Melatonin (Mel) has been shown to have cardioprotective effects, but its action on ion channels is unclear. In this experiment, we investigated the inhibitory effect of Mel on late sodium currents (I_Na.L) in mouse ventricular myocytes and the anti-arrhythmic effect at the organ level as well as its mechanism. The whole-cell patch clamp technique was applied to record the ionic currents and action potential (AP) in mouse ventricular myocytes while the electrocardiogram (ECG) and monophasic action potential (MAP) were recorded simultaneously in mouse hearts using a multichannel acquisition and analysis system. The results demonstrated that the half maximal inhibitory concentration (IC₅₀) values of Mel on transient sodium current (I_Na.T) and specific I_Na.L opener 2 nmol·L^-1 sea anemone toxins II (ATX II) increased I_Na.L were 686.615 and 7.37 μmol·L^-1, respectively. Mel did not affect L-type calcium current (I_Ca.L), transient outward current (I_to), and AP. In addition, 16 μmol·L^-1 Mel shortened ATX II-prolonged action potential duration (APD), suppressed ATX II-induced early afterdepolarizations (EADs), and significantly reduced the incidence of ventricular tachycardia (VT) and ventricular fibrillation (VF) in Langendorff-perfused mouse hearts. In conclusion, Mel exerted its antiarrhythmic effects principally by blocking I_Na.L, thus providing a significant theoretical basis for new clinical applications of Mel. Animal welfare and experimental process are in accordance with the regulations of the Experimental Animal Ethics Committee of Wuhan University of Science and Technology (2023130).

Objective To investigate the effect of fluid shear(FS)on apoptosis of glomerular epithelial cells(GECs)and the role of Piezo 1 protein in it.Methods GECs(glomerular epithelial cells)of SD rat were cul-tured.Fluid shear stimulation was simulated by a Flexcell-T5000 tensiometer.Apoptosis level was detected by flow cytometry.The expression of Piezo 1 proteins in GECs was detected by immunofluorescence staining.The activating of Piezo 1 channels by fluid shear was observed using Ca2+indicator(Cal-590 AM).The effect of Piezo 1 on apop-tosis in GECs was analyzed after modulating the function or expression of Piezo 1 protein using the chemical activa-tor Yoda1,the inhibitor GsMtx 4 was regulated by lentivirus Lv-shPiezo 1.Results Compared with the blank controlgroup,apoptosis increased in the fluid shear group(P＜0.05).The rate of apoptosis increased with the enhancing of fluid shear strength;Piezo 1 was commonly expressed in GECs.Fluid shear activated Piezo 1 chan-nel and enhanced expression of Piezo 1.The agonist Yoda1 promoted the apoptosis of GECs GsMtx 4 inhibited the apoptosis induced by fluid shear.Lv-shPiezo 1 knocked down the expression of Piezo 1 in GECs and the apoptosis rate of GECs in the knockdown group was reduced as compared to that in the control group and Lv-Ctrl group(P＜0.05).Conclusions Fluid shear may promote apoptosis of GECs by activation of Piezo 1 and by enhancing expression of Piezo 1.

