AIM: To detect the distribution and expression of vascular endothelial growth factor(VEGF)in radiation retinopathy(RR)through fluorescence targeted imaging.METHODS:Covalent binding of fluorescein FITC with VEGF antibody ranibizumab to prepare targeted fluorescent imaging probe ranibizumab-FITC. SD rats were randomly divided into three groups based on the principle of weight balance: a normal control group(Con group), a low-dose radiation group(10 Gy group), and a high-dose radiation group(30 Gy group). Medical linear accelerators and lead blocks were used to locally irradiate the rat eyeballs for modeling. Western blot and qRT-PCR were used to detect the expression levels of VEGF-A in each group and to screen for appropriate modeling dose. The inverted fluorescence microscope and the confocal microscope were used to observe the distribution of VEGF and imaging probes in the retinas of control and RR model group rats, and to verify the effectiveness of targeted probes.RESULTS:The expression level of VEGF-A in the retina of rats in the high-dose radiation group(30 Gy group)was higher than that in the normal control group(Con group). In early RR, VEGF expression was observed to be associated with microaneurysms and abnormal microvessels in the retina. VEGF accumulation was observed at the site of capillary wall damage. When retinal capillary endothelial damage occurred, targeted probes gathered on the outer surface of the vessel wall.CONCLUSION:The expression level of VEGF in the retina of RR model rats is elevated, and fluorescent targeted molecular imaging probes can detect the spatial distribution of VEGF at the microvascular lesions in the retina of RR rats.

Disruption of the intestinal mucosal barrier caused by gut dysbiosis and metabolic imbalance is the underlying pathology of inflammatory bowel disease (IBD). Traditional Chinese medicine Wuji Wan (WJW) is commonly used to treat digestive system disorders and showed therapeutic potential for IBD. In this interdisciplinary study, we aim to investigate the pharmacological effects of WJW against experimental colitis by combining functional metabolomics and gut-microbiota sequencing techniques. Treatment with WJW altered the profile of the intestinal microbiota and notably increased the abundance of Lactobacillus, thereby facilitating the conversion of tryptophan into indole-3-acetic acid (IAA) and indoleacrylic acid (IA). These indole derivatives activated the aryl hydrocarbon receptor (AhR) pathway, which reduced colonic inflammation and restored the expression of intestinal barrier proteins. Interestingly, the beneficial effects of WJW on gut barrier function improvement and tryptophan metabolism were disappeared in the absence of gut microbiota. Finally, pre-treatment with the AhR antagonist CH-223191 confirmed the essential role of IAA-mediated AhR activation in the therapeutic effects of WJW. Overall, WJW enhanced intestinal barrier function and reduced colonic inflammation in a murine colitis model by modulating Lactobacillus-IAA-AhR signaling pathway. This study provides novel insights into colitis pathogenesis and presents an effective therapeutic and preventive approach against IBD.

Objective To investigate the incidence of functional bowel disease(FBD)and its relationship with depression,anxiety and sleep in navy submarine forces.Methods A questionnaire survey on the incidence of FBD was conducted on 364 naval soldiers who were enrolled according to Rome Ⅳ classification and diagnostic criteria.The risk factors of FBD were analyzed.The incidence of specific diseases of FBD was compared among soldiers with different jobs.The depression,anxiety,and sleep quality were investigated in FBD patients.Results In the 364 participants,132(36.3%)were diagnosed with FBD according to Roman Ⅳcriteria.Military rank and marital status might be risk factors for FBD.There was no significant difference in the overall incidence of FBD among the participants with various jobs(P>0.05).The incidence of functional constipation in the submariners was significantly higher than that in the land soldiers,while the incidence of functional diarrhea in the land soldiers was higher than that in the submariners(all P<0.05).The incidences of depression,anxiety and sleep disorder in the participants with FBD were higher than those in the participants without FBD.Conclusion There is a high incidence of FBD in submariners,which may be related to their psychological states.

Empathy is a cornerstone in cultivating medical ethics.This article delves into the profound significance of empathy and underscores the importance of promoting it among medical students and practitioners.It also details methods for strengthening empathy and capacity building concerned in students through oral medicine instruction,with the goal of nurturing oral healthcare professionals who provide compassionate care.

Objective To evaluate the application of modified chairside case-based learning(CBL)in the teaching of dental residents in the prosthodontic clinic.Methods Dental residents in Peking Union Medical College Hospital from September 2022 to September 2024 were enrolled.Traditional CBL was conducted in control group.Modified chairside CBL was conducted in test group.The scores of department rotation examination and questionnaire results were analyzed with t-test statistical analysis.Results The score of"patient reception"in test group was significantly higher than control group(P＜0.05).24 valid questionnaires were collected in two groups each.The rate of approval in test group was significantly higher than control group in the following items of questionnaire,including"reduce learning pressure or burden""improve the capacity of doctor-patient communication""improve the capacity of literature review""improve the capacity of group cooperation"(P＜0.05).Conclusions Modified chairside CBL has showed good teaching effects in improving the capacity of patient reception,doctor-patient communication,literature review,group cooperation,and meanwhile reduced learning pressure or burden.

