Increase of secondary metabolites in sweet basil (Ocimum basilicum L.) leaves by exposure to N2O5 with plasma technology.

Exposure to N2O5 generated by plasma technology activates immunity in Arabidopsis through tryptophan metabolites. However, little is known about the effects of N2O5 exposure on other plant species. Sweet basil synthesizes many valuable secondary metabolites in its leaves. Therefore, metabolomic analyses were performed at three different exposure levels [9.7 (Ex1), 19.4 (Ex2) and 29.1 (Ex3) µmol] to assess the effects of N2O5 on basil leaves. As a result, cinnamaldehyde and phenolic acids increased with increasing doses. Certain flavonoids, columbianetin, and caryophyllene oxide increased with lower Ex1 exposure, cineole and methyl eugenol increased with moderate Ex2 exposure and L-glutathione GSH also increased with higher Ex3 exposure. Furthermore, gene expression analysis by quantitative RT-PCR showed that certain genes involved in the syntheses of secondary metabolites and jasmonic acid were significantly up-regulated early after N2O5 exposure. These results suggest that N2O5 exposure increases several valuable secondary metabolites in sweet basil leaves via plant defense responses in a controllable system.

Utilizing plasma-generated N2O5 gas from atmospheric air as a novel gaseous nitrogen source for plants.

Fixing atmospheric nitrogen for use as fertilizer is a crucial process in promoting plant growth and enhancing crop yields in agricultural production. Currently, the chemical production of nitrogen fertilizer from atmospheric N2 relies on the energy-intensive Haber-Bosch process. Therefore, developing a low-cost and easily applicable method for fixing nitrogen from the air would provide a beneficial alternative. In this study, we tested the utilization of dinitrogen pentoxide (N2O5) gas, generated from oxygen and nitrogen present in ambient air with the help of a portable plasma device, as a nitrogen source for the model plant Arabidopsis thaliana. Nitrogen-deficient plants supplied with medium treated with N2O5, were able to overcome nitrogen deficiency, similar to those provided with medium containing a conventional nitrogen source. However, prolonged direct exposure of plants to N2O5 gas adversely affected their growth. Short-time exposure of plants to N2O5 gas mitigated its toxicity and was able to support growth. Moreover, when the exposure of N2O5 and the contact with plants were physically separated, plants cultured under nitrogen deficiency were able to grow. This study shows that N2O5 gas generated from atmospheric nitrogen can be used as an effective nutrient for plants, indicating its potential to serve as an alternative nitrogen fertilization method for promoting plant growth.

Evaluating homologous recombination activity in tissues to predict the risk of hereditary breast and ovarian cancer and olaparib sensitivity.

Homologous recombination (HR) repairs DNA damage including DNA double-stranded breaks and alterations in HR-related genes results in HR deficiency. Germline alteration of HR-related genes, such as BRCA1 and BRCA2, causes hereditary breast and ovarian cancer (HBOC). Cancer cells with HR deficiency are sensitive to poly (ADP-ribose) polymerase (PARP) inhibitors and DNA-damaging agents. Thus, accurately evaluating HR activity is useful for diagnosing HBOC and predicting the therapeutic effects of anti-cancer agents. Previously, we developed an assay for site-specific HR activity (ASHRA) that can quantitatively evaluate HR activity and detect moderate HR deficiency. HR activity in cells measured by ASHRA correlates with sensitivity to the PARP inhibitor, olaparib. In this study, we applied ASHRA to lymphoblastoid cells and xenograft tumor tissues, which simulate peripheral blood lymphocytes and tumor tissues, respectively, as clinically available samples. We showed that ASHRA could be used to detect HR deficiency in lymphoblastoid cells derived from a BRCA1 pathogenic variant carrier. Furthermore, ASHRA could quantitatively measure the HR activity in xenograft tumor tissues with HR activity that was gradually suppressed by inducible BRCA1 knockdown. The HR activity of xenograft tumor tissues quantitatively correlated with the effect of olaparib. Our data suggest that ASHRA could be a useful assay for diagnosing HBOC and predicting the efficacy of PARP inhibitors.

Lymphatic Transport and Immune Activation Effect by Locally Administered Extracellular Vesicles from Saccharomyces cerevisiae as Biocompatible Vaccine Adjuvants.

