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The national health industry standard (WS/T 610-2018), 'the reference of screening for elevated blood pressure among children and adolescents aged 7-to 18-years-old’, plays a significant role in the standardization of the blood pressure evaluation, the early detection of high blood pressure, and the early intervention of hypertension and other chronic non-communicable diseases among Chinese children and adolescents. This standard gives screening thresholds for blood pressure assessment of children and adolescents in different genders, ages, and heights. Given the complexity of applying this standard, it is error-prone and less efficient to evaluate blood pressure one by one or program this procedure. Therefore, this study provides a SPSS package based on the standard for researchers to download and use, combined with specific cases to guide the use of this package to evaluate the blood pressure of children and adolescents step by step, which could empower researchers to accurately and efficiently conduct blood pressure screening for children and adolescents in China.
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Objective@#To analyze the prevalence of physical fitness among Chinese Han students aged 13-18 years in 2014, and explore related influencing factors.@*Methods@#This study recruited 106 881 Han students aged 13-18 years who had taken physical fitness test from Chinese National Survey on Students' Constitution and Health in 2014. After the exclusion of 1 047 students without complete records of physical fitness test, 105 834 students were included in the final analysis. According to the National Student Physical Health Standard modified in 2014, seven indicators including body mass index, vital capacity, 50-m run, sit-and-reach, standing broad jump, pull-ups/curl-ups and endurance run were tested to calculate the total score of students' physical fitness. Students with score ≥60 were regarded as qualified students. Multivariate non-conditional logistic regression model was used to analyze influencing factors of physical fitness.@*Results@#Among Chinese Han students aged 13-18 years, the total score was 70.1±10.7 and the qualified rate was 83.9% (n=88 813). Boys (83.5% (44 197/52 910)) had a lower qualified rate of physical fitness than girls (84.3% (44 616/52 924)) (P<0.001), and 13-15 age group (86.5% (46 255/53 465)) was higher than the 16–18 age group (81.3% (42 558/52 369)) (P<0.001). Except for 16–18-year-old boys from central region, normal body mass index, eastern region, good socioeconomic status, enough PE class, exercise time ≥1 h/d, homework time ≥2 h/d, TV time <1 h/d were all related to high qualified rates of physical fitness (P<0.05).@*Conclusion@#Chinese Han students aged 13-18 years were in good physical condition. The qualified rates of physical fitness were significantly different by gender and age groups. Nutritional status, region, socioeconomic status, PE class, exercise time per day, homework time per day, and TV time per day were related factors of physical fitness.
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Objective@#To investigate the prevalence and related factors of dyslipidemia among children and adolescents aged 6-17 years in 7 provinces in China.@*Methods@#Using the method of stratified cluster random sampling, 93 primary and secondary schools were selected from Guangdong, Hunan, Liaoning provinces, Shanghai, Chongqing, Tianjin municipalities and Ningxia Hui Autonomous Region in China, 2012. A total of 16 434 students aged 6-17 years old with completed physical and lipid profiles parameters were selected into this study from above 93 primary and secondary schools. Dyslipidemia was determined by the definition of Expert Advice on Prevention and Treatment of Dyslipidemia in Children and Adolescents in 2009. Logistic regression model was used to explore the factors related to dyslipidemia.@*Results@#The prevalence of elevated total cholesterol, elevated triglyceride, elevated low-density lipoprotein cholesterol, low high-density lipoprotein cholesterol, and dyslipidemia was 5.4% (887 cases), 15.7% (2 578 cases), 3.0% (492 cases), 13.5% (2 221 cases) and 28.5% (4 679 cases) among children and adolescents aged 6-17 years, respectively. Sugary drinks intake ≥once per week (OR=1.14; 95%CI: 1.05-1.24), sedentary time >10 hours per day (OR=1.14, 95%CI: 1.01-1.28), overweight (OR=1.50, 95%CI: 1.33-1.70), and obesity (OR=2.62, 95%CI: 2.31-2.96) were significantly associated with the prevalence of dyslipidemia.@*Conclusion@#The prevalence of dyslipidemia was high among children and adolescents aged 6-17 in 7 provinces in China, 2012. Sugary drinks intake ≥once per week, sedentary time >10 hours per day, overweight and obesity might be the risk factors of dyslipidemia among children and adolescents.
