AIM To study the relation between the antiarrthymic effect and the inhibition of slow reaction cardiomyocyte of ethacizine(EC). METHODS The beating rate and action potentials of cultured slow response cardiomyocyte from neonatal rats was recorded. RESULTS EC 0 1～5 0 ?mol?L -1 produced a concentration dependent suppressing effect on spontaneous beating rate of cultured cardiac cells with IC 50 of 0 17 ?mol?L -1 and the maximal inhibitory rate was 52%.The steady state of inhibition to beating rate was achieved after adding EC for 15～30 min. The effective inhibition of beating rate by EC lasted for over 1 h.As EC 2 5 ?mol?L -1 depressed beating rate to the steady state ,effects of CaCl 2 2 mmol?L -1 and Iso 1 ?mol?L -1 on beating rate were partially reduced,and the effect of aconitine 0 2 mg?L -1 was abolished. EC 0 3～2 5 ?mol?L -1 pruduced the concentration dependent depression on APA,V max ,OS,SP 4 and MDP,and prolongation of SCL of the slow response action potentials.APD 90 was also lengthened at the concentration of EC 0 9～2 5 ?mol?L -1 . CONCLUSIONS The effective depression of EC on abnormal automaticity and conductance of the slow response cardiomyocyte in heart ischemic zone may be an important mechanism for its effective termination on some arrhythimas.EC may depress Ca 2+ ,especially Na + currents on slow response cardiomyocyte.

Aim To investigate whether pioglitazone has protective effect against glutamate induced neurotoxicity in cultured cortical neurons and its possible molecular mechanisms underlying pioglitazone's neuroprotective effects.Methods The cortical neurons were taken from newborn rats and used for experiments 7 days after culture.The neurons were randomly divided into control group;glutamate group; glutamate+piogli-tazone group;glutamate+SP600125 group;SP600125 group.Cell viability was determined by MTT.The morphology change of neurons was observed under a fluorescence microscope with fluorescence dye Hoechst 33258.Immunostaining was used to investigate the expression of phospho-ATF2 in neuronal cells.Western blot was performed to investigate the protein level of phospho-JNK1 and total JNK1.Results Pioglitazone markedly reduced the damage of cortical neurons caused by glutamate.Pioglitazone also significantly inhibited glutamate induced up-regulation of phospho-JNK1 protein level and phospho-ATF2 expression.SP600125, an inhibitor of JNK, antagonized the toxicity induced by glutamate.Conclusions Pioglitazone can protect cultured cortical neurons from glutamate induced damage.The protective effect of pioglitazone appears to be associated with inhibiting the c-Jun N-terminal protein kinase signaling pathway.

Objective To research and construct dynamic electrocardiograph (ECG) simulation model/algorithm to simulate different kinds of clinical ECG,where the heart rate can be infinitely variable,and to develop one platform for fast-demo and analysis of theoretical wave based on this algorithm which can be implemented in ECG training and teaching. Methods According to different characteristics decoupled one complete ECG wave to 4 parts,including P-wave,PR-section,QT -wave and TP -section. P -wave and QT -wave database were set up accordingly to find the relationship algorithm between PR-section and heart rate,TP-section and heart rate. With the synthesis work of the algorithm and clinical diagnosis theory,ECG simulation mathematical model /algorithm,dynamic link library.(dll) and software interface were developed by C++. Results Through comparing the ECG simulation results with clinical samples,the veracity and validity of the mathematical model/algorithm was verified. Conclusion The software module based on this model/algorithm is very valuable for ECG training and teaching in clinic,and can be implemented in the development of more advanced ECG relative software and devices.

Objective To investigate the effect of rapid rehabilitation nursing mode on postoperative complications in elderly patients with appendicitis. Methods Forty-eight elderly patients with appendicitis underwent surgery from July 2013 to June 2014 were set as the control group, and another fifty-three elderly patients from July 2014 to June 2015 as observation group. The patients in the control group were treated with routine care while the patients in the observation group with rapid rehabilitation nursing. Operative complications, gastrointestinal tumor recovery and postoperative hospitalization time were compared within one week after the operations between two groups. Result The rates of constipation, abdominal distention, chills and dysuria in the observation group were significantly lower than those of the control and the time of anal first exhaust, defecation and postoperative hospitalization in the observation group were significantly lower or shorter than those in the control group (all P<0.05). Conclusion The rapid rehabilitation nursing mode based on evidence can reduce surgery complications in elderly patients, promoter recovery and shorten hospitalization time.

Objective: To explore the effectiveness of machine learning algorithms in predicting non-suicidal self-injury (NSSI) behavior among college students, and to analyze the influencing factors of NSSI behavior, thus providing a reference for promoting psychological well-being. Methods: In December 2022, a stratified random cluster sampling method was used to select 835 college students from a university in Guizhou Province, China. The Adolescent Self-injury Scale, Family Function Assessment Scale, and Emotion Regulation Self-efficacy Scale were used to evaluate the participants. Demographic characteristics, family factors, and emotional factors were taken as independent variables, while the dependent variable was whether college students exhibited NSSI behavior. Machine learning algorithms, including Logistic regression, support vector machine (SVM), decision trees, algorithm gradient boosting trees, random forests, and AdaBoost, were used to construct predictive models. Results: The detection rate of NSSI behavior among the college students was 23.23% (194 individuals). The NSSI behavior group scored higher than the non-NSSI behavior group in total family function, emotional communication, egoism, and family rules ( t=3.02, 3.35 , 2.23,2.87, P <0.05). On the other hand, the non-NSSI behavior group scored higher than the NSSI behavior group in total emotion regulation selfefficacy, managing negative emotion self-efficacy, and expressing positive emotion self-efficacy ( t=-5.04, -5.48 , -2.43, P <0.05). The recall rates of random forests, SVM, Logistic regression, decision trees, algorithm gradient boosting trees, and AdaBoost were 84.3% , 90.6%, 73.4%, 87.5%, 95.3%, 89.0%, respectively. The F1 scores were 84.4%, 92.1%, 71.2 %, 79.4%, 91.7%, 89.1% , respectively. The respective precision rates were 84.4%, 93.5%, 69.1%, 72.7%, 88.4%, 89.1 %. The AUC scores were 0.845, 0.922, 0.706, 0.776, 0.915, and 0.891, respectively. Conclusion Compared to the algorithm gradient boosting tree, random forest, Logistic regression, and AdaBoost models, the SVM model has a better predictive effect on whether college students in Guizhou Province exhibits NSSI behavior. It is recommended to use an appropriate model to identify students at risk of NSSI behavior as early as possible and provide psychological crisis interventions to promote their mental health.

