Human iPSC-derived Committed Cardiac Progenitors Generate Cardiac Tissue Grafts in a Swine Ischemic Cardiomyopathy Model without Triggering Ventricular Arrhythmias

BACKGROUND

The adult human heart following a large myocardial infarction is unable to regenerate heart muscle and instead forms scar with the risk of progressive heart failure. Large animal studies have shown that intramyocardial injection of human pluripotent stem cell-derived cardiomyocytes (hPSC-CMs) following a myocardial infarction result in cell grafts but also ventricular arrhythmias. We hypothesized that intramyocardial injection of committed cardiac progenitor cells (CCPs) derived from iPSCs, combined with cardiac fibroblast-derived extracellular matrix (cECM) to enhance cell retention will: i) form cardiomyocyte containing functional grafts, ii) be free of ventricular arrhythmias and iii) restore left ventricular contractility in a post-myocardial infarction (MI) cardiomyopathy swine model.

METHODS

hiPSCs were differentiated using bioreactors and small molecules to produce a population of committed cardiac progenitor cells (CCPs). MI was created using a coronary artery balloon occlusion and reperfusion model in Yucatan mini pigs. Four weeks later, epicardial needle injections of CCPs+cECM were performed in a small initial feasibility cohort, and then transendocardial injections (TEI) of CCPs+cECM, CCPs alone, cECM alone or vehicle control into the peri-infarct region in a larger randomized cohort. A 4-drug immunosuppression regimen was administered to prevent rejection of human CCPs. Arrhythmias were evaluated using implanted event recorders. Magnetic resonance imaging (MRI) and invasive pressure volume assessment were used to evaluate left ventricular anatomic and functional performance, including viability. Detailed histology was performed on the heart to detect human grafts.

RESULTS

A scalable biomanufacturing protocol was developed generating CCPs which can efficiently differentiate to cardiomyocytes or endothelial cells in vitro. Intramyocardial delivery of CCPs to post-MI porcine hearts resulted in engraftment and differentiation of CCPs to form ventricular cardiomyocyte rich grafts. There was no significant difference in cardiac MRI-based measured cardiac volumes or function between control, CCP and CCP+cECM groups; however, dobutamine stimulated functional reserve was improved in CCP and CCP+cECM groups. TEI delivery of CCPs with or without cECM did not result in tumors or trigger ventricular arrhythmias.

CONCLUSIONS

CCPs are a promising cell source for post-MI heart repair using clinically relevant TEI with a low risk of engraftment ventricular arrhythmias.

Induced Pluripotent Stem Cell-Derived Cardiomyocytes Therapy for Ischemic Heart Disease in Animal Model: A Meta-Analysis

Ischemic heart disease (IHD) poses a significant challenge in cardiovascular health, with current treatments showing limited success. Induced pluripotent derived-cardiomyocyte (iPSC-CM) therapy within regenerative medicine offers potential for IHD patients, although its clinical impacts remain uncertain. This study utilizes meta-analysis to assess iPSC-CM outcomes in terms of efficacy and safety in IHD animal model studies. A meta-analysis encompassing PUBMED, ScienceDirect, Web of Science, and the Cochrane Library databases, from inception until October 2023, investigated iPSC therapy effects on cardiac function and safety outcomes. Among 51 eligible studies involving 1012 animals, despite substantial heterogeneity, the iPSC-CM transplantation improved left ventricular ejection fraction (LVEF) by 8.23% (95% CI, 7.15 to 9.32%; p < 0.001) compared to control groups. Additionally, cell-based treatment reduced the left ventricle fibrosis area and showed a tendency to reduce left ventricular end-systolic volume (LVESV) and end-diastolic volume (LVEDV). No significant differences emerged in mortality and arrhythmia risk between iPSC-CM treatment and control groups. In conclusion, this meta-analysis indicates iPSC-CM therapy's promise as a safe and beneficial intervention for enhancing heart function in IHD. However, due to observed heterogeneity, the efficacy of this treatment must be further explored through large randomized controlled trials based on rigorous research design.

In vivo tracking transplanted cardiomyocytes derived from human induced pluripotent stem cells using nuclear medicine imaging

Introduction

Transplantation of human induced pluripotent stem cell-derived cardiomyocytes (iPSC-CMs) is a promising treatment for heart failure. Information on long-term cell engraftment after transplantation is clinically important. However, clinically applicable evaluation methods have not yet been established.

Methods

In this study, to noninvasively assess transplanted cell engraftment, human SLC5A5, which encodes a sodium/iodide symporter (NIS) that transports radioactive tracers such as 125I, 18F-tetrafluoroborate (TFB), and 99mTc-pertechnetate (99mTcO4-), was transduced into human induced pluripotent stem cells (iPSCs), and nuclear medicine imaging was used to track engrafted human iPSC-CMs.

Results

To evaluate the pluripotency of NIS-expressing human iPSCs, they were subcutaneously transplanted into immunodeficient rats. Teratomas were detected by 99mTcO4- single photon emission computed tomography (SPECT/CT) imaging. NIS expression and the uptake ability of 125I were maintained in purified human iPSC-CMs. NIS-expressing human iPSC-CMs transplanted into immunodeficient rats could be detected over time using 99mTcO4- SPECT/CT imaging. Unexpectedly, NIS expression affected cell proliferation of human iPSCs and iPSC-derived cells.

Discussion

Such functionally designed iPSC-CMs have potential clinical applications as a noninvasive method of grafted cell evaluation, but further studies are needed to determine the effects of NIS transduction on cellular characteristics and functions.

Evidence for Hypoxia-Induced Shift in ATP Production from Glycolysis to Mitochondrial Respiration in Pulmonary Artery Smooth Muscle Cells in Pulmonary Arterial Hypertension

BACKGROUND

The metabolic state of pulmonary artery smooth muscle cells (PASMCs) from patients with pulmonary arterial hypertension (PAH) is not well understood. In this study, we examined the balance between glycolysis and mitochondrial respiration in non-PAH-PASMCs and PAH-PASMCs under normoxia and hypoxia.

METHODS

We investigated the enzymes involved in glycolysis and mitochondrial respiration, and studied the two major energy-yielding pathways (glycolysis and mitochondrial respiration) by measuring extracellular acidification rate (ECAR) and cellular oxygen consumption rate (OCR) using the Seahorse extracellular flux technology.

RESULTS

Under both normoxia and hypoxia, the mRNA and protein levels of pyruvate dehydrogenase kinase 1 and pyruvate dehydrogenase were increased in PAH-PASMCs compared with non-PAH-PASMCs. The mRNA and protein levels of lactate dehydrogenase, as well as the intracellular lactate concentration, were also increased in PAH-PASMCs compared with non-PAH-PASMCs under normoxia. However, these were not significantly increased in PAH-PASMCs compared with non-PAH-PASMCs under hypoxia. Under normoxia, ATP production was significantly lower in PAH-PASMCs (59 ± 5 pmol/min) than in non-PAH-PASMCs (70 ± 10 pmol/min). On the other hand, ATP production was significantly higher in PAH-PASMCs (31 ± 5 pmol/min) than in non-PAH-PASMCs (14 ± 3 pmol/min) under hypoxia.

CONCLUSIONS

There is an underlying change in the metabolic strategy to generate ATP production under the challenge of hypoxia.

Effects of Agalsidase Alfa Enzyme Replacement Therapy on Left Ventricular Hypertrophy on Electrocardiogram in a Female Patient with Fabry Disease

Fabry disease is an X-linked lysosomal storage disorder caused by defective enzyme activity of α-galactosidase A and treated with enzyme replacement therapy (ERT) with recombinant α-galactosidase. ERT reduces left ventricular mass assessed by echocardiography or magnetic resonance imaging. However, electrocardiogram changes during ERT have not been fully elucidated. In the present case, ERT with agalsidase alfa for 4 years decreased QRS voltage and negative T depth along with a reduction of left ventricular mass and wall thickness and improvement of symptoms in a female patient with Fabry disease. Long-term observation of electrocardiogram changes might be useful for determining the efficacy of ERT in this case.