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Objective@#This study aimed to explore the association between malnutrition and the level of blood pressure (BP) as well as elevated BP (EBP) in Han students aged 7 to 18 years in China.@*Methods@#170 037 subjects with normal nutritional status and malnutrition were enrolled in this study from 2014 Chinese National Surveys on Students' Constitution and Health with a multi-stage stratified cluster random sampling framework covering 31 provinces, autonomous regions and municipalities after the exclusion of 44 317 overweight and obese students. According to the standard of "Screening Standard for Malnutrition of School-age Children and Adolescents" (WS/T456-2014), the nutritional status of children were classified into two categories, normal nutritional status and malnutrition containing stunting, mild wasting and moderate severe wasting. The level of BP and prevalence of EBP were compared between students with normal nutritional status and malnutrition. The multivariate logistic regression model was used to analyze the association between malnutrition and EBP.@*Results@#The levels of systolic BP (SBP) and diastolic BP (DBP) in Chinese Han students aged 7-18 years who were non-overweight and non-obesity status were (103.4±12.3) and (64.7±9.5) mmHg (1 mmHg=0.133 kPa), respectively. The prevalence of EBP, systolic EBP and diastolic EBP in Chinese Han malnourished students (N=21 012) were 3.1% (n=649), 1.5% (n=324) and 2.1% (n=445), respectively, which was significantly lower than those (N=148 320) with normal nutritional status (4.5% (n=6 707), 2.6% (n=3 872) and 2.7% (n=3 959)), and the corresponding differences were statistically significant (P<0.05). The OR (95%CI) between malnutrition and EBP was 0.68 (0.62-0.73), which were 0.65 (0.58-0.72) and 0.68 (0.60-0.77) for boys and girls. The OR (95%CI) between EBP and stunting as well as mild wasting and moderate severe wasting were 0.69 (0.62-0.77), 0.63 (0.55-0.72) and 0.79 (0.60-1.05), respectively.@*Conclusion@#The level of BP and prevalence of EBP in Chinese Han students with malnutrition were lower than those with normal nutritional status. The negative correlation existed between malnutrition and EBP in Chinese Han students aged 7 to 18 years.
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Objective: To understand and analyze the current situation and secular trends for prevalence of malnutrition among Chinese children and adolescents aged 7-18 years from 2005 to 2014, and to provide important scientific basis for students' nutrition improvement.Methods: All the subjects aged 7-18 years in both sexes were sampled from 2005, 2010 and 2014 Chinese National Surveys on Students Constitution and Health.According to the new students' health standard of Screening Standard for Malnutrition of school-age children and adolescents(WS/T456-2014) in 2014 of China, the nutritional status of children in 31 provinces (autonomous regions and municipalities, excluding Hong Kong, Macao and Taiwan province) were analyzed and compared in different ages, genders, regions and provinces from 2005 to 2014.The Tibetan students was used with the data of Tibetan minority and all the other students from 30 provinces (autonomous regions, municipalities) were Han minority.Results: The prevalence of malnutrition of children and adolescents of Han minority aged 7-18 years in 2014 was 10.0%.The prevalence of malnutrition components, including stunting, mild wasting and moderate severe wasting, were 0.8%, 3.7%, and 5.5%.Compared with 2005 and 2010, the prevalence of malnutrition of Han children and adolescents in 2014 had declined with 5.0 and 2.6 percentage points, respectively, and its components had declined with 1.0, 1.8, 2.2 and 0.4, 1.1, 1.2 percentage points, respectively.The prevalence of malnutrition of 2014 in boys was higher than in girls (11.1% vs.8.9%), the rural was higher than the urban (11.0% vs.9.1%) and the west (11.7%) was higher than the east (9.0%) and the middle (9.2%).Mild wasting of Chinese children and adolescents aged 7-18 years was the main component in malnutrition and the stunting in the Han and Tibetan children and adolescents only accounted for 8.0% and 7.5%, respectively.Compared with 2005 and 2010, the prevalence of malnutrition for Chinese children and adolescents aged 7-18 years in 2014 had declined with various extents constantly, and there was a statistically significant difference among three surveys (P<0.05).Provinces (autonomous regions, municipalities) with high prevalence of malnutrition mainly concentrated in the southwest of China from 2005 to 2014.Compared with 2005 and 2010, the prevalence of malnutrition declined in 31 provinces (autonomous regions, municipalities) of China in 2014.The number of provinces (autonomous regions, municipalities) with high prevalence of malnutrition decreased constantly and increased for the number of province (autonomous regions, municipalities) with low prevalence.Conclusion: The prevalence of malnutrition among Chinese children and adolescents aged 7-18 years had declined from 2005 to 2014, but the total prevalence of malnutrition was still high.Mild wasting was the main component in malnutrition and the prevalence of stunting was low.Provinces (autonomous regions, municipalities) with high prevalence of malnutrition mainly concentrated in the southwest of China.
