Novel roles of an intragenic G-quadruplex in controlling microRNA expression and cardiac function.

Simultaneous dysregulation of multiple microRNAs (miRs) affects various pathological pathways related to cardiac failure. In addition to being potential cardiac disease-specific markers, miR-23b/27b/24-1 were reported to be responsible for conferring cardiac pathophysiological processes. In this study, we identified a conserved guanine-rich RNA motif within the miR-23b/27b/24-1 cluster that can form an RNA G-quadruplex (rG4) in vitro and in cells. Disruption of this intragenic rG4 significantly increased the production of all three miRs. Conversely, a G4-binding ligand tetrandrine (TET) stabilized the rG4 and suppressed miRs production in human and rodent cardiomyocytes. Our further study showed that the rG4 prevented Drosha-DGCR8 binding and processing of the pri-miR, suppressing the biogenesis of all three miRs. Moreover, CRISPR/Cas9-mediated G4 deletion in the rat genome aberrantly elevated all three miRs in the heart in vivo, leading to cardiac contractile dysfunction. Importantly, loss of the G4 resulted in reduced targets for the aforementioned miRs critical for normal heart function and defects in the L-type Ca2+ channel-ryanodine receptor (LCC-RyR) coupling in cardiomyocytes. Our results reveal a novel mechanism for G4-dependent regulation of miR biogenesis, which is essential for maintaining normal heart function.

Biodegradable polymer drug-eluting stents versus second-generation drug-eluting stents in patients with and without diabetes mellitus: a single-center study.

BACKGROUND: To improve outcomes in patients with diabetes mellitus (DM) undergoing percutaneous coronary intervention remain an unmet clinical need. The study aimed to evaluate the efficacy and safety of G2-DESs and BP-DESs in patients with and without DM in a single center in China. METHODS: A total of 7666 consecutive patients who exclusively had G2-DES or BP-DES implantation throughout 2013 in our center were studied. The primary efficacy endpoint was any target lesion revascularization (TLR), whereas the primary safety endpoint was a composite of death or myocardial infarction (MI) at 2-year follow-up. RESULTS: G2-DESs had a similar occurrence of death, non-fatal MI, TLR, stroke, and stent thrombosis compared with BP-DESs in patients with DM (all P > 0.05). The incidence of TVR and TLR was lower for G2-DESs than for BP-DESs in patients without DM (3.2% vs. 5.1%, P = 0.002; 2.2% vs. 4.5%, P < 0.001, respectively). Kaplan-Meier analysis also showed better TVR- and TLR-free survival rates for G2-DESs than for BP-DESs in patients without DM. Multivariate analysis showed that a BP-DES was an independent risk factor for TLR (hazard ratio 1.963, 95% confidence interval 1.390-2.772, P < 0.001) in patients without DM, which was not predictive of other components of major adverse cardiac events (P > 0.05). CONCLUSIONS: G2-DESs have better efficacy, represented by a reduced risk of TLR, and similar safety compared with BP-DESs in patients without DM. G2-DESs have similar efficacy and safety compared with BP-DESs in patients with DM at 2-year follow-up.

Effect of sex difference in clinical presentation (stable coronary artery disease vs unstable angina pectoris or non-ST-elevation myocardial infarction vs ST-elevation myocardial infarction) on 2-year outcomes in patients undergoing percutaneous coronary intervention.

