Drug-coated balloon for the treatment of small vessel disease: 9 months of angiographic results and 12 months of clinical outcomes of the PEPCAD China SVD study.

BACKGROUND: Whether the drug-coated balloons (DCBs)-alone strategy was superior to plain old balloon angioplasty (POBA) in treating SVD remains unknown. AIMS: We aimed to evaluate the efficacy and safety of DCBs for the treatment of coronary de novo small vessel disease (SVD) and provide further evidence for extending the clinical indications of DCBs. (ChiCTR1800014966). METHODS: Eligible patients were randomized at a 2:1 ratio to receive DCB treatment or POBA in this prospective, multicenter clinical trial. The reference vessel diameter of lesions was visually assessed to be 2.0 to 2.75 mm. The primary endpoint of the study was angiographic in-segment late luminal loss (LLL) at the 9-month follow-up to demonstrate the superiority of DCB treatment to POBA in SVD. The composite clinical endpoints included clinically driven target lesion revascularization (CD-TLR), target lesion failure (TLF), major adverse cardiac events (MACEs), and thrombosis at the 12-month follow-up. RESULTS: A total of 270 patients were enrolled (181 for DCB, 89 for POBA) at 18 centers in China. The primary endpoint of 9-month in-segment LLL in the intention-to-treat population was 0.10 ± 0.33 mm with DCB and 0.25 ± 0.38 mm with POBA (p = 0.0027). This difference indicated significant superiority of DCB treatment (95% CI: -0.22, -0.04, psuperiority = 0.0068). The rates of the clinical endpoints-CD-TLR, TLF, and MACEs-were comparable between groups. No thrombosis events were reported. CONCLUSIONS: DCB treatment of de novo SVD was superior to POBA with lower 9-month in-segment LLL. The rates of clinical events were comparable between the two devices.

Dynamic perfusion SPECT for functional evaluation in symptomatic patients with myocardial bridging.

BACKGROUND: The aim of this study was to investigate the feasibility and diagnostic value of myocardial flow reserve (MFR) assessed by rest/stress myocardial perfusion imaging with dynamic single-photon emission computed tomography (SPECT) in the functional evaluation of myocardial bridge (MB). METHODS: From May 2017 to July 2021, patients with angiographically confirmed isolated MB on the left anterior descending artery (LAD) who underwent dynamic SPECT myocardial perfusion imaging were retrospectively included. The assessment of semiquantitative indices of myocardial perfusion (summed stress scores, SSS) and quantitative parameters (MFR) was performed. RESULTS: A total of 49 patients were enrolled. The mean age of the subjects was 61.0 ± 9.0 years. All of the patients were symptomatic, and 16 cases (32.7%) presented with typical angina. SPECT-derived MFR showed a borderline significantly negative correlation with SSS (r = 0.261, P = .070). There was a trend of higher prevalence of impaired myocardial perfusion defined as MFR < 2 than as SSS ≥ 4 (42.9% vs 26.5%; P = .090). CONCLUSION: Our data support that SPECT MFR may be a useful parameter for the functional assessment of MB. In patients with MB, the use of dynamic SPECT could be a potential method for hemodynamic assessment.

The current scenario on anticancer activity of artemisinin metal complexes, hybrids, and dimers.

Cancer, the most significant cause of morbidity and mortality, has already posed a heavy burden on health care systems globally. In recent years, cancer treatment has made a significant breakthrough, but cancer cells inevitably acquire resistance, and the efficacy of the treatment is greatly reduced as the tumor progresses. To overcome the above issues, novel chemotherapeutics are needed urgently. Artemisinin and its derivatives-sesquiterpene lactone compounds possessing a unique peroxy bridge moiety-exhibit excellent safety and tolerability profiles. Mechanistically, artemisinin derivatives can promote cancer cell apoptosis, induce cell cycle arrest and autophagy, and inhibit cancer cell invasion and migration. Accordingly, artemisinin derivatives demonstrate promising anticancer efficacy both in vitro and in vivo, and even in clinical Phase I/II trials. The purpose of the present review article is to provide an emphasis on the current scenario (January 2017-January 2022) of artemisinin derivatives with potential anticancer activity, inclusive of artemisinin metal complexes, hybrids, and dimers. The structure-activity relationships and mechanisms of action are also discussed to facilitate the further rational design of more effective candidates.

