Crystal structure of the GH-46 subclass III chitosanase from Bacillus circulans MH-K1 in complex with chitotetraose

BACKGROUND

Chitosanases (EC 3.2.1.132) hydrolyze chitosan which is a polymer of glucosamine (GlcN) linked by β - 1,4 bonds, and show cleavage specificity against partially acetylated chitosan containing N-acetylglucosamine (GlcNAc) residues. Chitosanases' structural underpinnings for cleavage specificity and the conformational switch from open to closed structures are still a mystery.

METHODS

The GH-46 subclass III chitosanase from Bacillus circulans MH-K1 (MH-K1 chitosanase), which also catalyzes the hydrolysis of GlcN-GlcNAc bonds in addition to GlcN-GlcN, has had its chitotetraose [(GlcN)4]-complexed crystal structure solved at 1.35 Å resolution.

RESULTS

The MH-K1 chitosanase's (GlcN)4-bound structure has numerous structural similarities to other GH-46 chitosanases in terms of substrate binding and catalytic processes. However, subsite -1, which is absolutely specific for GlcN, seems to characterize the structure of a subclass III chitosanase due to its distinctive length and angle of a flexible loop. According to a comparison of the (GlcN)4-bound and apo-form structures, the particular binding of a GlcN residue at subsite -2 through Asp77 causes the backbone helix to kink, which causes the upper- and lower-domains to approach closely when binding a substrate.

CONCLUSIONS

Although GH-46 chitosanases vary in the finer details of the subsites defining cleavage specificity, they share similar structural characteristics in substrate-binding, catalytic processes, and potentially in conformational change.

GENERAL SIGNIFICANCE

The precise binding of a GlcN residue to the -2 subsite is essential for the conformational shift that occurs in all GH-46 chitosanases, as shown by the crystal structures of the apo- and substrate-bound forms of MH-K1 chitosanase.

Olfactory and taste dysfunctions caused by COVID-19: a nationwide study

BACKGROUND

Olfactory dysfunctions (OD) and taste dysfunctions (TD) are widely recognized as characteristic symptoms of COVID-19; however, the frequency and mode of occurrence has varied depending on the viral mutation. The prevalence and characteristics of OD/TD in Japan have not been definitively investigated. The purpose of this study is to assess the prevalence of OD/TD in Japan during the Alpha variant epidemic, and measure symptom prolongation at 6 months and 1 year later following initial infection.

METHODS

Patients treated for COVID-19 between February to May 2021 were evaluated for OD/TD symptoms and provided with a QOL questionnaire. Olfactory tests and taste tests were performed using Open Essence and Taste Strips, respectively.

RESULTS

Among the 251 COVID-19 patients who participated, 119 underwent both olfactory and taste tests. Prevalence of subjective OD and TD at the time of survey was 57.8% and 40.2%, respectively. After 12 months, the prevalence fell to 5.8% for OD and 3.5% for TD. Among the OD/TD patients, 36.6% experienced parosmia, and 55.4% experienced parageusia. Prevalence of parosmia and parageusia was higher at 6 and 12 months than at the time of survey. Patients with long-lasting disease reported qualitative dysfunctions and scored significantly higher in food-related QOL problems. Most patients who were aware of their hyposmia had low scores on the olfactory test (83.1%). In contrast, only 26.7% of patients who were aware of their hypogeusia had low scores on the taste test.

CONCLUSIONS

The prevalence of COVID-19-related OD and TD at the time of survey was 57.8% and 40.2%, respectively. Subjective symptoms of OD and TD persisted for one year in 5.8% and 3.5% of patients, respectively. More than half of the patients with OD or TD complained of qualitative dysfunction and a decrease in their QOL related to eating and drinking. Most patients with TD did not have true TD, but rather developed flavour disorders associated with OD. This conclusion is supported by the finding that patients with subjective OD had low scores on the olfactory test, whereas most patients with subjective TD had normal scores on the taste test.

Percutaneous shunt vessel embolisation with Amplatzer vascular plugs II and IV in the treatment of dogs with splenophrenic shunts: four cases (2019-2022)

OBJECTIVES

To describe the treatment of four dogs with splenophrenic shunts using percutaneous shunting vessel embolisation with Amplatzer vascular plugs II and IV and provide information on their clinical outcomes.

MATERIALS AND METHODS

Dogs with splenophrenic shunts treated at a veterinary hospital from January 2019 to December 2022 were identified through a medical record search.

RESULTS

Six dogs with splenophrenic shunts were identified. Two dogs were excluded because they were treated with laparoscopic surgery. Four underwent percutaneous shunting vessel embolization with Amplatzer vascular plugs and were included in the case series. A sheath was placed in the left external jugular vein and a balloon catheter was advanced to the shunting vessel under fluoroscopy. Portal vein pressure was confirmed to be within an acceptable range during temporary balloon occlusion. Based on preoperative CT angiography and intraoperative contrast examination, Amplatzer vascular plugs II were selected for two dogs and IV were selected for two dogs. Under fluoroscopy, the plug was deployed into the shunting vessel, and angiography confirmed occlusion. In all cases, the increase in portal pressure after temporary occlusion was within the acceptable range, and complete occlusion of blood flow was possible with a single plug. There were no major procedure-related complications. No dogs developed post-ligation seizures or signs of portal hypertension. In addition, improvements in ammonia values were observed in all cases.

CLINICAL SIGNIFICANCE

Percutaneous splenophrenic shunt embolisation using Amplatzer vascular plugs II and IV is technically feasible in dogs, and assessed by intra-procedure angiography, a single plug completely obstructed blood flow in all dogs. Based on the literature search, this is the first report describing Amplatzer vascular plugs for the treatment of splenophrenic shunts.

Surface Properties of Resin Composites and CAD/CAM Blocks After Simulated Toothbrushing

OBJECTIVES

This study aimed to evaluate the surface gloss, surface roughness, and color change of restorative materials after a three-body wear abrasion.

METHODS AND MATERIALS

Four resin composites with different filler particle size (Gracefil Flo [GFF, 0.7 μm], Gracefil LoFlo [GFL, 0.25 μm], Gracefil ZeroFlo [GFZ, 0.15 μm], and Gracefil Putty [GFP, 0.3 μm]), two CAD/CAM resin composite blocks with different filler particle size (Cerasmart 300 [CS3, 0.7 μm] and Cerasmart Prime [CSP, 0.3 μm], GC), and one CAD/CAM lithium disilicate glass-ceramic block (Initial LiSi Block [ILS], GC) as a control were evaluated. Twenty slab-shaped specimens were obtained from each material. Ten specimens were subjected to 80,000 toothbrushing strokes and measured for surface gloss (Gloss Unit, GU), surface roughness (Ra, μm), and color (L*, a*, and b* values) before toothbrushing and at every 20,000 strokes. Color differences (ΔL*, Δa*, Δb*, and ΔE00) before and after toothbrushing were calculated. After 80,000 strokes, abraded surfaces were observed using scanning electron microscopy. The other 10 specimens were measured for Vickers microhardness (VHN).

RESULTS

After 80,000 toothbrushing strokes, the mean GU ranged from 60.43 to 16.12 (the highest for ILS and lowest for GFL), and the mean Ra ranged from 0.079 to 4.085 (the lowest for ILS and highest for GFL). At all measuring stages, the calculated ΔE00 values ranged from 0.31 to 0.92 for all materials. The mean VHN ranged from 632.34 to 39.08 (the highest for ILS and lowest for GFZ). The resin composite containing the largest filler particle (GFF) showed significantly lower Ra and higher VHN than other resin composites (GFL, GFZ, and GFP). The CAD/CAM resin composite block containing a smaller filler particle (CSP) retained significantly higher GU than that containing a larger filler particle (CS3). A negative correlation between GU and Ra was detected.

CONCLUSIONS

Based on the findings, toothbrush abrasion induced a decrease in GU and an increase in Ra for all resin-based materials tested. Resin-based materials with larger filler size tended to show lower Ra, while resin-based materials with smaller filler size tended to show a smaller reduction in GU. These were more pronounced for light-cure resin composites than for resin composite blocks for CAD/CAM.

Structural insight into an anti-BRIL Fab as a G-protein-coupled receptor crystallization chaperone

Structure determination of G-protein-coupled receptors (GPCRs) is key for the successful development of efficient drugs targeting GPCRs. BRIL is a thermostabilized apocytochrome b₅₆₂ (with M7W/H102I/R106L mutations) from Escherichia coli and is often used as a GPCR fusion protein for expression and crystallization. SRP2070Fab, an anti-BRIL antibody Fab fragment, has been reported to facilitate and enhance the crystallization of BRIL-fused GPCRs as a crystallization chaperone. This study was conducted to characterize the high-resolution crystal structure of the BRIL-SRP2070Fab complex. The structure of the BRIL-SRP2070Fab complex was determined at 2.1 Å resolution. This high-resolution structure elucidates the binding interaction between BRIL and SRP2070Fab. When binding to BRIL, SRP2070Fab recognizes conformational epitopes, not linear epitopes, on the surface of BRIL helices III and IV, thereby binding perpendicularly to the helices, which indicates stable binding. Additionally, the packing contacts of the BRIL-SRP2070Fab co-crystal are largely due to SRP2070Fab rather than BRIL. The accumulation of SRP2070Fab molecules by stacking is remarkable and is consistent with the finding that stacking of SRP2070Fab is predominant in known crystal structures of BRIL-fused GPCRs complexed with SRP2070Fab. These findings clarified the mechanism of SRP2070Fab as a crystallization chaperone. Moreover, these data will be useful in the structure-based drug design of membrane-protein drug targets.