Microcalcification and 99mTc-Pyrophosphate Uptake without Increased Bone Metabolism in Cardiac Tissue from Patients with Transthyretin Cardiac Amyloidosis

Transthyretin cardiac amyloidosis (ATTR-CA) is characterized by high ^99mTc-labeled bone tracer uptake in the heart. However, the mechanism of bone tracer uptake into the heart remains controversial. Since bone tracer uptake into metastatic bone tumors is thought to be associated with increased bone metabolism, we examined ^99mTc-pyrophosphate (PYP) scintigraphy findings, endomyocardial biopsy (EMB) tissue findings, and the expression of bone metabolism-related genes in the EMB tissues in patients with ATTR-CA, amyloid light-chain cardiac amyloidosis (AL-CA), and noncardiac amyloidosis (non-CA) in this study. The uptake of ^99mTc-PYP in the heart was significantly higher in the ATTR-CA patients than in the AL-CA and non-CA patients. A higher percentage of ATTR-CA EMB tissue showed von Kossa-positive microparticles: ATTR-CA, 62%; AL-CA, 33%; and non-CA, 0%. Calcified microparticles were identified using transmission electron microscopy. However, none of the osteogenic marker genes, osteoclastic marker genes, or phosphate/pyrophosphate-related genes were upregulated in the EMB samples from ATTR-CA patients compared to those from AL-CA and non-CA patients. These results suggest that active calcification-promoting mechanisms are not involved in the microcalcification observed in the heart in ATTR-CA. The mechanisms explaining bone tracer uptake in the heart, which is stronger than that in the ribs, require further investigation.

BepiColombo mission confirms stagnation region of Venus and reveals its large extent

The second Venus flyby of the BepiColombo mission offer a unique opportunity to make a complete tour of one of the few gas-dynamics dominated interaction regions between the supersonic solar wind and a Solar System object. The spacecraft pass through the full Venusian magnetosheath following the plasma streamlines, and cross the subsolar stagnation region during very stable solar wind conditions as observed upstream by the neighboring Solar Orbiter mission. These rare multipoint synergistic observations and stable conditions experimentally confirm what was previously predicted for the barely-explored stagnation region close to solar minimum. Here, we show that this region has a large extend, up to an altitude of 1900 km, and the estimated low energy transfer near the subsolar point confirm that the atmosphere of Venus, despite being non-magnetized and less conductive due to lower ultraviolet flux at solar minimum, is capable of withstanding the solar wind under low dynamic pressure.

Effects of Arterial Stiffness on Cerebral WM Integrity in Older Adults: A Neurite Orientation Dispersion and Density Imaging and Magnetization Transfer Saturation Imaging Study

BACKGROUND AND PURPOSE

Arterial stiffness is reported to be able to cause axonal demyelination or degeneration. The present study aimed to use advanced MR imaging techniques to examine the effect of arterial stiffness on the WM microstructure among older adults.

MATERIALS AND METHODS

Arterial stiffness was measured using the cardio-ankle vascular elasticity index (CAVI). The high-CAVI (mean CAVI ≥ 9 points) and the low-CAVI groups (mean CAVI < 9 points) were created. The neuronal fiber integrity of the WM was evaluated by neurite orientation dispersion and density imaging and magnetization transfer saturation imaging. Tract-Based Spatial Statistics and the tracts-of-interest analysis were performed. Specific WM regions (corpus callosum, internal capsule, anterior thalamic radiation, corona radiata, superior longitudinal fasciculus, forceps minor, and inferior fronto-occipital fasciculus) were selected in the tracts-of-interest analysis.

RESULTS

In Tract-Based Spatial Statistics, the high-CAVI group showed a significantly lower myelin volume fraction value in the broad WM and significantly higher radial diffusivity and isotropic volume fraction values in the corpus callosum, forceps minor, inferior fronto-occipital fasciculus, internal capsule, corona radiata, and anterior thalamic radiation than the low-CAVI group. In tracts-of-interest analysis using multivariate linear regression, significant associations were found between the mean CAVI and radial diffusivity in the anterior thalamic radiation and the corona radiata; isotropic volume fraction in the anterior thalamic radiation and the corona radiata; and myelin volume fraction in the superior longitudinal fasciculus (P < .05). Additionally, partial correlation coefficients were observed for the significant associations of executive function with radial diffusivity and myelin volume fraction (P < .05).

CONCLUSIONS

Arterial stiffness could be associated with demyelination rather than axonal degeneration.

Direct observations of energy transfer from resonant electrons to whistler-mode waves in magnetosheath of Earth

Electromagnetic whistler-mode waves in space plasmas play critical roles in collisionless energy transfer between the electrons and the electromagnetic field. Although resonant interactions have been considered as the likely generation process of the waves, observational identification has been extremely difficult due to the short time scale of resonant electron dynamics. Here we show strong nongyrotropy, which rotate with the wave, of cyclotron resonant electrons as direct evidence for the locally ongoing secular energy transfer from the resonant electrons to the whistler-mode waves using ultra-high temporal resolution data obtained by NASA’s Magnetospheric Multiscale (MMS) mission in the magnetosheath. The nongyrotropic electrons carry a resonant current, which is the energy source of the wave as predicted by the nonlinear wave growth theory. This result proves the nonlinear wave growth theory, and furthermore demonstrates that the degree of nongyrotropy, which cannot be predicted even by that nonlinear theory, can be studied by observations.

Excitation of whistler-mode waves by cyclotron instability is considered as the likely generation process of the waves. Here, the authors show direct observational evidence for locally ongoing secular energy transfer from the resonant electrons to the whistler-mode waves in Earth’s magnetosheath.

Increasing the class of foundational medication for heart failure is associated with improved prognosis in hospitalized patients with heart failure with reduced or mildly reduced ejection fraction

Aim

To clarify the association between changes in the number of foundational medications for heart failure (FMHF) during hospitalization for worsening heart failure and post-discharge prognosis.

Methods and results

We retrospectively analyzed a combined dataset of three large-scale registries of hospitalized patients with heart failure in Japan (NARA-HF, WET-HF, and REALITY-AHF) and included patients already diagnosed with heart failure with reduced or mildly reduced left ventricular ejection fraction (HFr/mrEF) before admission. Patients were stratified by changes in the number of prescribed FMHF classes, namely angiotensin-converting enzyme inhibitors or angiotensin receptor blockers, beta blockers, and mineralocorticoid receptor blockers, from admission to discharge. The primary endpoint was defined as the combined endpoint of heart failure rehospitalization and all-cause death within 1-year of discharge. The cohort consisted of 1,113 patients, and 482 combined endpoints were observed. In total, 413 (37.1%) patients were on increased FMHF (increased group), 607 (54.5%) remained unchanged (unchanged group), and 93 (8.4%) had a decreased number of FMHF (decreased group) at discharge compared to the time of admission. In multivariable analysis, the increased group was associated with a significantly lower incidence of the primary endpoint compared with the unchanged group (hazard ratio 0.56, 95% confidence interval 0.45–0.60; P&lt;0.001) and decreased group (hazard ratio 0.58, 95% confidence interval 0.40–0.84; P=0.004).

Conclusion

Increasing the number of FMHF cases during heart failure hospitalization is associated with a better prognosis in patients with HFr/mrEF.

Funding Acknowledgement

Type of funding sources: Foundation. Main funding source(s): REALITY registry was funded by the Cardiovascular Research Fund of Japan.WET-HF registry was supported by a Grant-in-Aid for Young Scientists (Y.S. JSPS KAKENHI, 18K15860).

Derivation and validation of a machine learning-based risk prediction model for in-hospital mortality in patients with acute heart failure

Background

Although risk stratification is important in patients with acute heart failure (AHF) to predict patient prognosis, pre-existing risk models have not often been used due to its complexity. Recently, machine learning methods have been presented as an alternative approach to analyzing the predictive probability of large clinical datasets.

Purpose

The aim of this study is to develop a user-friendly risk score developed by one of machine learning methods and compare the performance of the new risk score to the existing conventional risk models.

Methods

A machine-learning-based risk model was developed using least absolute shrinkage and selection operator (LASSO) regression by identifying predictors of in-hospital mortality in the derivation cohort (REALITY-AHF) and externally validating and comparing its performance with two pre-existing risk models: the Get With The Guidelines risk score incorporating brain natriuretic peptide and hypochloremia (GWTG-BNP-Cl-RS) and the acute decompensated heart failure national registry (ADHERE) risk model.

