Impact of intratumoral microbiome on tumor immunity and prognosis in human pancreatic ductal adenocarcinoma

BACKGROUND

Recent evidence suggests that the presence of microbiome within human pancreatic ductal adenocarcinoma (PDAC) tissue potentially influences cancer progression and prognosis. However, the significance of tumor-resident microbiome remains unclear. We aimed to elucidate the impact of intratumoral bacteria on the pathophysiology and prognosis of human PDAC.

METHODS

The presence of intratumoral bacteria was assessed in 162 surgically resected PDACs using quantitative polymerase chain reaction (qPCR) and in situ hybridization (ISH) targeting 16S rRNA. The intratumoral microbiome was explored by 16S metagenome sequencing using DNA extracted from formalin-fixed paraffin-embedded tissues. The profile of intratumoral bacteria was compared with clinical information, pathological findings including tumor-infiltrating T cells, tumor-associated macrophage, fibrosis, and alterations in four main driver genes (KRAS, TP53, CDKN2A/p16, SMAD4) in tumor genomes.

RESULTS

The presence of intratumoral bacteria was confirmed in 52 tumors (32%) using both qPCR and ISH. The 16S metagenome sequencing revealed characteristic bacterial profiles within these tumors, including phyla such as Proteobacteria and Firmicutes. Comparison of bacterial profiles between cases with good and poor prognosis revealed a significant positive correlation between a shorter survival time and the presence of anaerobic bacteria such as Bacteroides, Lactobacillus, and Peptoniphilus. The abundance of these bacteria was correlated with a decrease in the number of tumor-infiltrating T cells positive for CD4, CD8, and CD45RO.

CONCLUSIONS

Intratumoral infection of anaerobic bacteria such as Bacteroides, Lactobacillus, and Peptoniphilus is correlated with the suppressed anti-PDAC immunity and poor prognosis.

Metabolic Syndrome Accelerates the Age-Related Increase of Intraductal Papillary Mucinous Neoplasm of the Pancreas

OBJECTIVES

Aging is associated with a high prevalence of pancreatic cysts and intraductal papillary mucinous neoplasms (IPMNs). Metabolic syndrome (MS) may increase the risk of neoplasms, including those that develop in the pancreas. However, the influence of factors associated with MS on the development of IPMN remains unclear.

METHODS

A total of 9363 patients who underwent abdominal ultrasound examinations between April 2012 and May 2013 were included in this study. Multivariate logistic regression analysis was performed to identify factors associated with the presence of IPMN by age.

RESULTS

Pancreatic cysts were detected in 198 of 9363 patients, of whom 129 were found to have IPMNs. The presence of IPMN significantly correlated with age (10-year increments; odds ratio, 2.73; 95% CI, 2.28-3.29; P < 0.001). High body mass index, history of smoking, hyperlipidemia, hypertension, and MS were associated with a higher prevalence of IPMN with advancing age. In multivariate analysis, the presence of IPMN was more frequent in elderly patients with MS (odds ratio, 3.14; 95% CI, 3.14-6.72; P = 0.003).

CONCLUSIONS

The present study suggests that the incidence of IPMN increases with age and is accelerated in the presence of MS.

A comprehensive analysis of tumor-stromal collagen in relation to pathological, molecular, and immune characteristics and patient survival in pancreatic ductal adenocarcinoma

BACKGROUND

Abundant collagen deposition is a hallmark of pancreatic ductal adenocarcinomas (PDACs). This study clarified the interactive relationship between tumor-stromal collagen, molecular and immune characteristics, and tumor pr ogression in human PDAC.

METHODS

We performed a comprehensive examination using an integrative molecular pathological epidemiology database on 169 cases with resected PDAC . The amount of tumor-stromal collagen was quantified through digital imaging analysis for Elastica van Gieson-stained whole-section tumor slides. We analyzed the association of tumor-stromal collagen with gene alterations (KRAS, TP53, CDKN2A/p16, and SMAD4), immune parameters (CD4+ tumor-infiltrating lymphocytes [TILs], CD8+ TILs, FOXP3+ TILs, and tertiary lymphoid structures), and patient prognosis.

RESULTS

Low amounts of tumor-stromal collagen were associated with poor differentiation (multivariable OR = 3.82, 95%CI = 1.41-12.2, P = 0.008) and CDKN2A/p16 alteration (OR [95%CI] = 2.06 [1.08-4.02], P = 0.03). Tumors with low collagen levels had shorter overall survival (HR [95%CI] = 2.38 [1.59-3.56], P < 0.0001). In the S-1 and gemcitabine (GEM) treatment groups, low tumor-stromal collagen was linked to poor prognosis of patients with PDAC (S-1 group: multivariable HR [95%CI] = 2.76 [1.36-5.79], P = 0.005; GEM group: multivariate HR [95%CI] = 2.91 [1.34-6.71], P = 0.007). Additionally, low amounts of tumor-stromal collagen were also linked to low levels of CD4+ TILs (P = 0.046), CD8+ TILs (P = 0.09), and tertiary lymphoid structures (P = 0.001).