OBJECTIVE: To determine whether there is a difference in 2-year prognosis among patients across the spectrum of coronary artery disease undergoing percutaneous coronary intervention (PCI). METHODS: We analyzed all consecutive patients undergoing PCI at a single center from 1/1-12/31/2013. Clinical presentations were compared between sexes according to baseline clinical, angiographic, and procedural characteristics and 2-year (mean 730 ± 30-day) outcomes. RESULTS: We grouped 10 724 consecutive patients based on sex and clinical presentation. Among patients with ST-elevation myocardial infarction (STEMI), rates of all-cause death (6.7% vs 1.4%) and cardiac death (3.8% vs 1.1%) were significantly higher in women than in men (P < 0.05), but these rates did not differ between men and women with stable coronary artery disease (SCAD) and non-ST-elevation acute coronary syndrome ((NSTE-ACS). Incidence of major bleeding was greater than in men only in those women presenting with ACS. After multivariable adjustment, female sex was not an independent predictor of outcomes in STEMI (hazard ratio [HR] for all-cause death: 1.33, 95% confidence interval [CI]:0.52-3.38; P = 0.55; HR for cardiac death: 0.69, 95%CI: 0.23-2.09, P = 0.51], but was still an independent predictor of bleeding in STEMI (HR: 3.53, 95%CI: 1.26-9.91, P = 0.017). CONCLUSION: Among STEMI patients, women had worse 2-year mortality after PCI therapy, but female sex was not an independent predictor of mortality after adjustment for baseline characteristics. In STEMI patients, women were at higher bleeding risk than men after PCI, even after multivariable adjustment.

Effect of coronary dominance on 2-year outcomes after percutaneous coronary intervention in patients with acute coronary syndrome.

OBJECTIVES: This retrospective, single-center, observational analysis from prospectively collected database evaluated whether left dominance affected the long-term outcomes of acute coronary syndrome patients undergoing percutaneous coronary intervention, and whether the effect was independent of SYNTAX score. BACKGROUND: Left dominance is believed to be associated with worse prognoses. The anatomical SYNTAX score is a scoring system based on the complexity and severity of coronary lesions and is thought to be a prognostic tool to predict short- and long-term outcomes. There are few studies about whether the effect of left dominance is independent of SYNTAX score. METHODS: Between January 2013 and December 2013, 6255 consecutive acute coronary syndrome patients who were admitted to Fuwai hospital and underwent percutaneous coronary intervention (PCI) were enrolled in this study. Based on coronary dominance and the calculation methods of the SYNTAX score, patients were divided into a left-dominant group (LD group; 390 patients) and a right-dominant or co-dominant group (RD + Co group, 5865 patients). RESULT: The 2-year mortality rate was significantly higher in the LD group than in the RD + Co group (2.58% vs. 1.23%, P = 0.024). In multivariate Cox analysis, the independent predictors of mortality were coronary dominance, IABP support, age, baseline SYNTAX score, and ejection fraction. CONCLUSIONS: LD was an independent predictor of long-term mortality in ACS patients undergoing PCI. The effect of LD still existed after adjustment for several important variables and was independent of SYNTAX score. © 2017 Wiley Periodicals, Inc.

Effect of platelet receptor gene polymorphisms on outcomes in ST-elevation myocardial infarction patients after percutaneous coronary intervention.

Polymorphisms in platelet receptor genes may influence platelet function. This study aimed to assess the impact of five polymorphisms of genes encoding platelet receptors on the risk of ischemic and bleeding events in ST-elevation myocardial infarction (STEMI) patients after percutaneous coronary intervention (PCI). 503 consecutive Chinese patients with STEMI after an uneventful PCI and exposed to standard dual antiplatelet therapy for 12 months were enrolled. Polymorphisms of platelet receptors, GPIa (ITGA2, 807C > T, rs1126643), GPVI (GP6, 13254T > C, rs1613662), PAR-1 (F2R, IVS-14A > T, rs168753) and P2Y12 (P2RY12, 34C > T, rs6785930 and H1/H2 haplotype, 52G > T, rs6809699) were detected by the ligase detection reaction. The follow-up period was 12 months. Overall, 34 (6.8%) ischemic events occurred and 46 (9.1%) major bleedings occurred. Multivariate Cox regression analysis showed the carriage of F2R rs168753 minor allele was an independent predictor of the composite ischemic events (HR 0.387, 95% CI 0.193-0.778, p = 0.008) after adjusted for established risk factors. Multivariate logistic regression model identified that carriage of P2RY12 rs6809699 minor allele (OR 2.71, 95% CI 1.298-5.659, p = 0.008) was an independent predictor of major bleedings. The associations were then validated in a second cohort of 483 STEMI patients. In STEMI patients after PCI, F2R rs168753 minor allele could significantly contribute to the risk of ischemic events, and P2RY12 rs6809699 minor allele could predict bleedings. The genetic testing of platelet receptors can be valuable in predicting adverse events in STEMI patients after PCI.