Results

In-hospital deaths in the derivation and validation (NARA-HF) cohorts were 76 (5.1%) and 61 (4.9%), respectively. The risk score comprised four variables (systolic blood pressure, blood urea nitrogen, serum chloride, and C-reactive protein) and was developed according to the results of the LASSO regression weighting the coefficient for selected variables using a logistic regression model (4V-RS). Even though 4V-RS comprised fewer variables, In the validation cohort, it showed a higher area under the receiver operating characteristic curve (AUC) than the ADHERE risk model (AUC, 0.783 vs. 0.740; P=0.059) and a significant improvement in net reclassification (0.359; 95% CI, 0.10–0.67; p=0.006). 4V-RS performed similarly to GWTG-BNP-Cl-RS in terms of discrimination (AUC, 0.783 vs. 0.759; p=0.426) and net reclassification (0.176; 95% CI, −0.08–0.43; p=0.178).

Conclusions

The 4V-RS model comprising only four readily available data points at the time of admission performed similarly to the more complex pre-existing risk model in patients with AHF.

Funding Acknowledgement

Type of funding sources: Foundation. Main funding source(s): Cardiovascular Research Fund

Predicting new-onset heart failure hospitalization of patients with atrial fibrillation: development and external validations of a risk score

Background

Atrial fibrillation (AF) is a well-known risk factor for heart failure (HF), and HF development as a complication of AF is associated with a decline in the quality of life and poor prognosis. However, unlike thrombotic events, incidence of HF in patients with AF has not changed for decades, and a preventive strategy has yet to be developed.

Purpose

We sought to develop a risk model for new-onset HF admission in patients with AF and without a history of HF. Additionally, we attempted to externally validate the developed risk model.

Methods

We utilized two multicenter, prospective, observational registries of AF and analyzed the patients without a history of AF. One of which is defined as a derivation cohort, which included 2,857 patients, and the other is defined as a validation cohort, which included 2,516 patients. We developed a risk model by selecting variables with regularized regression and weighing coefficients by Cox regression analysis with the derivation cohort. The external validity was tested in the validation cohort.

Results

During the follow-up period, 148 patients (5.2%) in the derivation cohort and 104 patients (4.1%) in the validation cohort developed HF during the median follow-up period of 1,396 (interquartile range [IQR]: 1,078–1,820) days and 1,168 (IQR: 844–1,309) days, respectively. In the derivation cohort, four predictors (age, hemoglobin, serum creatinine, and log-transformed brain natriuretic peptide) were identified as potential risk factors for HF development. The developed risk model showed good discrimination and calibration in both the derivation (area under the curve [AUC], 0.77 [95% confidence interval (CI) 0.73–0.81]; Hosmer-Lemeshow test, P=0.257) and validation cohorts (AUC: 0.76 [95% CI 0.72–0.81]; Hosmer-Lemeshow test, P=0.475). Considering death not due to HF as a competing risk, the cumulative incidence curves for HF admission stratified by the risk score were generated, which showed higher HF hospitalization rate for the higher risk score categories.

Conclusion

The newly developed risk model with four readily available clinical characteristics and biomarkers performed well in the prediction of new-onset HF admission of patients with AF in both derivation and validation cohort.

Funding Acknowledgement

Type of funding sources: None.

Quantitative estimation of pulmonary artery wedge pressure from chest radiographs by a regression convolutional neural network

Introduction

Recent studies reported that a convolutional neural network (CNN; a deep learning model) can detect elevated pulmonary artery wedge pressure (PAWP) from chest radiographs, the diagnostic images most commonly used for assessing pulmonary congestion in heart failure. However, no method has been published for quantitatively estimating PAWP from such radiographs. We hypothesized that a regression CNN, an alternative type of deep learning, could be a useful tool for quantitatively estimating PAWP from chest radiographs in cardiovascular diseases.

Methods

We retrospectively enrolled 936 patients with cardiovascular diseases who had undergone right heart catheterization (RHC) and chest radiography and estimated PAWP by constructing a regression CNN based on the VGG16 model. We randomly categorized 80% of the data as training data (training group, n=748) and 20% as test data (test group, n=188). Moreover, we tuned the learning rate–one of the model parameters–by 5-hold cross-validation of the training group. Correlations between PAWP measured by RHC (ground truth [GT] PAWP) and PAWP derived from the regression CNN (estimated PAWP) were tested. To visualize how the regression CNN assessed the images, we created a regression activation map (RAM), a visualization technique for regression CNN.

Results

Estimated PAWP correlated significantly with GT PAWP in both the training (r=0.76, P&lt;0.001) and test group (r=0.62, P&lt;0.001). Bland-Altman plots found a mean (SEM) difference between GT and estimated PAWP of −0.23 (0.16) mm Hg in the training and −0.05 (0.41) mm Hg in the test group. The RAM showed that our regression CNN model estimated high PAWP by focusing on the cardiomegaly and pulmonary congestion. In the test group, the area under the curve (AUC) for detecting elevated PAWP (≥18 mm Hg) produced by the regression CNN model was similar to the AUC of an experienced cardiologist (0.86 vs 0.83, respectively; P=0.24).

Conclusion

This proof-of-concept study shows that regression CNN can quantitatively estimate PAWP from standard chest radiographs in cardiovascular diseases.

Funding Acknowledgement

Type of funding sources: Private company. Main funding source(s): The Bayer Academic Support

Abstract P1009: Size And Distribution Of Human Cardiac Tissue Grafts Following Transendocardial Delivery Of Committed Cardiac Progenitors In A Swine Ischemic Heart Failure Model

Introduction: iPSC-derived committed cardiac progenitor cells (CCP) have exciting potential to remuscularize infarcted myocardium; however, little is known about CCP engraftment and differentiation following injection. We hypothesized that transendocardial injection (TEI) of CCPs with an injectable cardiac fibroblast derived extracellular matrix (ECM) retention agent would result in cardiac tissue grafts in an immunosuppressed porcine ischemic heart failure (HF) model.

Methods: Coronary artery balloon-occlusion myocardial infarction was induced in Yucatan mini-swine. After 1 month, 300M CCPs with and without 50 mg ECM particles were delivered in 15 intramyocardial injections to the border zone and infarct zone using a steerable Myostar injection catheter with NOGA XP mapping. Immunosuppressed swine were sacrificed up to 2 months following treatment. Hearts were systematically sectioned and stained for human nuclear antigen (Ku80) and cardiac troponin I/T to define the area and distribution of human grafts and cardiomyocyte content.

Results: Clusters of human grafts composed of predominantly troponin positive cardiomyocytes were observed in the infarct, at the infarct border, and in adjacent healthy tissue. Overall, 21/25 (84%) of treated pigs had human cardiac tissue grafts. In the current analysis, grafts were identified in 11/12 (91.6%) and 10/13 (76.9%) of pigs in the CCP+ECM and CCP, respectively (see Figure). The observed mean graft area was 62,930 ± 40,332 μm 2 and 185,200 ± 329,080 μm 2 per pig in the CCP+ECM and CCP only groups, respectively (p=0.23).

Conclusion: In an immunosuppressed swine ischemic HF model, TEI of CCPs ± ECM yields persistent human cardiac tissue grafts composed of predominantly of cardiomyocytes in both infarcted and non-infarcted regions of the myocardium up to 2 months following treatment.

Pemafibrate Prevents Rupture of Angiotensin II-Induced Abdominal Aortic Aneurysms

Background

Abdominal aortic aneurysm (AAA) is a life-threatening disease that lacks effective preventive therapies. This study aimed to evaluate the effect of pemafibrate, a selective peroxisome proliferator-activated receptor alpha (PPARα) agonist, on AAA formation and rupture.

Methods

Experimental AAA was induced by subcutaneous angiotensin II (AngII) infusion in ApoE ^{- / -} mice for 4 weeks. Pemafibrate (0.1 mg/kg/day) was administered orally. Dihydroethidium staining was used to evaluate the reactive oxygen species (ROS).