Changes in cerebrovascular disease-related deaths and their location during the COVID-19 pandemic in Japan

Objective

The COVID-19 pandemic placed an enormous strain on healthcare systems and raised concerns for delays in the management of patients with acute cerebrovascular events. In this study, we investigated cerebrovascular excess deaths in Japan.

Study design

Vital mortality statistics from January 2012 to May 2022 were obtained from the Japanese Ministry of Health, Labour and Welfare.

Methods

Using quasi-Poisson regression models, we estimated the expected weekly number of cerebrovascular deaths in Japan from January 2020 through May 2022 by place of death. Estimates were calculated for deaths in all locations, as well as for deaths in hospitals, in geriatric health service facilities, and at home. The age subgroups of ≥75 and <75 years were also considered. Weeks with a statistically significant excess of cerebrovascular deaths were determined when the weekly number of observed deaths exceeded the upper bound of 97.5% prediction interval.

Results

Excess deaths were noted in June 2021 and became more pronounced from February 2022 onwards. The trend was notable among those aged ≥75 years and for those who died in hospitals. With respect to the location of deaths, the excess was significant in geriatric health services facilities from April 2020 to June 2021, while no evidence of excess hospital deaths was observed during the same period.

Conclusions

Beginning in late 2021, excess cerebrovascular deaths coincided with the spread of the Omicron variant and may be associated with increased healthcare burden. In 2020, COVID-19 altered the geography of cerebrovascular deaths, with fewer people dying in hospitals and more dying in geriatric health service facilities and at home.

In vitro pharmacological profile of KW-6356, a novel adenosine A2A receptor antagonist/inverse agonist

KW-6356 is a novel adenosine A_2A receptor (A_2A receptor) antagonist/inverse agonist, and its efficacy as monotherapy in Parkinson's disease (PD) patients has been reported. Istradefylline is a first-generation A_2A receptor antagonist approved for use as adjunct treatment to levodopa/decarboxylase inhibitor in adult PD patients experiencing OFF episodes. In this study, we investigated the in vitro pharmacological profile of KW-6356 as an A_2A receptor antagonist/inverse agonist and the mode of antagonism and compared them with istradefylline. In addition, we determined co-crystal structures of A_2A receptor in complex with KW-6356 and istradefylline to explore the structural basis of the antagonistic properties of KW-6356. Pharmacological studies have shown that KW-6356 is a potent and selective ligand for the A_2A receptor (the -log of inhibition constant = 9.93 {plus minus} 0.01 for human receptor) with a very low dissociation rate from the receptor (the dissociation kinetic rate constant = 0.016 {plus minus} 0.006 min^-1 for human receptor). In particular, in vitro functional studies indicated that KW-6356 exhibits insurmountable antagonism and inverse agonism, while istradefylline exhibits surmountable antagonism. Crystallography of KW-6356- and istradefylline-bound A_2A receptor have indicated that interactions with His250^6.52 and Trp246^6.48 are essential for the inverse agonism, while the interactions at both deep inside the orthosteric pocket and the pocket lid stabilizing the extracellular loop conformation may contribute to the insurmountable antagonism of KW-6356. These profiles may reflect important difference in vivo and help predict better clinical performance. Significance Statement KW-6356 is a potent and selective adenosine A_2A receptor antagonist/inverse agonist and exhibits insurmountable antagonism, while istradefylline, a first-generation adenosine A_2A receptor antagonist, exhibits surmountable antagonism. Structural studies of adenosine A_2A receptor in complex with KW-6356 and istradefylline explain the characteristic differences in the pharmacological properties of KW-6356 and istradefylline.

TRIM27 expression is associated with poor prognosis in sinonasal mucosal melanoma

BACKGROUND

Tripartite motif-containing 27 (TRIM27) has been implicated in the progression of various cancers. However, the role of TRIM27 in sinonasal mucosal melanoma (SNMM) remains poorly understood.

MATERIALS & METHODS

We retrospectively examined 28 patients with SNMM treated with between 2003 and 2021. We undertook immunohistochemical analysis of TRIM27, Ki-67, and p-Akt1 expression in SNMM tissues. We also investigated the relationship between TRIM27 expression and clinical characteristics, prognosis, Ki-67 as a tumor growth potential marker, and p-Akt1 as one of the prognostic factors in mucosal melanoma.

RESULTS

TRIM27 expression was significantly higher in T4 disease than in T3 disease and was higher in stage IV than in stage III. Patients with high-TRIM27 SNMM had a significantly poorer prognosis in terms of overall survival (OS) and disease-free survival.There was also a significantly higher rate of distant metastasis. Univariate analysis for OS revealed that TRIM27 and T classification were significant poor prognostic factors. In addition, the Ki-67 positive score and the p-Akt1 total staining score were significantly higher in the high-TRIM27 group than in the low-TRIM27 group.

CONCLUSIONS

High TRIM27 expression in SNMM was associated with advanced T classification, poor prognosis and distant metastasis. We suggest that TRIM27 has potential as a novel biomarker for prognosis in SNMM.

Involvement of growth differentiation factor 15 in paradoxical relationship between body mass index and mortality in patients with suspected or known coronary artery disease; The ANOX Study

Background

Obesity is a well-established risk factor for type 2 diabetes mellitus, hypertension and dyslipidemia, leading to coronary artery disease (CAD). Nevertheless, body mass index (BMI) is inversely associated with cardiovascular (CV) mortality in patients with cardiac disorders, termed “obesity paradox”. However, the underlying mechanism remains unclear.

Purpose

To clarify important factors involved in the pathogenesis of obesity paradox.

Methods

Using data from a multicenter, prospective cohort of 2,418 patients with suspected or known CAD enrolled in the ANOX study, we assessed the relationship between BMI at baseline and the incidence of CV death over 3 years, and investigated the involvement of several endocrine factors which were previously reported to have some roles in obesity and heart diseases, such as adiponectin, N-terminal pro-brain natriuretic peptide (NT-proBNP) and growth differentiation factor 15 (GDF-15), in the relationship between BMI and CV death.

Results

In Kaplan-Meier analyses, the lower quartiles of BMI and the higher quartiles of adiponectin levels were paradoxically associated with the higher cumulative incidence of CV death. To clarify the important factors involved in the paradoxical association between BMI or adiponectin and mortality, we first investigated independent determinants for BMI and adiponectin levels respectively, using multiple stepwise regression analyses among many clinical factors, and then narrow down the prognostic factors commonly associated with BMI and adiponectin, which were age, hemoglobin and NT-proBNP. Interestingly, circulating levels of GDF15 were significantly correlated with NT-proBNP levels, and the presence of anemia raised the gradient of the correlation line in a scatter plot (without anemia, r=0.139, p&lt;0.0001; with anemia, r=0.228, p&lt;0.0001). Moreover, the highest GDF15 quartile showed significantly lower BMI and higher adiponectin levels compared to the lower quartiles (p&lt;0.001 and p&lt;0.001, respectively, by Student t-test). In Cox proportional hazard models, hazard ratios (HRs) of BMI (per 1-unit increase) were 0.90 (95% confidence interval [CI], 0.85–0.96) for CV death. Additional adjustment for hemoglobin, NT-proBNP, adiponectin or GDF15 diminished the statistical significance (HR, 0.92 [95% CI, 0.87–0.99], 0.95 [0.89–1.01], 0.92 [0.87–0.99], or 0.93 [0.87–0.99], respectively).

Conclusions

The lower BMI and the higher adiponectin levels were paradoxically associated with the higher incidence of CV death in patients with CAD. This paradox may be mediated by cardiac endocrine factors induced by cardiac stresses, including GDF-15 in addition to natriuretic peptides.

Funding Acknowledgement

Type of funding sources: Public Institution(s). Main funding source(s): The ANOX study is supported by a Grant-in-Aid for Clinical Research from the National Hospital Organization.

Vascular endothelial factor C and D in patients with heart failure with preserved, mildly reduced, and reduced ejection fraction: the PREHOSP-CHF study

Background

The lymphatic system has been suggested to play an important role in cardiovascular diseases including heart failure (HF). Vascular endothelial growth factor C (VEGF-C) and D (VEGF-D) are key regulators of lymphangiogenesis, and we recently reported the association of low VEGF-C with the risk of all-cause death and high VEGF-D with the risk of HF hospitalization in patients with HF.

Purpose

To investigate the association of VEGF-C and VEGF-D with prognosis in patients with HF with preserved ejection fraction (EF) (HFpEF: EF≥50%), mildly reduced EF (HFmrEF: EF, 40–49%), and reduced EF (HFrEF: EF&lt;40%).

Methods

The PREHOSP-CHF study is a multicenter prospective cohort study to determine the predictive value of angiogenesis-related biomarkers in HF. A total of 1,024 patients (mean age 75.5±12.6 years; 58.7% male) admitted to acute decompensated HF were included in the analyses. Serum levels of VEGF-C and VEGF-D, as well as N-terminal pro B-type natriuretic peptide (NT-proBNP), high sensitivity cardiac troponin-I (hs-cTnI), high sensitivity C reactive protein, were measured at the time of discharge. Patients were followed-up over two years.