The yeast strain Saccharomyces cerevisiae is an eukaryotic organism that has been widely used for the production of fermented foods. Most cells secrete extracellular vesicles (EVs), small particles composed of lipid membranes. Elucidating the role of EVs as a new intercellular communication system and developing novel EV-based therapies have attracted the increased attention of researchers. Although recent studies have reported the secretion of EVs from S. cerevisiae, their in vivo fate and subsequent EV-mediated biological responses in the host are unclear. In this study, we characterized both the biodistribution of locally (intradermally and subcutaneously) administered Saccharomyces cerevisiae-derived EVs (S-EVs) and the EV-mediated immune responses to evaluate their potential use as biocompatible vaccine adjuvants. S-EVs were round but heterogeneous in size and contained glucan, DNA, and RNA. Their mean particle sizes and zeta potentials were approximately 177.5 nm and -14.6 mV, respectively. We provided evidence that locally administered S-EVs were delivered to the lymph nodes, mainly reaching the B-cell zone. Measurement of host immune reactions revealed that administration of S-EVs increased the expression of cytokine (tumor necrosis factor (TNF)-α) and costimulatory molecules (CD40, CD80, CD86), which are indicators of immune activation. Especially, subcutaneously injected S-EVs showed potent adjuvanticity, indicating that subcutaneous administration of S-EVs is the desirable approach for achieving effective immune stimulation. These findings will facilitate the development of novel EV-based immunotherapies.

Afterload reduction after non-invasive vagus nerve stimulation in acute heart failure.

Introduction: While central blood pressure (BP) has been recognized as a major indicator of left ventricular (LV) afterload, the reduction of central pressure decreases LV afterload and may prevent heart failure (HF) decompensation. Non-invasive transcutaneous vagus nerve stimulation (tVNS) was shown to improve cardiac function in HF patients. In this study, the relationship between active tVNS and reduction of central BP was investigated in patients with acute HF (AHF). Methods: The 22 patients hospitalized for AHF after initial stabilization (median 80 yrs, males 60%) were randomly assigned to active or sham group. For 1 h daily over 5 days, low-level transcutaneous electrical stimulation (LLTS) (20 Hz, 1 mA) was performed after attaching an ear clip to the tragus (active group) or the earlobe (sham control group). Before and after stimulation, central aortic systolic pressure (CASP), brachial systolic BP (SBP), diastolic BP (DBP) as well as heart rate (HR) were noninvasively measured. Results: No significant differences in baseline characteristics were observed between the active and sham groups. In the active group, CASP, SBP, DBP, and HR each decreased significantly after stimulation (all p < 0.05), whereas in the sham group, CASP, SBP, DBP, and HR each increased significantly after stimulation (all p < 0.05). All the changes in CASP, SBP, DBP and HR before and after stimulation were also significantly different between active and sham groups (all p < 0.01). There were no device-related side effects. Conclusion: In this study, the left tragus tVNS resulted in an acute afterload reduction in the elderly AHF patients. Non-invasive LLTS may be useful and safe for reducing afterload in AHF. Clinical trial registration: ClinicalTrials.gov, identifier UMIN000044121.

Case report: SGLT2i, transcutaneous vagus nerve stimulation, and their effects on intrarenal venous flow pattern in HFpEF.

Renal congestion in heart failure (HF) is a predictor of the prognosis of cardiovascular disease. The effect of sodium-glucose cotransporter 2 inhibitors (SGLT2i) and vagus nerve stimulation (VNS) on renal congestion has not been reported in HF. A 77-year-old man with HF with preserved ejection fraction (HFpEF) was referred to our hospital because of poor response to loop diuretics. Echocardiography showed severe tricuspid regurgitation with dilation of the right atrium. Three months after adding SGLT2i, body weight was lost without worsening of renal function. Left and right doppler-derived intrarenal venous flow (IRVF) has been changed from a monophasic to a discontinuous pattern with a systolic interruption. One month later, he discontinued SGLT2i administration at his own discretion. In order to stabilizing autonomic balance, transcutaneous VNS (tVNS) was performed via left ear tragus. One hour after transcutaneous tVNS, ipsilateral IRVF has been dramatically improved from a fusional biphasic to a discontinuous pattern with a systolic interruption. SGLT2i and tVNS may be associated with renal decongestion in HFpEF.

Activation of plant immunity by exposure to dinitrogen pentoxide gas generated from air using plasma technology.