Results

The size of the AngII-induced AAA did not differ between pemafibrate- and vehicle-treated groups. However, a decreased mortality rate due to AAA rupture was observed in pemafibrate-treated mice. Pemafibrate ameliorated AngII-induced ROS and reduced the mRNA expression of interleukin-6 and tumor necrosis factor-α in the aortic wall. Gelatin zymography analysis demonstrated significant inhibition of matrix metalloproteinase-2 activity by pemafibrate. AngII-induced ROS production in human vascular smooth muscle cells was inhibited by pre-treatment with pemafibrate and was accompanied by an increase in catalase activity. Small interfering RNA-mediated knockdown of catalase or PPARα significantly attenuated the anti-oxidative effect of pemafibrate.

Conclusion

Pemafibrate prevented AAA rupture in a murine model, concomitant with reduced ROS, inflammation, and extracellular matrix degradation in the aortic wall. The protective effect against AAA rupture was partly mediated by the anti-oxidative effect of catalase induced by pemafibrate in the smooth muscle cells.

Magnetic Field Annihilation in a Magnetotail Electron Diffusion Region With Electron-Scale Magnetic Island

We present observations in Earth's magnetotail by the Magnetospheric Multiscale spacecraft that are consistent with magnetic field annihilation, rather than magnetic topology change, causing fast magnetic-to-electron energy conversion in an electron-scale current sheet. Multi-spacecraft analysis for the magnetic field reconstruction shows that an electron-scale magnetic island was embedded in the observed electron diffusion region (EDR), suggesting an elongated shape of the EDR. Evidence for the annihilation was revealed in the form of the island growing at a rate much lower than expected for the standard X-type geometry of the EDR, which indicates that magnetic flux injected into the EDR was not ejected from the X-point or accumulated in the island, but was dissipated in the EDR. This energy conversion process is in contrast to that in the standard EDR of a reconnecting current sheet where the energy of antiparallel magnetic fields is mostly converted to electron bulk-flow energy. Fully kinetic simulation also demonstrates that an elongated EDR is subject to the formation of electron-scale magnetic islands in which fast but transient annihilation can occur. Consistent with the observations and simulation, theoretical analysis shows that fast magnetic diffusion can occur in an elongated EDR in the presence of nongyrotropic electron effects. We suggest that the annihilation in elongated EDRs may contribute to the dissipation of magnetic energy in a turbulent collisionless plasma.

Overview of the 86th Annual Scientific Meeting of the Japanese Circulation Society - Cardiology Spreading Its Wings

The 86^thAnnual Scientific Meeting of the Japanese Circulation Society was held in a web-based format on March 11-13, 2022. In accordance with the internationalization policy of the JCS, the meeting was held with the Asian Pacific Society of Cardiology Congress 2022. The main theme was "Cardiology Spreading its Wings". The number of patients with heart failure and other cardiovascular diseases is increasing dramatically, and the fields dealt with by cardiovascular medicine are also greatly expanding. This conference was both intellectually satisfying and exciting for all participants, who numbered over 14,900. The meeting was completed with great success, and the enormous amount of cooperation and support from all involved was greatly appreciated.

Evaluation of risk factors for chemotherapy-induced nausea and vomiting in cisplatin and gemcitabine treatment for biliary tract cancer: acid suppressants do not prevent nausea

Chemotherapy-induced nausea and vomiting (CINV) is one of the most serious adverse effects of cancer therapy. Cancer patients frequently use acid suppressants (AS) for palliation of gastrointestinal symptoms associated with malignancy and/or anticancer therapy. AS are suggested as an additional option for CINV management in several antiemetic guidelines, although their efficacy remains unknown. The aim of this study was to determine whether AS administration affects CINV incidence in cisplatin and gemcitabine treatment for biliary tract cancer. The primary endpoint was to evaluate whether AS administration was associated with the incidence of all-grade nausea in the first administration by logistic analysis. The secondary endpoints were to assess factors associated with anorexia. Prophylactic antiemetics were based on current guidelines. Nausea occurred in 34.2% of patients (grade 1, 31.7%; grade 2, 2.5%). Patients exhibiting vomiting and anorexia represented 4.2% and 39.1%, respectively, without grade 3/4 symptoms. Multivariate analysis suggested that the independent risk factors for nausea as female sex, and no- or less-alcohol drinking habit and regular narcotics administration were associated with anorexia. In contrast, AS administration was not associated with nausea and anorexia incidence (odds ratio, 95% confidence interval: 1.43, 0.64-3.23; P =0.38 for nausea, 1.62, 0.71-3.68; P =0.25 for anorexia). In conclusion, we found that AS administration is not associated with CINV incidence, and female sex is a risk factor for nausea, and non-alcohol drinking habits and regular narcotic use are factors associated with anorexia in cisplatin and gemcitabine treatment for biliary tract cancer. We should correctly administer AS depending on the patient's situation. Successful CINV management needs effective monitoring and administration of prophylactic antiemetics and counter-measure medicines for patients at risk.

Impact of shear wave dispersion slope analysis for assessing the severity of myocarditis

This study aimed to elucidate the utility of a novel ultrasound-based technique, shear wave dispersion slope (SWDS) analysis, which estimates tissue viscosity, for evaluating the severity of myocardial inflammation. Experimental autoimmune myocarditis (EAM) at different disease phases [3-week (acute phase): n = 10, 5-week (subacute phase): n = 9, and 7-week (late phase): n = 11] were developed in male Lewis rats. SWDS was measured in the right and the left ventricular free walls (RVFW and LVFW) under a retrograde perfusion condition. Histological myocardial inflammation was evaluated by CD68 staining. The accumulation of CD68-positive cells was severe in the myocardium of the EAM 3-week group. The median (interquartile range) SWDS of RVFW was significantly higher in the EAM 3-week group [9.9 (6.5-11.0) m/s/kHz] than in the control group [5.4 (4.5-6.8) m/s/kHz] (P = 0.034). The median SWDS of LVFW was also significantly higher in the EAM 3-week group [8.1 (6.4-11.0) m/s/kHz] than in the control group [4.4 (4.2-4.8) m/s/kHz] (P = 0.003). SWDS and the percentage of CD68-positive area showed a significant correlation in RVFW (R2 = 0.64, P < 0.001) and LVFW (R2 = 0.73, P < 0.001). This study showed that SWDS was elevated in ventricular walls with acute inflammation and also significantly correlated with the degree of myocardial inflammation. These results suggest the potential of SWDS in estimating the histological severity of acute myocarditis.

Enhancement of pacing function by HCN4 overexpression in human pluripotent stem cell-derived cardiomyocytes

Background

The number of patients with bradyarrhythmia and the number of patients with cardiac pacemakers are increasing with the aging population and the increase in the number of patients with heart diseases. Some patients in whom a cardiac pacemaker has been implanted experience problems such as pacemaker infection and inconvenience due to electromagnetic interference. We have reported that overexpression of HCN channels producing a pacemaker current in mouse embryonic stem cell-derived cardiomyocytes showed enhanced pacing function in vitro and in vivo. The aim of this study was to determine whether HCN4 overexpression in human induced pluripotent stem cell-derived cardiomyocytes (iPSC-CMs) can strengthen the pacing function of the cells.

Methods

Human HCN4 was transduced in the AAVS1 locus of human induced pluripotent stem cells by nucleofection and HCN4-overexpressing iPSC-CMs were generated. Gene expression profiles, frequencies of spontaneous contraction and pacing abilities of HCN4-overexpressing and non-overexpressing iPSC-CMs in vitro were compared.

Results

HCN4-overexpressing iPSC-CMs showed higher spontaneous contraction rates than those of non-overexpressing iPSC-CMs. They responded to an HCN channel blocker and β adrenergic stimulation. The pacing rates against parent iPSC line-derived cardiomyocytes were also higher in HCN4-overexpressing iPSC-CMs than in non-overexpressing iPSC-CMs.

Conclusions

Overexpression of HCN4 showed enhancement of I_f current, spontaneous firing and pacing function in iPSC-CMs. These data suggest this transgenic cell line may be useful as a cardiac pacemaker.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13287-022-02818-y.

Impact of perioperative interruption of antithrombotic therapy on thrombotic and bleeding events in non-cardiac surgery

Funding Acknowledgements

Type of funding sources: None.

Introduction

Antithrombotic therapy including antiplatelet agents and anticoagulants are prescribed for secondary prevention in patients with established cardiovascular disease. Although antithrombotic therapy is often interrupted before non-cardiac surgery with or without perioperative bridging anticoagulation, the impact on thrombotic and bleeding events remains uncertain. 