Chemical Proteomic Profiling of Bromodomains Enables the Wide-Spectrum Evaluation of Bromodomain Inhibitors in Living Cells.

Bromodomains, epigenetic "readers" of lysine acetylation marks, exist in different nuclear proteins with diverse biological functions in chromatin biology. Malfunctions of bromodomains are associated with the pathogenesis of human diseases, such as cancer. Bromodomains have therefore emerged as therapeutic targets for drug discovery. Given the high structural similarity of bromodomains, a critical step in the development of bromodomain inhibitors is the evaluation of their selectivity to avoid off-target effects. While numerous bromodomain inhibitors have been identified, new methods to evaluate the inhibitor selectivity toward endogenous bromodomains in living cells remain needed. Here we report the development of a photoaffinity probe, photo-bromosporine (photo-BS), that enables the wide-spectrum profiling of bromodomain inhibitors in living cells. Photo-BS allowed light-induced cross-linking of recombinant bromodomains and endogenous bromodomain-containing proteins (BCPs) both in vitro and in living cells. The photo-BS-induced labeling of the bromodomains was selectively competed by the corresponding bromodomain inhibitors. Proteomics analysis revealed that photo-BS captured 28 out of the 42 known BCPs from the living cells. Assessment of the two bromodomain inhibitors, bromosporine and GSK6853, resulted in the identification of known as well as previously uncharacterized bromodomain targets. Collectively, we established a chemical proteomics platform to comprehensively evaluate bromodomain inhibitors in terms of their selectivity against endogenous BCPs in living cells.

Role of KCa3.1 Channels in Macrophage Polarization and Its Relevance in Atherosclerotic Plaque Instability.

OBJECTIVE: Emerging evidence indicates that proinflammatory macrophage polarization imbalance plays a key role in atherosclerotic plaque progression and instability. The calcium-activated potassium channel KCa3.1 is critically involved in macrophage activation and function. However, the role of KCa3.1 in macrophage polarization is unknown. This study investigates the potential role of KCa3.1 in transcriptional regulation in macrophage polarization and its relationship to plaque instability. APPROACH AND RESULTS: Human monocytes were differentiated into macrophages using macrophage colony-stimulating factor. Macrophages were then polarized into proinflammatory M1 cells by interferon-γ and lipopolysaccharide and into alternative M2 macrophages by interleukin-4. A model for plaque instability was induced by combined partial ligation of the left renal artery and left common carotid artery in apolipoprotein E knockout mice. Significant upregulation of KCa3.1 expression was observed during the differentiation of human monocytes into macrophages. Blocking KCa3.1 significantly reduced the expression of proinflammatory genes during macrophages polarization. Further mechanistic studies indicated that blocking KCa3.1 inhibited macrophage differentiation toward the M1 phenotype by downregulating signal transducer and activator of transcription-1 phosphorylation. In animal models, KCa3.1 blockade therapy strikingly reduced the incidence of plaque rupture and luminal thrombus in carotid arteries, decreased the expression of markers associated with M1 macrophage polarization, and enhanced the expression of M2 markers within atherosclerotic lesions. CONCLUSIONS: These results suggest that blocking KCa3.1 suppresses plaque instability in advanced stages of atherosclerosis by inhibiting macrophage polarization toward an M1 phenotype.

Design, synthesis, and molecular docking study of 3H-imidazole[4,5-c]pyridine derivatives as CDK2 inhibitors.

A novel series of imidazo[4,5-c]pyridine-based CDK2 inhibitors were designed from the structure of CYC202 via scaffold hopping strategy. These compounds were synthesized and biologically evaluated for their CDK2 inhibitory and in vitro anti-proliferation potential against cancer cell lines. Several compounds exhibited potent CDK2 inhibition with IC50 values of less than 1 µM. The most potent compound 5b showed excellent CDK2 inhibitory (IC50 = 21 nM) and in vitro anti-proliferation activity against three different cell lines (HL60, A549, and HCT116). The molecular docking and dynamic studies portrayed the potential binding mechanism between 5b and CDK2, and several key interactions between them were observed, which would be the reason for its potent CDK2 inhibitory and anti-proliferation activities. Therefore, the pyridin-3-ylmethyl moiety would serve as an excellent pharmacophore for the development of novel CDK2 inhibitors for targeted anti-cancer therapy.