Reactive nitrogen species (RNS) play an important role in plant immunity as signaling factors. We previously developed a plasma technology to partially convert air molecules into dinitrogen pentoxide (N2O5), an RNS whose physiological action is poorly understood. To reveal the function of N2O5 gas in plant immunity, Arabidopsis thaliana was exposed to plasma-generated N2O5 gas once (20 s) per day for 3 days, and inoculated with Botrytis cinerea, Pseudomonas syringae pv. tomato DC3000 (Pst), or cucumber mosaic virus strain yellow (CMV(Y)) at 24 h after the final N2O5 gas exposure. Lesion size with B. cinerea infection was significantly (P < 0.05) reduced by exposure to N2O5 gas. Propagation of CMV(Y) was suppressed in plants exposed to N2O5 gas compared with plants exposed to the air control. However, proliferation of Pst in the N2O5-gas-exposed plants was almost the same as in the air control plants. These results suggested that N2O5 gas exposure could control plant disease depending on the type of pathogen. Furthermore, changes in gene expression at 24 h after the final N2O5 gas exposure were analyzed by RNA-Seq. Based on the gene ontology analysis, jasmonic acid and ethylene signaling pathways were activated by exposure of Arabidopsis plants to N2O5 gas. A time course experiment with qRT-PCR revealed that the mRNA expression of the transcription factor genes, WRKY25, WRKY26, WRKY33, and genes for tryptophan metabolic enzymes, CYP71A12, CYP71A13, PEN2, and PAD3, was transiently induced by exposure to N2O5 gas once for 20 s peaking at 1-3 h post-exposure. However, the expression of PDF1.2 was enhanced beginning from 6 h after exposure and its high expression was maintained until 24-48 h later. Thus, enhanced tryptophan metabolism leading to the synthesis of antimicrobial substances such as camalexin and antimicrobial peptides might have contributed to the N2O5-gas-induced disease resistance.

Synergistic regulation of hepatic Fsp27b expression by HNF4α and CREBH.

The CIDE (cell death-inducing DFF45-like effector) family composed of CIDEA, CIDEB, CIDEC/FSP27 (fat-specific protein 27), has a critical role in growth of lipid droplets. Of these, CIDEB and CIDEC2/FSP27B are abundant in the liver, and the steatotic livers, respectively. Hepatocyte nuclear factor 4α (HNF4α) has an important role in lipid homeostasis because liver-specific HNF4α-null mice (Hnf4aΔHep mice) exhibit hepatosteatosis. We investigated whether HNF4α directly regulates expression of CIDE family genes. Expression of Cideb and Fsp27b was largely decreased in Hnf4aΔHep mice, while expression of Cidea was increased. Similar results were observed only in CIDEC2, the human orthologue of the Fsp27b, in human hepatoma cell lines in which HNF4α expression was knocked down. Conversely, overexpression of HNF4α strongly induced CIDEC2 expression in hepatoma cell lines. Furthermore, HNF4α transactivated Fsp27b by direct binding to an HNF4α response element in the Fsp27b promoter. In addition, Fsp27b is known to be transactivated by CREBH that is regulated by HNF4α, and expression of CREBH was induced by HNF4α in human hepatoma cells. Co-transfection of HNF4α and CREBH resulted in synergistic transactivation and induction of Fsp27b compared to that of HNF4α or CREBH alone. These results suggest that HNF4α, in conjunction with CREBH, plays an important role in regulation of Fsp27b expression.

TRPA1 and TRPV1 channels participate in atmospheric-pressure plasma-induced [Ca2+]i response.