Purpose

The aim of this study was to clarify the impact of perioperative interruption of anticoagulants on thrombotic and bleeding events in patients with established CVD undergoing elective non-cardiac surgery. 

Methods

A total of 330 patients chronically treated with antithrombotic therapy for secondary prevention underwent elective non-cardiac surgery under general anesthesia, with the complete interruption of antithrombotic agents. The study endpoints included all-cause death, thrombotic events, and major bleeding complications after surgical procedures. 

Results

Of 330 patients, 171 (51.8%) and 159 (48.2%) received antiplatelet agents and anticoagulants perioperatively. Atrial fibrillation (31.8%) and coronary artery disease (20.3%) were the major indications for antithrombotic regimens. Antithrombotic therapy was interrupted from 5 [2, 7] days before the surgery to 4 [2, 7] days postoperatively. Perioperative bridging therapy with unfractionated heparin was employed in 99 (30.0%) patients. During the hospitalization, 3 (0.9%) patients died due to non-cardiovascular causes. Thrombotic events and major bleeding occurred in 2 (0.6%) and 9 (2.7%) patients. Bridging therapy with heparin was non-significantly associated with an increased risk of bleeding events (5.1% vs. 1.7%, p = 0.09). In univariable and multivariable analyses, pre-operative hemoglobin level and operative duration were significantly associated with bleeding complications.

Conclusions

In the present study, complete interruption of antithrombotic therapy resulted in a few thrombotic events with a numerically higher rate of bleeding events in patients undergoing elective non-cardiac surgery. Pre-operative hemoglobin level and operative duration were significantly associated with post-operative bleeding complications.

Association between Inflammation and Functional Outcome in Patients with Sarcopenic Dysphagia

OBJECTIVES

This study aimed to investigate whether inflammation affects the outcome of swallowing ability to improve treatment for sarcopenic dysphagia.

DESIGN

A retrospective observational cohort study was performed using data from the Japanese sarcopenic dysphagia database.

SETTING

The database was constructed using data from 19 hospitals and one home visiting rehabilitation team.

PARTICIPANTS

Patients with sarcopenic dysphagia with measurements of C-reactive protein (CRP) and serum albumin (Alb) were included.

MEASUREMENTS

Patients were assigned to two groups using CRP, Alb, and the Japanese modified Glasgow Prognostic Score (mGPS). The Food Intake LEVEL Scale (FILS) was measured at the times of admission and follow-up (FILS follow-up) to assess swallowing function.

RESULTS

A total of 197 patients were included. Mean or median values of each parameter were as follows: age: 83.8±8.7, Alb: 3.2 ± 0.6 g/dL, CRP: 8.0 [3.0, 29.0] mg/L, mGPS: 1 [1-2], FILS: 7 [6-8], FILS follow-up: 8 [7-8], and duration of follow-up: 57.0 [27.0, 85.0] days. The FILS score at follow-up was significantly lower in the high CRP group (≥ 5.0 mg/L) than in the low CRP group (< 5.0 mg/L) (p = 0.01). Further, the FILS score at follow-up was significantly lower in the high mGPS group (class; 2) than in the low mGPS group (class; 0 and 1) (p = 0.03). In the multiple linear regression analyses without FILS at baseline, CRP and mGPS were independent risk factors for FILS follow-up. When FILS at baseline was entered, CRP and mGPS were not an independent risk factors for FILS follow-up.

CONCLUSIONS

Inflammation could modify the outcome of the patients with sarcopenic dysphagia. Inflammation may be an important risk factor in evaluating patients with sarcopenic dysphagia.

Efficacy of shear wave elasticity for evaluating myocardial hypertrophy in hypertensive rats

Shear wave (SW) imaging is a novel ultrasound-based technique for assessing tissue characteristics. SW elasticity may be useful to assess the severity of hypertensive left ventricular (LV) hypertrophy. This study aimed to evaluate the efficacy of SW elasticity for assessing the degree of myocardial hypertrophy using hypertensive rats. Rats were divided into hypertension group and control group. SW elasticity was measured on the excised heart. Myocardial hypertrophy was assessed histologically. LV weight was greater in hypertension group. An increase in interventricular septum and LV free wall thicknesses was observed in hypertension group. SW elasticity was significantly higher in hypertension group than in control group (14.6 ± 4.3 kPa vs. 6.5 ± 1.1 kPa, P < 0.01). The cross-sectional area of cardiomyocytes was larger in hypertension group than in control group (397 ± 50 μm2 vs. 243 ± 14 μm2, P < 0.01), and SW elasticity was positively correlated with the cross-sectional area of cardiomyocytes (R = 0.96, P < 0.01). This study showed that SW elasticity was higher in hypertensive rats and was closely correlated with the degree of myocardial hypertrophy, suggesting the efficacy of SW elasticity for estimating the severity of hypertensive LV hypertrophy.

Validation of the HFA-PEFF and the H2FPEF scores for the diagnosis of heart failure with preserved ejection fraction in Japanese patients:a report from the Japanese multicentre registry

Background

The standard diagnosis of heart failure (HF) with preserved ejection fraction (HFpEF) is based on the following: 1) symptoms of HF, 2) preserved left ventricular (LV) ejection fraction (LVEF, &gt;50%), and 3) presence of LV diastolic dysfunction confirmed by echocardiography or cardiac catheterisation. However, there are limits to the diagnostic accuracy of individual parameters, and what cut-off values should be applied and how they should be combined remain unclear. Diagnostic algorithms for HFpEF such as the HFA-PEFF algorithm and the H2FPEF score have been proposed; however, previous validation studies were conducted in stable chronic HF and did not include an invasive haemodynamic assessment. Thus, the diagnostic accuracy for HFpEF lacked robustness. Moreover, information on their applicability in the Asian population is limited.

Purpose

The aim of this study was to investigate these scores' diagnostic validity for HFpEF in Japanese patients recently hospitalised due to acute decompensated HF.

Methods

We examined patients with HFpEF recently hospitalised with acute decompensated HF whose HFA-PEFF and H2FPEF scores could be calculated at discharge from a nationwide HFpEF-specific multicentre registry (HFpEF group) and control patients who underwent echocardiography to investigate the cause of dyspnoea in our hospital (Non-HFpEF group). We calculated the HFA-PEFF and the H2FPEF scores among the studied population. Receiver operating characteristic (ROC) curves and area under the curve (AUC) were computed to compare the diagnostic accuracy of these scores.

Results

The studied population included 372 consecutive patients (194 HFpEF group and 178 Non-HFpEF group; HFpEF prevalence, 52%). The HFA-PEFF score classified 155 (42%) of all patients into the high likelihood category (5–6 points) and only 19 (5%) into the low likelihood category (0–1 point). A high HFA-PEFF score could diagnose HFpEF with a high specificity of 84% and a positive predictive value (PPV) of 82%, and a low HFA-PEFF score could rule out HFpEF with a high sensitivity of 99% and a negative predictive value (NPV) of 89%. The H2FPEF score classified 86 (23%) of all patients into the high likelihood category (6–9 points) and 84 (23%) into the low likelihood category (0–1 point). HFpEF could be diagnosed with a high H2FPEF score (specificity, 97%; PPV, 94%) or ruled out with a low H2FPEF score (sensitivity, 97%; NPV, 93%). The diagnostic accuracy for the HFA-PEFF and H2FPEF scores was 0.82 (95% confidence interval [CI] 0.78–0.86) and 0.89 (95% CI 0.86–0.93), respectively, by the AUC of the ROC curve (P=0.004) (Figure 1A). In the HFA-PEFF sub-scores, the functional score showed little diagnostic value, while the morphological and biomarker scores showed moderate diagnostic value (Figure 1B).

Conclusions

The H2FPEF score may be more useful than the HFA-PEFF score in diagnosing HFpEF in Japanese patients.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): a Grant-in-Aid for Scientific Research from the Japan Society for the Promotion of Science (JSPS KAKENHI) Figure 1

Effect of endothelial nitric oxide synthase gene polymorphism on cardiovascular death and nonfatal myocardial infarction in Japanese general population

Introduction

Single nucleotide polymorphisms (SNP) of endothelial nitric oxide synthase (NOS3) have been reported to be associated with diabetes mellitus and myocardial infarction. However, few reports have prospectively investigated the effects of NOS3 SNP on cardiovascular death and nonfatal myocardial infarction.