Results

The numbers of HFpEF, HFmrEF, and HFrEF were 429 (41.9%), 186 (18.2%), and 409 (39.9%), respectively. HFpEF patients were older, more likely to be female, and had more hypertension, atrial fibrillation, and anemia, but less coronary artery disease. NT-proBNP and hs-cTnI levels increased with decreasing EF. VEGF-C levels decreased with increasing EF (median [interquartile range]: HFpEF, 4508 [3318–5919] pg/ml; HFmrEF, 4719 [3663–6203] pg/ml; HFrEF, 5023 [3804–6382] pg/ml), whereas VEGF-D levels were comparable among the three EF groups (HFpEF, 404.6 [293.1–560.3] pg/ml; HFmrEF, 386.0 [298.5–556.3] pg/ml; HFrEF, 414.2 [296.1–557.3] pg/ml). In multivariate stepwise logistic regression analyses, anemia and high NT-proBNP were independently associated with low VEGF-C levels, and high NT-proBNP was independently associated with high VEGF-D levels, across all the EF groups. During the follow-up, incidences of all-cause death and HF hospitalizations were similar among the three EF groups (log-rank P=0.6 for all-cause death, and log-rank P=0.3 for HF hospitalization). On multivariate Cox proportional hazard analyses including established risk factors and cardiovascular biomarkers, VEGF-C levels tended to be inversely associated with the incidence of all-cause death in patients with HFpEF and HFrEF (Figure). On the contrary, VEGF-D levels were significantly and positively associated with the incidence of HF hospitalization in patients with HFpEF, and tended to be positively associated with it in patients with HFmrEF and HFrEF (Figure).

Conclusions

Low VEGF-C was associated with the risk of all-cause death in patients with HFpEF and HFrEF, while high VEGF-D was associated with the risk of HF hospitalization especially in HFpEF.

Funding Acknowledgement

Type of funding sources: Public Institution(s). Main funding source(s): Grant-in-Aid for Clinical Research from the National Hospital Organization

Associations of soluble fms-like tyrosine kinase-1 with cardiovascular events and stroke in patients with atrial fibrillation and suspected or known coronary artery disease: the EXCEED-J study

Background

Atrial fibrillation (AF) increases the risk of stroke. Soluble fms-like tyrosine kinase-1 (sFlt-1), a vascular endothelial growth factor (VEGF) antagonist, has been suggested as a marker of endothelial dysfunction, which are associated with both AF and coronary artery disease (CAD). Recently, we demonstrated that sFlt-1 is independently associated with major adverse cardiovascular (CV) events (MACE) in patients with suspected or known CAD. However, the prognostic utility of sFlt-1 in patients with AF remains unknown.

Methods

Using data from a multicenter, prospective cohort of 3255 patients with suspected or known CAD, we investigated whether AF modifies the prognostic utility of sFlt-1. Heparin-free serum levels of sFlt-1, N-terminal pro-brain natriuretic peptide, high-sensitivity cardiac troponin-I, high-sensitivity C-reactive protein, cystatin C, neutrophil gelatinase-associated lipocalin, VEGF, and placental growth factor were measured in 324 patients with AF and 2931 patients without AF. The primary outcome was MACE defined as a composite of CV death, nonfatal myocardial infarction, and nonfatal stroke. The secondary outcomes were all-cause death, CV death, stroke, heart failure (HF) hospitalization, and coronary/peripheral artery revascularization. The biomarkers were natural log-transformed for use as continuous variables.

Results

After adjustment for potential clinical confounders including anticoagulant drug use, sFlt-1 was significantly associated with MACE (hazard ratio for 1 standard deviation increase [HR], 1.55; 95% confidence interval [CI], 1.14–2.08), CV death (HR, 1.68; 95% CI, 1.10–2.48), and stroke (HR, 1.89; 95% CI, 1.16–3.10), but not with all-cause death (HR, 1.32; 95% CI, 0.99–1.73), HF hospitalization (HR, 0.97; 95% CI, 0.73–1.25), or revascularization (HR, 0.99; 95% CI, 0.74–1.28) in patients with AF, whereas sFlt-1 was significantly associated with MACE (HR, 1.19; 95% CI, 1.02–1.37), all-cause death (HR, 1.19; 95% CI, 1.05–1.34), CV death (HR, 1.26; 95% CI, 1.03–1.48), and HF hospitalization (HR, 1.26; 95% CI, 1.11–1.42), but not with stroke (HR, 1.06; 95% CI, 0.81–1.33) or revascularization (HR, 1.01; 95% CI, 0.95–1.07) in patients without AF. Among other biomarkers, only VEGF was significantly associated with MACE (HR, 1.55; 95% CI, 1.02–2.44), and no biomarkers were significantly associated with CV death or stroke in patients with AF. sFlt-1 added incremental prognostic information for MACE (P=0.005 for net reclassification improvement [NRI], P=0.026 for integrated discrimination improvement [IDI]) and stroke (P=0.034 for NRI, P=0.018 for IDI), but not for CV death (P=0.021 for NRI, P=0.134 for IDI), to the model with potential clinical confounders in patients with AF.

Conclusions

sFlt-1 independently predicted MACE and stroke in patients with AF and suspected or known CAD. sFlt-1 may serve as a novel prognostic biomarker to stratify the risk of MACE and stroke in patients with AF.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Health Labour Sciences Research Grant (2013-2014), AMED (2015-2017, Grant Number JP17ek0210008)

Serum amyloid A-low-density-lipoprotein complex and mortality in patients with suspected or known coronary artery disease: the ANOX study

Background

Serum amyloid A-low-density-lipoprotein (SAA-LDL) is a complex formed from the oxidative interaction between SAA and LDLs. A relatively small-scale study has shown that circulating SAA-LDL levels may serve as a prognostic marker in patients with stable coronary artery disease (CAD). However, the prognostic value of SAA-LDL should be confirmed in a larger-scale cohort study.

Methods

Using data from a multicenter, prospective cohort of 2416 patients with suspected or known CAD enrolled in the ANOX (Development of Novel Biomarkers Related to Angiogenesis or Oxidative Stress to Predict Cardiovascular Events) study, we assessed the prognostic value of serum levels of SAA-LDL. The primary outcome was all-cause death. The secondary outcomes were cardiovascular death and major adverse cardiovascular events (MACE) defined as a composite of cardiovascular death, nonfatal myocardial infarction, and nonfatal stroke. Patients were followed up over 3 years.

Results

Stepwise regression analysis including baseline data on potential clinical confounders (i.e., age, sex, body mass index, hypertension, dyslipidemia, diabetes, current smoking, estimated glomerular filtration rate, the Gensini score, previous myocardial infarction, previous stroke, previous heart failure hospitalization, atrial fibrillation, malignancies, anemia, antihypertensive drug use, statin use, and aspirin use) and established cardiovascular biomarkers (i.e., N-terminal pro-brain natriuretic peptide, high-sensitivity cardiac troponin I [hs-cTnI], and high-sensitivity C-reactive protein [hs-CRP]) revealed that independent determinants of SAA-LDL levels were female sex, dyslipidemia, the Gensini score, absence of statin use, hs-cTnI, and hs-CRP. After adjusting for potential clinical confounders and established cardiovascular biomarkers, the highest quartile of SAA-LDL levels (vs. the lowest quartile) was significantly associated with the incidence of all-cause death (hazard ratio [HR], 1.51; 95% confidence interval [CI], 1.02–2.26), but not with that of cardiovascular death (HR, 1.11; 95% CI, 0.59–2.10) or MACE (HR, 1.57; 95% CI, 0.97–2.57). Stratified analyses revealed that this association was pronounced in patients with low hs-cTnI (&lt;75th percentile) (HR, 1.85; 95% CI, 1.06–3.30) and in patients with low hs-CRP levels (≤1.0 mg/L) (HR, 2.30; 95% CI, 1.17–4.79).

Conclusions

Elevated SAA-LDL levels were independently associated with the risk of all-cause death in patients with suspected or known CAD. The SAA-LDL level appears to serve as a prognostic biomarker for risk stratification in relatively low-risk patients with low hs-cTnI (&lt;75th percentile) or low hs-CRP (≤1.0 mg/L).

Funding Acknowledgement

Type of funding sources: Public Institution(s). Main funding source(s): The ANOX study is supported by a Grant-in-Aid for Clinical Research from the National Hospital Organization.

Evaluation of the direct protective effects of Canagliflozin on the Isoproterenol-induced cell injury in rat cardiomyocytes

Background

Sodium-glucose cotransporter-2 (SGLT2) inhibitors are agents that act by inhibiting glucose and sodium reabsorption in the proximal renal tubule which promotes urinary glucose excretion. More recently, significant benefit data of SGLT2 inhibitors in patients with heart failure, independent of the presence of type 2 diabetes has been reported. We have previously demonstrated that Canagliflozin (Cana), a SGLT2 inhibitor, reduced the ventricular effective refractory period in isoproterenol (ISP)-induced myocardial injury rat model accompanied with the suppression of reactive oxygen species and the elevation of ketone bodies, suggesting the effect of Cana on electrical cardiac remodeling. The direct effect of Cana to the cardiomyocytes and its underlying molecular mechanism was remained to be clarified. We therefore established an ISP-induced neonatal rat ventricular cardiomyocyte (NRVCM) in vitro model, pretreated with Cana and/or ketone bodies.

Methods

Primary NRVCM were isolated from Wistar rats, were pretreated by Cana with or without βOHB (the most abundant ketone body in circulation), followed by a stimulation of ISP (10μM). Cells without drug or ketone body pretreatment were used as control. We then analyzed its effect on cell viability, apoptosis, and mitochondrial membrane potential using MTT assay, TUNEL assay, and mitochondrial membrane potential assay, respectively. MTT assay was also performed with or without PI3k inhibitor, LY294002. The end-labeling of DNA fragmentation were labelled with FITC, followed by the nuclei counterstain with DAPI and were observed with confocal microscope. The apoptotic index was defined as the percentage of TUNEL positive cells / total nuclei.