High glucose instigates tubulointerstitial injury by stimulating hetero-dimerization of adiponectin and angiotensin II receptors.

Abnormal expression and dysfunction of adiponectin and the cognate receptors are involved in diabetes and diabetic kidney disease (DKD), whereas angiotensin receptor blockers (ARBs) and angiotensin-converting enzyme inhibitors (ACEIs) alleviate diabetic albuminuria and prevent development of DKD through upregulation of adiponectin expression. Here we report that high glucose stimulates expression of angiotensin II (AngII) receptors (AT1 and AT2) in renal proximal tubular epithelial cells (NRK-52E). These receptors underwent hetero-dimerization with adiponectin receptor AdipoR1 and AdipoR2, respectively. High glucose inhibited the dimerization between AT1 and AT2. Interestingly, these hetero-dimers instigated tubulointerstitial injury by inhibiting the cytoprotective action of the adiponectin receptors. These modes of receptor-receptor hetero-dimerization may contribute to high glucose-induced renal tubulointerstitial injury and could be potential therapeutic targets.

Six-month outcomes of the XINSORB bioresorbable sirolimus-eluting scaffold in treating single de novo lesions in human coronary artery.

OBJECTIVE: We aimed to investigate short-term outcomes of the XINSORB bioresorbable sirolimus-eluting scaffold in human coronary artery. BACKGROUND: Bioresorbable scaffolds are considered to be the fourth milestone in percutaneous coronary intervention. METHODS: Thirty patients with symptomatic ischemic coronary disease were enrolled and treated with the XINSORB scaffolds that were 3.0 × 12, 15, and 18 mm in size. The primary angiographic endpoint was late luminal loss (LLL), whereas the primary clinical endpoint was major adverse cardiac events (MACEs) at the 6 month follow-up. In a subset of 19 patients, intravascular ultrasound (IVUS) and optical coherence tomography (OCT) were performed at follow-up. RESULTS: The success rates of the procedure and the device were both 100%. Twenty-seven patients received angiographic follow-up. All patients were clinically assessed. Neither MACEs nor stent thrombus-related events were recorded. The percentage of diameter stenosis at follow-up was similar to that at postprocedure. In-scaffold and periscaffold LLL were 0.17 ± 0.12 and 0.13 ± 0.24 mm, respectively. No in-stent restenosis was detected. IVUS showed that the mean areas of the lumen, scaffold, and neointima at follow-up were 6.27 ± 0.69, 6.48 ± 0.70, and 0.20 ± 0.09 mm(2) , while in-device stenosis was 3.1 ± 1.3%. OCT showed that 97.9% of the struts presented a preserved box, while 2.1% had an open box after 6 months. A total of 95.9% of the struts were covered by neointima. CONCLUSIONS: This first-in-human study demonstrates the effectiveness and safety of the XINSORB scaffold in treating single de novo coronary lesions.

MYT1L deficiency impairs excitatory neuron trajectory during cortical development.

Mutations that reduce the function of MYT1L, a neuron-specific transcription factor, are associated with a syndromic neurodevelopmental disorder. Furthermore, MYT1L is routinely used as a proneural factor in fibroblast-to-neuron transdifferentiation. MYT1L has been hypothesized to play a role in the trajectory of neuronal specification and subtype specific maturation, but this hypothesis has not been directly tested, nor is it clear which neuron types are most impacted by MYT1L loss. In this study, we profiled 313,335 nuclei from the forebrains of wild-type and MYT1L-deficient mice at two developmental stages: E14 at the peak of neurogenesis and P21, when neurogenesis is complete, to examine the role of MYT1L levels in the trajectory of neuronal development. We found that MYT1L deficiency significantly disrupted the relative proportion of cortical excitatory neurons at E14 and P21. Significant changes in gene expression were largely concentrated in excitatory neurons, suggesting that transcriptional effects of MYT1L deficiency are largely due to disruption of neuronal maturation programs. Most effects on gene expression were cell autonomous and persistent through development. In addition, while MYT1L can both activate and repress gene expression, the repressive effects were most sensitive to haploinsufficiency, and thus more likely mediate MYT1L syndrome. These findings illuminate the intricate role of MYT1L in orchestrating gene expression dynamics during neuronal development, providing insights into the molecular underpinnings of MYT1L syndrome.