Despite successful clinical application of non-equilibrium atmospheric pressure plasma (APP), the details of the molecular mechanisms underlying APP-inducible biological responses remain ill-defined. We previously reported that exposure of 3T3L1 cells to APP-irradiated buffer raised the cytoplasmic free Ca2+ ([Ca2+]i) concentration by eliciting Ca2+ influx in a manner sensitive to transient receptor potential (TRP) channel inhibitors. However, the precise identity of the APP-responsive channel molecule(s) remains unclear. In the present study, we aimed to clarify channel molecule(s) responsible for indirect APP-responsive [Ca2+]i rises. siRNA-mediated silencing experiments revealed that TRPA1 and TRPV1 serve as the major APP-responsive Ca2+ channels in 3T3L1 cells. Conversely, ectopic expression of either TRPA1 or TRPV1 in APP-unresponsive C2C12 cells actually triggered [Ca2+]i elevation in response to indirect APP exposure. Desensitization experiments using 3T3L1 cells revealed APP responsiveness to be markedly suppressed after pretreatment with allyl isothiocyanate or capsaicin, TRPA1 and TRPV1 agonists, respectively. APP exposure also desensitized the cells to these chemical agonists, indicating the existence of a bi-directional heterologous desensitization property of APP-responsive [Ca2+]i transients mediated through these TRP channels. Mutational analyses of key cysteine residues in TRPA1 (Cys421, Cys621, Cys641, and Cys665) and in TRPV1 (Cys258, Cys363, and Cys742) have suggested that multiple reactive oxygen and nitrogen species are intricately involved in activation of the channels via a broad range of modifications involving these cysteine residues. Taken together, these observations allow us to conclude that both TRPA1 and TRPV1 channels play a pivotal role in evoking indirect APP-dependent [Ca2+]i responses.

Hepatocyte nuclear factor 4α regulates megalin expression in proximal tubular cells.

Hepatocyte nuclear factor 4α (HNF4α) is a member of the nuclear receptor superfamily and upregulates expression of many genes in the liver, pancreas, small intestine, and colon. HNF4α is also highly expressed in proximal tubular epithelial cells (PTECs) in kidney. PTECs reabsorb various substances through transporters, ion channels, and receptors, but the target genes for HNF4α in PTECs have not been investigated in detail. In the present study, we aimed to identify novel HNF4α target genes that are highly expressed in PTECs. Expression of many solute carrier transporter genes was upregulated by HNF4α in human PTEC-derived HK-2 cells. Notably, expression of megalin (LRP2), an endocytic receptor of various molecules involved in development and progression of chronic kidney disease (CKD), was strongly induced by HNF4α, and the transactivation potential of the megalin promoter was dependent on HNF4α expression. Moreover, HNF4α was found to directly bind to an HNF4α binding site near the transcription start site in the megalin gene. These results indicate that HNF4α plays an important role in maintaining reabsorption and metabolism in PTECs by positive regulation of several solute carrier transporter and megalin genes at the transcriptional level.

Induction of Hepatic Metabolic Functions by a Novel Variant of Hepatocyte Nuclear Factor 4γ.

Hepatocyte nuclear factor 4α (HNF4α) is a critical factor for hepatocyte differentiation. HNF4α expression is decreased in hepatocellular carcinoma (HCC), which suggests a role in repression of hepatocyte dedifferentiation. In the present study, hepatic expression of HNF4γ was increased in liver-specific Hnf4a-null mice. The HNF4γ whose expression was increased contained two variants, a known short variant, designated HNF4γ1, and a novel long variant, designated HNF4γ2. HNF4G2 mRNA was highly expressed in small intestine, and the transactivation potential of HNF4γ2 was the strongest among these variants, but the potential of HNF4γ1 was the lowest. Cotransfection experiments revealed that HNF4γ1 repressed HNF4α- and HNF4γ2-dependent transactivation, while HNF4γ2 promoted HNF4α-dependent transactivation. HNF4γ1 and HNF4γ2 were able to bind to the HNF4α binding sites with an affinity similar to that of HNF4α. Furthermore, HNF4γ2, but not HNF4γ1, robustly induced the expression of typical HNF4α target genes to a greater degree than HNF4α. Additionally, HNF4γ2 suppressed proliferation of hepatoma cells as well as HNF4α and HNF4γ1 did, and HNF4γ2 induced critical hepatic functions, such as glucose and urea production, and cytochrome P450 1A2 activity more strongly than HNF4α and HNF4γ1 did. These results indicate that HNF4γ2 has potential for redifferentiation of HCC and thus may be explored as a target for HCC therapy.

Elucidation of Spatial Distribution of Hydrophobic Aromatic Compounds Encapsulated in Polymer Micelles by Anomalous Small-Angle X-ray Scattering.