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Objective@#To discuss the main causes and risk factors of disability and death among current Chinese adolescents.@*Methods@#Subnational data of China from Global Burden of Disease Study 2015 (GBD 2015) was used to rank the causes and risk factors leading to death and disability adjusted life years (DALY) in Chinese adolescents aged between 10 and 19 years old, and thereby to analyze the main cauese and risk factors of death and DALY among Chinese adolescents in different genders.@*Results@#In 2015, among Chinese adolescents aged 10-19 years old, the total DALY was 13 million 490 thousand years, and the total number of deaths was 63 258 cases. The top 3 causes of DALY were skin and subcutaneous diseases, iron-deficiency anemia and road injuries, resulting in DALY (constituent ratio) of 1 411 (10.5%), 1 094 (8.1%) and 1 029 (7.6%) thousand years respectively. The top 3 causes of death were road injuries, drowning and leukemia, causing 13 881 (21.9%), 9 895 (15.6%) and 4 620 (7.3%) deaths (constituent ratio) respectively. The top 3 risk factors of DALY were iron deficiency, alcohol use and drug use, causing 1 094 (8.1%), 487 (3.6%) and 220 thousand years (1.6%) DALY (constituent ratio) respectively. The top 3 risk factors of death were alcohol use, occupational injuries and drug use, causing 5 957 (9.4%), 1 523 (2.4%) and 810 (1.3%) deaths respectively.@*Conclusion@#Unintentional injury was the top cause of DALY and death in Chinese adolescents, followed by skin and subcutaneous diseases and iron-deficiency anemia. Iron deficiency and alcohol use were the top two risk factors of DALY and death.
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Objective@#To investigate the associations between the appendicular skeletal muscle mass index and main anthropometric parameters, and to provide clues for preventing the reduction of skeletal muscle mass among overweight and obese adults in China.@*Methods@#1 488 volunteered participants who resided in Beijing longer than one year, between 22 and 55 years old, with self-report BMI ≥24 kg/m2 were recruited from April to May 2014. 171 participants whose BMI ≤24 kg/m2 or with organic diseases at the first physical examination were excluded, finally 1 317 overweight/obese participants (male and female were 507, and 810, respectively) were enrolled into the present study. After measuring the anthropometric parameters and body composition by the DXA, Pearson correlation analysis and multiple linear regression models were used to analyze the associations between the appendicular skeletal muscle mass index and main anthropometric parameters.@*Results@#The average age of males and females was (35.6±8.4) and (38.2±9.4) years old, respectively. The females' mean levels of body fat percentage, BMI, waist circumference, hip circumference, and bone mineral density were (41.59±4.14)%, (29.00±3.75) kg/m2, (92.56±9.00) cm, (101.74±6.75) cm, and (1.20±0.10) g/cm2, respectively; and the males' mean levels were (34.22±4.61)%, (30.07±4.12) kg/m2, (99.63±9.49) cm, (102.93±7.28) cm, and (1.28±0.11) g/cm2, respectively. The mean level of appendicular skeletal muscle mass and skeletal muscle mass index in males were (26.98±3.88), and (8.96±1.02) kg, respectively, which were significantly higher than it in females ((18.57±2.61), and (7.26±0.83) kg, respectively) (P<0.001). For male, the correlation coefficients of skeletal muscle mass index with BMI, waist circumference, hip circumference, body fat percentage and bone mineral density were 0.814, 0.601, 0.637, 0.558, and 0.434, respectively; for female, the correlation coefficients of skeletal muscle mass index with BMI, waist circumference, hip circumference, body fat rate and bone mineral density were 0.761, 0.534, 0.585, 0.610, and 0.304, respectively. The correlations were statistically significant (P<0.001). Multiple linear regression analysis showed that the skeletal muscle mass index of male decreased with the increase of age (β=-0.01, 95%CI:-0.01-0.00) and body fat percentage (β=-0.13, 95%CI:-0.15--0.12) (P<0.05), while increased with the increase of BMI (β=0.31, 95%CI: 0.29-0.32) and bone mineral density (β=0.54, 95%CI: 0.10-1.01) (P<0.05). The skeletal muscle mass index of female decreased with the increase of age (β=-0.01, 95%CI:-0.01-0.00) and body fat percentage (β=-0.12, 95%CI:-0.14--0.12) (P<0.05), while increased with the increase of BMI (β=0.26, 95%CI: 0.25-0.28) and hip circumference (β=0.01, 95%CI: 0.00-0.02) (P<0.05).@*Conclusion@#The skeletal muscle mass index of male was higher than it of female. For male, the skeletal muscle mass index might be associated with age, BMI, body fat percentage and bone mineral density. While for female, the skeletal muscle mass index might be associated with age, BMI, body fat percentage and hip circumference.