Purpose

The purpose of this study was to investigate the impact of NOS3 SNP on cardiovascular death and the development of nonfatal myocardial infarction.

Methods

This prospective cohort study included 2,752 subjects (aged ≥40) who participated in a community based health checkup. We genotyped two SNPs within NOS3 (rs1808593, rs1799983). All subjects were prospectively followed during the median follow-up period of 15.4 years with the end point of cardiovascular death and nonfatal myocardial infarction.

Results

The homozygous G-allele (GG), heterozygous (GT), and homozygous T-allele (TT) carriers of rs1808593 were identified in 60 (2%), 706 (26%), and 1,986 (72%) subjects, respectively. Kaplan-Meier analysis demonstrated that homozygous G-allele carriers of rs1808593 had the greater risk than those without. Multivariate Cox proportional hazard regression analysis revealed that the homozygous G allele of rs1808593 was associated with cardiovascular death and the development of nonfatal myocardial infarction after adjusting for confounding risk factors.

Conclusions

NOS3 gene polymorphism could be a genetic risk factor for cardiovascular death and nonfatal myocardial infarction in the Japanese general population.

Funding Acknowledgement

Type of funding sources: None. Figure 1

Sacubitril/valsartan ameliorates doxorubicin-induced cardiomyocyte toxicity through inhibiting oxidative stress in rats

Background

Doxorubicin (DOX)-based chemotherapy induces cardiotoxicity, which is considered the main limitation of its clinical application.

Purpose

The present study investigated the potential protective effect of sacubitril/valsartan, an angiotensin receptor–neprilysin inhibitor, against DOX-induced cardiotoxicity in rats and H9c2 cells, and whether the underlying mechanism for any such protection involves its antioxidant activity.

Methods

Male Sprague-Dawley rats were randomly divided into four groups: DOX (1.5 mg/kg/day intraperitoneally for 10 days), DOX+valsartan (31 mg/kg/day by gavage from day 1 to day 18), DOX+sacubitril/valsartan (68 mg/kg/day by gavage from day 1 to day 18), and control (saline intraperitoneally for 10 days). There were 15 rats in each group. At the end of the treatment period, samples were collected and analysed. Cardiac function, tissue morphology, and reactive oxygen species (ROS) were evaluated in rats. Serum levels of Malondialdehyde (MDA) and cardiac troponin T were also measured. Mitochondrial ROS production and cell viability were evaluated in H9c2 cells.

Results

DOX-induced cardiac dysfunction was not prevented by valsartan and sacubitril/valsartan in this model. However, the serum level of cardiac troponin T on day 18 was increased in the DOX group (0.046±0.006 ng/mL, p&lt;0.01 vs. control) and significantly reduced in the DOX+sacubitril/valsartan group (0.039±0.007 ng/mL, p=0.03 vs. DOX), but not in the DOX+valsartan group (0.046±0.005 ng/mL, p=1.00 vs. DOX). Regarding the effect of sacubitril/valsartan on fibrosis in rat myocardium, Masson's trichrome staining showed increased intestinal fibrosis in the DOX group compared to that in the control group (1.35±0.07% and 0.49±0.04%, p&lt;0.01) and significantly decreased intestinal fibrosis in the DOX+sacubitril/valsartan group (1.08±0.08%), but not in the DOX+ valsartan group (1.15±0.05%) compared to that in the DOX group (p=0.01 and p=0.15, respectively). The fluorescence intensity of dihydroethidium as a measure of ROD production in left ventricle, which was increased in the DOX group (1.56±0.07), was significantly reduced in the DOX+sacubitril/valsartan group (1.44±0.05, p=0.03), but not in the DOX+valsartan group (1.29±0.06, p=1.00). On day 11, the serum MDA level, which was increased in the DOX group, was significantly reduced in the DOX+ sacubitril/valsartan group (p=0.02), but not in the DOX+ valsartan group (p=0.75). In H9c2 cells, sacubitril/valsartan reduced DOX-induced mitochondrial ROS generation by 25%, which was more marked than valsartan-induced ROS generation (p&lt;0.01 and p=0.01, respectively). Sacubitril/valsartan improved cell viability more markedly than valsartan. Thus, DOX-induced cytotoxicity in H9c2 cells was improved by sacubitril/valsartan, but not valsartan.

Conclusions

Sacubitril/valsartan protected rat hearts from DOX-induced cardiotoxicity in vivo and in vitro by decreasing oxidative stress.

Funding Acknowledgement

Type of funding sources: Private company. Main funding source(s): This work was supported by Novartis Pharma K.K.

Implantable cardioverter-defibrillator therapy after resuscitation from cardiac arrest in vasospastic angina

Background

Patients with vasospastic angina (VSA) who are resuscitated from sudden cardiac arrest (SCA) are at high risk of recurrent cardiovascular events. However, there are no recommendations for implantable cardioverter-defibrillator (ICD) therapy in the VSA and SCA patient guidelines.

Purpose

This study investigated the prognostic impact of ICD therapy on patients with VSA and SCA.

Methods

The present multi-center registry included 280 patients who were resuscitated from SCA and received ICD implantation as secondary prophylaxis. The patients were divided into two groups according to the presence of VSA. The primary endpoint was a composite of all-cause death and appropriate ICD therapy, including appropriate anti-tachycardia pacing and shock for recurrent ventricular arrhythmias.

Results

Of 280 patients, 51 (18%) had VSA. Among those without VSA, ischemic cardiomyopathy was the leading cause of SCA (38%), followed by non-ischemic cardiomyopathies and Brugada syndrome (Table 1). During the median follow-up period of 3.8 years, 23 (8%) patients died, and 72 (26%) underwent appropriate ICD therapy. The incidence of the primary endpoint was not significantly different between patients with and without VSA (24% vs 33%, p=0.19). Further, the incidence of the primary endpoint was not significantly different among the etiologies (Figure 1)

Conclusions

In a cohort of patients who underwent ICD implantation as secondary prophylaxis, long-term clinical outcomes were comparable between those with VSA and those with other cardiac diseases after SCA. The results suggest that ICD therapy may be considered in patients with VSA and those with other etiologies after resuscitation from SCA.

Funding Acknowledgement

Type of funding sources: None. Table 1. Patient characteristics and outcomesFigure 1. Incidence of the primary endpoint

Association of symptomatic gallstones and primary hyperparathyroidism: a propensity score-matched analysis

If the prevalence of primary hyperparathyroidism (PHPT) in patients with symptomatic gallstones is higher than that in the general population, PHPT screening could reveal important clinical implications. We observed that the prevalence of PHPT in these patients was higher compared to that of healthy matched controls.

Vision-Based Sensing Systems for Autonomous Driving: Centralized or Decentralized?

The perception of the surrounding circumstances is an essential task for fully autonomous driving systems, but its high computational and network loads typically impede a single host machine from taking charge of the systems. Decentralized processing is a candidate to decrease such loads; however, it has not been clear that this approach fulfills the requirements of onboard systems, including low latency and low power consumption. Embedded oriented graphics processing units (GPUs) are attracting great interest because they provide massively parallel computation capacity with lower power consumption compared to traditional GPUs. This study explored the effects of decentralized processing on autonomous driving using embedded oriented GPUs as decentralized units. We implemented a prototype system that off-loaded image-based object detection tasks onto embedded oriented GPUs to clarify the effects of decentralized processing. The results of experimental evaluation demonstrated that decentralized processing and network quantization achieved approximately 27 ms delay between the feeding of an image and the arrival of detection results to the host as well as approximately 7 W power consumption on each GPU and network load degradation in orders of magnitude. Judging from these results, we concluded that decentralized processing could be a promising approach to decrease processing latency, network load, and power consumption toward the deployment of autonomous driving systems.