MECP2 directly interacts with RNA polymerase II to modulate transcription in human neurons.

Mutations in the methyl-DNA-binding protein MECP2 cause the neurodevelopmental disorder Rett syndrome (RTT). How MECP2 contributes to transcriptional regulation in normal and disease states is unresolved; it has been reported to be an activator and a repressor. We describe here the first integrated CUT&Tag, transcriptome, and proteome analyses using human neurons with wild-type (WT) and mutant MECP2 molecules. MECP2 occupies CpG-rich promoter-proximal regions in over four thousand genes in human neurons, including a plethora of autism risk genes, together with RNA polymerase II (RNA Pol II). MECP2 directly interacts with RNA Pol II, and genes occupied by both proteins showed reduced expression in neurons with MECP2 patient mutations. We conclude that MECP2 acts as a positive cofactor for RNA Pol II gene expression at many neuronal genes that harbor CpG islands in promoter-proximal regions and that RTT is due, in part, to the loss of gene activity of these genes in neurons.

A novel intracoronary hypothermia device reduces myocardial reperfusion injury in pigs.

BACKGROUND: Hypothermia therapy has been suggested to attenuate myocardial necrosis; however, the clinical implementation as a valid therapeutic strategy has failed, and new approaches are needed to translate into clinical applications. This study aimed to assess the feasibility, safety, and efficacy of a novel selective intracoronary hypothermia (SICH) device in mitigating myocardial reperfusion injury. METHODS: This study comprised two phases. The first phase of the SICH was performed in a normal porcine model for 30 minutes ( n = 5) to evaluate its feasibility. The second phase was conducted in a porcine myocardial infarction (MI) model of myocardial ischemia/reperfusion was performed by balloon occlusion of the left anterior descending coronary artery for 60 minutes and maintained for 42 days. Pigs in the hypothermia group ( n = 8) received hypothermia intervention onset reperfusion for 30 minutes and controls ( n = 8) received no intervention. All animals were followed for 42 days. Cardiac magnetic resonance analysis (5 and 42 days post-MI) and a series of biomarkers/histological studies were performed. RESULTS: The average time to lower temperatures to a steady state was 4.8 ± 0.8 s. SICH had no impact on blood pressure or heart rate and was safely performed without complications by using a 3.9 F catheter. Interleukin-6 (IL-6), tumor necrosis factor-α, C-reactive protein (CRP), and brain natriuretic peptide (BNP) were lower at 60 min post perfusion in pigs that underwent SICH as compared with the control group. On day 5 post MI/R, edema, intramyocardial hemorrhage, and microvascular obstruction were reduced in the hypothermia group. On day 42 post MI/R, the infarct size, IL-6, CRP, BNP, and matrix metalloproteinase-9 were reduced, and the ejection fraction was improved in pigs that underwent SICH. CONCLUSIONS: The SICH device safely and effectively reduced the infarct size and improved heart function in a pig model of MI/R. These beneficial effects indicate the clinical potential of SICH for treatment of myocardial reperfusion injury.

Validation of a new non-hyperemic physiological index: the constant-resistance ratio (cRR).

OBJECTIVES: The instantaneous wave-free ratio (iwFR) has limited availability. A new resting index called the constant-resistance ratio (cRR), which dynamically identifies cardiac intervals with constant and minimum resistance, has been developed; however, its diagnostic performance is unknown. The aim of this study was to validate the cRR by retrospectively calculating the cRR values from raw pressure waveforms of 2 publicly available datasets and compare them with those of the iwFR. METHODS: Waveform data from the CONTRAST and VERIFY 2 studies were used. The primary endpoint was Bland-Altman bias between cRR and iwFR. Secondary endpoints included diagnostic agreement, correlation, receiver operating characteristic (ROC) analysis, and success rates of cRR and iwFR. RESULTS: Among the 1036 waveforms, 871 were successful in determining paired cRR and iwFR values, while cRR was 6% more successful than iwFR (P less than .0001). The mean bias between cRR and iwFR was 0.003, with 95% limits of agreement [-0.021,0.028]. These 2 indices were highly correlated (r = 0.991; P less than .0001). Using an iwFR of 0.89 or less as the reference standard, the optimal cRR cutoff was 0.89, with an area under the ROC curve of 0.991 (P less than .001) and a diagnostic accuracy of 96.9% (95% CI [96%, 98%]). CONCLUSIONS: The cRR, a new resting index for identifying dynamic cardiac intervals with constant and minimum resistance, demonstrated high numerical agreement, diagnostic consistency, and a higher success rate than the iwFR based on the 2 publicly available datasets.

