Stability of exosomes in the postmortem serum and preliminary study on exosomal miRNA expression profiling in serum from myocardial infarction cadavers.

Exosome-encapsulated miRNAs could potentially be sensitive biomarkers of human diseases. Since a lipid bilayer membrane surrounds exosomes, the exosomal miRNA may stably exist in body fluids with diseases as well as biological fluids. Therefore, exosomal miRNA may be helpful for autopsy diagnosis. Assuming cadaver blood would be most useful, we initially examined serum exosome stability with regard to storage temperatures and periods. Characteristic analyses of the exosome revealed that exosomes and the content, miRNA, were stably preserved until at least three days when stored at below 20 °C. Subsequently, exosomal miRNA expression profiling was performed on the serum of acute myocardial infarction (AMI, 4 cases) autopsy bodies and on hemorrhagic shock bodies used as the control (CT, 3 cases). Results showed that significant twofold up- and downregulations of expression of 18 and 16 miRNAs were detectable in AMI as compared to the CT, respectively. miR-126-3p, which has been reported to be increased in serum of AMI patients and a mouse model, was one of the significantly upregulated miRNAs. Furthermore, dysregulation of exosomal miRNAs, such as miR-145-5p, miR-143-3p, and miR-222-3p, which are involved in cardioprotection, may be associated with AMI pathogenesis. These findings provide a novel perspective on the potential role of exosomal miRNA in determining the cause of death.

Predictors of Irregular Protrusion After Everolimus-Eluting Stent Implantation in Patients with Stable Coronary Artery Disease.

This study aimed to investigate clinical and preintervention optical coherence tomography (OCT) findings to predict irregular protrusion (IRP) immediately after stent implantation.We evaluated 84 lesions treated with cobalt-chromium everolimus-eluting stent (CoCr-EES) from the MECHANISM Elective study. Patients were divided into two groups according to the presence of IRP [IRP: n = 16, non-IRP: n = 68]. Optical coherence tomography images before intervention and immediately after stenting were evaluated with standard qualitative and quantitative OCT analyses.Total cholesterol and the prevalence of ruptured plaque before intervention were significantly higher in the IRP group than in the non-IRP group [199 ± 37 mg/dL versus 176 ± 41 mg/dL; P = 0.022, 31% versus 7%; P = 0.008]. Total lipid length tended to be longer in the IRP group than in the non-IRP group [19.6 ± 9.2 mm versus 15.5 ± 9.3 mm; P = 0.090]. The prevalence of ruptured plaque, and total cholesterol levels were independent predictors of IRP immediately after stenting by multivariate logistic regression analysis [OR: 4.6, 95% confidence interval: 1.01-21.23, P = 0.048, OR: 1.02, 95% confidence interval: 1.00-1.03, P = 0.046]. IRP post-CoCr-EES implantation was completely resolved at follow-up OCT.The prevalence of ruptured plaque before intervention and total cholesterol levels were independent predictors of IRP after CoCr-EES implantation in patients with stable coronary artery disease.

Comparative study of different chiral ligands for dynamic kinetic resolution of amino acids.

Dynamic kinetic resolution (DKR) of unprotected amino acids (AAs), via intermediate formation of Ni(II) complexes, is currently a leading methodology for preparation of natural and tailor-made AAs in enantiomerically pure form. In this work, we conduct a comparative case study of synthetic performance of four different ligands in DKR of six AAs representing aryl-, benzyl-, alkyl-, and long alkyl-type derivatives. The results of this study allow for rational selection of ligand/AA type to develop a practical procedure for preparation of target enantiomerically pure AAs.

Comparison of serial optical coherence tomography imaging following aggressive stent expansion technique: insight from the MECHANISM study.

To compare early vascular healing following cobalt-chromium everolimus-eluting stent (CoCr-EES) implantation between groups with or without aggressive stent expansion in patients treated by CoCr-EES for stable coronary artery disease (CAD). Seventy-one stable CAD lesions underwent CoCr-EES implantation and analysis of serial optical coherence tomography (OCT) images obtained post-procedure and at early-term (1- or 3-month) follow-up. The endpoints of this study were neointimal thickness at the time of 1- or 3-month OCT and presence and healing of stent edge dissection. Aggressive stent expansion was defined as a lesion complying with ILUMIEN III sizing protocol; that is, external elastic lamina (EEL) diameter minus maximum balloon diameter ≤ 0.25 mm.  Comparing groups with and without aggressive stent expansion, median neointimal thickness at 1 and 3 months after CoCr-EES implantation was similar (1 month: 0.031 mm vs. 0.041 mm, respectively, p = 0.27; 3 months: 0.036 mm vs. 0.040 mm, respectively, p = 0.84). Regarding stent edge findings, the presence of any stent edge dissection immediately after percutaneous coronary intervention was also similar between the groups (25% vs. 15%, respectively; p = 0.30) and most stent edge dissections resolved completely within 3 months, regardless of location or dissection severity. After 1 year, no clinically driven target lesion revascularization or stent thrombosis was observed in either cohort. Even after aggressive stent expansion, early neointimal proliferation appeared modest with CoCr-EES implantation, and most stent edge dissections had resolved by 3 months. These findings may support the feasibility of EEL-based sizing by pre-stenting OCT.