Constraints on Cosmic Strings Using Data from the Third Advanced LIGO-Virgo Observing Run

We search for gravitational-wave signals produced by cosmic strings in the Advanced LIGO and Virgo full O3 dataset. Search results are presented for gravitational waves produced by cosmic string loop features such as cusps, kinks, and, for the first time, kink-kink collisions. A template-based search for short-duration transient signals does not yield a detection. We also use the stochastic gravitational-wave background energy density upper limits derived from the O3 data to constrain the cosmic string tension Gμ as a function of the number of kinks, or the number of cusps, for two cosmic string loop distribution models. Additionally, we develop and test a third model that interpolates between these two models. Our results improve upon the previous LIGO-Virgo constraints on Gμ by 1 to 2 orders of magnitude depending on the model that is tested. In particular, for the one-loop distribution model, we set the most competitive constraints to date: Gμ≲4×10^{-15}. In the case of cosmic strings formed at the end of inflation in the context of grand unified theories, these results challenge simple inflationary models.

Constraints on Cosmic Strings Using Data from the Third Advanced LIGO-Virgo Observing Run

We search for gravitational-wave signals produced by cosmic strings in the Advanced LIGO and Virgo full O3 dataset. Search results are presented for gravitational waves produced by cosmic string loop features such as cusps, kinks, and, for the first time, kink-kink collisions. A template-based search for short-duration transient signals does not yield a detection. We also use the stochastic gravitational-wave background energy density upper limits derived from the O3 data to constrain the cosmic string tension Gμ as a function of the number of kinks, or the number of cusps, for two cosmic string loop distribution models. Additionally, we develop and test a third model that interpolates between these two models. Our results improve upon the previous LIGO-Virgo constraints on Gμ by 1 to 2 orders of magnitude depending on the model that is tested. In particular, for the one-loop distribution model, we set the most competitive constraints to date: Gμ≲4×10^{-15}. In the case of cosmic strings formed at the end of inflation in the context of grand unified theories, these results challenge simple inflationary models.

Prognosis of paradoxical low-flow low-gradient aortic stenosis after transcatheter aortic valve replacement

AIMS

In paradoxical low-flow low-gradient severe aortic stenosis (PLFLG AS) patients, stroke volume index (SVI) is reduced despite preserved left ventricular ejection fraction (LVEF). Although reduced SVI is already known as a poor prognostic predictor, the outcomes of PLFLG AS patients after transcatheter aortic valve replacement (TAVR) have not been clearly defined. We retrospectively investigated the post-TAVR outcomes of PLFLG AS patients in comparison with normal-flow high-gradient aortic stenosis (NFHG AS) patients.

METHODS

The current observational study included 245 patients with NFHG AS (mean transaortic pressure gradient ≥40 mmHg and LVEF ≥ 50%) and 48 patients with PLFLG AS (mean transaortic pressure gradient <40 mmHg, LVEF ≥ 50% and SVI < 35 ml/m2). The endpoints were all-cause mortality, hospitalization for valve-related symptoms or worsening congestive heart failure and New York Heart Association functional class III or IV.

RESULTS

PLFLG AS patients had a significantly higher proportion with a history of atrial fibrillation/flutter as compared with NFHG AS patients. All-cause mortality of PLFLG AS patients was worse than that of NFHG AS patients (P = 0.047). Hospitalization for valve-related symptoms or worsening congestive heart failure was more frequent in PLFLG AS patients than in NFHG AS patients (P = 0.041). New York Heart Association functional class III-IV after TAVR was more frequently observed in PLFLG AS patients (P = 0.019).

CONCLUSION

The outcomes of PLFLG AS patients were worse than those of NFHG AS patients in this study. Preexisting atrial fibrillation/flutter was frequent in PLFLG AS patients, and may affect their post-TAVR outcomes. Therefore, closer post-TAVR follow-up should be considered for these patients.

Income-based inequality in nationwide general health checkup participation in Japan

OBJECTIVE

In Japan, it is mandatory for employers to provide general health checkup opportunities to employees. Although many companies have subsidized checkups for employees' dependent family members, their participation is low. We assessed income-based inequality in the participation of employees' dependents in the general health checkup.

STUDY DESIGN

This is a cross-sectional descriptive study. Annual participation rate in general health checkup and various factors including income, age, and sex were collected and analyzed to examine the income-based inequality of participation rate in general health checkup.

METHODS

The data for the present study were sourced from the Fukuoka Branch of the Japan Health Insurance Association, a large medical insurer in Japan. We extracted data of 196,057 dependents aged 40-74 years. We conducted a multiple logistic regression analysis using participation from April 2015 to March 2016 as dependent variable and income category ranging from 1 (lowest) to 4 (highest) between April and June 2015 as independent variable (adjusted for sex and age). We computed slope index of inequality (SII) and relative index of inequality (RII) based on income category.

RESULTS

Higher the income, the more likely were dependents to participate in the general health checkup. SII for the participation rate of general health checkup ranged between -0.02 (95% confidence interval [CI]: -0.07 to 0.03) and 0.06 (0.03-0.09) for men; 0.03 (0.01-0.06) and 0.10 (0.09-0.11) for women. RII for the participation rate of general health checkup ranged between -0.19 (95% CI: -0.66 to 0.29) and 0.88 (0.15-1.61) for men; 0.22 (0.05-0.39) and 0.68 (0.60-0.76) for women. The highest inequality existed for men in their 50s and 60s and women in their 50s; the lowest inequality was among men and women aged 70-74 years.

CONCLUSION

There was income-based inequality in participation in the general health checkup among dependents (family members) of the insured persons. The degree of inequality differed with age group. It cannot be explained solely by financial barrier among low-income group, rather it may reflect Japanese unique context in medical insurance system.

Prenylflavonoids isolated from Macaranga tanarius stimulate odontoblast differentiation of human dental pulp stem cells and tooth root formation via the mitogen-activated protein kinase and protein kinase B pathways

AIM

To identify odontogenesis-promoting compounds and examine the molecular mechanism underlying enhanced odontoblast differentiation and tooth formation.

METHODOLOGY

Five different nymphaeols, nymphaeol B (NB), isonymphaeol B (INB), nymphaeol A (NA), 3'-geranyl-naringenin (GN) and nymphaeol C (NC) were isolated from the fruit of Macaranga tanarius. The cytotoxic effect of nymphaeols on human DPSCs was observed using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The effect of nymphaeols on odontoblast differentiation was analysed with Alizarin Red S staining and odontoblast marker expression was assessed using real-time polymerase chain reaction and Western blot analysis. The molecular mechanism was investigated with Western blot analysis. In order to examine the effect of INB on dentine formation in the developing tooth germ, INB-soaked beads were placed under the tooth bud explants in the collagen gel; thereafter, the tooth bud explant-bead complexes were implanted into the sub-renal capsules for 3 weeks. Tooth root formation was analysed using micro-computed tomography and histological analysis. Data are presented as mean ± standard error (SEM) values of three independent experiments, and results are compared using a two-tailed Student's t-test. The data were considered to have statistical significance when the P-value was less than 0.05.

RESULTS

Three of the compounds, NB, INB, and GN, did not exert a cytotoxic effect on human DPSCs. However, INB was most effective in promoting the deposition of calcium minerals in vitro (P < 0.001) and induced the expression of odontogenic marker genes (P < 0.05). Moreover, this compound strongly induced the phosphorylation of mitogen-activated protein (MAP) kinases and protein kinase B (AKT) (P < 0.05). The inhibition of p38 MAP, c-Jun N-terminal kinase (JNK), and AKT substantially suppressed the INB-induced odontoblast differentiation (P < 0.001). In addition, isonymphaeol B significantly induced the formation of dentine and elongation of the tooth root in vivo (P < 0.05).

CONCLUSIONS

Prenylflavonoids, including INB, exerted stimulatory effects on odontoblast differentiation and tooth root and dentine formation via the MAP kinase and AKT signalling pathways. These results suggest that nymphaeols could stimulate the repair processes for dentine defects or injuries.

Serum cytokine profiling in neonates with hypoxic ischemic encephalopathy

BACKGROUND

The fetal brain is vulnerable to severe and sustained hypoxia during and after birth, which can lead to hypoxic-ischemic encephalopathy (HIE). HIE is characterized by clinical and laboratory evidence of acute or subacute brain injury. The role of cytokines in the pathogenesis of brain injury and their relation to neurological outcomes of asphyxiated neonates are not fully understood. In this study, we investigated cytokine profile related to cerebral palsy (CP) with neonatal hypoxic ischemic encephalopathy (HIE) and HIE severity.