Objective To explore the need and evaluate the effectiveness for head-simulator in the teaching of sto-matology within the eight-year program of clinical medicine.Methods Questionnaire survey was conducted among the students from 2017 cohort of the eight-year program of clinical medicine at Peking Union Medical College.The survey results were statistically analyzed and described.Results Totally 87.9％of the students believed that incor-porating head-simulator into the clinical practice course of stomatology were necessary,and 93.9％expressed will-ingness to join the training.Most students preferred to practice peri-odontal scaling and cavity preparation for caries during the simulated training sessions.The majority of students considered two or four class hours of simulated head teaching to be reasonable.The pilot head simulation training was successfully implemented;75.0％of the students acknowledged clear teaching and convincible demonstrations.All the trainees agreed that the head simulation course helped them better understand stomatology knowledge,stimulated their interest in learning and expressed a desire for increased head simulation sessions during clinical practice course of stomatology.Additionally,87.5％of the students preferred head simulation training course to be applied in classic clinical clerkships.Conclusions There is strong demand among students of eight-year program of clinical medicine for incorporating head-simulator into the education of stomatology.The pilot simulation training received positive evaluations.Further exploration is needed to optimize specific scheduling and content arrangement.

Objective:To discuss the effect of erythritol on glucose and lipid metabolism in the body,and to clarify the mechanism of erythritol affecting liver metabolism based on metabonomics.Methods:The male ICR mice were randomly divided into normal group,sucrose group(2％sucrose),low dose of erythritol(1％erythritol)group,medium dose of erythritol(2％erythritol)group,and high dose of erythritol(4％erythritol)group,with 10 mice in each group.The corresponding concentrations of sucrose and erythritol solutions were prepared and placed in water bottles,and the mice were allowed to drink and eat freely for 12 consecutive weeks;the body mass,food intakes,and water intakes of the mice in various groups were measured.Commercial kits were used to detect the serum triglyceride(TG),total cholesterol(TC),and blood glucose levels of the mice in various groups;the liver indexes of the mice were calculated.Ultra performance liquid chromatography-orbitrap exactive mass spectrometry(UPLC-OE-MS)non-targeted metabonomics was used to detect the liver metabolites of the mice normal group and high dose of erythritol group;bioinformatics analysis was used to screen the differential liver metabolites between the two groups with variable importance in projection(VIP)＞1 and adjusted P＜0.05;Kyoto Encyclopedia of Genes and Genomes(KEGG)signaling pathway enrichment analysis were performed to investigate the functional roles of the differential liver metabolites.Results:Compared with normal group,there were no significant differences in the body mass,food intake,liver index,and blood lipid levels of the mice in various groups(P＞0.05);compared with normal group,the blood glucose level of the mice in high dose of erythritol group was significantly increased(P＜0.01).The metabonomics analysis of the liver tissues of the mice in two groups identified 1 144 metabolites,mainly including lipids and lipid-like molecules(17.39％),organic acids and derivatives(10.87％),organic heterocyclic compounds(5.80％),and organic oxygen compounds(5.07％).Compared with normal group,there were 138 differential liver metabolites in the mice in high dose of erythritol group,among which 112 metabolites were up-regulated and 26 metabolites were down-regulated.The KEGG signal pathway enrichment analysis results showed that the differential metabolites were mainly enriched in metabolism,steroid hormone biosynthesis,cortisol synthesis and metabolism,and Cushing's syndrome pathways;the further topological analysis of the metabolic pathways results showed that the differential metabolites were mainly involved in sphingolipid metabolism,tricarboxylic acid cycle,riboflavin metabolism,steroid hormone biosynthesis,and purine metabolism signal pathways.Conclusion:Long-term intake of high dose of erythritol can increase the blood glucose level in the mice,and the mechanism may be that it affects the tricarboxylic acid cycle by interfering with riboflavin metabolism and interferes with sphingolipid metabolism,leading to impairment of the blood glucose control system.