Scavenger receptor MARCO contributes to cellular internalization of exosomes by dynamin-dependent endocytosis and macropinocytosis.

Macrophage receptor with collagenous structure (MARCO) is a scavenger receptor class-A protein that is expressed on the cell surface of macrophages. MARCO mediates binding and ingestion of unopsonized environmental particles, including nano-sized materials. Exosomes are cell-derived, nano-sized vesicles (40-150 nm) that can contain lipids, RNA, DNA, and various proteins. Exosomes play an essential role in cell-to-cell communication via body fluids. However, mechanisms for the recognition and internalization of exosomes by recipient cells remain poorly characterized. In this study, cellular association of serum-derived fluorescent exosomes and 20-nm fluorescent nanoparticles (positive control) was compared between MARCO-expressing (CHO-MARCO) and control (CHO-CT) CHO-K1 cells to examine whether MARCO expression by recipient cells mediates the cellular uptake of exosomes and environmental nanoparticles. Fluorescence microscopic studies and quantitative analyses revealed that the cellular associations of both exosomes and 20-nm nanoparticles were greater in CHO-MARCO cells than in CHO-CT cells. Exosomes and nanoparticles colocalized with green fluorescent protein (GFP)-MARCO in cells transfected with GFP-MARCO-encoding constructs . Furthermore, inhibitory studies showed that actin reorganization and dynamin are involved in the MARCO-mediated cellular internalization of exosomes. These results indicated that MARCO plays a role in the uptake of exosomes.

Clinical outcomes of patients treated using very short duration dual antiplatelet therapy after implantation of biodegradable-polymer drug-eluting stents: rationale and design of a prospective multicenter REIWA registry.

Several studies have demonstrated the safety and feasibility of short (3-6 months) and very short duration (< 2 months) dual antiplatelet therapy (DAPT) in patients with a durable-polymer drug-eluting stent (DP-DES). However, the clinical importance of using very short duration DAPT has yet to be established in patients with a biodegradable polymer drug-eluting stent (BP-DES). The aim of this REIWA registry (multicenter and prospective registry; investigation of clinical outcomes of patients treated with short duration dual antiplatelet therapy after implantation of biodresorbable-polymer drug-eluting stent: a multicenter, prospective registry from Iwate medical university affiliated hospitals) is to determine the safety and feasibility of using 1-month DAPT followed by P2Y12 inhibitor monotherapy in patients after BP-DES implantation. This study is an observational, prospective, multicenter registry encompassing the entire local medical region of Iwate Prefecture (northern area of mainland Japan). A total of 1200 patients who underwent successful PCI with a novel thin strut BP-DES (Synergy, Ultimaster or Orsiro) and are considered to be appropriate patients for very short DAPT, are registered and subsequently administered 1-month DAPT followed by P2Y12 inhibitor monotherapy (clopidogrel 75 mg/day or prasugrel 3.75 mg/day). The primary endpoint was a composite of cardiovascular and bleeding events, which included cardiovascular death, spontaneous myocardial infarction, definite stent thrombosis, ischemic or hemorrhagic stroke, or TIMI major or minor bleeding at 12 months. The REIWA registry (UMIN000037321) will demonstrate both the safety and feasibility of using 1-month DAPT in patients with BP-DES. Furthermore, results of this study will also be able to provide supportive evidence for P2Y12 inhibitor monotherapy after 1-month DAPT following BP-DES implantation.

Cut-off value of strut-vessel distance for the resolution of acute incomplete stent apposition in the early phase using serial optical coherence tomography after cobalt-chromium everolimus-eluting stent implantation.

OBJECTIVE: The purpose of this study was to identify a cut-off value to predict the resolution of incomplete-stent-apposition (ISA) after cobalt-chromium everolimus-eluting stent (CoCr-EES) implantation at early follow-up. BACKGROUND: To date, appropriate stent apposition at the acute period using intracoronary imaging has been recommended because persistent ISA is considered to be a risk factor for stent thrombosis. We examined the indices for resolving acute ISA. In particular, we determined the cut-off value for strut vessel distance (SV-distance) as visualized by optical coherence tomography (OCT) at 8 months after CoCr-EES implantation. However, the cut-off value of SV-distance for the earlier resolution of ISA is unclear. METHODS: A total of 95 cases and 103 stents were registered in the MECHANISM Elective substudy. The SV-distance was measured at the deepest site of the target malapposition and every 1 mm from the proximal edge to the distal edge of the mal-apposed area using OCT. Cut-off values for ISA resolution at 1 and 3 months were estimated by SV-distance using receiver operating characteristic analysis. RESULTS: The total number of analyzed struts was 14,418 at the 1-month follow-up and 11,986 at the 3-month follow-up. The optimal SV-distance cut-off values just after stent implantation to predict ISA resolution were 185 µm at the 1-month follow-up and 195 µm at the 3-month follow-up. CONCLUSION: For resolution of ISA, SV-distance cut-off values of 185 µm at 1 month postimplantation and 195 µm at 3 months postimplantation can be used as the index of endpoint of the percutaneous coronary intervention.