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Objective@#To investigate the prevalence of metabolic syndrome (MS) among children and adolescents aged 10-16 years old in 7 provinces in China.@*Methods@#Using the method of stratified cluster random sampling, 93 primary and secondary schools were selected from Guangdong, Hunan, Liaoning, Shanghai, Chongqing, Tianjin, and Ningxia provinces in China. A total of 9 296 students aged 10-16 years old with complete physical and biochemical parameters were selected as the subjects of the present study from above 93 primary and secondary schools. MS was determined using the definition of 'guideline of 2010 Chinese children and adolescents MS definition and treatment’. The standardized age-sex composition of the 2010 census was used to standardize the MS detection rate of every province. Chi-square test was used to compare the difference of MS prevalence among participants with different characteristics.@*Results@#The prevalence of MS was 4.1% (384/9 296) among children and adolescents aged 10-16 years old in 7 provinces in China. The prevalence of MS among males was 5.0% (237/4 754), which was significantly higher than females (3.2%) (147/4 542) (P<0.05). Stratified by nutrition conditions, the prevalence of MS was 0, 0.6% (39/6 733), 8.9% (104/1 170), 30.0% (241/803) for thin, normal weight, overweight, and obese population, respectively. The MS prevalence increased with the increase of body mass index (BMI) (P<0.001). Stratified by provinces, the prevalence of MS was the highest in Tianjin (9.2%) and the lowest in Hunan province (0.8%).@*Conclusion@#The prevalence of MS was high among children and adolescents aged 10-16 years old in 7 provinces in China. MS prevalence among males was higher than females; MS prevalence among overweight/obese population was higher than normal weight population. The detection rate of metabolic syndrome was different in different provinces.
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Objective To explore the association between cesarean section and obesity in child and adolescent.Methods In this study,a total number of 42 758 primary and middle school students aged between 6 and 17 were selected,using the stratified cluster sampling method in 93 primary and middle schools in Hunan,Ningxia,Tianjin,Chongqing,Liaoning,Shanghai and Guangdong provinces and autonomous regions.Log-Binomial regression model was used to analyze the association between cesarean section and obesity in childhood or adolescent.Results Mean age of the subjects was (10.5±3.2) years.The overall rate of cesarean section among subjects attending primary or secondary schools was 42.3％,with 55.9％ in boys and,40.6％ in girls respectively and with difference statistically significant (P＜0.001).The rate on obesity among those that received cesarean section (17.6％) was significantly higher than those who experienced vaginal delivery (10.2％) (P＜0.001).Results from the log-binomial regression model showed that cesarean section significantly increased the risk of obesity in child and adolescent (OR=1.72,95％CI:1.63-1.82;P＜0.001).After adjusting for factors as sex,residential areas (urban or rural),feeding patterns,frequencies of milk-feeding,eating high-energy foods,eating fried foods and the levels of parental education,family income,parental obesity,physical activity levels,gestational age and birth weight etc.,the differences were still statistically significant (OR=1.48,95％ CI:1.39-1.57;P＜0.001).Conclusion The rate of cesarean section among pregnant women in China appeared high which may significantly increase the risk of obesity in child or adolescent.
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Objective To explore the association between cesarean section and obesity in child and adolescent.Methods In this study,a total number of 42 758 primary and middle school students aged between 6 and 17 were selected,using the stratified cluster sampling method in 93 primary and middle schools in Hunan,Ningxia,Tianjin,Chongqing,Liaoning,Shanghai and Guangdong provinces and autonomous regions.Log-Binomial regression model was used to analyze the association between cesarean section and obesity in childhood or adolescent.Results Mean age of the subjects was (10.5±3.2) years.The overall rate of cesarean section among subjects attending primary or secondary schools was 42.3％,with 55.9％ in boys and,40.6％ in girls respectively and with difference statistically significant (P＜0.001).The rate on obesity among those that received cesarean section (17.6％) was significantly higher than those who experienced vaginal delivery (10.2％) (P＜0.001).Results from the log-binomial regression model showed that cesarean section significantly increased the risk of obesity in child and adolescent (OR=1.72,95％CI:1.63-1.82;P＜0.001).After adjusting for factors as sex,residential areas (urban or rural),feeding patterns,frequencies of milk-feeding,eating high-energy foods,eating fried foods and the levels of parental education,family income,parental obesity,physical activity levels,gestational age and birth weight etc.,the differences were still statistically significant (OR=1.48,95％ CI:1.39-1.57;P＜0.001).Conclusion The rate of cesarean section among pregnant women in China appeared high which may significantly increase the risk of obesity in child or adolescent.