Harpertrioate A, an A,B,D-seco-Limonoid with Promising Biological Activity against Alzheimer's Disease from Twigs of Harrisonia perforata (Blanco) Merr.

Harpertrioate A (1), an A,B,D-seco-limonoid with a rearranged ring B incorporating exocyclic C-30, was isolated from the EtOAc extract of Harrisonia perforata twigs. Its structure, including absolute configurations, was determined on the basis of spectroscopic data and X-ray crystallography. This compound exhibited biological activities against Alzheimer's disease by reducing Aß42 and Aß40 production and shifting APP processing toward nonamyloidogenic pathway. The effect of 1 on the Aß production was comparable to that of gemfibrozil.

12ß-Acetyloxyperforatin, a New Limonoid from Harrisonia Perforata.

A new A, D-seco limonoid, named 12-acetyloxyperforatin (1), along with three known ones, were isolated from the leaves of Harrisonia perforata. Their structures were elucidated on the basis of spectroscopic analysis, including extensive NMR techniques and computational modelling. These compounds showed no inhibitory activity against the 11ß-HSD1 enzyme.

Abietane Diterpernoids from the Roots of Euphorbia ebracteolata.

A new ent-abietane diterpernoid, named ebracteolata D (1), along with 11 known analogues, was isolated from the roots of Euphorbia ebracteolata Hayata. The structure of 1 was elucidated on the basis of spectroscopic analysis and molecular modeling. Cytotoxicity of compounds 1-12 was evaluated as well as the effect on the NF-κB pathway. Among them, compound 12, jolkinolide B, displayed broad inhibitory effects against proliferation of tumor cell lines. Mechanistic studies indicated that the compound 12 can inhibit TNF-α induced NF-κB activation, thereby inducing tumor cell apoptosis.

Comparison of Efficacy and Safety between First- and Second-Generation Drug-Eluting Stents in Patients with Acute Coronary Syndrome.

BACKGROUND: It remains undetermined whether second-generation drug-eluting stents (G2-DESs) outperform first-generation DESs (G1-DESs) in patients with acute coronary syndrome (ACS). We aimed to compare the efficacy and safety of G1-DES and G2-DES in ACS patients in a high-volume cardiovascular center. METHODS: In 2013, 10,724 consecutive patients underwent percutaneous coronary intervention in our institution. We included 4037 patients with ACS who underwent exclusively G1-DES or G2-DES implantation (n = 364 and n = 3673, respectively). We used propensity score matching to minimize the imbalance between the G1-DES and G2-DES groups and followed patients for 2 years. The efficacy endpoints were major adverse cardiac events (MACEs) and its components including target vessel-related myocardial infarction (TV-MI), target vessel revascularization/target lesion revascularization (TVR/TLR), and cardiac death. The safety endpoint was stent thrombosis. Continuous variables were compared by Mann-Whitney U-test, and categorical variables were compared using Pearson's Chi-square or Fisher's exact test. Kaplan-Meier curves were constructed to compare the event-free survival rates, and multivariate Cox proportional hazards regression analysis was used to assess whether stent type was an independent risk factor for the efficacy and safety endpoints. RESULTS: At the 2-year follow-up, the results for MACE and it components, as well as stent thrombosis, were similar for G1-DES and G2-DES (MACE, 5.2% vs. 4.3%, χ2 = 0.514, P = 0.474; TV-MI, 0.8% vs. 0.4%, P = 0.407; TVR, 4.9% vs. 3.7%, χ2 = 0.939, P = 0.333; TLR, 3.8% vs. 2.5%, χ2 = 1.610, P = 0.205; cardiac death, 0.3% vs. 0.5%, P = 0.670; and stent thrombosis, 0.5% vs. 0.4%, P > 0.999). Kaplan-Meier analysis indicated similar event-free survival rates between G1-DES and G2-DES after propensity score matching (all: log-rank P > 0.05). Multivariate analysis demonstrated that stent type was not an independent risk factor for the efficacy and safety endpoints (MACE, hazard ratio [HR] = 0.805, 95% confidence interval [CI]: 0.455-1.424, P = 0.456; TV-MI, HR = 0.500, 95% CI: 0.101-2.475, P = 0.395; TVR, HR = 0.732, 95% CI: 0.403-1.330, P = 0.306; TLR, HR = 0.629, 95% CI: 0.313-1.264, P = 0.193; cardiac death, HR = 1.991, 95% CI: 0.223-17.814, P = 0.538; and stent thrombosis, HR = 0.746, 95% CI: 0.125-4.467, P = 0.749). CONCLUSION: G1-DES and G2-DES have similar efficacy and safety profiles in ACS patients at the 2-year follow-up.