Practical Method for Preparation of (S)-2-Amino-5,5,5-trifluoropentanoic Acid via Dynamic Kinetic Resolution.

This work reports an operationally convenient ∼20 g scale synthesis of (S)-2-amino-5,5,5-trifluoropentanoic acid and its Fmoc-derivative via dynamic kinetic resolution of the corresponding racemate.

Cut-off value of mal-apposition volume and depth for resolution at early phase of acute incomplete stent apposition after CoCr-EES implantation.

The purpose of this study was to clarify a cut-off value for acute incomplete stent apposition (ISA) volume and maximum-depth to predict ISA resolution at 1- and 3-month follow-up in patients treated with cobalt-chromium everolimus-eluting stents. In total, 95 cases and 103 stents were registered in the MECHANISM-Elective sub-study. Acute ISA-volume was measured by the trapezoid rule. ISA resolution of cut-off value at 1- and 3-month was estimated by ISA-volume and maximum-depth using receiver operatorating characteristic curve analysis. The total number of analysed acute ISAs was 202 in the 1-month group and 225 in the 3-month group. A total of 123 ISAs at 1-month and a total of 169 ISAs at 3-month had been resolved. The cut-off value of ISA resolution by ISA-volume was 0.169 mm3 at 1-month (AUC: 0.725, sensitivity: 72.2%, specificity: 61.0%) and 0.295 mm3 at 3-month (AUC: 0.757, sensitivity: 75.0%, specificity: 60.4%). The cut-off value of ISA resolution by ISA maximum-depth demonstrated was 0.285 mm at 1-month (area under curve (AUC): 0.789, sensitivity: 70.9%, specificity: 69.9%) and 0.305 mm at 3-month (AUC: 0.663, sensitivity: 60.7%, specificity: 66.9%). Incidence of ISA resolution was significantly lower in combination with cut-off values of ISA-volume and maximum-depth (33%, p < 0.001, at 1-month; 56%, p = 0.003, at 3-month). Combining the cut-off value of ISA-volume with the maximum-depth might be helpful to consider the endpoint of the PCI procedure.

Coronary risk factors associated with OCT macrophage images and their response after CoCr everolimus-eluting stent implantation in patients with stable coronary artery disease.

BACKGROUND AND AIMS: The aim of this study was to evaluate the accumulation of optical coherence tomography (OCT)-macrophages and OCT findings after CoCr everolimus-eluting stent placement, in addition to coronary risk factors. METHODS: A total of 89 lesions in 89 patients were registered in the 1- and 3-month cohort of the multi-centre study. Lesion characteristics and post-procedure OCT images were evaluated immediately and 1 and 3 months after stenting. Patients were divided into low and high macrophage grade groups based on the median macrophage grade. RESULTS: Low-density lipoprotein cholesterol (LDL-C) levels, the prevalence of diabetes mellitus, HbA1c and blood glucose levels in the high macrophage grade group were significantly higher than in the low macrophage grade group (p = 0.025, p = 0.040, p = 0.032, and p = 0.010). Moreover, total lipid arc and length and number of thin-cap fibroatheromas (TCFAs) in the high macrophage grade group were significantly higher than in the low macrophage group (p = 0.008, p = 0.002, and p = 0.012). After CoCr everolimus-eluting stenting, there was a trend towards a greater number, height, and area of irregular protrusions in the high macrophage grade group compared to the low macrophage grade group (p = 0.091, p = 0.059, and p = 0.085). Multivariate logistic regression analysis showed that diabetes mellitus was a significant predictor of high macrophage grades (odds ratio: 2.8, 95% CI: 1.1-7.3, p = 0.030). CONCLUSIONS: The accumulation of OCT-macrophages was associated with diabetes mellitus in patients with coronary artery disease. Moreover, macrophage accumulation and diabetes mellitus may be associated with irregular protrusions just after stenting.

Chiral phosphoric acid catalyzed enantioselective transfer deuteration of ketimines by use of benzothiazoline as a deuterium donor: synthesis of optically active deuterated amines.

By use of 2-deuterated benzothiazoline as a deuterium donor in combination with a chiral phosphoric acid, the transfer deuteration of ketimine and α-iminoester took place smoothly to give α-deuterated amines in high yields with excellent enantioselectivities. The remarkable kinetic isotope effect suggests that carbon-deuterium bond cleavage is the rate-determining step.

Chiral Brønsted acid catalyzed asymmetric Friedel-Crafts alkylation reaction of indoles with α,ß-unsaturated ketones: short access to optically active 2- and 3-substituted indole derivatives.

The asymmetric Friedel-Crafts alkylation reaction of indoles with α,ß-unsaturated ketones catalyzed by chiral phosphoric acid is reported. A wide range of indoles and 4,7-dihydroindoles were allowed to react with α,ß-unsaturated ketones to give the corresponding 1,4-adducts in good to high chemical yields and with excellent enantioselectivities.