METHODS

Eligible subjects were HIE newborns with a gestational age between 36 and 42 weeks. We included newborns who was born at our NICU and did not admit to NICU as healthy controls. The study comprised 52 newborns, including 13 with mild to severe HIE and 39 healthy control. Serum cytokine profiles were performed using a LUMINEX cytokine kit (R&D Systems).

RESULTS

VEGF, MCP-1, IL-15, IL-12p70, IL-12p40, IL-1Ra, IL-2, IL-6, IL-7, IL-8, IL-10, IFN-γ, G-CSF and eotaxin in the HIE patients were significantly increased compared with the healthy neonates. In the subgroup analysis, IL-6 and G-CSF were significantly increased in CP infants (n = 5) compared with non-CP infants (n = 8). Five and eight HIE patients were classified into the mild HIE and moderate-severe HIE groups, respectively. IL-6, 10, 1Ra, and G-CSF in the moderate-severe HIE group were significantly higher than those in the mild HIE group.

CONCLUSION

We demonstrated that higher serum IL-6 and G-CSF at birth in HIE patients were associated with CP and moderate-severe HIE.

The accuracy of fine needle aspiration cytology in the clinical diagnosis of minor salivary gland tumours

The objective of this study was to investigate the accuracy of fine needle aspiration cytology (FNAC) and biopsy for the clinical diagnosis of minor salivary gland tumours (MSGTs). This retrospective study of 32 MSGT cases was conducted over a 5-year period. Clinical features including age, sex, and location of the tumour were obtained from the patient clinical records. All cases were also assessed histologically according to the 2017 World Health Organization Classification of Head and Neck Tumours. The results of FNAC and biopsy were correlated with those of histopathology, and their sensitivity, specificity, and diagnostic efficacy were calculated using histopathology as the gold standard. Eighteen malignant MSGTs (56.3%) and 14 benign MSGTs (43.8%) were diagnosed by pathological diagnosis. The most common malignant tumour was mucoepidermoid carcinoma (seven cases, 38.9%). Most benign cases were pleomorphic adenomas (13 cases, 92.9%). FNAC was performed for 23 cases and biopsy for 13 cases. The sensitivity and specificity of FNAC were 66.7% and 91.0%, respectively, while those of biopsy were 90.0% and 100.0%, respectively. Although FNAC is a minimally invasive and cost-effective procedure, it is less accurate than biopsy in the assessment of MSGTs. Repeated FNAC or biopsy should be considered in negative and unsatisfactory FNAC cases.

The Prognosis of Elderly Patients with Aortic Stenosis after Transcatheter Aortic Valve Replacement

Objective Aortic stenosis (AS) is common among elderly patients. Since transcatheter aortic valve replacement (TAVR) is a less invasive procedure than surgical aortic valve replacement for symptomatic severe AS, super-elderly patients have tended to undergo TAVR. We retrospectively investigated the post-TAVR outcome in super-elderly patients with severe AS. Methods This analysis included 433 patients who underwent TAVR in the University of Wisconsin Hospital and Clinics from 2012 to 2017. Post-TAVR mortality, complications in-hospital, rehospitalization, the New York Heart Association (NYHA) functional class and echocardiographic parameters were compared between patients <85 years old (n = 290) and ≥85 years old (n = 143). Results The patients ≥85 years old less frequently had a history of coronary artery disease (73.1% vs. 62.2%, p=0.026) and hypertension (87.2% vs. 77.6%, p=0.012) than younger patients. Furthermore, the patients ≥85 years old had moderate-severe mitral regurgitation more frequently (19.3% vs. 28.7%, p=0.037) at baseline than younger patients. There was no significant difference in in-hospital outcomes between the age groups. The 30-day mortality was worse in patients ≥85 years old than in younger ones (0.7% vs. 3.5%, p=0.042). While there was no significant difference in the long-term mortality between the 2 groups, the estimated 1-year mortality from Kaplan-Meier curves were 9.6% in patients <85 years old and 14.9% in patients ≥85 years old. The rate of in-hospital complications, rehospitalization rate, improvement in the NYHA functional class and echocardiographic parameters were comparable between the two groups. Conclusion The outcomes of super-elderly patients after TAVR were acceptable, suggesting that these patients could benefit from TAVR.

Renal arteriolar hyalinosis, not intimal thickening in large arteries, is associated with cardiovascular events in people with biopsy-proven diabetic nephropathy

AIMS

Diabetic nephropathy, a pathologically diagnosed microvascular complication of diabetes, is a strong risk factor for cardiovascular events, which mainly involve arteries larger than those affected in diabetic nephropathy. However, the association between diabetic nephropathy pathological findings and cardiovascular events has not been well studied. We aimed to investigate whether the pathological findings in diabetic nephropathy are closely associated with cardiovascular event development.

METHODS

This retrospective cohort study analysed 377 people with type 2 diabetes and biopsy-proven diabetic nephropathy, with a median follow-up of 5.9 years (interquartile range 2.0 to 13.5). We investigated how cardiovascular events were impacted by two vascular diabetic nephropathy lesions, namely arteriolar hyalinosis and arterial intimal thickening, and by glomerular and interstitial lesions.

RESULTS

Of the 377 people with diabetic nephropathy, 331 (88%) and 295 (78%) had arteriolar hyalinosis and arterial intimal thickening, respectively. During the entire follow-up period, those with arteriolar hyalinosis had higher cardiovascular event rates in the crude Kaplan-Meier analysis than those without these lesions (P = 0.005, log-rank test). When fully adjusted for clinically relevant confounders, arteriolar hyalinosis independently predicted cardiovascular events [hazard ratio (HR) 1.99; 95% confidence interval (CI) 1.12, 3.86], but we did not find any relationship between arterial intimal thickening and cardiovascular events (HR 0.89; 95% CI 0.60, 1.37). Additionally, neither glomerular nor interstitial lesions were independently associated with cardiovascular events in the fully adjusted model.

CONCLUSIONS

Arteriolar hyalinosis, but not intimal thickening of large arteries, was strongly associated with cardiovascular events in people with diabetic nephropathy.

Greater coronary lipid core plaque assessed by near-infrared spectroscopy intravascular ultrasound in patients with elevated xanthine oxidoreductase: a mechanistic insight

Background

Elevated serum uric acid level was reportedly associated with greater coronary lipid plaque. Xanthine oxidoreductase (XOR) is a rate-limiting enzyme in purine metabolism and believed to play important roles in coronary atherosclerosis. However, the relation of XOR to coronary lipid plaque and its mechanism are unclear.

Purpose

The aim of this study was to assess the impact of XOR on coronary lipid plaque and the associated factors with XOR in coronary artery disease (CAD).

Methods

Patients with stable CAD undergoing elective percutaneous coronary intervention under near-infrared spectroscopy intravascular ultrasound (NIRS-IVUS) guidance were prospectively enrolled. They were divided into three groups according to serum XOR activities; low, normal, and high. Coronary lipid core plaques in non-target vessels were evaluated by NIRS-IVUS with lipid core burden index (LCBI) and a maximum LCBI in 4 mm (maxLCBI4mm). Systemic endothelial function and inflammation were assessed with reactive hyperemia index (RHI) and high-sensitivity C-reactive protein, neutrophil-to-lymphocyte ratio, and platelet-to-lymphocyte ratio.

Results

Of 68 patients, 26, 31, and 11 were classified as low, normal, and high XOR activity groups. LCBI (474.4±171.6 vs. 347.4±181.6 vs. 294.0±155.9, p=0.04) and maxLCBI4mm (102.1±56.5 vs. 65.6±48.5 vs. 55.6±37.8, p=0.04) were significantly higher in high XOR group than in normal and low XOR groups. Although RHI was significantly correlated with body mass index, diabetes, current smoking, and high-density lipoprotein cholesterol, no relation was found between XOR activity and RHI (Figure). There were also no relations between XOR activity and high-sensitivity C-reactive protein, neutrophil-to-lymphocyte ratio, or platelet-to-lymphocyte ratio (Figure).

Conclusion

Elevated XOR activity was associated with greater coronary lipid plaque in patients with stable CAD, without significant relations to systemic endothelial function and inflammation.

Funding Acknowledgement

Type of funding source: None