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AS a result of a better understanding,people pay increasing attention to the adverse effect of traditional Chinese medicine. Chansu as a rare Chinese traditional medicine has been widely used in clinical treatment and known to have cardiotoxicity. The mechanism and relationships with blood drug concentrations need to be elucidated urgently. Bufadienolides,whose chemical structure is similar to that of digoxigenin,are the major component of Chansu and also belong to cardiac glycosides. They show both excitation and inhibition effects on the heart. Myocardial cells can not only be excited to trigger tachycardia and rapid arrhythmias at a low dose,but inhibited to induce heart block and slow arrhythmias at a high dose. As the key regulator of intracellular energy and calcium ion concentration , Na+/K+ATPase can be inhibited by bufadienolides through a combination of alpha subunits of the enzyme , resulting in calcium overload and energy disorders in myocardial cells. This might be the main mechanism of cardiotoxicity. In this paper,the progress in experimental research of substances of cardiotoxicity,animal tests,enzyme and ion channel,lipid metabolism and ion homeostasis,correlations between pharma?cokinetics and cardiotoxicity are reviewed.
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Aim To establish an in vitro early drug cardiac tox-icity evaluation method by human embryonic stem cells derived cardiomyocytes ( hESC-CM) and real-time cell analysis Cardio (RTCA Cardio) system. Method The hESC-CM were cultured at RTCA Cardio E-Plate 96. Impedance signals from hESC-CM were analyzed for beating rate, contraction amplitude and beating rhythm irregularity to determine the optimum inoculation density and detection duration. Based on this, we used 0. 1 % DMSO to be the solvent and quinidine (0. 2, 0. 78, 3. 13, 12. 5, 50 and 100 μmol·L - 1 ) known as affecting cardiac activity to validate this method. Result The results revealed no significant changes in the cell index (CI), transient pulse patterns, beating rate and amplitude of hESC-CM. Quinidine will affect the CI and transi-ent pulse patterns of hESC-CM and decrease the beating rate and amplitude of hESC-CM when its concentration ≥3. 13 μmol · L - 1 . And this effect is concentration-dependent, the higher the concentration,the more time they need to recover beating and the more significant the beating rate and amplitude inhibition of quinidine on hESC-CM. Conclusion The method established by hESC-CM and RTCA Cardio system can detect the effect of quinidine on the contraction of hESC-CM, and this indicates that this method has the potential to be an attractive high-throughput tool for screening potential drugs in early evaluation of drug car-diotoxicity.
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OBJECTIVE To evaluate whether the tumor promoting activity syste m based on the ex-pression of 22 tumor pro motion marker genes in Bhas 42 cell transformation assay can be developed to be a new screening technique for predicting tumor promoting potential of che mical.METHODS Chose the 12-O-tetradecanoylphorbol-13-acetate (TPA)as positive che mical and use the Bhas 42 cell lines as test syste m.Define the day of seeding cells as d 0.On d 4,medium in each well was changed with the medium DF5F containing 0.05 mg·L -1 TPA or 0.5 %DMSO,after treat for 24,48 and 72 hrs,collect the cell samples.Extract the RNA fro m the cell samples and detect the expression of Ccnb1 ,Rif1 , Mc m3,Chek1 ,Jun,Fosl1 ,Hells,Vegfa,St mn1 ,Prl2c3,Scarb1 ,Phex,Orm1 ,Orm2,Nup54, Slc2a1 ,Il1 rl1 ,Rad51 ap1 ,Tfrc,Ab1 ,Car13 and Pik3r5 at different ti mepoints by RT-PCR.RESULTS Co mpared to the negative group,the expression of 3 genes was increased after treat with TPA for 24 hr which are Vegfa,Il1 rl1 and Pik3r5;the expression of 12 genes was increased after treat with TPA for 48 hr which are Chek1 ,Hells,Mc m3,Rad51 ap1 ,Vegfa,Il1 rl1 ,Prl2c3,Slc2a1 ,Tfrc,Ab1 ,St mn1 and Rif1 ;the expression of 10 genes was increased after treat with TPA for 72 hr which are Chek1 ,Hells, Rad51 ap1 ,Vegfa,Il1 rl1 ,Prl2c3,Slc2a1 ,Tfrc,St mn1 and Ccnb1 .CONCLUSION The 22 tumor pro-motion marker genes showed different sensitivity to the positive control che mical at different ti mepoints after treat with TPA.The result was consistent with the pro motion activity of TPA.The 22 tumor pro motion marker genes combined with the Bhas 42 cell transformation assay can be developed to be a new screening technique for predicting tumor promoting potential of che mical.