Objective To investigate the mutation types of colorectal neuroendocrine tumors(NETs)and better un-derstand the pathogenesis of colorectal nets.Methods Patients undergoing colorectal NETs surgery were recruited,colorectal NETs and corresponding adjacent cancerous tissues were collected,and whole genome sequencing(WGS)was performed and further deeply analyzed.Results WGS sequencing showed that the mutation types of colorectal NETs included single nucleotide mutations,insertion and deletion mutations(InDel,less than 50 bp in length),copy number variations(CNV),and large structural variations(SV,more than 50 bp in length),such as insertion(INS),deletion(DEL),intra chromosomal translocation(ITX),inter chromosomal translocation(CTX)and inversion(INV).Conclusions A large number of somatic mutations occur in colorectal NETs,especially chro-mosome translocation

BACKGROUND:Osteonecrosis due to drugs is a serious adverse reaction occurring after the application of such drugs.Increasing evidence suggests that the gut microbiota composition is associated with osteonecrosis due to drugs.However,the causal relationship of the gut microbiota to osteonecrosis due to drugs is still unclear. OBJECTIVE:To evaluate the potential causal relationship between the gut microbiota and the risk of osteonecrosis due to drugs using the Mendelian randomization method. METHODS:A two-sample Mendelian randomization study was performed using the summary statistics of gut microbiota from the largest available genome-wide association study meta-analysis(n=13 266)conducted by the MiBioGen consortium as well as the summary statistics of osteonecrosis due to drugs obtained from the FinnGen consortium R9 release data(264 cases and 377 013 controls).Inverse variance weighted,MR-Egger,weighted median,weighted model and simple model were used to examine the causal association between gut microbiota and osteonecrosis due to drugs.Sensitivity analysis was used to test whether the results of the Mendelian randomization analysis were reliable.Reverse Mendelian randomization analysis was performed on all the bacteria as an outcome for effect analysis and sensitivity analysis. RESULTS AND CONCLUSION:Inverse variance weighted estimates suggested that Lentisphaerae(phylum),Lentisphaeria(class),Melainabacteria(class),Gastranaerophilales(order),Rhodospirillales(order),Victivallales(order)and Bifidobacterium(genus)had protective causal effects on osteonecrosis due to drugs.Methanobacteria(class),Bacillales(order),Methanobacteriaceae(family),Lachnospiraceae(family),Methanobacteriales(order),Holdemania(genus),Holdemania(UCG010 group)(genus),Odoribacter(genus)and Tyzzerella3(genus)had negative causal effects on osteonecrosis due to drugs.According to the results of reverse Mendelian randomization analysis,Clostridiaceae1(family),Peptostreptococcaceae(family),Streptococcaceae(family),Clostridiumsensustricto1(genus)and Streptococcus(genus)showed negative causal effects on osteonecrosis due to drugs.However,Eisenbergiella(genus)showed protective causal effects on osteonecrosis due to drugs.None of the bidirectional sensitivity analysis revealed heterogeneity or horizontal pleiotropy.When gut microbiota were used as exposure and osteonecrosis due to drugs as the outcome,Mendelian randomization analysis found that seven bacterial traits were positively correlated to osteonecrosis due to drugs,nine bacterial traits were negatively related to osteonecrosis due to drugs.When osteonecrosis due to drugs were used as exposure and gut microbiota as the outcome,reverse Mendelian randomization analysis found a negative correlated relationship with five bacterial traits and a positive causal relationship with one bacterial trait.By changing the diversity and composition of gut microbiota,it is expected to improve the incidence and prognosis of osteonecrosis due to drugs,providing new ideas for the study of orthopedic diseases.

BACKGROUND:Our previous studies found that the polypeptide of Cornus cervi Colla can promote bone growth,which has a good application prospect in the treatment of bone diseases.However,how Cornus cervi Colla works in the body and the principle are not clear. OBJECTIVE:To study the in vivo distribution and tracing of Cornus cervi Colla using fluorescence labeling and tracer technique. METHODS:Cornus cervi Colla was fluorescently labeled using fluorescein isothiocyanate,and the labeling results were detected by fluorescence imaging and UV spectral scanning.Successfully labeled Cornus cervi Colla was injected into mice by gavage,and the absorption of Cornus cervi Colla into blood was detected by laser confocal microscopy,and the distribution of Cornus cervi Colla in mice was detected by small animal in vivo imager.The distribution of Cornus cervi Colla in the mice was detected by laser confocal microscopy.Samples were taken from serum and bone at the time of the strongest fluorescence,and gel electrophoresis was carried out on serum and bone tissue protein solutions,and the components of Cornus cervi Colla absorbed into target organs were determined by secondary mass spectrometry. RESULTS AND CONCLUSION:The fluorescent markers were successfully separated by dextran gel chromatography,and the fluorescence imaging and ultraviolet spectrum scanning proved that the labeling was successful,and the fluorescence substitution degree of FITC-labeled Cornus cervi Colla was 0.953%.The fluorescence intensity of the components of Cornus cervi Colla in the blood showed that Cornus cervi Colla was most distributed in serum after oral administration for 2 hours.The fluorescence images of mice at different times were the same as those of bilateral femur and tibia,indicating that Cornus cervi Colla could play a role by entering the bone.Compared with UniProt database,secondary mass spectrometry showed that the peptide was a characteristic fragment of decorin.It is proved that decorin in Cornus cervi Colla can enter the bone to play a therapeutic role.