This study using maltodextrin as raw material, 1%-5% polyvinylpyrrolidone K30 as template agent, 1%-5% ammonium bicarbonate as pore-forming agent, curcumin and ibuprofen as model drugs. Porous maltodextrin was prepared by template and pore-forming agent methods, respectively. The structure and drug delivery behavior of porous maltodextrin prepared by different technologies were comprehensively characterized. The results showed that the porous maltodextrin prepared by pore-forming agent method had larger specific surface area (6.449 4 m²·g^-1) and pore size (32.804 2 nm), which was significantly better than that by template agent method (3.670 2 m²·g^-1, 15.278 5 nm). The adsorption kinetics between porous maltodextrin prepared by pore-forming agent method and curcumin were suitable for quasi-first order adsorption kinetic model, and that between porous maltodextrin and ibuprofen were suitable for quasi-second order adsorption kinetic model. While the adsorption kinetics between porous maltodextrin prepared by template agent method and two model drugs were both suitable for the quasi-first order adsorption kinetic model. In addition, the dissolution behavior analysis showed that the porous maltodextrin prepared by the two technologies can significantly improve the dissolution behavior of insoluble drugs, and the drug release was both carried out by diffusion mechanism, which suitable for the Peppas kinetic release model, but the porous maltodextrin prepared by template agent method had a faster release rate. The change of nozzle diameter had no significant effect on the adsorption process and drug release behavior of porous maltodextrin. In conclusion, the porous maltodextrins prepared by two different technologies were both beneficial to the delivery of insoluble drugs, and the template agent method was the best for delivery of insoluble drugs. This study can provide theoretical basis for the preparation of porous particles, promote the application of porous particles in insoluble drugs, and improve the bioavailability of insoluble drugs.

Objective To investigate the correlation between qi stagnation and phlegm stasis syndrome in the young and middle-aged population and the detection rate of thyroid nodules.Methods The clinical data of those who participated in the questionnaire survey and took thyroid ultrasonography at Dongguan Hospital of Guangzhou University of Chinese Medicine from June 1 to December 1,2023 were collected.The clinical information covered age,gender,family history,body mass index(BMI),related symptoms,and ultrasonographic findings.And then the related data were statistically analyzed.Results(1)The clinical data of 196 cases were collected,of which 65 cases(33.16%)suffered from thyroid nodules,50 cases(25.51%)were differentiated as qi stagnation and phlegm stasis syndrome,53 cases(27.04%)had qi depression constitution of traditional Chinese medicine(TCM),55 cases(28.06%)had blood stasis constitution,and 48 cases(24.49%)had phlegm-dampness constitution.(2)The results of univariate analysis showed that the relevant factors for thyroid nodules included female,family history,qi stagnation and phlegm stasis syndrome,qi depression constitution,blood stasis constitution,phlegm-dampness constitution,dizziness and headache,neck stiffness,swallowing discomfort,lump on the surface of the body,dysmenorrhea and amenorrhea,tightness in the chest,distending pain in hypochondrium,depressed in spirits,emotional vulnerability,distending pain in breast,gloomy complexion,darkish lips,dark circles around the eyes,heaviness of the body,eyelid edema,and profuse sputum,and the differences were all statistically significant(P＜0.05 or P＜0.01).(3)Multivariate Logistic regression analysis was performed on the basis of univariate analysis,and the results showed that qi stagnation and phlegm stasis syndrome(OR:4.03,95%CI:1.85-8.77),phlegm-dampness constitution(OR:4.68,95%CI:2.06-10.63),and lump on the surface of the body(OR:2.97,95%CI:1.11-7.95)were the influencing factors for thyroid nodules.(4)A prediction model for detecting thyroid nodules was constructed:logit(P)=-1.607+1.39×qi stagnation and phlegm stasis syndrome(0 expressing absence,1 expressing presence)+1.54×phlegm-dampness constitution(0 expressing absence,1 expressing presence)+1.09×lump on the surface of the body(0 expressing absence,1 expressing presence).The model was evaluated by using the receiver operating characteristic(ROC)curve,and the area under the curve(AUC)was 0.75(95%CI:0.67-0.83,P＜0.001).Conclusion In the young and middle-aged population,qi stagnation and phlegm stasis are the risk factors for the detectable rate of thyroid nodules.The early identification,risk prediction and timely intervention for the population with qi stagnation and phlegm stasis will be helpful for the prevention and treatment of thyroid nodules.