Spatial distribution of bromobenzene (BrBz) and 4-bromophenol (BrPh) as hydrophobic aromatic compounds incorporated in polymer micelles with vesicular structure consisting of poly(ethylene glycol)-b-poly(tert-butyl methacrylate) (PEG-b-PtBMA) in aqueous solution is investigated by anomalous small-angle X-ray scattering (ASAXS) analyses near Br K edge. Small-angle X-ray scattering (SAXS) intensities from PEG-b-PtBMA micelles containing BrBz and BrPh were decreased as the energy of incident X-ray approached to Br K edge corresponding to the energy dependence of anomalous scattering factor of Br. The analysis for the energy dependence of SAXS profiles from the PEG-b-PtBMA micelles containing BrBz revealed that BrBz molecules were located in hydrophobic layer of PEG-b-PtBMA micelles. On the contrary, it was found by ASAXS that BrPh existed not only in the hydrophobic layer but also in the shell layer. Since ASAXS analysis successfully accomplished to visualize the spatial distribution of hydrophobic molecules in polymer micelles, it should be expected to be a powerful tool for characterization of drug delivery vehicles.

Cold atmospheric plasma enhances osteoblast differentiation.

This study was designed to assess the effects of cold atmospheric plasma on osteoblastic differentiation in pre-osteoblastic MC3T3-E1 cells. Plasma was irradiated directly to a culture medium containing plated cells for 5 s or 10 s. Alkaline phosphatase (ALP) activity assay and alizarin red staining were applied to assess osteoblastic differentiation. The plasma-generated radicals were detected directly using an electron spin resonance-spin trapping technique. Results show that plasma irradiation under specific conditions increased ALP activity and enhanced mineralization, and demonstrated that the yield of radicals was increased in an irradiation-time-dependent manner. Appropriate plasma irradiation stimulated the osteoblastic differentiation of the cells. This process offers the potential of promoting bone regeneration.

Visit-to-Visit Blood Pressure Variability and Alzheimer's Disease: Links and Risks.

While hypertension has been shown to be a risk factor for vascular dementia, several studies have also demonstrated that hypertension also increases the risk of Alzheimer's disease (AD). Although the relationship between visit-to-visit blood pressure variability (VVV) and cognitive impairment, including AD, have been provided, the mechanisms remain poorly understood. This review paper focuses on the relationship of VVV with AD and summarizes the pathophysiology underlying that relationship, which appears to be mediated by arterial stiffness.

An HNF4α-microRNA-194/192 signaling axis maintains hepatic cell function.

Hepatocyte nuclear factor 4α (HNF4α) controls the expression of liver-specific protein-coding genes. However, some microRNAs are also modulated by HNF4α, and it is not known whether they are direct targets of HNF4α and whether they influence hepatic function. In this study, we found that HNF4α regulates microRNAs, indicated by marked down-regulation of miR-194 and miR-192 (miR-194/192) in liver-specific Hnf4a-null (Hnf4aΔH) mice. Transactivation of the shared miR-194/192 promoter was dependent on HNF4α expression, indicating that miR-194/192 is a target gene of HNF4α. Screening of potential mRNAs targeted by miR-194/192 revealed that expression of genes involved in glucose metabolism (glycogenin 1 (Gyg1)), cell adhesion and migration (activated leukocyte cell adhesion molecule (Alcam)), tumorigenesis and tumor progression (Rap2b and epiregulin (Ereg)), protein SUMOylation (Sumo2), epigenetic regulation (Setd5 and Cullin 4B (Cln4b)), and the epithelial-mesenchymal transition (moesin (Msn)) was up-regulated in Hnf4aΔH mice. Moreover, we also found that miR-194/192 binds the 3'-UTR of these mRNAs. siRNA knockdown of HNF4α suppressed miR-194/192 expression in human hepatocellular carcinoma (HCC) cells and resulted in up-regulation of their mRNA targets. Inhibition and overexpression experiments with miR-194/192 revealed that Gyg1, Setd5, Sumo2, Cln4b, and Rap2b are miR-194 targets, whereas Ereg, Alcam, and Msn are miR-192 targets. These findings reveal a novel HNF4α network controlled by miR-194/192 that may play a critical role in maintaining the hepatocyte-differentiated state by inhibiting expression of genes involved in dedifferentiation and tumorigenesis. These insights may contribute to the development of diagnostic markers for early HCC detection, and targeting of the miR-194/192 pathway could be useful for managing HCC.

Gas-liquid interfacial plasmas producing reactive species for cell membrane permeabilization.