At present, 2019 novel coronavirus (2019-nCoV) mutations occur frequently, and the current mutation, represented by omicron, has significantly enhanced its transmission and greatly increased the difficulty of prevention and control of Coronavirus Disease 2019 (COVID-19). In order to effectively deal with the epidemic situation of COVID-19, it is urgent to develop accurate, sensitive and field-applicable diversified detection techniques for the mutants. In this review, we introduce the current technical method for 2019-nCoV detection, focus on the application of different method in mutation detection, and analyze their advantages and disadvantages. In addition to the traditional detection techniques such as nucleic acid and immunity, we also discuss the importance of establishing phenotypic correlation detection method such as affinity of 2019-nCoV mutants. It is meaningful for accurately detecting and analyzing the important indexes such as infectivity and pathogenicity of the mutant, as well as for improving the efficiency of epidemic screening and its treatment.

OBJECTIVE： To study the effects of ethyl acetate part form the ethanol extract of Periploca forrestii on cardiac function of isolated frog heart， and to primarily investigate its potential mechanism. METHODS： The isolated frog heart samples were prepared by using the intube method of steinmann. The Ren’s solution （blank control）， 1.70 mg/mL and 3.48 mg/mL ethyl acetate part from ethanol extract of P. forrestii were used to perfuse the sample. The BL-420 biological function experimental system was used to record the changes in heart rate and myocardial contractility. The effects of ethyl acetate part from ethanol extract of P. forrestii on cardiac function of isolated frog heart were investigated. After perfused with 10 mg/L atropine， 20 μL isoproterenol， 1 μL low calcium （per 1 000 mL pure water contain 0.06 g CaCl2）， high calcium Ren’s solution （per 1 000 mL pure water contain 0.24 g CaCl2）， adding 1.74 mg/mL ethyl acetate part from ethanol extract of P. forrestii， the changes of myocardial contractility in isolated hearts were recorded by BL-420 biological function experimental system. Myocardial tissue was collected after perfused with Ren’s solution （blank control） and ethyl acetate part from ethanol extract of P. forrestii with 1.74 and 3.48   mg/mL. The activity of Na+-K+-ATPase， Ca2+-Mg2+-ATPase and AChE were detected to investigate the potential mechanism of the effects of ethyl acetate extract from ethanol extract of P. forrestii on cardiac function. RESULTS： Compared with blank control， mean myocardial contractility was significantly decreased （P＜0.001） after adding 1.74， 3.48 mg/mL ethyl acetate part form ethanol extract of P. forrestii， but had no significant on heart rate （P＞0.05）. With the increase of extracellular Ca2+ concentration， the inhibitory effect of ethyl acetate part from ethanol extract of P. forrestii on isolated frog heart contraction also increased gradually. After adding atropine and isoproterenol， the inhibitory effect of the ethyl acetate part form ethanol extract of P. forrestii on isolated frog heart contraction decreased to some certain. The activity of Na+-K+-ATPase in cardiac tissue was not significantly changed （P＞0.05）， the activity of Ca2+-Mg2+-ATPase was significantly increased （P＜0.05）， and the activity of AChE was significantly decreased （P＜0.05） after perfused with 1.74， 3.48 mg/mL ethyl acetate part form ethanol extract of P. forrestii. CONCLUSIONS： The ethyl acetate part from the ethanol extract of P. forrestii can inhibit the contractile activity of the isolated frog heart and has a certain negative inotropic effect. The mechanism may be related to the increase of Ca2+-Mg2+-ATPase activity， inhibition of AChE activity， blocking of calcium channel in the cell membrane， the activation of M receptor and blocking of β receptor.

RNF20, an E3 ligase critical for monoubiquitination of histone H2B at lysine 120 (H2Bub), has been implicated in the regulation of various cellar processes; however, its physiological roles in adipocytes remain poorly characterized. Here, we report that the adipocyte-specific knockout of Rnf20 (ASKO) in mice led to progressive fat loss, organomegaly and hyperinsulinemia. Despite signs of hyperinsulinemia, normal insulin sensitivity and improved glucose tolerance were observed in the young and aged CD-fed ASKO mice. In addition, high-fat diet-fed ASKO mice developed severe liver steatosis. Moreover, we observed that the ASKO mice were extremely sensitive to a cold environment due to decreased expression levels of brown adipose tissue (BAT) selective genes, including uncoupling protein 1 (Ucp1), and impaired mitochondrial functions. Significantly decreased levels of peroxisome proliferator-activated receptor gamma (Pparγ) were observed in the gonadal white adipose tissues (gWAT) from the ASKO mice, suggesting that Rnf20 regulates adipogenesis, at least in part, through Pparγ. Rosiglitazone-treated ASKO mice exhibited increased fat mass compared to that of the non-treated ASKO mice. Collectively, our results illustrate the critical role of RNF20 in control of white and brown adipose tissue development and physiological function.