This research established a high-performance liquid chromatography(HPLC) method for simultaneous determination of isoorientin, orientin, vitexin, and isovitexin in Commelina communis to conduct content difference analysis and quality evaluation of 62 batches of C. communis from different origins. The HPLC content determination was performed on a Dikma Platisil ODS chromatographic column(4.6 mm×250 mm, 5 μm), with acetonitrile-0.1% formic acid(14∶86) as the mobile phase. The detection wavelength was set at 348 nm, the flow rate was 1.0 mL·min~(-1), and the column temperature was 35 ℃. The differences in origins and quality of 62 batches of C. communis were studied by chemometrics. The results showed that the determination of four components mani-fested a good linear relationship in the range of mass concentration(r>0.999 9), and the average recovery rate was 96.17%-103.0%. The relative standard deviations(RSDs) of precision, stability, and repeatability were all less than 2.0%. The content of four components from high to low was isoorientin>isovitexin>orientin>vitexin. Forty-seven batches of C. communis with clear origins were classified into six categories by chemometrics. C. communis from different origins had different qualities. Generally, C. communis from Western China, Central China, and South of China had superior qualities. The HPLC method established in this study is specific, simple, and efficient, which provides references for the comprehensive evaluation of the quality of C. communis. The chemometrics shows that the qualities of C. communis from different origins are largely different. Isoorientin can be used as an index to determine the content of C. communis, and its content limit should be set no less than 0.023%.
Commelina ; Chemometrics ; Drugs, Chinese Herbal/chemistry* ; China ; Chromatography, High Pressure Liquid/methods*

Paris rugosa(Melanthiaceae) only grows in Yunnan province of China at present, and its chemical constituents have not been systematically studied. In this study, nine compounds, including one new compound pariposide G(1) and eight known compounds of cerin(2), stigmast-4-en-3-one(3), β-ecdysone(4), ophiopogonin C'(5), methyl protogracillin(6), gracillin(7), parissaponin H(8), and parisyunnanoside G(9), were isolated and identified from the ethanol extract of P. rugosa rhizomes by column chromatography methods and semi-preparative high-performance liquid chromatography(HPLC). Compounds 1-9 were isolated from this plant for the first time. The antibacterial and antifungal activities of all the compounds were evaluated. The results showed that ophiopogonin C' had strong inhibitory effects on Candida albicans [MIC_(90)=(4.68±0.01) μmol·L~(-1)] and the fluconazole-resistant strain of C. albicans [MIC_(90)=(4.66±0.02) μmol·L~(-1)].
Anti-Bacterial Agents ; Candida albicans ; China ; Liliaceae ; Melanthiaceae ; Rhizome

Objective:To compare the self-evaluated learning behavior and achievement of eight-year-program clinical medical students on online and offline problem-based learning (PBL), and to provide references and suggestions for successful implementation of online PBL teaching.Methods:During the three semesters of September 2020 to January 2022, a survey was performed on 100 clinical medical students of 2018 eight-year program on online or offline PBL teaching in Xiangya School of Medicine, Central South University. At the end of PBL courses, the students received questionnaires to self-assess their learning behavior and achievement in online or offline PBL teaching. The data were analyzed using the paired rank sum test with the use of SPSS 26.0.Results:Before class, there were no significant differences in learning behaviors including preparation time, communication with classmates, and materials collecting and sorting between students on online and offline PBL teaching ( P>0.05). In class, no significant differences were found in students' initiative of speaking and degree of satisfaction with classmates' speaking between online and offline teaching ( P>0.05), but the students on offline teaching showed significantly better concentration of attention ( Z=-4.24, P<0.001), listening to classmates' speeches ( Z=-3.42, P=0.001), and classmates' interaction ( Z=-3.11, P=0.002) compared with those on online teaching. No significant differences were observed between online and offline PBL teaching in students' self-evaluated learning achievements including improvements in autonomous learning ability, problem-solving ability, and literature inquiry skills ( P>0.05). Conclusion:Students on online PBL teaching have generally as good pre-class preparation and in-class learning performance as those on offline PBL teaching, indicating that the online PBL mode can be well implemented, and it can also ensure almost the same learning achievement as offline teaching.