CONCLUSIONS

Tumor-stromal collagen deposition may play a crucial role in modulating tumor-immune microenvironment and determining response to adjuvant chemotherapy and patient survival outcomes.

Association of Sarcopenia with a Poor Prognosis and Decreased Tumor-Infiltrating CD8-Positive T Cells in Pancreatic Ductal Adenocarcinoma: A Retrospective Analysis

BACKGROUND

Sarcopenia, defined as a loss of skeletal muscle mass and quality, is found in 30-65% of patients with pancreatic ductal adenocarcinoma (PDAC) at diagnosis, and is a poor prognostic factor. However, it is yet to be evaluated why sarcopenia is associated with poor prognosis. Therefore, this study elucidated the tumor characteristics of PDAC with sarcopenia, including driver gene alterations and tumor microenvironment.

PATIENTS AND METHODS

We retrospectively analyzed 162 patients with PDAC who underwent pancreatic surgery between 2008 and 2017. We defined sarcopenia by measuring the skeletal muscle mass at the L3 level using preoperative computed tomography images and evaluated driver gene alteration (KRAS, TP53, CDKN2A/p16, and SMAD4) and tumor immune (CD4+, CD8+, and FOXP3+) and fibrosis status (stromal collagen).

RESULTS

In localized-stage PDAC (stage ≤ IIa), overall survival (OS) and recurrence-free survival were significantly shorter in the sarcopenia group than in the non-sarcopenia group (2-year OS 89.7% versus 59.1%, P = 0.03; 2-year RFS 74.9% versus 50.0%, P = 0.02). Multivariate analysis revealed that sarcopenia was an independent poor prognostic factor in localized-stage PDAC. Additionally, tumor-infiltrating CD8+ T cells in the sarcopenia group were significantly less than in the non-sarcopenia group (P = 0.02). However, no difference was observed in driver gene alteration and fib.rotic status. These findings were not observed in advanced-stage PDAC (stage ≥ IIb).

CONCLUSIONS

Sarcopenia was associated with a worse prognosis and decreased tumor-infiltrating CD8+ T cells in localized-stage PDAC. Sarcopenia may worsen a patient's prognosis by suppressing local tumor immunity.

Benefits of pancreatic parenchymal endoscopic ultrasonography in predicting microscopic precancerous lesions of pancreatic cancer

Pancreatic cancer primarily arises from microscopic precancerous lesions, such as pancreatic intraepithelial neoplasia (PanIN) and acinar-to-ductal metaplasia (ADM). However, no established method exists for predicting pancreatic precancerous conditions. Endoscopic ultrasonography (EUS) can detect changes in pancreatic parenchymal histology, including fibrosis. This study aimed to elucidate the relationship between pancreatic parenchymal EUS findings and microscopic precancerous lesions. We retrospectively analyzed 114 patients with pancreatobiliary tumors resected between 2010 and 2020 and evaluated the association between pancreatic parenchymal EUS findings and the number of PanIN, ADM, and pancreatic duct gland (PDG). Of the 114 patients, 33 (29.0%), 55 (48.2%), and 26 (22.8%) had normal EUS findings, hyperechoic foci/stranding without lobularity, and hyperechoic foci/stranding with lobularity, respectively. Multivariate analyses revealed that abnormal EUS findings were significantly associated with the frequency of PanIN (hyperechoic foci/stranding without lobularity: OR [95% CI] = 2.7 [1.0-7.3], with lobularity: 6.5 [1.9-22.5], P_trend = 0.01) and ADM (hyperechoic foci/stranding without lobularity: 3.1 [1.1-8.2], with lobularity: 9.7 [2.6-36.3], P_trend = 0.003) but not with PDG (hyperechoic foci/stranding without lobularity: 2.2 [0.8-5.8], with lobularity: 3.2 [1.0-10.2], P_trend = 0.12). We observed a trend toward a significantly higher number of precancerous lesions in the following order: normal findings, hyperechoic foci/stranding without lobularity, and hyperechoic foci/stranding with lobularity. Pancreatic parenchymal EUS findings were associated with the increased frequency of PanIN and ADM. Lobularity may help predict the increased number of precancerous lesions.

Integrated analysis of tertiary lymphoid structures in relation to tumor-infiltrating lymphocytes and patient survival in pancreatic ductal adenocarcinoma

BACKGROUND

Tertiary lymphoid structure (TLS) reflects an intense immune response against cancer, which correlates with favorable patient survival. However, the association of TLS with tumor-infiltrating lymphocytes (TILs) and clinical outcomes has not been investigated comprehensively in pancreatic ductal adenocarcinoma (PDAC).

METHODS

We utilized an integrative molecular pathological epidemiology database on 162 cases with resected PDAC, and examined TLS in relation to levels of TILs, patient survival, and treatment response. In whole-section slides, we assessed the formation of TLS and conducted immunohistochemistry for tumor-infiltrating T cells (CD4, CD8, CD45RO, and FOXP3). As confounding factors, we assessed alterations of four main driver genes (KRAS, TP53, CDKN2A [p16], and SMAD4) using next-generation sequencing and immunohistochemistry, and tumor CD274 (PD-L1) expression assessed by immunohistochemistry.