Gas-liquid interfacial atmospheric-pressure plasma jets (GLI-APPJ) are used medically for plasma-induced cell-membrane permeabilization. In an attempt to identify the dominant factors induced by GLI-APPJ responsible for enhancing cell-membrane permeability, the concentration and distribution of plasma-produced reactive species in the gas and liquid phase regions are measured. These reactive species are classified in terms of their life-span: long-lived (e.g., H2O2), short-lived (e.g., O2•-), and extremely-short-lived (e.g., •OH). The concentration of plasma-produced •OHaq in the liquid phase region decreases with an increase in solution thickness (<1 mm), and plasma-induced cell-membrane permeabilization is found to decay markedly as the thickness of the solution increases. Furthermore, the horizontally center-localized distribution of •OHaq, resulting from the center-peaked distribution of •OH in the gas phase region, corresponds with the distribution of the permeabilized cells upon APPJ irradiation, whereas the overall plasma-produced oxidizing species such as H2O2aq in solution exhibit a doughnut-shaped horizontal distribution. These results suggest that •OHaq is likely one of the dominant factors responsible for plasma-induced cell-membrane permeabilization.

The Insular Cortex and Takotsubo Cardiomyopathy.

Transient left ventricular dysfunction in patients under emotional stress, also known as Takotsubo cardiomyopathy, has been recognized as a distinct clinical entity. Recent studies have supported the concept notion that the cardiovascular system is regulated by cortical modulation. A network consisting of the insular cortex (Ic), anterior cingulate gyrus, and amygdala plays a crucial role in the regulation of the central autonomic nervous system in relation to emotional stress such as anxiety, fear and sadness. Because the Ic is located in the region of the middle cerebral arteries, its structure tends to be exposed to a higher risk of cerebrovascular disease. Ic damage has been associated with myocardial injury, increased brain natriuretic peptide, and the incidence of Takotsubo cardiomyopathy. Because Ic damage has been associated with increased sympathetic nervous system activity, Ic damage is suggested to have a pivotal role in the pathophysiology of Takotsubo cardiomyopathy. In this review, we focus on the role of the Ic as a mediator for the cardiovascular system in relation to emotional stress, and we summarizes the current knowledge on the relationships between the Ic and Takotsubo cardiomyopathy.

Calcium influx through TRP channels induced by short-lived reactive species in plasma-irradiated solution.

Non-equilibrium helium atmospheric-pressure plasma (He-APP), which allows for a strong non-equilibrium chemical reaction of O2 and N2 in ambient air, uniquely produces multiple extremely reactive products, such as reactive oxygen species (ROS), in plasma-irradiated solution. We herein show that relatively short-lived unclassified reactive species (i.e., deactivated within approximately 10 min) generated by the He-APP irradiation can trigger physiologically relevant Ca(2+) influx through ruthenium red- and SKF 96365-sensitive Ca(2+)-permeable channel(s), possibly transient receptor potential channel family member(s). Our results provide novel insight into understanding of the interactions between cells and plasmas and the mechanism by which cells detect plasma-induced chemically reactive species, in addition to facilitating development of plasma applications in medicine.

Intravascular ultrasound for morphological assessment of napkin-ring sign detected on multidetector computed tomography.

BACKGROUND: Although napkin-ring sign (NRS) plaques assessed by multidetector computed tomography (MDCT) is identified as a high-risk feature, the detailed morphological features are still unknown. The purpose of this study was to elucidate the morphological features of the MDCT-assessed NRS using intravascular ultrasound (IVUS). METHODS: We evaluated 204 plaques in 193 patients with non-ST-elevation acute coronary syndrome who were diagnosed using 128-slice MDCT and were assessed using IVUS prior to coronary intervention. Morphology was compared between plaques with and without MDCT-assessed NRS. Severe IVUS-assessed attenuation was defined as an attenuation angle >180°. RESULTS: NRS was detected in 49 lesions. MDCT-assessed plaque attenuation was lower (p<0.0001), and cross-sectional plaque areas at lesion sites, remodeling index, and the prevalence of positive remodeling were greater, in lesions with NRS (p<0.005, p<0.0001, and p<0.0001, respectively). Furthermore, the IVUS-assessed remodeling index and prevalence of severe attenuation and speckled echo appearance were significantly greater in lesions with NRS (p<0.01, p<0.0001, and p<0.0001, respectively). Using multivariate analysis, IVUS-assessed speckled echo appearance was identified as an independent predictor of MDCT-assessed NRS (odds ratio, 3.59; 95% confidence interval, 1.49-8.66; p<0.005). CONCLUSION: MDCT assessment of NRS may be associated with larger heterogeneous necrotic cores and greater positive remodeling.