Comparison of Efficacy and Safety between First and Second Generation Drug-eluting Stents in Patients with Stable Coronary Artery Disease: A Single-center Retrospective Study.

BACKGROUND: Lots of trials demonstrate that second-generation drug-eluting stents (G2-DES), with their improved properties, offer significantly superior efficacy and safety profiles compared to first generation DES (G1-DES) for patients with coronary artery disease (CAD) receiving percutaneous coronary intervention (PCI). This study aimed to verify the advantage of G2-DES over G1-DES in Chinese patients with stable CAD (SCAD). METHODS: For this retrospective observational analysis, 2709 SCAD patients with either G1-DES (n = 863) or G2-DES (n = 1846) were enrolled consecutively throughout 2013. Propensity score matching (PSM) was applied to control differing baseline factors. Two-year outcomes, including major adverse coronary events as well as individual events, including target vessel-related myocardial infarction, target lesion revascularization (TLR), target vessel revascularization, and cardiogenic death were evaluated. RESULTS: The incidence of revascularization between G1- and G2-DES showed a trend of significant difference with a threshold P - value (8.6% vs. 6.7%, χ2 = 2.995, P = 0.084). G2-DES significantly improved TLR-free survival compared to G1-DES (96.6% vs. 97.9%, P = 0.049) and revascularization-free survival curve showed a trend of improvement of G2-DES (92.0% vs. 93.8%, P = 0.082). These differences diminished after PSM. Multivariate Cox proportional hazard regression analysis showed a trend for G1-associated increase in revascularization (hazard ratio: 1.28, 95% confidence interval: 0.95-1.72, P = 0.099) while no significance was found after PSM. Other endpoints showed no significant differences after multivariate adjustment regardless of PSM. CONCLUSIONS: G1-DES showed the same safety as G2-DES in this large Chinese cohort of real-world patients. However, G2-DES improved TLR-free survival of SCAD patients 2 years after PCI. The advantage was influenced by baseline clinical factors. G1-DES was associated with a trend of increase in revascularization risk and was not an independent predictor of worse medium-term prognosis compared with G2-DES.

Long-term Outcomes of Primary Percutaneous Coronary Intervention with Second-generation Drug-eluting Stents in ST-elevation Myocardial Infarction Patients Caused by Very Late Stent Thrombosis.

BACKGROUND: The ST-segment elevation myocardial infarction (STEMI) patients due to stent thrombosis (ST) remain a therapeutic challenge for a clinician. Till date, very few researches have been conducted regarding the safety and effectiveness of primary percutaneous coronary intervention (PCI) with second-generation drug-eluting stents (DES) for STEMI caused by very late ST (VLST). This retrospective study evaluated the safety, efficacy, and outcomes of primary PCI with second-generation DES for STEMI due to VLST compared with primary PCI for STEMI due to de novo lesion. METHODS: Between January 2007 and December 2013, STEMI patients with primary PCI in Fuwai Hospital had only second-generation DES implanted for de novo lesion (558 patients) and VLST (50 patients) were included in this retrospective study. The primary end points included cardiac death and reinfarction. The secondary end points included cardiac death, reinfarction, and target lesion revascularization. Continuous variables were expressed as mean (standard deviation) or median (interquartile range) and compared by Student's t- test or Mann-Whitney U-test as appropriate. Categorical variables were expressed as counts and percentages, and comparison of these variables was performed with Chi-square or Fisher's exact test. A two-tailed value of P < 0.05 was considered statistically significant for all comparisons. Statistical analyses were performed by SAS software (version 9.4, SAS Institute Inc., Cary, USA) for Windows. RESULTS: In-hospital primary end point and the secondary end point were no significant differences between two groups (P = 1.000 and P = 1.000, respectively). No significant differences between two groups were observed according to the long-term primary end point and the secondary end point. Kaplan-Meier survival curves showed no significant difference between the two groups in the primary end point and the secondary end point at 2 years (P = 0.340 and P = 0.243, respectively). According to Cox analysis, female, intra-aortic balloon pump support, and postprocedural thrombolysis in myocardial infarction flow 3 were found to be independent predictors for long-term follow-up. CONCLUSION: Primary PCI with second-generation DES is a reasonable choice for STEMI patients caused by VLST.