Results

Cana rescued the reduction of NRVCM cell viability induced by ISP stimulation for 24 hours which was inhibited by LY294002 compared to cells without pretreatment. Interestingly, pretreatment of βOHB with or without Cana improved also the NRCVM cell viability whereas there was no significant difference between these two conditions or with cells treated with Cana only, suggesting the direct protective effect of Cana. In 48 hours of ISP stimulation, the apoptotic index intends to decrease in Cana and/or βOHB compared to cells without pretreatment (Figure 1). Although the mitochondrial function was maintained in Cana-pretreated cells compared to cells without pretreatment, there was no significant difference in βOHB-pretreated cells.

Conclusions

Cana has a direct protective effect on cardiomyocytes cell viability, apoptosis as well as the mitochondrial function impaired by ISP through the cell survival signaling PI3K/Akt pathway. This brings a new insight to the therapeutic target of cardiovascular disease.

Funding Acknowledgement

Type of funding sources: None.

Post COVID-19 condition of the Omicron variant of SARS-CoV-2

Objectives

To investigate the prevalence of post coronavirus disease (COVID-19) condition of the Omicron variant in comparison to other strains.

Study design

A single-center cross-sectional study.

Methods

Patients who recovered from Omicron COVID-19 infection (Omicron group) were interviewed via telephone, and patients infected with other strains (control group) were surveyed via a self-reporting questionnaire. Data on patients’ characteristics, information regarding the acute-phase COVID-19, as well as presence and duration of COVID-19-related symptoms were obtained. Post COVID-19 condition in this study was defined as a symptom that lasted for at least 2 months, within 3 months of COVID-19 onset. We investigated and compared the prevalence of post COVID-19 condition in both groups after performing propensity score matching.

Results

We conducted interviews for 53 out of 128 patients with Omicron and obtained 502 responses in the control group. After matching cases with controls, 18 patients from both groups had improved covariate balance of the factors: older adult, female sex, obesity, and vaccination status. There were no significant differences in the prevalence of each post COVID-19 condition between the two groups. The number of patients with at least one post COVID-19 condition in the Omicron and control groups were 1 (5.6%) and 10 (55.6%) (p = 0.003), respectively.

Conclusions

The prevalence of post Omicron COVID-19 conditions was less than that of the other strains. Further research with a larger sample size is needed to investigate the precise epidemiology of post COVID-19 condition of Omicron, and its impact on health-related quality of life and social productivity.

The prognostic value of 18F-FDG PET/CT taken immediately after completion of radiotherapy for lung cancer treated with concurrent chemoradiotherapy: A pilot study

PURPOSE

The prognostic value of F-18 fluorodeoxyglucose positron emission tomography/computed tomography (PET/CT) taken immediately after completion of radiotherapy in lung cancer patients is not well known. The purpose of this study is to assess the prognostic value of PET/CT taken immediately after completion of radiotherapy in lung cancer patients.

MATERIALS AND METHODS

Patients with primary lung cancer planned to undergo concurrent chemoradiotherapy were enrolled. Patients underwent PET/CT scans at 3 time points: before radiotherapy, within 24hours of completing radiotherapy (im-PET/CT), and 2-9 months after radiotherapy (post-PET/CT). Maximum standardized uptake value (SUV_max) was obtained. A post-PET/CT-SUV_max cut-off of 2.5 was determined as radiotherapy success.

RESULTS

Nineteen patients were enrolled. im-PET/CT-SUV_max for patients in the high post-PET/CT-SUV_max group was significantly higher than that of the low group (P=0.004). Receiver operator curve analysis indicated that im-PET/CT-SUV_max of 4.35 was an optimal cut-off value to discriminate between the two groups. Multivariable analysis showed that a high im-PET/CT-SUV_max was significantly associated with a high post-PET/CT-SUV_max (P=0.003).

CONCLUSION

PET/CT-SUV_max taken immediately following radiotherapy was associated with that evaluated 2-9 months after radiotherapy.

Effects of Timing of Medium-Chain Triglycerides (8:0 and 10:0) Supplementation during the Day on Muscle Mass, Function and Cognition in Frail Elderly Adults

OBJECTIVES

Supplementation with 6 g/day of medium-chain triglycerides (MCTs) at dinnertime increases muscle function and cognition in frail elderly adults relative to supplementation with long-chain triglycerides. However, suitable timing of MCT supplementation during the day is unknown.

DESIGN

We enrolled 40 elderly nursing home residents (85.9 ± 7.7 years) in a 1.5-month randomized intervention trial. Participants were randomly allocated to two groups: one received 6 g/day of MCTs at breakfast (breakfast group) as a test group and the other at dinnertime (dinner group) as a positive control group.

MEASUREMENTS

Muscle mass, strength, function, and cognition were monitored at baseline and 1.5 months after initiation of intervention.

RESULTS

Thirty-seven participants completed the study and were included in the analysis. MCT supplementation in breakfast and dinner groups respectively increased right arm muscle area from baseline by 1.1 ± 0.8 cm2 (P<0.001) and 1.6 ± 2.5 cm2 (P<0.001), left arm muscle area by 1.1 ± 0.7 cm2 (P<0.001) and 0.9 ± 1.0 cm2 (P<0.01), right knee extension time by 39 ± 42 s (P<0.01) and 20 ± 32 s (P<0.05), leg open and close test time by 1.74 ± 2.00 n/10 s (P<0.01) and 1.67 ± 2.01 n/10 s (P<0.01), and Mini-Mental State Examination score by 1.5 ± 3.0 points (P=0.06) and 1.0 ± 2.1 points (P=0.06). These increases between two groups did not differ statistically significantly.

CONCLUSION

Supplementation with 6 g MCTs/day for 1.5 months, irrespective of ingestion at breakfast or dinnertime, could increase muscle mass and function, and cognition in frail elderly adults.

Prognostic value of machine learning for acute heart failure

Funding Acknowledgements

Type of funding sources: None.

Background

At onset of acute heart failure (AHF), various clinical fundamental parameters including vital sign, laboratory data, or initial treatment were investigated, and we can roughly estimate the prognosis. However, machine learning method for prediction of the prognosis was not studied.

Purpose

To elucidate prognostic value of machine learning for AHF comparing conventional statistical model.

Methods

We enrolled consecutive 300 patients with AHF (79.5 ± 12.1 years, 158 Males). Patients with acute coronary syndrome, mechanical circulatory support cases, and cardio-pulmonary arrest cases were excluded. The patients were randomly divided into 80% (240 cases) and 20% (60 cases), and the former was used as train data, and the latter as validation data. Objective variable was set as cardiac death in one year. First, logistic regression analysis with Akaike’s information criterion (AIC) was performed, and extracted predictive parameters. The predictive model for the cardiac prognosis was constructed by cut-off value of ROC curve analysis of propensity score was calculated. Next, machine learning (random forest method and deep learning) to build predictive model was performed with the predictors. Finally, accuracy of each predictive model was compared.

Results

Thirty cases showed cardiac death in one year. Logistic regression with AIC extracted 8  predictors, and the cut off-value of propensity score with the 6 parameters was 0.110. The accuracy was 0.714 and area under ROC (AUROC) was 0.836. Conversely, random forest method demonstrated the accuracy as 0.927, AUROC 0.860. On deep learning, the accuracy was 0.937 and AUROC 0.901. 

The top 4 high feature importance of random forest were Cl/red blood cell count/pH/Anion Gap. However, accuracy of those predictors was lower than that of machine learning.

Conclusion

Machine learning was a powerful tool to predict cardiac prognosis of AHF, comparing with conventional statistical model. Abstract Figure. Statistical model

Direct visualization of the three-dimensional shape of skyrmion strings in a noncentrosymmetric magnet

Magnetic skyrmions are topologically stable swirling spin textures that appear as particle-like objects in two-dimensional (2D) systems. Here, utilizing scalar magnetic X-ray tomography under applied magnetic fields, we report the direct visualization of the three-dimensional (3D) shape of individual skyrmion strings in the room-temperature skyrmion-hosting non-centrosymmetric compound Mn_1.4Pt_0.9Pd_0.1Sn. Through the tomographic reconstruction of the 3D distribution of the [001] magnetization component on the basis of transmission images taken at various angles, we identify a skyrmion string running through the entire thickness of the sample, as well as various defect structures, such as the interrupted and Y-shaped strings. The observed point defect may represent the Bloch point serving as an emergent magnetic monopole, as proposed theoretically. Our tomographic approach with a tunable magnetic field paves the way for direct visualization of the structural dynamics of individual skyrmion strings in 3D space, which will contribute to a better understanding of the creation, annihilation and transfer of these topological objects.

Influence of Perceived Ageism on Older Adults: Focus on Attitudes toward Young People and Life Satisfaction

The world’s population is aging, and intergenerational conflicts between older adults and young people are becoming more serious. This study focused on ageism as a cause of intergenerational conflicts and older adults’ diminished mental health status. We conducted an online survey of older Japanese participants (n = 1.096). Our results indicated that older adults who perceived more ageism directed toward them (1) had more negative attitudes toward young people and (2) had lower life satisfaction, which persisted even after controlling for variables such as old age identity and depressive tendencies. Accordingly, we suggest that ageism may reinforce intergenerational conflicts between older adults and young people and compromise older adults’ mental health status. The findings of this study can aid gerontological and psychological research aimed at reducing ageism.