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OBJECTlVE To establish a real-time cell analysis system ( RTCA) for early drug car-diotoxicity evaluation. METHODS An in vitro drug cardiotoxicity evaluation method was established using RTCA Cardio system and primary cultured cardiomyocytes of neonatal rats. The beating rate, am-plitude and beating rhythm irregularity ( BRl ) of cardiomyocytes were observered after antiarrhythmic drugs, such as quinidine and lidocaine were added, to assess the effect of the above method on cardio-toxicity evaluation. RESULTS RTCA Cardo E-Plate 96 was inoculated with primary cultured cardiomyo-cytes that began to beat after 24 h and beat regularly after 48 h. The stable beating was maintained for a minimum of three days. The beating of cardiomyocytes decreased rapidly from 155±5 to 0 after incuba-tion with quinidine. The beating recovered gradually after 6 h. Quinidine at 3.1μmol·L-1 caused the beat-ing rate to return to 124±16. Quinidine allowed the beating rate to return to normal when the concentra-tion was less than 100.0μmol·L-1 . The beating rate, amplitude and BRl of cardiomyocytes changed in a concentration-dependent manner when incubating with lidocaine. The higher the concentration, the more significant the inhibition of lidocaine on cardiomyocytes. CONCLUSlON The cardiotoxicity of quinidine and lidocaine can be detected accurately using RTCA Cardio system, suggesting that this system can be used in early evaluation of drug cardiotoxicity.
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OBJECTlVE To investigate the action mechanism of antidepressant fluoxetine on hERG ( ether-a-go-go-related gene ) potassium channel, and the effect of protein kinase C ( PKC ) agonist phorbol-12-myristate-13-acetate ( PMA) on fluoxetine inhibition. METHODS The whole cell patch clamp technique was used to record the change in hERG potassium current ( IKr ) on HEK293 cells that stably expressed hERG potassium channel ( hERG-HEK293 steady-state cells) , which was treated with fluoxe-tine 0.01, 0.1, 1 and 10μmol·L-1 , to study the concentration-and voltage-dependence of the effects on IKr, and to observe the changes in activation, inactivation and recovery dynamics of hERG potassium channel treated with fluoxetine 1μmol·L-1 . On this basis, the effect of PMA of 1μmol·L-1 on inhibition of fluoxetine 1 μmol·L-1 was explored. RESULTS Fluoxetine 0.01, 0.1, 1 and 10 μmol·L-1 inhibited IKr on hERG-HEK293 steady-state cells in a concentration- and voltage-dependent manner. The half maximal inhibitory concentration ( lC50 ) was about 0. 8 mmol·L-1 , and the Hill coefficient was about 1. 1. Fluoxetine 1 μmol·L-1 could reduce the activation, deactivation and recovery currents of IKr and affect the activation and recovery of hERG potassium channel. After fluoxetine inhibition of IKr became stable, PMA 1 μmol·L-1 could inhibit the blocking effect of fluoxetine on hERG potassium channels. CONCLUSlON Fluoxetine has obvious inhibitory effect on IKr of hERG-HEK293 steady-state cells, but the effect could be inhibited by PKC agonist PMA.
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Human embryonic stem ceIIs(hESC),characterized by unique capacities of seIf-renewaI and differentiation into cardiomyocytes and hepatocytes,can be used in new drug screening and drug safety evaIuation processes. Cardiotoxicity and hepatotoxicity are major obstacIes to deveIopment and marketing of new drugs. hESC-derived cardiomyocytes and hepatocytes have structuraI and functionaI characteristics,which can be used for cardiotoxicity and hepatotoxicity testing in vitroand for buiIding a drug safety evaIuation system invitrothat has the advantage of short experiment cycIes,smaII dose,Iow cost and few species differences. hESC-derived cardiomyocytes and hepatocytes have broad prospects of appIication in toxicoIogy.