RESULTS

TLSs were found in 112 patients with PDAC (69.1%). TLS was associated with high levels of CD4⁺ TILs (multivariable odds ratio [OR], 3.50; 95% confidence interval [CI] 1.65-7.80; P = 0.0002), CD8⁺ TILs (multivariable OR, 11.0; 95% CI 4.57-29.7, P < 0.0001) and CD45RO⁺ TILs (multivariable OR, 2.65; 95% CI 1.25-5.80, P = 0.01), but not with levels of FOXP3⁺ TILs. TLS was associated with longer pancreatic cancer-specific survival (multivariable hazard ratio, 0.37; 95% CI 0.25-0.56, P < 0.0001) and favorable outcomes of adjuvant S-1-treatment. TLS was not associated with driver gene alterations but tumor CD274 negative expression.

CONCLUSIONS

Our comprehensive data supports the surrogacy of TLS for vigorous anti-tumor immune response characterized by high levels of helper and cytotoxic T cells and their prognostic role.

Progression of Recurrent Pancreatitis to Chronic Pancreatitis within 3 Years due to SPINK1 Mutation IVS3+2T>C

When the etiology of pancreatitis cannot be determined despite sufficient investigation, recurrence and progression to chronic pancreatitis often involve genetic mutations. Herein, we describe a case of recurrent pancreatitis with the IVS3+2T>C mutation in the serine protease inhibitor Kazal type 1 (SPINK1) gene that progressed to chronic pancreatitis in only 3 years. A 35-year-old man was referred to our hospital, where he was diagnosed with mild pancreatitis and was treated conservatively. However, the patient experienced recurrent episodes of pancreatitis, which progressed to become chronic pancreatitis with a pancreatic calcification 1 year later. After 3 years, the patient developed pancreatic duct stenosis and required a pancreatic duct stent placement. Regarding the cause of chronic pancreatitis, alcohol abuse was ruled out based on history taking. Considering the course of treatment, autoimmune pancreatitis and obstructive pancreatitis, such as pancreatic divisum, were also ruled out. Finally, a germline genetic test was performed to determine the etiology of pancreatitis, which revealed the IVS3+2T>C mutation in SPINK1. This case shows the importance of genetic testing in patients with idiopathic pancreatitis to determine their etiology and is a rare incident that can report the progression of the disease from acute to chronic pancreatitis.

Lobularity rather than hyperechoic foci/stranding on endoscopic ultrasonography is associated with more severe histological features in chronic pancreatitis

BACKGROUND AND AIM

Endoscopic ultrasonography (EUS) findings of the pancreatic parenchyma, such as hyperechoic foci/stranding and lobularity, may be associated with the severity of chronic pancreatitis (CP). However, the correlation between parenchymal EUS findings and histology remains unclear. We designed a large-scale retrospective study analyzing over 200 surgical specimens to elucidate the association between parenchymal EUS findings and histological features.

METHODS

Clinical data of 221 patients with pancreatobiliary tumors who underwent preoperative EUS and pancreatic surgery between January 2010 and November 2020 were reviewed to investigate the association between parenchymal EUS findings and histological features at the pancreatic body. None of these patients met the definition of CP.

RESULTS

Of the 221 patients, 87 (39.4%), 89 (40.2%), and 45 (20.4%) had normal EUS findings, hyperechoic foci/stranding without lobularity, and hyperechoic foci/stranding with lobularity, respectively. In the multivariate analyses, parenchymal EUS findings significantly correlated with histological CP findings of fibrosis, inflammation, and atrophy (hyperechoic foci/stranding without lobularity vs hyperechoic foci/stranding with lobularity, odds ratio [95% confidence interval]: 4.1 [2.2-7.9] vs 31.3 [9.3-105.6], P_trend  < 0.001; 3.9 [1.9-8.2] vs 21.8 [8.0-59.4], P_trend  < 0.001; and 4.0 [2.0-7.8] vs 22.9 [7.0-74.5], P_trend  < 0.001, respectively). Further, a trend toward higher histological grade was observed in the following order: normal findings, hyperechoic foci/stranding without lobularity, and hyperechoic foci/stranding with lobularity.

CONCLUSIONS

Endoscopic ultrasonography findings of the pancreatic parenchyma may be associated with the histological conditions in CP, such as pancreatic fibrosis, inflammation, and atrophy. Lobularity reflects more severe histological conditions than does hyperechoic foci/stranding.