Factors Associated with Increased Caregiver Burden of Informal Caregivers during the COVID-19 Pandemic in Japan

This study's objective was to explore the association between various factors and the increased caregiver burden of informal caregivers during the COVID-19 pandemic. On February, 2021, 700 informal caregivers completed an online survey. We assessed the change in caregiver burden during the COVID-19 pandemic. Among all caregiver participants, 287 (41.0%) complained of an increased caregiver burden due to the COVID-19 pandemic. The factors associated with increased caregiver burden were depressive symptoms in caregivers [odds ratio (OR), 2.20; 95% confidence interval (CI), 1.50-3.23], dementia (OR, 2.48; 95%CI, 1.07-5.73) and low Barthel Index scores (OR, 2.01; 95%CI, 1.39-2.90) in care receivers, care days (OR, 1.09; 95%CI, 1.01-1.17) and times (OR, 1.06; 95%CI, 1.01-1.10), and use of home care service (OR, 1.46; 95%CI, 1.01-2.10) and visiting care service (OR, 1.71; 95%CI, 1.20-2.45). These findings suggest we need to pay attention to the physical and mental health of both the care receivers and caregivers.

Excess deaths from COVID-19 in Japan and 47 prefectures from January through June 2021

Objectives

In Japan, several studies have reported no excess all-cause deaths (the difference between the observed and expected number of deaths) during the coronavirus disease 2019 (COVID-19) pandemic in 2020. This study aimed to estimate the weekly excess deaths in Japan's 47 prefectures for 2021 until June 27.

Study design

Vital statistical data on deaths were obtained from the Ministry of Health, Labour and Welfare of Japan. For this analysis, we used data from January 2012 to June 2021.

Methods

A quasi-Poisson regression was used to estimate the expected weekly number of deaths. Excess deaths were expressed as the range of differences between the observed and expected number of all-cause deaths and the 95% upper bound of the one-sided prediction interval.

Results

Since January 2021, excess deaths were observed for the first time in the week corresponding to April 12–18 and have continued through mid-June, with the highest excess percentage occurring in the week corresponding to May 31–June 6 (excess deaths: 1431–2587; excess percentage: 5.95–10.77%). Similarly, excess deaths were observed in consecutive weeks from April to June 2021 in 18 of 47 prefectures.

Conclusions

For the first time since February 2020, when the first COVID-19 death was reported in Japan, excess deaths possibly related to COVID-19 were observed in April 2021 in Japan, during the fourth wave. This may reflect the deaths of non-infected people owing to the disruption that the pandemic has caused.

Tea crude extracts effectively inactivate severe acute respiratory syndrome coronavirus 2

It is well known that black and green tea extracts, particularly polyphenols, have antimicrobial activity against various pathogenic microbes including viruses. However, there is limited data on the antiviral activity against severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2), which emerged rapidly in China in late 2019 and which has been responsible for coronavirus disease 2019 (COVID‐19) pandemic globally. In this study, 20 compounds and three extracts were obtained from black and green tea and found that three tea extracts showed significant antiviral activity against SARS‐CoV‐2, whereby the viral titre decreased about 5 logs TCID₅₀ per ml by 1·375 mg ml⁻¹ black tea extract and two‐fold diluted tea bag infusion obtained from black tea when incubated at 25°C for 10 s. However, when concentrations of black and green tea extracts were equally adjusted to 344 µg ml⁻¹, green tea extracts showed more antiviral activity against SARS‐CoV‐2. This simple and highly respected beverage may be a cheap and widely acceptable means to reduce SARS‐CoV‐2 viral burden in the mouth and upper gastrointestinal and respiratory tracts in developed as well as developing countries.

Distinct association of VEGF-C and VEGF-D with prognosis in patients with chronic heart failure: the PREHOSP-CHF study

Background

The lymphatic system has been suggested to play an important role in cardiovascular (CV) diseases including heart failure (HF). Vascular endothelial growth factor C (VEGF-C) and VEGF-D are key regulators of lymphoangiogenesis.

Purpose

To investigate the association of VEGF-C and VEGF-D with prognosis in patients with chronic HF (CHF).

Methods

The PREHOSP-CHF study is a multicenter prospective cohort study to determine the predictive value of angiogenesis-related biomarkers in CHF. A total of 1,024 patients (mean age, 75.5±12.6 years; male, 58.7%) admitted to acute decompensated HF were included in the analyses. The primary outcome was MACE defined as a composite of CV death or HF hospitalization. The secondary outcomes were all-cause death, CV death, and HF hospitalizations. Serum levels of VEGF-C and VEGF-D, as well as N-terminal pro B-type natriuretic peptide (NT-proBNP), high sensitivity cardiac troponin-I (hs-cTnI), high sensitive C reactive protein (hs-CRP), VEGF, and soluble VEGF receptor-2 (sVEGFR-2) were measured at the time of discharge. Patients were followed-up over two years.

Results

Median [interquartile range] of VEGF-C and VEGF-D levels were 4821 [3633–6131] pg/ml and 404 [296–559] pg/ml, respectively. In multivariate stepwise regression analysis, independent determinants of VEGF-C levels were younger age, female gender, absence of prior HF hospitalization, chronic kidney disease, and anemia, lower ejection fraction, lower NT-proBNP levels, higher VEGF levels, and higher sVEGFR-2 levels, while those of VEGF-D levels were lower body mass index, presence of diabetes and atrial fibrillation, and higher NT-proBNP levels. During the follow-up, a total of 209 (20.4%) all-cause deaths, 112 (10.9%) CV deaths, and 309 (30.2%) HF hospitalizations occurred. After adjusting for established risk factors and CV biomarkers, VEGF-C levels were significantly and inversely associated with the incidence of MACE and non-CV death (Fig.1, model 4). On the other hand, VEGF-D levels were significantly and positively associated with the incidence of HF hospitalization (Fig. 1, model 4). When we divided the patients into 4 groups based on the median of VEGF-C and VEGF-D levels, patients with low VEGF-C and high VEGF-D showed significantly higher incidence of MACE, all-cause death, CV death, and HF hospitalization compared to those with high VEGF-C and low VEGF-D (Fig. 2).

Conclusions

Among patients with CHF, VEGF-C and VEGF-D had different characteristic and association with the incidence of adverse events. VEGF-C levels were inversely associated with the incidence of MACE and non-CV death, and VEGF-D levels were positively associated with the incidence of HF hospitalization. These results suggests different effects of VEGF-C and VEGF-D in CHF. Combination of VEGF-C and VEGF-D enables us to make good risk stratification in patients with CHF.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Grant-in-Aid for Clinical Research from the National Hospital Organization Figure 1Figure 2

Diagnostic performance of deep learning on 12-leads electrocardiography for recurrence after pulmonary vein isolation in patients with persistent atrial fibrillation

Background

Several patients with persistent atrial fibrillation (per-AF) suffer from recurrence after pulmonary vein isolation (PVI). Various methods to predict the recurrence were tried, but deep learning on 12-leads electrocardiography (ECG) after PVI was not studied.

Purpose

To elucidate diagnostic performance of deep learning on 12-leads ECG after PVI in patients with per-AF

Methods

We enrolled consecutive 109 patients with per-AF who underwent PVI (68.8±10.0 years, 83 males) excluding failure cases. We defined recurrence in 3–12 months after PVI. From the ECG just after PVI, five beats of each lead were sampled separately. Deep learning (convolutional neural network on bitmap ECG image) was performed by transfer learning of Inception-Resnet-V2 model. Gradient weighted class activation color mapping (GradCam) was performed to detect convolutional importance in the lead.

Results

Thirty-six patients showed recurrence in the period. Lead II (accuracy 0.701), aVR (0.690) were the top 2 leads of prediction, which showed larger accuracy than statistical accuracies of Non PV foci = SVC (accuracy = 0.541) and left atrial diameter &gt;50mm (0.596). In lead II, GradCam spotlighted strong convolution of latter half of P wave in recurrent case, and former half of P wave and T wave in no-recurrent case.

Conclusions

Deep learning on ECG was a powerful tool to predict recurrence of per-AF after PVI.

Funding Acknowledgement

Type of funding sources: None. Results of deep learningResults of GradCam

Exploration of electrocardiographic and echocardiographic findings to screen transthyretin amyloid cardiomyopathy in patients with mild left ventricular hypertrophy

Background

The transthyretin amyloid cardiomyopathy (ATTR-CM), a common condition in the elderly, is a life-threatening disease; however, it is treatable. The early accurate diagnosis is, therefore, an important key to improve the patient's outcomes. Electrocardiography and echocardiography are instant diagnostic tools with red flags for the screening of the ATTR-CM. In fact, ATTR-CM often mimics left ventricular hypertrophy (LVH), and the differential diagnosis is difficult to establish. Thus, the characteristics of cardiac amyloidosis may be obscured in ATTR-CM patients with mild LVH, possibly making the disease difficult to diagnose. Therefore, in this study, the effect of LVH on the occurrence of electrocardiographic and echocardiographic parameters for ATTR-CM was investigated, and their incremental value over the age for the screening of ATTR-CM in the patients with mild LVH was recorded.

Methods

This study retrospectively studied 319 consecutive nonischemic LVH patients with a sinus rhythm who underwent detailed diagnostic tests. The light chain-associated amyloidosis was an exclusion criterion. The mean left ventricular wall thickness (MWT) &lt;12 mm was defined as mild LVH, while MWT ≥12 mm was defined as moderate to severe LVH. The ATTR-CM was diagnosed with biopsy or 99 mTc-PYP scintigraphy. The elderly were defined as people aged ≥65 years in males and ≥70 years in females, according to the literature. Each electrocardiographic and echocardiographic parameter was binarized with an external cut-off point to increase the external validity, being the incremental benefit of each parameter over age for identifying ATTR-CM assessed using a receiver operating characteristic curve analysis and comparisons of the area under the curve (AUC).