The standard versus prolonged dual antiplatelet therapy after the XINSORB bioresorbable scaffold implantation (SPARTA) trial: study protocol for a randomized controlled trial.

BACKGROUND: Dual antiplatelet therapy (DAPT) with aspirin and a P2Y12 inhibitor is the standard of care after coronary stenting, including coronary stenting involving bioresorbable scaffolds (BRSs). Current clinical guidelines recommend at least 12 months of DAPT after BRS implantation. However, the correlation between prolonged DAPT and net clinical benefits remains unknown. METHODS: The SPARTA trial is designed to be a prospective, randomized, parallel-group, clinical trial. It aims to compare the benefits and risks of DAPT applied for either 12 or 36 months after XINSORB BRS implantation. The primary endpoints are the incidence of the composite endpoint of major adverse cardiac events (MACEs), including all-cause death, any myocardial infarction (MI), and all revascularizations, as well as Bleeding Academic Research Consortium Definition (BARC) type 3 or 5 bleeding events. The secondary endpoints of the study include the device-oriented composite endpoint of target lesion failure (defined as cardiac death, target vessel-related MI, or ischemia-driven target lesion revascularization), target vessel failure (defined as cardiac death, MI, or ischemia-driven target vessel revascularization), scaffold thrombosis, and minor bleeding events. This trial will enroll 2106 subjects treated with the XINSORB BRS only. All subjects will receive DAPT after the index procedure for 12 (± 1) months. Subjects without MACEs or major bleeding will be randomized to receive either 24 additional months of DAPT or aspirin alone. DISCUSSION: This trial is designed to investigate the impact of extending the duration of DAPT up to 3 years after XINSORB BRS implantation by investigating the balance of risks and benefits in a broad population of treated patients. TRIAL REGISTRATION: ClinicalTrials.gov NCT04501900 . Registered on 6 August 2020.

Current development of pyrazole-azole hybrids with anticancer potential.

Chemotherapy is a critical treatment modality for cancer patients, but multidrug resistance remains one of the major challenges in cancer therapy, creating an urgent need for the development of novel potent chemical entities. Azoles, particularly pyrazole, could interact with different biological targets and exhibit diverse biological properties including anticancer activity. Many clinically used anticancer agents own an azole moiety, demonstrating that azoles are privileged and pivotal templates in the discovery of novel anticancer chemotherapeutics. The present article is an attempt to highlight the recent advances in pyrazole-azole hybrids with anticancer potential and discuss the structure-activity relationships, covering articles published from 2018 to present, to facilitate the rational design of more effective anticancer candidates.

The Association Between Angiographically Derived Radial Wall Strain and the Risk of Acute Myocardial Infarction.

BACKGROUND: The radial wall strain (RWS) is a novel angiography-based method to assess the biomechanical property of the coronary artery and whether it can predict future acute myocardial infarction (AMI) events remains to be elucidated. OBJECTIVES: This study aimed to investigate the association between angiography-derived RWS and future AMI events in mild to intermediate lesions. METHODS: We performed a matched case-control analysis nested in a retrospective cohort of patients who had received prior angiography (the index procedure) at least 1 month before and were hospitalized again for repeat angiography. Patients with at least 1 de novo mild to intermediate lesion identified at the index procedure and eligible for RWS analysis were enrolled. The study identified cases with target lesion-related AMI diagnosed at the repeat angiography, matching each case to 3 control subjects without AMI. RESULTS: Altogether 44 patients with lesion-related AMI and 132 matched controls were enrolled. The median diameter stenosis of the overall interrogated lesions was 34.0%. The baseline maximum RWS (RWSmax), which was defined as the highest RWS in the stenotic segment, was significantly higher in lesions responsible for AMI than those that remained quiescent (median 13% vs 10%; P < 0.001). RWSmax was predictive of lesion-related AMI, with an area under the curve of 0.83 (95% CI: 0.76-0.90; P < 0.001) and an optimal cutoff >12%. RWSmax >12% was found to be independently associated with subsequent AMI events with a risk ratio of 7.25 (95% CI: 3.94-13.37; P < 0.001). CONCLUSIONS: Among angiographically mild to intermediate lesions, a high-strain pattern identified by angiography-derived RWS was associated with an increased risk of AMI events.