Fast-forward scaling theory

Speed is the key to further advances in technology. For example, quantum technologies, such as quantum computing, require fast manipulations of quantum systems in order to overcome the effect of decoherence. However, controlling the speed of quantum dynamics is often very difficult due to both the lack of a simple scaling property in the dynamics and the infinitely large parameter space to be explored. Therefore, protocols for speed control based on understanding of the dynamical properties of the system, such as non-trivial scaling property, are highly desirable. Fast-forward scaling theory (FFST) was originally developed to provide a way to accelerate, decelerate, stop and reverse the dynamics of quantum systems. FFST has been extended in order to accelerate quantum and classical adiabatic dynamics of various systems including cold atoms, internal state of molecules, spins and solid-state artificial atoms. This paper describes the basic concept of FFST and reviews the recent developments and its applications such as fast state-preparations, state protection and ion sorting. We introduce a method, called inter-trajectory travel, recently derived from FFST. We also point out the significance of deceleration in quantum technology. This article is part of the theme issue 'Shortcuts to adiabaticity: theoretical, experimental and interdisciplinary perspectives'.

Diagnostic performance of angiography-derived index of microvascular resistance: a systematic review and pooled meta-analysis

Background

The index of microvascular resistance (IMR) is an established measurement of coronary microcirculation status. However, it has not been widely incorporated into routine practice due to need for intracoronary instrumentation (pressure wire) and hyperaemic agents. Several angiography-derived quantitative flow ratio-based indexes of microvascular resistance (angio-IMR) have been proposed rekindling the interest for the assessment and management of microvascular disease.

Purpose

To review the overall diagnostic accuracy of angio-IMR against wire based IMR.

Methods

A systematic review of the literature was performed and studies comparing angio-IMR with wire based IMR were included. Individual data was extracted using semi-automatic digitalization. Correlation of angio-IMR with IMR and its diagnostic performance against IMR were analysed.

Results

Six studies directly comparing angio-IMR with IMR were included. Data extraction rate was 85.1% (582/684 vessels). There was a linear correlation between angio-IMR and IMR (β=0.483, R square=0.298) (Figure 1A). Pooled sensitivity was 77%, specificity was 66%, positive predictive value was 65%, negative predictive value was 78%, and accuracy was 71.0%. Pooled area under receiver operator curve of angio-IMR for predicting IMR diagnosed coronary microvascular disease was 0.754 (95% confidential interval 0.715 to 0.793) (Figure 1B). Similar diagnostic performance was observed in subgroups of patients with or without ST-segment elevation myocardial infarction.

Conclusions

Currently available angio-IMR showed a clearly useful discrimination and diagnostic performance against the standard of wire based IMR.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): China Scholarship Council

Prevalence and distribution of non-pulmonary vein atrial fibrillation triggers in real-world clinical settings

Background

Epidemiology of non-pulmonary vein (PV) triggers of atrial fibrillation (AF) is not fully known.

Purpose

This study aimed to clarify the prevalence and distribution of non-PV triggers in real-world clinical settings of AF catheter ablation.

Methods

One-thousand and twenty patients undergoing AF ablations were retrospectively analyzed (mean age 65 years old, 702 males (69%), 506 paroxysmal and 514 non-paroxysmal). Induction and observation of AF triggers were attempted using intravenous isoproterenol/adenosine triphosphate and repeated direct current cardioversion during AF in each session. Documentable non-PV AF triggers were characterized in the studied population. Premature atrial contractions that did not initiate AF were excluded.

Results

A hundred and twenty-six non-PV triggers were documented in 108 patients (10.6%). Non-PV trigger was documented in 6.3% of 1st session cases, whereas 30.9% of recurrent cases undergoing multiple sessions (p&lt;0.0001). Left atrial (LA) posterior wall was the most prevalent site (N=34), followed by 30 intra-atrial septum (IAS), 29 superior vena cava (SVC), 13 crista terminalis, 7 right atrial (RA) free wall, 6 LA anterior wall, 3 coronary sinus (CS), 3 left atrial appendage, and 1 persistent left superior vena cava (LSVC). We classified those non-PV triggers into 4 groups; 43 LA, 33 thoracic veins (SVC, CS and LSVC), 30 IAS and 20 RA. Thoracic vein/RA origins were more prevalently detected in paroxysmal AF cases (57%) compared to non-paroxysmal AF (28%) (p&lt;0.01). Conversely, LA origin was more prevalently detected in non-paroxysmal AF cases (48%) compared to paroxysmal AF (20%) (p&lt;0.01).

Conclusions

Prevalence of non-PV trigger in cases undergoing multiple sessions is extremely high, suggesting a particular importance of non-PV trigger targeting in patients with recurrent AF undergoing 2nd or 3rd ablation sessions. Progressive nature of AF with newly generated AF triggers should be under consideration. Distributions of non-PV triggers are largely different between paroxysmal and non-paroxysmal AF. These findings may help ablation strategy regarding non-PV trigger targeting in practice.

Funding Acknowledgement

Type of funding sources: None.

Impact of bifurcation lesion on 10-year mortality in the SYNTAX trial

Background

Percutaneous coronary intervention (PCI) of bifurcation lesions is associated with higher rates of adverse events, and currently it is unclear whether PCI or coronary artery bypass grafting (CABG) is the safer treatment for these patients at very long-term follow up.