Results

Fourteen patients (8%) among the 170 patients with mild LVH had ATTR-CM, while 27 patients (18%) among the 149 patients with moderate to severe LVH had ATTR-CM. The patients with mild LVH had fewer electrocardiographic and echocardiographic parameters, showing a significant difference between ATTR-CM and non-ATTR-CM patients than those with moderate to severe LVH (Table 1). Among several binarized parameters, the voltage-to-mass ratio, E/A ratio, the global longitudinal strain, and also the relative apical sparing pattern demonstrated additive value for identifying the ATTR-CM over aging (Table 2). In addition, the discriminative ability of the propensity score calculated from these four variables and age was considered excellent for the screening of ATTR-CM (AUC = 0.98).

Conclusion

The patients with mild LVH appear to have fewer electrocardiographic and echocardiographic specific findings of the ATTR-CM compared to patients with moderate to severe LVH. However, several red flags may be useful for screening ATTR-CM even in patients with a mild LVH.

Funding Acknowledgement

Type of funding sources: None. Table 1Table 2

Impact of atrial fibrillation on soluble fms-like tyrosine kinase-1 and cardiovascular events in patients with suspected or known coronary artery disease: the EXCEED-J study

Background

Soluble fms-like tyrosine kinase-1 (sFlt-1), a vascular endothelial growth factor (VEGF) antagonist, has been suggested as a marker of endothelial dysfunction. Circulating sFlt-1 levels are associated with adverse outcomes in patients with preeclampsia, chronic kidney disease, and heart failure. Atrial fibrillation (AF) and coronary artery disease (CAD) are both associated with endothelial dysfunction. However, whether sFlt-1 can predict cardiovascular (CV) events and whether AF modifies the relationship between sFlt-1 and CV events in patients with suspected or known CAD are unknown.

Methods

We performed a nationwide, multicenter, prospective cohort study to determine the prognostic value of sFlt-1 and other biomarkers in patients with suspected or known CAD undergoing elective angiography. Heparin-free fasting serum was collected from the peripheral vein to determine levels of sFlt-1, VEGF, placental growth factor, cystatin C, neutrophil gelatinase-associated lipocalin, N-terminal pro-brain natriuretic peptide (NT-proBNP), high-sensitivity cardiac troponin-I (hs-cTnI), and high-sensitivity C-reactive protein (hs-CRP). The primary outcome was 3-point major adverse CV events (3P-MACE) defined as a composite of CV death, nonfatal myocardial infarction, and nonfatal stroke. The secondary outcomes were all-cause death, CV death, and 5P-MACE defined as a composite of 3P-MACE, heart failure hospitalization, and coronary/peripheral artery revascularization.

Results

3311 patients were consecutively enrolled between Nov 2013 and May 2017. After excluding 56 ineligible patients, 3255 patients (324 AF and 2931 non-AF) were followed up over 3 years (follow-up rate, 99%). During the follow-up, 156 patients developed 3P-MACE, 215 died from any cause, 82 died from cardiovascular disease, and 1361 developed 5P-MACE. The sFlt-1 level was significantly higher in AF compared to non-AF patients (p&lt;0.001). Stepwise regression analysis revealed that the sFlt-1 level was independently associated with AF. After adjusting for potential clinical confounders, serum levels of sFlt-1, NT-proBNP, hs-cTnI and cystatin C, but not other biomarkers, were significantly associated with 3P-MACE in the entire cohort. These associations were still significant in non-AF patients, whereas only the sFlt-1 level was significantly associated with 3P-MACE in AF patients. Serum levels of sFlt-1, but not other biomarkers, were also significantly associated with CV death in AF patients. Among the biomarkers, only the hs-CRP level was significantly associated with all-cause death, and no biomarker was significantly associated with 5P-MACE in AF patients. Furthermore, sFlt-1 provided an incremental prognostic information for 3P-MACE to the model with potential clinical confounders in AF, but not in non-AF patients.

Conclusions

Serum levels of sFlt-1 were significantly associated with 3P-MACE in patients with suspected or known CAD. This association was pronounced in AF patients.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): The EXCEED-J study is supported by Health Labour Sciences Research Grant (2013-2014), AMED (2015-2017, Grant Number JP17ek0210008) and Grant-in-Aid for Clinical Research from the National Hospital Organization (2018-2020).

Flexural Properties and Polished Surface Characteristics of a Structural Colored Resin Composite

OBJECTIVE

The aim of this study was to determine the flexural properties and surface characteristics of a structural colored resin composite after different finishing and polishing methods, in comparison to those of conventional resin composites.

METHODS AND MATERIALS

A structural color resin composite, Omnichroma (OM, Tokuyama Corp, Chiyoda City, Tokyo, Japan), and two comparison resin composites, Filtek Supreme Ultra (FS, 3M, St Paul, MN, USA) and Tetric EvoCeram (TE, Ivoclar Vivadent, Schaan, Liechtenstein), were used. The flexural properties of the resin composites were determined in accordance with the ISO 4049 specifications. For surface properties, 70 polymerized specimens of each resin composite were prepared and divided into seven groups of 10. Surface roughness (Sa), gloss (GU), and surface free energy (SFE) were investigated after the following finishing and polishing methods. Three groups of specimens were finished with a superfine-grit diamond bur (SFD), and three with a tungsten carbide bur (TCB). After finishing, one of the two remaining groups was polished with a one-step silicone point (CMP), and the other with an aluminum oxide flexible disk (SSD). A group ground with SiC 320-grit was set as a baseline.

RESULTS

The average flexural strength ranged from 116.6 to 142.3 MPa in the following order with significant differences between each value: FS > TE > OM. The average E ranged from 6.8 to 13.2 GPa in the following order with significant differences between each value: FS > TE > OM. The average R ranged from 0.77 to 1.01 MJ/mm3 in the following order: OM > FS > TE. The Sa values of the OM groups polished with CMP and SSD were found to be significantly lower than those of the other resin composites, regardless of the finishing method. The GU values appeared to be dependent on the material and the finishing method used. The OM specimens polished with SSD showed significantly higher GU values than those polished with CMP. Most of the resin composites polished with SSD demonstrated significantly higher γS values compared to the other groups. Extremely strong negative correlations between Sa and GU in the combined data from the three resin composites and each resin composite and between Sa and γS in the OM specimens were observed; GU showed a strong positive correlation with γS in the same material.

CONCLUSION

These findings indicate that both flexural and surface properties are material dependent. Furthermore, the different finishing and polishing methods used in this study were observed to affect the Sa, GU, and SFE of the resin composites.

Diagnostic Accuracy of Screening Arterial Spin-Labeling MRI Using Hadamard Encoding for the Detection of Reduced CBF in Adult Patients with Ischemic Moyamoya Disease

BACKGROUND AND PURPOSE

Adult patients with ischemic Moyamoya disease are advised to undergo selective revascularization surgery based on cerebral hemodynamics. The purpose of this study was to determine the diagnostic accuracy of arterial spin-labeling MR imaging using Hadamard-encoded multiple postlabeling delays for the detection of reduced CBF in such patients.

MATERIALS AND METHODS

Thirty-seven patients underwent brain perfusion SPECT and pseudocontinuous arterial spin-labeling MR imaging using standard postlabeling delay (1525 ms) and Hadamard-encoded multiple postlabeling delays. For Hadamard-encoded multiple postlabeling delays, based on data obtained from the 7 sub-boluses with combinations of different labeling durations and postlabeling delays, CBF corrected by the arterial transit time was calculated on a voxel-by-voxel basis. Using a 3D stereotaxic template, we automatically placed ROIs in the ipsilateral cerebellar hemisphere and 5 MCA territories in the symptomatic cerebral hemisphere; then, the ratio of the MCA to cerebellar ROI was calculated.

RESULTS

The area under the receiver operating characteristic curve for detecting reduced SPECT-CBF ratios (<0.686) was significantly greater for the Hadamard-encoded multiple postlabeling delays-CBF ratios (0.885) than for the standard postlabeling delay-CBF ratios (0.786) (P = .001). The sensitivity and negative predictive value for the Hadamard-encoded multiple postlabeling delays-CBF ratios were 100% (95% confidence interval, 100%-100%) and significantly higher than the sensitivity (95% CI, 44%-80%) and negative predictive value (95% CI, 88%-97%) for the standard postlabeling delay-CBF ratio, respectively.

CONCLUSIONS

ASL MR imaging using Hadamard-encoded multiple postlabeling delays may be applicable as a screening tool because it can detect reduced CBF on brain perfusion SPECT with 100% sensitivity and a 100% negative predictive value in adult patients with ischemic Moyamoya disease.

Impaired preload reserve is an important haemodynamic characteristics that discriminates between physiological ageing and overt heart failure with preserved ejection fraction

Funding Acknowledgements

Type of funding sources: None.

Background

 Ageing process per se is a major risk factor for heart failure (HF). In fact, the incidence of HF with preserved ejection fraction (HFpEF) dramatically increases with age. Although ageing plays a central role in the development of HFpEF, not all the elderly patients develop clinical HFpEF. Multiple abnormalities in the cardiovascular system have been proposed to contribute to the development of HFpEF. However, the pathophysiology that discriminates between physiological ageing and overt HFpEF is incompletely understood.

Purpose

 The purpose of this study was to assess the effects of ageing on the cardiac structures and haemodynamics. Moreover, we evaluated the determinant factor that discriminates between physiological ageing and overt HFpEF by non-invasive preload increasing manoeuvre using leg-positive pressure (LPP) stress echocardiography.

Methods

 A total of 91 subjects were prospectively recruited in this study: 22 patients with HFpEF and 69 healthy controls. Normal controls were further stratified into 3 age groups: young (n = 19, 20-40 years of age), middle-aged (N = 25, 40-65 years) and elderly (n = 25, &gt;65 years). All subjects underwent LPP stress with a continuous external pressure of 90 mmHg around both lower limbs using dedicated airbags (Fig.). 