A TEMPOL and rapamycin loaded nanofiber-covered stent favors endothelialization and mitigates neointimal hyperplasia and local inflammation.

An increased level of reactive oxygen species (ROS) plays a major role in endothelial dysfunction and vascular smooth muscle cell (VSMC) proliferation during in-stent thrombosis and restenosis after coronary artery stenting. Herein, we report an electrospun core-shell nanofiber coloaded with 4-hydroxy-2,2,6,6-tetramethylpiperidine 1-oxyl (TEMPOL) and rapamycin (RAPA) that correspondingly serves as an ROS scavenger and VSMC inhibitor. This system has the potential to improve the biocompatibility of current drug-eluting stent (DES) coatings with the long-term and continuous release of TEMPOL and rapamycin. Moreover, the RAPA/TEMPOL-loaded membrane selectively inhibited the proliferation of VSMCs while sparing endothelial cells (ECs). This membrane demonstrated superior ROS-scavenging, anti-inflammatory and antithrombogenic effects in ECs. In addition, the membrane could maintain the contractile phenotype and mitigate platelet-derived growth factor BB (PDGF-BB)-induced proliferation of VSMCs. In vivo results further revealed that the RAPA/TEMPOL-loaded covered stents promoted rapid restoration of vascular endothelium compared with DES and persistently impeded inflammation and neointimal hyperplasia in porcine models.

Are baseline conditions of coronary arteries sufficient for calculating angio-based index of microcirculatory resistance and fractional flow reserve?

Background: Angio-based index of microcirculatory resistance (IMR) and fractional flow reserve (FFR) have been developed, however, the differences between baseline and hyperemic data and their effects on their computation have not yet been discussed. This study aimed to compare the diagnostic performance of a novel method for calculating IMR and FFR from coronary angiography under baseline and hyperemic conditions. Methods: We performed a retrospective study to investigate the diagnostic performance of angiography-derived IMR (AccuIMR) and FFR (AccuFFRangio) computed from the hyperemic condition (AccuIMRhyp, AccuFFRangiohyp) and baseline condition (AccuIMRbase, AccuFFRangiobase) in 101 consecutive patients with chronic coronary syndrome (CCS) who underwent measurements of IMR and FFR at a single center, using wire-based IMR and FFR as the reference standard. Results: AccuIMRhyp showed much better correlation with IMR than AccuIMRbase (r=0.77 vs. 0.47, P<0.001). The diagnostic accuracy and area under the curve (AUC) for identifying significant microvascular dysfunction was higher for AccuIMRhyp than AccuIMRbase [92.1% (95% CI: 85.0-96.5%) vs. 83.2% (95% CI: 74.4-89.9%), P=0.012; 0.942 (95% CI: 0.877-0.979) vs. 0.815 (95% CI: 0.726-0.886), P=0.003]. The computed AccuFFRangio showed good correlations with FFR and good diagnostic performance under both hyperemic and baseline conditions [r=0.68 vs. 0.68, P>0.99; diagnostic accuracy =95.9% (95% CI: 89.8-98.9%) vs. 94.9% (95% CI: 88.4-98.3%), P=0.728; AUC =0.989 (95% CI: 0.942-1.000) vs. 0.973 (95% CI: 0.919-0.995), P=0.381]. The net reclassification index (NRI) demonstrated that hyperemic group had improved reclassification ability compared to the baseline group in identification of IMR >25 (NRI =0.20, P<0.001) and FFR ≤0.8 (NRI =0.11, P<0.001). Conclusions: By comparing the calculated angio-derived IMR and FFR under the baseline and hyperemic conditions, this study demonstrates that AccuIMR calculation is more accurate using the hyperemic condition, while AccuFFRangio calculation is accurate under both conditions.

Comparison of acute recoil between bioabsorbable poly-L-lactic acid XINSORB stent and metallic stent in porcine model.