Head to Head Comparison of Two Point-of-care Platelet Function Tests Used for Assessment of On-clopidogrel Platelet Reactivity in Chinese Acute Myocardial Infarction Patients Undergoing Percutaneous Coronary Intervention.

BACKGROUND: Platelet function tests are widely used in clinical practice to guide personalized antiplatelet therapy. In China, the thromboelastography (TEG) test has been well accepted in clinics, whereas VerifyNow, mainly used for scientific research, has not been used in routine clinical practice. The aim of the current study was to compare these two point-of-care platelet function tests and to analyze the consistency between the two tests for evaluating on-clopidogrel platelet reactivity in Chinese acute myocardial infarction patients undergoing percutaneous coronary intervention (PCI). METHODS: A total of 184 patients admitted to Fuwai Hospital between August 2014 and May 2015 were enrolled in the study. On-clopidogrel platelet reactivity was assessed 3 days after PCI by TEG and VerifyNow using adenosine diphosphate as an agonist. Based on the previous reports, an inhibition of platelet aggregation (IPA) <30% for TEG or a P2Y12 reaction unit (PRU) >230 for VerifyNow was defined as high on-clopidogrel platelet reactivity (HPR). An IPA >70% or a PRU <178 was defined as low on-clopidogrel platelet reactivity (LPR). Correlation and agreement between the two methods were analyzed using the Spearman correlation coefficient (r) and kappa value (κ), respectively. RESULTS: Our results showed that VerifyNow and TEG had a moderate but significant correlation in evaluating platelet reactivity (r = -0.511). A significant although poor agreement (κ = 0.225) in identifying HPR and a significantly moderate agreement in identifying LPR (κ = 0.412) were observed between TEG and VerifyNow. By using TEG as the reference for comparison, the cutoff values of VerifyNow for the Chinese patients in this study were identified as PRU >205 for HPR and PRU <169 for LPR. CONCLUSIONS: By comparing VerifyNow to TEG which has been widely used in clinics, VerifyNow could be an attractive alternative to TEG for monitoring on-clopidogrel platelet reactivity in Chinese patients.

Association of PEAR1 genetic variants with platelet reactivity in response to dual antiplatelet therapy with aspirin and clopidogrel in the Chinese patient population after percutaneous coronary intervention.

INTRODUCTION: Platelet Endothelial Aggregation Receptor-1 (PEAR1) is a recently reported platelet transmembrane protein which plays an important role in platelet aggregation. The aim of this study was to investigate whether PEAR1 genetic variations were associated with platelet reactivity as assessed by adenosine diphosphate(ADP)-induced platelet aggregation in Chinese patients treated with aspirin and clopidogrel. METHODS: Patients with coronary heart disease (CHD) who underwent percutaneous coronary intervention (PCI) were enrolled in the study. All patients were on dual antiplatelet therapy with aspirin and clopidogrel. ADP-induced platelet aggregation was measured by thromboelastography and defined as percent inhibition of platelet aggregation (IPA). Patients (n=204) with IPA <30% were identified as high on-treatment platelet reactivity (HPR). Patients (n=201) with IPA >70% were identified as low on-treatment platelet reactivity (LPR). Sixteen single nucleotide polymorphisms (SNPs) of PEAR1 were determined by a method of improved multiple ligase detection reaction. RESULTS: Among the 16 SNPs examined by univariate analysis, 5 SNPs were significantly associated with ADP-induced platelet aggregation. Minor allele C at rs11264580 (p=0.033), minor allele G at rs2644592 (p=0.048), minor allele T at rs3737224 (p=0.033) and minor allele T at rs41273215 (p=0.025) were strongly associated with HPR, whereas homozygous TT genotype at rs57731889 (p=0.009) was associated with LPR. Multivariate logistic regression analysis further revealed that the minor allele T at rs41273215 (p=0.038) was an independent predictor of HPR and the homozygous TT genotype at rs57731889 (p=0.003) was an independent predictor of LPR. CONCLUSIONS: PEAR1 genetic variations were strongly associated with ADP-induced platelet aggregation in Chinese patients with CHD treated with aspirin and clopidogrel. These genetic variations may contribute to the variability in platelet function. The utility of PEAR1 genetic variants in the assessment and prediction of cardiovascular risk warrants further investigation.