Results

 The left ventricular mass index (LVMI; young, 68 ± 19 g/m²; middle-age, 70 ± 18 g/m²; elderly, 84 ± 21 g/m²) and also the relative wall thickness (RWT; young, 0.34 ± 0.09; middle-age, 0.41 ± 0.06; elderly 0.55 ± 0.10) increased with ageing, which was accelerated in HFpEF (LVMI: 111 ± 32 g/m², RWT; 0.63 ± 0.19, ANOVA P &lt; 0.001, respectively). Although baseline LV ejection fraction and cardiac output were quite comparable between groups, E/e’ ratio significantly increased with with ageing (ANOVA P &lt; 0.001, Fig.). During LPP stress, E/e’ ratio significantly increased in the middle-aged and elderly groups (from 8.8 ± 2.7 to 9.7 ± 3.3, and from 11.4 ± 2.4 to 13.0 ± 2.2, P &lt; 0.05, respectively), which was further deteriorated in HFpEF (from 16.8 ± 5.8 to 18.0 ± 7.6, P &lt; 0.05). On the other hand, stroke volume index (SVi) significantly increased in each healthy group during LPP stress (young; from 45 ± 10 to 50 ± 11 mL/m², middle-age; from 39 ± 7 to 44 ± 6 mL/m² and elderly; from 37 ± 7 to 43 ± 8 mL/m², all P &lt; 0.001), while SVi failed to increase in the HFpEF group (from 45 ± 13 to 45 ± 14 mL/m², P = 0.60). In a multivariate logistic regression analysis, LVMI (hazard ratio; HR 1.055, P &lt; 0.05), baseline E/e’ (HR 1.444; P &lt; 0.05), and ΔSVi (HR 0.755; P &lt; 0.05) during LPP stress were the independent parameters that characterised overt HFpEF.

Conclusions

 Striking parallels between structure-function alterations were observed in the physiological cardiovascular ageing process, which was further accelerated in patients with HFpEF. Not only structural remodeling and impaired diastolic function, but also impaired systolic reserve during preload stress is important haemodynamic feature that characterise the pathophysiology of HFpEF.

Abstract Figure.

Association between clinical risk factors and left ventricular function in patients with breast cancer following chemotherapy

Funding Acknowledgements

Type of funding sources: None.

Background

The sequential or concurrent use of two different types of agents such as anthracyclines and trastuzumab may increase myocardial injury and cancer therapeutics-related cardiac dysfunction (CTRCD), which is often the result of the combined detrimental effect of the two therapies for breast cancer patients. For risk stratification to detect the development of CTRCD, the current position paper from the European Society of Cardiology (ESC) lists several factors associated with risk of cardiotoxicity.

Purpose

Our purpose was to investigate the impact of baseline risk factors on left ventricular (LV) function in patients with preserved LV ejection fraction (LVEF) who have undergone chemotherapy for breast cancer.

Methods

We studied 86 breast cancer patients treated with anthracyclines, trastuzumab, or both. Mean age was 59 ± 13 years and LVEF was 67 ± 5%. In accordance with the current definition, CTRCD was defined as a decline in LVEF of &gt;10% to an absolute value of &lt;53% after chemotherapy. Based on the 2016 ESC position paper, clinical risk factors for CTRCD were defined as: (1) a cumulative total doxorubicin dose of ≥ 240mg/m², (2) age ≥ 65-year-old, (3) body mass index ≥ 30kg/m², (4) a previous history of radiation therapy to chest or mediastinum, (5) B-type natriuretic peptide ≥ 100pg/mL, (6) a previous history of cardiovascular disease, (7) atrial fibrillation, (8) hypertension, (9) diabetes mellitus, (10) current or ex-smoker.

Results

The relative decrease in LVEF after chemotherapy for patients with more than four risk factors was significantly greater than that for patients without (-9.3 ± 10.8% vs. -2.2 ± 10.2%; p = 0.02). However, this finding did not apply to patients with more than one, two or three risk factors. Patients with more than four risk factors also tended to show a higher prevalence of CTRCD than those without (14.3% vs. 2.8%, p = 0.12). Moreover, patients with more than four risk factors were more likely to have higher LV mass index (109.3 ± 29.0g/m² vs. 83.2 ± 21.0g/m², p &lt; 0.001), lower global longitudinal strain (18.4 ± 2.8% vs. 20.0 ± 2.6%, p = 0.06) and higher E/e’ (10.4 (8.9-13.0) vs. 9.0 (7.4-10.9), p = 0.06) compared to those without. 

Furthermore, receiver-operator characteristics curve analysis showed that an optimal cut off value of a cumulative total doxorubicin dose for developing LV dysfunction in patients with more than any of four risk factors was lower than that in those without (180 mg/m² vs. 280 mg/m²).

Conclusions

Association between clinical risk factors and LV dysfunction following chemotherapy became stronger with an increase in the number of risk factors in breast cancer patients, and was especially strong for patients treated with chemotherapy who had more than four risk factors. Our findings can thus be expected to have clinical implications for better management of patients with breast cancer referred for chemotherapy.

Abstract Figure.

Preload stress echocardiography by using dynamic postural alteration can identify high risk patients with heart failure with reduced ejection fraction

Funding Acknowledgements

Type of funding sources: None.

Background

Haemodynamic assessment during stress testing is not commonly performed for patients with heart failure with reduced ejection fraction (HFrEF) due to its invasiveness, less feasibility, and safety concerns. Passive leg-lifting (PLL) manoeuvres have been introduced as a simple alternative for non-invasive preload stress testing; however, the haemodynamic load imposed on the cardiovascular system is unsatisfactory, which precludes the accurate assessment of the preload reserve for patients with HF.

Purpose

The purpose of this study was to assess the haemodynamic characteristics of patients with HFrEF in response to a preload stress during dynamic postural alterations by combining the semi-sitting position (SSP) and PLL. We also evaluated whether combined postural stress could be used for risk stratification for these patients.

Methods

For this study, 101 patients with HFrEF and 35 age- and sex-matched normal controls were prospectively recruited. At each postural position (i.e., baseline, SSP, and PLL), all standard echocardiographic and Doppler variables were obtained. Adverse cardiac events were prespecified as the combined endpoints of death from or hospitalisation for deteriorated HF, or sudden cardiac death. Clinical follow-up was conducted for a median of 7 months.

Results

During PLL stress, the stroke volume index (SVi) significantly increased in both controls (from 40 ± 6 to 43 ± 6 mL/m², P = 0.03) and HFrEF patients (from 31 ± 9 to 34 ± 10 mL/m², P = 0.03). Conversely, during SSP stress, the SVi significantly decreased for both controls (from 40 ± 6 to 37 ± 6 mL/m², P = 0.03) and HFrEF patients (31 ± 9 to 28 ± 8 mL/m², P = 0.03). During the follow-up period, 16 patients developed cardiac events. In patients without events, the Frank-Starling mechanism was well preserved (Fig. A). Namely, the SVi significantly increased from 31 ± 9 to 35 ± 10 mL/m² (P = 0.02) during PLL stress, while the SVi significantly decreased from 31 ± 8 to 28 ± 8 mL/m² (P = 0.02) during SSP stress. In contrast, for patients with cardiac events, the SVi did not change during postural alterations (n.s), which indicated that the failing heart operates on the flat portion of the Frank-Starling curve (Fig. A). When patients were divided into three equal sub-groups based on the total difference in the SVi during dynamic postural stress, patients with impaired preload reserve (third trimester, ΔSVi ≤ 3.0 mL/m²) showed significantly worse event-free survival than the other two sub-groups (Fig. B; P &lt; 0.001). In a Cox proportional-hazard analysis, baseline LVEF (hazard ratio 0.93; P = 0.04), and ΔSVi during postural stress (hazard ratio 0.76; P = 0.004) were predictors of future cardiac events.

Conclusions

The combined assessment of dynamic postural stress during PLL and SPP is a simple, time-saving, and easy-to-use clinical tool for the assessment of preload reserve for patients with HFrEF. Moreover, postural stress echocardiography proved to contribute to the risk stratification for these patients.

Abstract Figure.

Cardiac resynchronization therapy improves left atrial reservoir function through resynchronization of the left atrium in patients with heart failure

Funding Acknowledgements

Type of funding sources: None.

Background

The structural remodeling of the left atrium (LA) has been proposed as an important determinant of adverse outcomes in patients with heart failure (HF). However, little is known about the potential impact of LA mechanical dyssynchrony on its reservoir function and the prognosis of patients with HF. In addition, it has not been fully investigated whether cardiac resynchronization therapy (CRT) is also beneficial to LA function.

Purposes

The purposes of this study were to test whether left ventricular (LV) dyssynchrony may negatively affect LA synchronicity and reservoir function, and to assess whether residual LA dyssynchrony after CRT affects the prognosis in patients with HF with reduced ejection fraction (HFrEF).

Methods

This study included total of 90 subjects: 40 HFrEF with a wide-QRS complex (≧130 ms), 28 HFrEF with a narrow-QRS, and 22 age- and sex-matched normal controls. LA global longitudinal strain (LA-GLS) and LA dyssynchrony were quantified using speckle-tracking strain analysis. LA dyssynchrony was defined as the maximal difference of time-to-peak strain (LA time-diff). All wide-QRS HFrEF received CRT, and event-free survival was tracked for 24 months.

