questionnaire survey showed that the experimental group was superior to the traditional teaching group in terms of self-study and data access ability, students' self-confidence, and satisfaction with teaching ( P<0.001). Conclusion:PBL and CBL combined with self-media platform uses actual medical records to guide students to discuss, analyze, and summarize clinical issues. Combined with flexible learning on the self-media platform, this method breaks through the limitations of traditional teaching models and improves teaching quality and learning satisfaction. Therefore, this method can be promoted in clinical probation teaching of gastroenterology.

Objective To explore left ventricular longitudinal systolic function changes during perioperative period of coronary artery bypass graft(CABG).Methods Totally 41 patients with confirmed coronary artery disease(CAD)who underwent CABG were prospectively enrolled.The preoperative left ventricular global longitudinal strain(GLS),as well as GLS on the day of CABG,on the 3rd and 7th day postoperation were measured.According to preoperative left ventricular GLS,the patients were divided into 3 groups,i.e.normal group(group A,GLS≤-18.1％,n=6),mildly decreased group(group B,-18.1％＜GLS≤-14.0％,n=22)and severely decreased group(group C,GLS＞-14.0％,n=13).Repeated measures analysis of variance,generalized estimating equation and multiple comparisons were used to analyze left ventricular systolic function in different perioperative time points.Results No significant difference of GLS was found among different time points during perioperative period of CABG in group A and C(all adjusted P＞0.05).In group B,GLS on postoperative days were lower than that before CABG(all adjusted P＜0.001),and the lowest value was observed on the day of CABG postoperatively,while no significant difference of GLS was found between the 3rd and 7th day postoperation(adjusted P=1.00).Compared with those before CABG,the longitudinal strain(LS)of basal segment on the day of CABG postoperatively and 3rd day postoperation,of middle segment and apical segment at all postoperative time points were lower(all adjusted P＜0.05),while of the apical segment on the day of CABG postoperatively decreased most obviously.No significant difference of LS of each ventricular segment was found between the 3rd nor the 7th day postoperation(all adjusted P＞0.05).Conclusion GLS decreased significantly on the day of CABG postoperatively but partially recovered within the following week in CAD patients with mildly decreased preoperative GLS.CABG had the most pronounced effect on LS of apical segment in left ventricle.