1. Cytochrome P450 3A4 (CYP3A4) is an important member of the cytochrome P450 enzyme superfamily, with 33 allelic variants reported previously. Genetic polymorphisms of CYP3A4 can produce a significant effect on the efficacy and safety of some drugs, so the purpose of this study was to clarify the catalytic characteristics of 22 CYP3A4 allelic isoforms, including 6 novel variants in Han Chinese population, on the oxidative metabolism of amiodarone in vitro.
2. Wild-type CYP3A4*1 and other variants expressed by insect cells system were incubated respectively with 10–500?μM substrate for 40?min at 37?°C and terminated at ?80?°C immediately. Then these samples were treated as required and detected with ultra-performance liquid chromatography-tandem mass spectrometry used to analyze its major metabolite desethylamiodarone.
3. Among the 21 CYP3A4 variants, compared with the wild-type, the intrinsic clearance values (Vmax/Km) of two variants were apparently decreased (11.07 and 2.67% relative clearance) while twelve variants revealed markedly increased values (155.20~435.96%), and the remaining of seven variants exhibited no significant changes in enzyme activity.
4. This is the first time report describing all these infrequent alleles for amiodarone metabolism, which can provide fundamental data for further clinical studies on CYP3A4 alleles. 相似文献
AIM:To determine the role of heparanase-1(HPSE-1)in orbital rhabdomyosarcoma(RMS),and to investigate the feasibility of HPSE-1 targeted therapy for RMS.METHODS:Immunohistochemistry was performed to analyze HPSE-1 expression in 51 cases of orbital RMS patients(including 28 cases of embryonal RMS and 23 cases of alveolar RMS),among whom there were 27 treated and 24 untreated with preoperative chemoradiotherapy.In vitro,studies were conducted to examine the effect of HPSE-1 silencing on RMS cell proliferation and tube formation of human umbilical vein endothelial cells(HUVECs).RD cells(an RMS cell line)and HUVECs were infected with HPSE-1 sh RNA lentivirus at a multiplicity of infection(MOI)of 10 and 30 separately.Real-time PCR and Western blot were applied to detect the m RNA and protein expression levels of HPSE-1.Cell viability of treated or control RD cells was evaluated by cell counting kit-8(CCK-8)assay.Matrigel tube formation assay was used to evaluate the effect of HPSE-1 RNAi on the tube formation of HUVECs.RESULTS:Immunohistochemistry showed that the expression rate of HPSE-1 protein was 92.9%in orbital embr yonal RMS and 91.3%in orbital alveolar RMS.Tissue from alveolar orbital RMS did not show relatively stronger staining than that from the embryonal orbital RMS.However,despite the types of RMS,comparing the cases treated chemoradiotherapy with those untreated,we have observed that chemoradiotherapy resulted in weaker staining in patients’tissues.The expression levels of HPSE-1 declined significantly in both the m RNA and protein levels in HPSE-1 sh RNA transfected RD cells.The CCK-8 assay showed that lentivirus-mediated HPSE-1 silencing resulted in significantly reduced RD cells viability in vitro.Silencing HPSE-1 expression also inhibited VEGF-induced tube formation of HUVECs in Matrigel.CONCLUSION:HPSE-1 silencing may be a promising therapy for the inhibition of orbital RMS progression. 相似文献
Background and aimsObservational studies have associated resting heart rate with incident diabetes. Whether the associations are causal remains unclear. We aimed to examine the shape and strength of the associations and assessed the causal relevance of such associations in Chinese adults.Methods and resultsThe China Kadoorie Biobank enrolled 512,891 adults in China. Cox proportional hazard regression models was conducted to estimate hazard ratios (HRs) for the associations of resting heart rate with type 2 diabetes and total diabetes. Among 92,724 participants, 36 single-nucleotide polymorphisms (SNPs) related to resting heart rate were used to construct genetic risk score. We used Mendelian randomization analyses to make the causal inferences. During a median follow-up of 9 years, 7872 incident type 2 diabetes and 13,349 incident total diabetes were documented. After regression dilution bias adjustment, each 10 bpm higher heart rate was associated with about a 26% higher risk of type 2 diabetes (HR, 1.26 [95% CI, 1.23, 1.29]) and 23% higher risk of total diabetes (HR, 1.23 [95% CI, 1.20, 1.26]). Instrumental variable analyses showed participants at top quintile compared with those at bottom quintile had 30% higher risk for type 2 diabetes (HR, 1.30 [95% CI, 1.17, 1.43]), and 10% higher risk for total diabetes (HR, 1.10 [95% CI, 1.02, 1.20]).ConclusionsThis study provides evidence that resting heart rate is an important risk factor for diabetes risk. The results suggest that novel treatment approaches targeting reduction of high heart rate for incidence of diabetes may be worth further investigation. 相似文献