Results

At baseline, HFrEF patients showed significant LA remodeling coupled with the reduced LA reservoir function, as evidenced by larger LA volume index (LAVi: 46 ± 16 vs. 30 ± 14 mL/m², P &lt; 0.01) and smaller LA-GLS (13.0 ± 4.8 vs. 30.6 ± 10.7%, P &lt; 0.01). Of note was that, not only LV dyssynchrony (381 ± 178 vs. 177 ± 62 ms, P &lt; 0.01) but also LA dyssynchrony (298 ± 136 vs. 186 ± 78 ms, P &lt; 0.01) were significantly larger in patients with HFrEF compared to normal subjects and this applied even more to patients with a wide-QRS complex. All patients with a wide-QRS complex underwent CRT, and only responders exhibited the significant decrease in LA time-diff (from 338 ± 123 to 245 ± 141 ms, P &lt; 0.05) and increase in LA-GLS (from 11.9 ± 4.7 to 19.6 ± 10.1%, P &lt; 0.05) in parallel with the reduction in LAVi (from 48 ± 17 to 37 ± 18 mL/m², P &lt; 0.05) at 6 months after CRT. Receiver operating characteristic curve analysis identified the optimal cut-off value of LA time-diff at 6 months after CRT as 202 ms (P &lt; 0.05) and that of LA-GLS as 14.6% (P &lt; 0.05) for predicting adverse cardiac events. The patients whose LA time-diff reduced &lt;202 ms after CRT showed significantly favorable event-free survival than the others. Similarly, the patients whose LA-GLS improved &gt;14.6% after CRT exhibited significantly favorable event-free survival than the others (P &lt; 0.05, respectively). Of note was that, when the patients were restricted to CRT responders only, those who showed LA time-diff less than 202 ms at 6 months after CRT almost never experienced cardiac events (P &lt; 0.05).

Conclusions

The improved LV coordination by CRT also resulted in resynchronization of discoordinated LA wall motion and a consecutive improvement of LA reservoir function, which ultimately lead to the favorable outcome for HFrEF patients with wide-QRS complex.

Abstract Figure.

preoperative right ventricular overwork is a major determinant of residual pulmonary arterial hypertension in patients with repaired arterial septal defect

Funding Acknowledgements

Type of funding sources: None.

Background

The haemodynamic effect of atrial septal defect (ASD) is a chronic volume overload of the right heart and pulmonary vasculature. Pulmonary overcirculation is generally compensated for by the right ventricular (RV) and pulmonary arterial (PA) reserve. However, in a subset of patients, prolonged pulmonary overcirculation insidiously induces obstructive pulmonary vasculopathy, which results in postoperative residual pulmonary arterial hypertension (PAH) after ASD closure. Postoperative PAH is a major concern because it is closely associated with poor outcomes and impaired quality of life. However, to date, no clinically robust predictors of postoperative residual PAH have been clearly identified.

Purpose

This study sought to assess the haemodynamic characteristics of ASD patients in terms of mechano-energetic parameters and to identify the predictors of postoperative residual PAH in these patients.

Methods

A total of 120 ASD patients (age: 58 ± 17 years) and 46 normal controls were recruited. As previously reported, the simplified RV contraction pressure index (sRVCPI) was calculated as an index of RV external work by multiplying the tricuspid annular plane systolic excursion (TAPSE) by the pressure gradient between the RV and right atrium. RV- PA coupling was evaluated using TAPSE divided by PA systolic pressure as an index of the RV length-force relationship. These parameters were measured both at baseline and 6 months after ASD closure.

Results

As expected, baseline sRVCPI was significantly greater in patients with ASD than in controls (775 ± 298 vs. 335 ± 180 mm Hg • mm, P &lt; 0.01), which indicated significant "RV overwork". As a result, RV-PA coupling in ASD patients was significantly impaired compared to that in controls (0.9 ± 0.8 vs. 3.5 ± 1.7 mm/mm Hg, P &lt; 0.01). All 120 ASD patients underwent transcatheter or surgical shunt closure; 15 of them had residual PAH after closure. After 6 months, RV-PA coupling index significantly improved in patients without residual PAH, from 0.96 ± 0.81 to 1.27 ± 1.24 mm/mm Hg (P = 0.02). Furthermore, RV load was markedly reduced, with sRVCPI falling from 691 ± 258 to 434 ± 217 mm Hg • mm, P &lt; 0.01). However, in patients with residual PAH, RV-PA coupling index deteriorated from 0.64 ± 0.23 to 0.53 ± 0.12 mm/mm Hg (P &lt; 0.01). As a result, RV overload was not significantly relieved (sRVCPI; from 971 ± 382 to 783 ± 166 mm Hg • mm, P = 0.22). In a multivariate analysis, baseline pulmonary vascular resistance (hazard ratio 1.009; P &lt; 0.01) and preoperative sRVPCI (hazard ratio 1.003; P &lt; 0.01) revealed to be independent predictors of residual PAH.

Conclusion

In terms of mechano-energetic function, preoperative "RV overwork" can be used as a robust predictor of an impaired RV-PA relationship in ASD patients. Moreover, periodic assessment of sRVPCI may contribute to the better management for patients with unrepaired ASD.

Abstract Figure.

siRNA potency enhancement via chemical modifications of nucleotide bases at the 5'-end of the siRNA guide strand

Small interfering RNAs (siRNAs) can be utilized not only as functional biological research tools but also as therapeutic agents. For the clinical use of siRNA as drugs, various chemical modifications have been used to improve the activity of siRNA drugs, and further chemical modifications are expected to improve the utility of siRNA therapeutics. As the 5' nucleobase of the guide strand affects the interaction between an siRNA and AGO2 and target cleavage activity, structural optimization of this specific position may be a useful strategy for improving siRNA activity. Here, using the in silico model of the complex between human AGO2 MID domain and nucleoside monophosphates, we screened and synthesized an original adenine-derived analog, 6-(3-(2-carboxyethyl)phenyl)purine (6-mCEPh-purine), that fits better than the natural nucleotide bases into the MID domain of AGO2. Introduction of the 6-mCEPh-purine analog at the 5'-end of the siRNA guide strand significantly enhanced target knockdown activity in both cultured cell lines and in vivo animal models. Our findings can help expand strategies for rationally optimizing siRNA activity via chemical modifications of nucleotide bases.

The Influence of the COVID-19 Pandemic on Physical Activity and New Incidence of Frailty among Initially Non-Frail Older Adults in Japan: A Follow-Up Online Survey

OBJECTIVES

The objective of this study was to investigate the influence of the COVID-19 pandemic on physical activity (PA) and the incidence of frailty among initially non-frail older adults in Japan.

DESIGN

A follow-up online survey.

SETTING AND SUBJECTS

Among the 1,600 baseline online survey participants, 388 adults were already frail, and 275 older adults did not respond to the follow-up survey. Thus, the final number of participants in this study was 937 (follow-up rate: 77.3%).

METHODS

We assessed the total PA time at four time points according to the COVID-19 waves in Japan: January 2020 (before the pandemic), April 2020 (during the first wave), August 2020 (during the second wave), and January 2021 (during the third wave). We then investigated the incidence of frailty during a one-year follow-up period (during the pandemic).

RESULTS

The total PA time during the first, second, and third waves of the pandemic decreased from the pre-pandemic PA time by 33.3%, 28.3%, and 40.0%, respectively. In particular, the total PA time of older adults who were living alone and socially inactive decreased significantly: 42.9% (first wave), 50.0% (second wave), and 61.9% (third wave) less than before the pandemic, respectively. Additionally, they were at a significantly higher risk of incident frailty than those who were not living alone and were socially active (adjusted odds ratio: 2.04 [95% confidence interval: 1.01-4.10]).

CONCLUSION

Our findings suggest that older adults who live alone and are socially inactive are more likely to experience incident frailty/disability due to decreased PA during the pandemic. Understanding this mechanism may be crucial for maintaining the health status of older adults.

The dual pocket binding novel tankyrase inhibitor K-476 enhances the efficacy of immune checkpoint inhibitor by attracting CD8+ T cells to tumors

The Wnt/β-catenin pathway, which is associated with disease progression, is activated in many cancers. Tankyrase (TNKS) has received attention as a target molecule for Wnt/β-catenin pathway inhibition. We identified K-476, a novel TNKS inhibitor, a dual pocket binder that binds to both the nicotinamide and ADP-ribose pockets. In a human colon cancer cell line, K-476 specifically and potently inhibited TNKS and led to stabilization of the Axin protein, resulting in Wnt/β-catenin pathway suppression. Aberrant Wnt/β-catenin pathway activation was recently reported as a possible mechanism of ineffectiveness in immune checkpoint inhibitor (ICI) treatment. Because the Wnt/β-catenin pathway activation causes dendritic cell inactivation and suppresses chemokine production, resulting in a paucity of CD8⁺ T cells in tumor tissue, which is an important effector of ICIs. Thus, TNKS inhibitors may enhance the efficacy of ICIs. To examine whether K-476 enhances the antitumor effect of anti-PD-L1 antibodies, K-476 was administered orally with an anti-PD-L1 antibody to melanoma-bearing C57BL/6J mice. Although K-476 was ineffective as a monotherapy, it significantly enhanced the antitumor effect in combination with anti-PD-L1 antibody. In mice, intra-tumor infiltration of CD8⁺ T cells was increased by combination treatment. K-476 upregulated the chemokine expression (e.g., Ccl3 and Ccl4), which attracted CD8⁺ T cells. This was considered to contribute to the increased CD8⁺ T cells in the tumor microenvironment. Furthermore, while the potential gastrointestinal toxicity of TNKS inhibitors has been reported, it was not observed at effective doses. Thus, K-476 could be an attractive therapeutic option to enhance the efficacy of ICIs.