Objectives

To investigate the impact of bifurcation lesions on observed all-cause 10-year mortality in the SYNTAX trial.

Methods

In the SYNTAX Extended Survival study, 10-year observed mortality was compared among four groups: (a) presence of ≥1 bifurcation lesion and treatment with PCI (n=649), (b) no bifurcation lesion and treatment with PCI (n=248), (c) presence of ≥1 bifurcation lesion and treatment with CABG (n=651), and (d) no bifurcation lesion and treatment with CABG (n=239).

Results

Compared to patients without bifurcations, those with bifurcation lesion(s) treated with PCI had a significantly higher risk of all-cause death (19.8% vs 30.1%; HR: 1.55, 95% CI: 1.12 to 2.14; p=0.007), whereas following CABG, mortality was similar in patients with or without bifurcation lesion(s) (23.3% vs 23.0%; HR: 0.81, 95% CI: 0.59 to 1.12; p=0.207). (Figure1) There was a significant interaction between bifurcation lesion(s) and treatment arm (p for interaction=0.006).

In PCI patients, at 5-years there was no significant difference in mortality between 1- vs 2-stent techniques, whereas at 10-years, a 2-stent technique was associated with higher mortality (33.3% vs 25.9%; HR: 1.51, 95% CI: 1.06 to 2.14; p=0.021, Figure2).

Conclusions

Bifurcation lesion(s) require special attention from the heart team discussion, considering the higher 10-year all-cause mortality associated with PCI. Careful evaluation of bifurcation lesion complexity may be helpful in decision-making.

Funding Acknowledgement

Type of funding sources: Private grant(s) and/or Sponsorship. Main funding source(s): The SYNTAX Extended Survival study was supported by the German Foundation of Heart Research (Frankfurt am Main, Germany). The SYNTAX trial, during 0-5 years follow-up, was funded by Boston Scientific Corporation (Marlborough, MA, USA). Both sponsors had no role in the study design, data collection, data analyses, and interpretation of the study data, nor were involved in the decision to publish the final manuscript. The principal investigators and authors had complete scientific freedom.

Geographic disparity in 10-year mortality after coronary artery revascularization in the SYNTAXES trial

Aims

To investigate geographic disparity in long-term mortality following revascularization in patients with complex coronary artery disease (CAD).

Methods and results

The SYNTAXES trial randomized 1800 patients with three-vessel and/or left main CAD to percutaneous coronary intervention (PCI) or coronary artery bypass grafting (CABG) and assessed their survival at 10-years. Patients were stratified according to the region of recruitment: North America (N-A, n=245), Eastern Europe (E-E: Poland, Hungary, Czech, n=189), Northern Europe (N-E: United Kingdom, Sweden, Norway, Latvia, Finland, and Denmark, n=425), Southern Europe (S-E: Spain, Portugal, and Italy, n=263), and Western Europe (W-E: Netherlands, Germany, France, Belgium, and Austria, n=678), which also served as the reference group. Compared to W-E, patients were younger in E-E (62 vs 65 years, p&lt;0.001), and less frequently male in N-A (65.3% vs 79.6%, p&lt;0.001). Diabetes (16.0% vs 25.4%, p&lt;0.001) and peripheral vascular disease (6.8% vs 10.9%, p=0.025) were less frequent in N-E than W-E. Ejection fraction was highest in W-E (62% vs 56%, p&lt;0.001). Compared to W-E, the mean anatomic SYNTAX score was higher in S-E (29 vs 31, p=0.008) and lower in N-A (26, p&lt;0.001). Crude ten-year mortality was similar in N-A (31.6%), and W-E (30.7%), and significantly lower in E-E (22.5%, p=0.041), N-E (21.9%, p=0.003) and S-E (22.0%, p=0.014) as presented in left-middle lower of the graphical abstract. We adjusted the survival curves by following factors based on previous report; age, sex, medically treated diabetes, current smokers, peripheral vascular disease, chronic obstructive pulmonary disease, chronic kidney disease, left ventricular ejection fraction, disease type, and anatomical SYNTAX score [1]. When the differences in baseline characteristics were adjusted, mortality was still significantly lower in N-E (HR 0.85, 95% CI [0.74–0.97], p=0.019) and trended lower in S-E (HR 0.72 95% CI [0.52–0.99] p=0.043) compared to W-E (right middle-lower of the graphical abstract). However, no significant interaction (P interaction = 0.728) between region and modality of revascularization was seen.

Discussion and conclusions

The main findings of this study are:

1. Rates of crude 10-year mortality were significantly lower in E-E, N-E, and S-E compared to W-E and N-A.

2. The differences in 10-year mortality remained significantly lower with N-E and S-E even after adjustment for confounding factors.

3. However, when comparing PCI to CABG in the five geographic regions, there were no statistically significant interactions between the geographic disparity in pre- and peri-procedural characteristics and all-cause mortality.

In the era of globalization, knowledge and understanding of geographic disparity are of paramount importance for the correct interpretation of global studies.

