Objective To investigate the effect of cardiotrophin-1 (CT-1) mediated by recombinant adenovirus (Adv) on the neural differentiation of bone marrow mesenchymal stem cells (rBMSCs) of rats.Methods The rBMSCs were isolated and cultured by attachment method.The surface marker protein was identified by flow cytometry.The rBMSCs were divided into 4 groups:control group,AdV enhanced green fluorescence protein (Adv-EGFP) + induction group(empty virus group),CT-1 group and induction group.The cells were transfected by Adv in the corresponding multiplicity of infections.Each group was induced by neural induction medium except for control group.The cells morphological changes were observed by microscope and the expressions of Nestin,neuronal nuclei (NeuN) and glial fibrillary acidic protein(GFAP) were detected respectively by cellular immunofluorescence at 5 h,3 d and 7 d after induction.Results After induction treatment,neuron-like cells morphological changes were observed in all the groups except for control group,among which the most obvious change was found in CT-1 group.The positive rate of Nestin was the highest at 5 h after induction.Positive rate of CT-1 group[(86.31 ± 4.27)％] was higher than any other groups,the differences were statistically significant (all P ＜ 0.001);after which its positive rate gradually declined,the positive rate of CT-1 group changed more obviously than other groups,and the differences were statistically significant (all P ＜ 0.001).The difference in Nestin positive rate between the empty virus group and induction group was not statistically significant (all P ＞ 0.05) at various time points.The NeuN and GFAP could be observed in CT-1 group at 5 h after induction.Then the positive rate of NeuN and GFAP increased gradually,and climbed to the highest point [(64.41 ± 3.65)％,(47.14 ± 4.29)％] on 7 d after induction.Positive rate of NeuN and GFAP in CT-1 group at various time points were higher than that of other groups,and the differences were statistically significant (all P ＜0.001).The difference of NeuN and GFAP positive rate between the empty virus group and induction group was not statistically significant (all P ＞ 0.05).Conclusion CT-1 could promote the neural differentiation of rBMSCs.

Objective To explore the application of nanodisc in functional and drug discovery research of G protein-coupled receptor (GPCR).Methods The purified recombinant 5-Hydroxytryptamine 2B receptor (5-HT2BR) was reconstituted into nanodisc complex.Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and size exclution chromatography were performed to evaluate the reconstitution reaction,followed by the use of surface plasmon resonance to validate the ligand-binding activity of 5-HT2BR after reconstitution.Results 5-HT2B R was effectively self-assembled into nanodisc while maintained its binding activity toward the antagonist SB204741.Conclusions The presented study provided potential application of 5-HT2B R-nanodisc for the development of subtype-selective drugs against 5-HT2B R and the fundamental of utilizing nanodisc for GPCR structural and functional studies as well as drug discovery.

Objective To analyze the serum levels of bone morphogenetic protein 4(BMP4)and nerve ax-on guidance factor 4(Netrin-4)in patients with diabetic retinopathy(DR),and to study their relationship with disease stage and prognosis.Methods A total of 186 patients with type 2 diabetes admitted to the hospi-tal from October 2019 to November 2022 were selected as the research objects.According to the presence or absence of retinopathy,they were divided into DR Group(108 cases)and non-DR group(78 cases),and 100 healthy people in the hospital were selected as the control group.According to the stage of DR,the DR pa-tients were divided into stage Ⅰ(19 cases),stage Ⅱ(14 cases),stage Ⅲ(22 cases),stage Ⅳ(23 cases),stage V(18 cases)and stage Ⅵ(12 cases).According to the visual impairment after treatment,the DR patients were divided into a good prognosis group(72 cases)and a poor prognosis group(36 cases).Serum BMP4,Ne-trin-4,fasting plasma glucose(FPG),glycated hemoglobin Alc(HbA1c),systolic blood pressure(SBP),dias-tolic blood pressure(DBP),triglyceride(TG),total cholesterol(TC),low density lipoprotein cholesterol(LDL-C),high density lipoprotein cholesterol(HDL-C)were detected by enzyme-linked immunosorbent as-say.The serum levels of BMP4 and Netrin-4 in DR patients with different disease stages were analyzed.Multi-variate Logistic regression was used to analyze the influencing factors of DR,and the serum levels of BMP4 and Netrin-4 in DR patients with different prognosis were analyzed.The receiver operating characteristic(ROC)curve was used to analyze the diagnostic value of poor prognosis in DR patients.Results The FPG,HbA1c,SBP,DBP,TG,TC,BMP4,Netrin-4 levels in DR group were higher than those in control group and non-DR group,while HDL-C level was lower than that in control group and DR group(P＜0.05).There were significant differences in serum BMP4 and Netrin-4 levels between DR patients with different disease stages(P＜0.05).HbA1c,BMP4 and Netrin-4 levels were influencing factors for the occurrence of DR(P＜0.05).The serum levels of BMP4 and Netrin-4 in the poor prognosis group were higher than those in the good prog-nosis group(P＜0.05).The combination of serum BMP4 and Netrin-4 levels in the diagnosis of poor progno-sis of DR patients was better than that of each index alone.Conclusion The serum levels of BMP4 and Ne-trin-4 are increased in DR patients,which can assist in the evaluation of the disease stage of the patients.The combination of BMP4 and Netrin-4 has a good effect in the diagnosis of poor prognosis of patients.