OBJECTIVE: To investigate acute recoil of bioabsorbable poly-L-lactic acid (PLLA) stent. BACKGROUND: As newly developed coronary stent, bioabsorbable PLLA stent still encountered concern of acute stent recoil. METHODS: Sixteen minipigs were enrolled in our study. Eight PLLA XINSORB stents (Weite Biotechnology Co., Ltd., China) and eight metallic stents (EXCEL, Jiwei Co., Ltd. China) were implanted into coronary arteries. Upon quantitative coronary angiography analysis, acute absolute recoil was defined as the difference between mean diameter of inflated balloon (X) and mean lumen diameter of stent immediately after deployment (Y), while acute percent recoil was defined as (X-Y)/X and expressed as a percentage. Intravascular ultrasound (IVUS) was performed immediately after implantation and 24 hours later to compare cross-sectional area (CSA) between two groups and detect stent malapposition or collapse. RESULTS: Acute absolute recoil in XINSORB and EXCEL was 0.02 ± 0.13 mm and -0.08 ± 0.08 mm respectively (P = 0.19). Acute percent recoil in XINSORB and EXCEL was 0.66 ± 4.32% and -1.40 ± 3.83%, respectively (P = 0.45). CSA of XINSORB was similar to that of EXCEL immediately after implantation, so was CSA of XINSORB at 24-hours followup. Within XINSORB group, no difference existed between CSA after implantation and CSA at 24-hours followup. No sign of acute stent malapposition was detected by IVUS. CONCLUSIONS: The acute stent recoil of XINSORB is similar to that of EXCEL. No acute stent malapposition or collapse appeared in both kinds of stent. This preclinical study was designed to provide preliminary data for future studies of long-term efficacy and safety of XINSORB stent.

The role of SDF-1α/Rac pathway in the regulation of endothelial progenitor cell polarity; homing and expression of Rac1, Rac2 during endothelial repair.

The Stromal cell-derived factor-1 (SDF-1)/CXC chemokine receptor 4 (CXCR4) system is considered to be of great importance in diseases involving cardiogenesis and angiogenesis. The SDF-1α-RAC signaling pathway plays a pivotal role in a cell's polarity and serves to activate cell morphology variation and to control the direction of migration. We aimed to study whether the polarity of endothelial progenitor cells (EPCs) is changed by the induction of the SDF-1α-RAC signaling pathway, to investigate the mechanism of the effect of polarity on the homing action of EPCs, and to explore the gene and protein expression of Rac1/2 during endothelial repair. We measured the EPC characteristics of polarity induced by various final concentrations of SDF-1α; our observations included morphology variation, migration direction, and excursion. Of the dynamic variation and cytoskeleton rearrangement of EPCs induced by different final concentrations of SDF-1α, the most obvious variation was exhibited at the SDF-1α concentration of 200 ng/ml. Obvious polarity variations were also found in the EPCs and signal receptors induced by the SDF-1α concentration of 200 ng/ml. The Western blot analysis of Rac1 and Rac2 showed that the addition of AMD 3100 significantly inhibited the expression of Rac. The SDF-1α pathway potentially regulates the expression of Rac1/2. The actual excursion vector and the direction of the migration of EPCs induced by SDF-1α follows polarity, thus indicating the importance of further exploration regarding the homing induction of EPCs.

Design, synthesis and CoMFA studies of N1-amino acid substituted 2,4,5-triphenyl imidazoline derivatives as p53-MDM2 binding inhibitors.

A series of novel N1-amino-acid substituted 2,4,5-triphenyl imidazoline derivatives was designed and synthesized based on our previous studies. All synthesized target compounds were screened for their p53-MDM2 binding inhibitory activities and anti-proliferative activities against five cancer cell lines. Among them, twelve compounds displayed improved binding inhibitory activities and most compounds showed higher cell growth inhibition activities with IC(50) values in the low micromolar range. Compound 6c exhibited marked p53-MDM2 binding inhibitory activity (IC(50)=0.59 µM) which was eightfold more potent than that of Nutlin-1 (IC(50)=4.78 µM). CoMFA analysis was performed based on obtained biological data and resulted in a statistically significant CoMFA model with high predict abilities (q(2)=0.645, r(2)=0.979).