Funding Acknowledgement

Type of funding sources: Foundation. Main funding source(s): The German Foundation of Heart Research (Frankfurt am Main, Germany)

Impact of left ventricular ejection fraction on 10-year mortality after percutaneous coronary intervention or coronary artery bypass grafting

Backgrounds

The impact on vital prognosis at very long-term of percutaneous coronary intervention (PCI) and coronary artery bypass grafting (CABG) in patients with reduced ejection fraction (EF) remains to be elucidated.

Objective

To investigate the impact of left ventricular ejection fraction (LVEF) on 10-year mortality after PCI and CABG in the SYNTAX trial.

Methods

In the SYNTAXES study, 1,800 randomized patients were categorized into three groups according to the current guidelines; (1) reduced EF (rEF; LVEF ≤40%), (2) mildly reduced EF (mrEF; LVEF 41–49%), (3) preserved EF (pEF; LVEF ≥50%). The primary endpoint was 10-year all-cause mortality. Event rate up to 10 years was estimated according to the Kaplan-Meier method, and the log-rank test was performed to examine the differences among LVEF subgroups. The SYNTAX score 2020 (SS-2020) was compared between the patients with reduced (LVEF &lt;50%) and preserved EF (LVEF ≥50%) in order to better refine their respective personalized vital prognosis and assess in cross-validation the value of the risk score.

Results

The population was stratified as rEF (n=168), mrEF (n=179), and pEF (n=1453). Ten-year all-cause mortality were 44.0% vs. 31.8% vs. 22.6% (P&lt;0.001), in patients with rEF, mrEF and pEF, respectively. The significant interaction was not identified between LVEF classification and treatment (P interaction = 0.183). In patients with rEF, there was a tendency toward higher mortality in PCI group than CABG (52.9% vs 39.6%, P=0.054), and no significant differences in patients with mrEF (36.0% vs. 28.6%, P=0.273) and pEF (23.9% vs. 22.2%, P=0.275). According to the SS-2020, PCI was a relatively safe modality of revascularization in 37.8% of the patients with reduced EF (LVEF &lt;50%). In the population with preserved EF (LVEF ≥50%), the proportion of patients eligible to PCI with predicted equipoise in mortality with CABG was 57.5%.

Conclusion

LVEF could an important factor for determining the revascularization treatment in patients presenting with complex coronary artery disease. Calculation of individualized 10-year prognosis using the SS-2020 may be a viable option in decision-making.

Funding Acknowledgement

Type of funding sources: None.

Catheter ablation of persistent atrial fibrillation with heart failure improves hemodynamic status without deteriorating renal function in the elderly

Background/Introduction

Atrial fibrillation (AF) and heart failure (HF) frequently coexist in the elderly people, leading to worse clinical outcomes. HF with preserved ejection fraction (HFpEF) is the most common form of HF in the elderly, particularly in women, associated with AF. Ablation of AF in younger patients with HF with reduced EF (HFrEF) has become an established treatment option. However, clinical impact of ablation for persistent AF accompanying with HF in the elderly remains unclear.

Purpose

This study aimed to evaluate the effect of catheter ablation of persistent AF with heart failure in the elderly.

Methods

Consecutive 70 patients who underwent catheter ablation of persistent AF accompanying with HF (NYHA class&gt; II, mean LVEF 51.7%) in our institution were retrospectively analyzed with regards to their 1-year clinical outcomes, HF markers such as BNP, renal function and transthoracic echocardiographic findings. Patients were dichotomized by age of 75-year-old (31 elderly vs 39 younger subjects) and separately analyzed.

Results

Mean age of the studied population was 70.5 year-old; 79.6±3.8 in the elderly group and 63.2±8.5 in the younger group. The elderly patients were more frequently females (45% vs 21%). Longstanding persistent AF was observed in 32% in the elderly and 28% in the younger group. Circumferential pulmonary vein isolation (PVI) was performed in all patients, with additional ablations of liner lesions and/or non-PV foci as needed. PVI alone was observed in 54.8% in the elderly and 41% in the younger group. There were no serious complications associated with the procedure. During 1 year after ablation, recurrence of AF was observed in 15 patients [6/31 (19%) in the elderly, 9/39 (23%) in the younger]. Readmission due to HF was observed in only 1 patient in the elderly and 2 patients in the younger group (3% vs. 5%, respectively). Cardiovascular events were observed in 3 patients [2/31 (6%) in the elderly, 1/39 (3%) in the younger], but there was no death. The BNP level as well as the NYHA class significantly decreased at 1-year follow-up compared to baseline in the both groups (Figure A and B). There was no change in serum creatinine level in the both groups (Figure C). The left atrial dimension and the LA volume index decreased at 1-year follow-up in the both groups (Figure D and E). The LVEF improved only in the younger group (Figure F).

Conclusions

Ablation of persistent AF in the elderly with HF (mostly with preserved EF) was associated with hemodynamic and functional improvements without deteriorating renal function in a mid-term, which was mostly comparable to the results in the younger.

Funding Acknowledgement

Type of funding sources: None.