Palladium-catalyzed unactivated C(sp3)-H bond activation and intramolecular amination of carboxamides: a new approach to ß-lactams.

An efficient method to synthesize the ß-lactams with high regioselectivity via Pd-catalyzed C(sp(3))-H bond activation and intramolecular amination of simple and readily available aminoquinoline carboxamides was demonstrated. C6F5I plays a significant role in the formation of the C-N bond of the four-membered ring ß-lactams. High yield along with wide substrate scope and functional group tolerance makes this reaction applicable to build natural-product-derived ß-lactams. This method has been applied to the efficient synthesis of the ß-lactamase inhibitor MK-8712.

Cascade N-Alkylation/Hemiacetalization for Facile Construction of the Spiroketal Skeleton of Acortatarin Alkaloids with Therapeutic Potentiality in Diabetic Nephropathy.

The concise building of the spiroketal core of acortatarin-type alkaloids as potential therapeutic agents in diabetic nephropathy was established in four steps, through a tandem N-alkylation/hemiacetalization between pyrrole units and the corresponding halo alcohols generated by convenient halomethylation of chiral lactones from natural aldoses.

Relationship between ABCB1 polymorphisms, thromboelastography and risk of bleeding events in clopidogrel-treated patients with ST-elevation myocardial infarction.

INTRODUCTION: This study sought to investigate the relationship of polymorphisms in ABCB1 and the predictive value of thromboelastography (TEG) on bleeding risk in clopidogrel-treated patients with ST-elevation myocardial infarction (STEMI). METHODS: 467 consecutive patients with STEMI undergoing percutaneous coronary intervention (PCI) were enrolled. Twenty tag single nucleotide polymorphisms (SNPs) selected from ABCB1 gene and CYP2C19*2, *3, *17 were detected by the ligase detection reaction. Platelet reactivity was assessed by TEG. The follow-up period was 12months. RESULTS: By receiver operating characteristic curve analysis, the TEG platelet mapping assay value of ADP inhibition had the best predictive value of bleeding academic research consortium definition (BARC) ≥ 3b bleedings, yielding an area under the curve (AUC) of 0.707 (95% CI 0.662-0.749, p=0.009; cut-off value > 93.4%). ADP inhibition can also predict BARC ≥ 3 bleedings with an AUC of 0.594 (95% CI 0.546-0.640, p = 0.05; cut-off value > 92.5%). After adjustment for established risk factors of bleeding including the gain of function CYP2C19*17 allele, age, female gender, renal function, the multivariable logistic regression model demonstrated that ADP inhibition > 92.5% (OR 2.247, 95%CI 1.082-4.665, P=0.03), carriage of rs1045642 (OR 2.943, 95%CI 1.195-7.247, P = 0.019) and rs7779562 (OR 0.453, 95%CI 0.219-0.936, P = 0.032) were independent predictors of BARC ≥ 3 bleedings. These associations were validated in a second cohort of 504 STEMI patients. CONCLUSIONS: In STEMI patients treated with clopidogrel after PCI, the ABCB1 tag SNP rs1045642 is associated with higher risk of bleedings while rs7779562 is associated with lower bleeding risk, and ADP inhibition in TEG has a predictive value of bleedings.