Objective： To investigate the changes of cyclin L2（CCNL2） gene mRNA and protein during the differentiation of P19 cells to cardiac myocytes, and to explore the relationship between CCNL2 gene and the differentiatio...Objective： To investigate the changes of cyclin L2（CCNL2） gene mRNA and protein during the differentiation of P19 cells to cardiac myocytes, and to explore the relationship between CCNL2 gene and the differentiation of cardiac myocytes. Methods： P19 cells were cultured with 0.9% DMSO for 18 days. Western blots of cardiac troponin I （cTnI） were used to identify cell differentiation. Total RNA was extracted from P19 cells during the process of differentiation at various time points：pre-differentiation（Day 0）, and Day 1 to Day 18. The expression levels of CCNL2 gene mRNA and protein were evaluated by RT-PCR and Western blot, respectively. Results： After being induced to differentiate by DMSO for 4 days in suspension, spontaneously and rhythmically beating ceils were seen at 8 day, which were cTnI-positive. In P19 cells, both the expression level of CCNL2 gene mRNA and protein were gradually down-regulated. Conclusion： Both the expression of CCNL2 gene and protein were down-regulated during the process of the differentiation of P19 cells into cardiac myocytes, suggesting a possible role for this cyclin in their differentiation.展开更多
Objectives Clopidogrel is a prodrug that has to be converted to an active metabolite by hepatic cytochrome P450(CYP) isoenzymes to inhibit platelet aggregation.Individualvariability of platelet inhibition by clopidogr...Objectives Clopidogrel is a prodrug that has to be converted to an active metabolite by hepatic cytochrome P450(CYP) isoenzymes to inhibit platelet aggregation.Individualvariability of platelet inhibition by clopidogrel suggests a possibility for genetic factors having a significant influence on clopidogrel responsiveness.In this study,we sought to determine the association between the single nucleotide polymorphism of CYP 2C19 681G】A and the occurrence of clopidogrel resistance(CR) in Chinese.Methods The study enrolled 614 hospitalized patients who underwentsuccessful percutaneouscoronary intervention with drug-eluting stents were received the treatmentwith dual antiplatelet regimen(aspirin plus clopidogrel).All patients received loading doses of 600 mg clopidogrel and 300 mg aspirin.20μmol/L ADP-induced platelet aggregation ratio(PAR ) was assessed 24 h after clopi- dogrel administration.The maximum residual PAR≥70%was defined as CR.Genomic DNA was extracted from whole blood samples according to standard protocols,the single nucleotide polymorphism of the CYP2C19 681G】A was genotyped by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) in all the patients.Results CR was found in 126 patients(20.5%).There was CYP2C19 681G】A polymorphism in the study population.The frequencies of the three kinds of genotypes(GG,GA,A A) in CR group and non-CR (NCR)group were 32.5%,47.6%,19.8%and 48.0%, 45.0%,7.0%,respectively.The frequency of AA genotype was significantly higher in NCR group than that in CR group (OR =3.03,95%CI:1.889～5.784,P=0.003).The A allele carriers were more likely to develop clopidogrel resistance compared with that of G allele carriers(OR=1.85,95%CI: 1.392～2.459,P=0.002).Conclusions CYP2C19 681G/A polymorphism is associated with the risk of CR,and the A allele carriers may be a possible genetic susceptibility factor for patients with CR.展开更多
文摘Objective： To investigate the changes of cyclin L2（CCNL2） gene mRNA and protein during the differentiation of P19 cells to cardiac myocytes, and to explore the relationship between CCNL2 gene and the differentiation of cardiac myocytes. Methods： P19 cells were cultured with 0.9% DMSO for 18 days. Western blots of cardiac troponin I （cTnI） were used to identify cell differentiation. Total RNA was extracted from P19 cells during the process of differentiation at various time points：pre-differentiation（Day 0）, and Day 1 to Day 18. The expression levels of CCNL2 gene mRNA and protein were evaluated by RT-PCR and Western blot, respectively. Results： After being induced to differentiate by DMSO for 4 days in suspension, spontaneously and rhythmically beating ceils were seen at 8 day, which were cTnI-positive. In P19 cells, both the expression level of CCNL2 gene mRNA and protein were gradually down-regulated. Conclusion： Both the expression of CCNL2 gene and protein were down-regulated during the process of the differentiation of P19 cells into cardiac myocytes, suggesting a possible role for this cyclin in their differentiation.
文摘Objectives Clopidogrel is a prodrug that has to be converted to an active metabolite by hepatic cytochrome P450(CYP) isoenzymes to inhibit platelet aggregation.Individualvariability of platelet inhibition by clopidogrel suggests a possibility for genetic factors having a significant influence on clopidogrel responsiveness.In this study,we sought to determine the association between the single nucleotide polymorphism of CYP 2C19 681G】A and the occurrence of clopidogrel resistance(CR) in Chinese.Methods The study enrolled 614 hospitalized patients who underwentsuccessful percutaneouscoronary intervention with drug-eluting stents were received the treatmentwith dual antiplatelet regimen(aspirin plus clopidogrel).All patients received loading doses of 600 mg clopidogrel and 300 mg aspirin.20μmol/L ADP-induced platelet aggregation ratio(PAR ) was assessed 24 h after clopi- dogrel administration.The maximum residual PAR≥70%was defined as CR.Genomic DNA was extracted from whole blood samples according to standard protocols,the single nucleotide polymorphism of the CYP2C19 681G】A was genotyped by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) in all the patients.Results CR was found in 126 patients(20.5%).There was CYP2C19 681G】A polymorphism in the study population.The frequencies of the three kinds of genotypes(GG,GA,A A) in CR group and non-CR (NCR)group were 32.5%,47.6%,19.8%and 48.0%, 45.0%,7.0%,respectively.The frequency of AA genotype was significantly higher in NCR group than that in CR group (OR =3.03,95%CI:1.889～5.784,P=0.003).The A allele carriers were more likely to develop clopidogrel resistance compared with that of G allele carriers(OR=1.85,95%CI: 1.392～2.459,P=0.002).Conclusions CYP2C19 681G/A polymorphism is associated with the risk of CR,and the A allele carriers may be a possible genetic susceptibility factor for patients with CR.