Appropriateness of the modality of revascularization according to the SYNTAX 2020 in the FASTTRACK CABG study

Objectives

To compare the modality of revascularization selected by the local heart team to the one recommended by the core laboratory according to the SYNTAX score 2020 amongst patients with three-vessel disease (3VD) with or without left main disease (LMCAD), who were allocated to CABG planned and solely guided by coronary computerized tomographic angiography in the FASTTRACK CABG trial.

Background

Personalized long term vital prognosis plays a key role in deciding between PCI and coronary artery bypass grafting (CABG) in patients with complex coronary artery disease.

Methods

In an interim analysis requested by the Data Safety Monitoring Board the treatment recommendations according to the SYNTAX 2020 were prospectively assessed in 57 consecutive patients (half of the planned population in this First in Man) by a core laboratory and compared to the decision of the “on site” heart team.

Results

According to SS-2020, the predicted absolute risk difference (ARD) in mortality between the virtual PCI treatment population and the CABG treatment group, which can be considered a virtual surrogate for the average treatment effect, increased with the duration of follow up, from 4.8±3.5% at 5 years to 8.8±5.1% at 10 years (Table 1). The ARD of less than 0% in mortality at 5-year in favour of PCI was only documented in two patients while the 55 remaining patients had a predicted survival benefit over PCI if receiving CABG. However, based on a novel threshold of equipoise (ARD &lt;4.5%) recently validated in a contemporary registry of 3VD and LMCAD, CABG was mandatory in 26 (45.6%) patients, whereas PCI or CABG could have been equally selected in 31 (54.4%) patients (Figure 1).

Conclusions

According to the SYNTAX Score 2020 there was a strict observance of the CABG treatment recommendation in the first 57 consecutive patients with 3VD or LMCAD, screened on site in the FAST TRACK CABG trial. The more lenient selection criteria derived from the contemporary regitry will have to be tested propectively. Application of artificial intelligence with expanded collection of baseline characteristics, scientific endorsement and regulatory enforcement as well as further prospective evaluation are the challenges of future decision-making scores, that should be ultimately shared with the patients.

Funding Acknowledgement

Type of funding sources: None.

Murray law-based quantitative flow ratio for assessment of left main bifurcation derived from a single fluoroscopic angiographic view as compared to FFRCT

Background

In patients with complex CAD, the presence of left main (LM) disease is an important prognostic factor in assessing the risk balance between PCI and CABG. Functional assessment has become standard of care to evaluate the significance of coronary stenosis and to justify the performance of PCI in the contemporary practice. FFRCT is a well-established method based on 3D reconstruction of coronary artery derived from CCTA. The Murray law-based quantitative flow reserve (μQFR) is a novel computational method of invasive angiography relying on a single angiographic view that takes into account side branches diameters to compute fractal flow division. The aim of the current analysis is to evaluate in patients with complex CAD the feasibility of μQFR in LM bifurcation and its diagnostic concordance with FFRCT. The impact of the optimal viewing angle defined by CCTA on the physiological assessment of the LM bifurcation using a single angiographic view was also evaluated.

Methods

In 299 consecutive patients with 3-vessel disease with or without LM coronary artery disease, up to 3 analyzable fluoroscopic projections per patient were analysed with μQFR retrospectively. FFRCT and μQFR were measured at 3 fiducial landmark points: i) point of LM bifurcation (POB); ii) proximal LAD 10 mm distal to POB; ii) proximal LCX 10 mm distal to POB. CCTA-based “optimal viewing angle” of LM bifurcation are computed by creating a 3-point closed spline involving the LM, LAD, and LCX at 5mm from the POB and subsequently by reconstructing the “en face” fluoroscopic viewing angle of the spline. The en face viewing angle provides an optimal assessment of the bifurcation geometry [1]. In terms of Rx gantry angulation, the closest angiographic projection to the optimal viewing angle derived from CCTA was defined as the “best fluoroscopic projection” for each patient.

Results

In 299 patients, 793 projections were analysed with μQFR and compared to FFRCT. Single view μQFR was analyzable in 100%. Correlation and agreement between μQFR and FFRCT for 793 projections in 299 patients are shown in Figure 1A, 2A. The Spearman's correlation coefficient showed moderate correlations at POB (r=0.481, p&lt;0.001) and LCX (r=0.584, p&lt;0.001), and strong correlation at LAD (r=0.642, p&lt;0.001). Correlation and agreement between μQFR and FFRCT for best projections from each patient are shown in Figure 1B, 2B. Correlations were improved in the best projections with the following Spearman's correlation coefficient: at POB (r=0.522, p&lt;0.001), LCX (r=0.622, p&lt;0.001), and LAD (r=0.695, p&lt;0.001).

Conclusion

Computation of μQFR from a single angiographic view has a high feasibility. Tailored optimal fluoroscopic view is essential for the physiological assessment of the LM bifurcation using a single angiographic view. Evaluation of diagnostic accuracy of μQFR warrants further analysis of the LMCAD after prospective planning of the optimal fluoroscopic view based on the selection of the best CCTA 3D view.

Funding Acknowledgement

Type of funding sources: None.

Angiographic derived physiological assessment after intervention for predicting 2-year vessel-oriented composite endpoints in Multivessel TALENT trial

Aims

The purpose of the study is to assess the treatment results in the first 200 patients in the ongoing Multivessel TALENT trial and to predict the vessel-oriented endpoint by assessing the quantitative flow ratio (QFR) post PCI in a central independent core laboratory.

Methods

In this prospective, randomized, 1:1 balanced, multi-centre, open-label trial, de novo multivessel coronary artery disease patients without left main disease are assigned to the sirolimus-eluting stent or everolimus-eluting stent arm. The percutaneous coronary intervention (PCI) is planned based on functional lesion evaluation by QFR provided by the Core laboratory and the PCI has to be optimized by intravascular imaging, optimal pharmacological treatment and prasugrel monotherapy.

Results

Mean age of the population was 66.6±14.7 years, and 78.1% of them were male. This population consists of 17.4% unstable angina and of 31.8% diabetic patients. Anatomical SYNTAX score was 18.8±9.1. Total 458 lesions were treated from September 2020 to December 2021. Left anterior descending artery accounts for 40.3%, bifurcation lesion was present in 40.8%, total occlusion in 4.2%. The average stent diameter and total stent length were 3.0±0.4mm and 38.7±22.4mm, respectively. Intravascular imaging was used in 92.8% of treated vessels (intravascular ultrasound 56.5%, optical coherent tomography 36.3%). Pre-PCI QFR was analysable in 435 vessels (0.59±0.21), and 5.5% of them were treated even though the pre-PCI QFR values were more than 0.8. Post-PCI QFR has been so far analysed in 303 vessels (0.93±0.11) and 79.5% of them achieved a post-PCI QFR equal or superior to 0.91. Based on the previous study [1], Two-year vessel-oriented composite endpoint (VOCE) was estimated to become 5.4% in the present study population (3.7% in the patient group that achieved post PCI QFR equal or superior to 0.91, while 12% in the patients who could not reach the threshold), which was almost equal to what is expected in the power calculation.

Conclusions

In the Multivessel TALENT trial, the large majority of the vessels treated (94.5%) complied with the hemodynamic criteria of recommended PCI as provided by the QFRs of the Core laboratory. Favourable post-PCI QFR (≥0.91) obtained in 80% of the patients let expected a favourable VOCE outcome of 5.4%.

Funding Acknowledgement

Type of funding sources: Public Institution(s). Main funding source(s): The National University of Ireland Galway

Comparison of the SYNTAX score 2020 based on Coronary Artery Computed Tomography (CCTA) with Invasive Coronary Angiography (ICA)

Introduction

The SYNTAX III REVOLUTION trial demonstrated that clinical decision-making between coronary artery bypass graft (CABG) and percutaneous coronary intervention (PCI) based on coronary artery computed tomography (CCTA) and predicting four years mortality according to the SYNTAX score II had a high agreement with the treatment decision derived from invasive coronary angiography (ICA). The agreement of the novel SYNTAX score 2020 (SS-2020) based on CCTA and ICA has not yet been evaluated in a prospective fashion.

Methods

This study included 54 consecutive patients in the ongoing FASTTRACK CABG trial that investigates decision making, planning and procedural CABG guidance based solely on CCTA and FFRct. All the patients underwent CCTA and ICA, and SS-2020 was calculated based on the results of anatomical SYNTAX score derived from either CCTA or ICA, and the respective scores were compared by using paired t-test.

Results

The mean age was 67.3±9.7, and 48 were men (88.9%). Anatomical SYNTAX score derived from CCTA was assessed in the 54 cases (analysability 100%). Anatomical SYNTAX scores based on CCTA and ICA were 34.3±9.3, and 35.5±11.3, respectively (P=0.480). As shown in the table predicted 5 years major adverse cardiac and cerebrovascular events (MACCE) following either PCI or CABG, as well as predicted 10 years mortality following CABG differed significantly. However the absolute risk differences (ARD) in 5 years MACCE and 10 years mortality following either PCI or CABG, were comparable.

Conclusions

High agreements were confirmed in the calculations of anatomical SYNTAX scores with CCTA and ICA. Despite significant differences in predicted MACCE rates at 5 years and mortalities at 10 years, the ARD in MACCE rates and mortality were comparable. In terms of treatment decision-making, SS-2020 calculations based on CCTA is a non-invasive predictive tool comparable to the one based on ICA.

Funding Acknowledgement

Type of funding sources: None.

Aggressive combined pharmacotherapy for heart failure reduces new onset atrial fibrillation

Backgrounds

Heart failure (HF) is a risk factor for new onset atrial fibrillation (AF), and the new onset AF is associated with a worse prognosis in HF patients. It has been reported that renin-angiotensin system inhibitor (RASi), β-blocker and mineral-corticoid receptor antagonist (MRA) prevent the new onset AF in HF patients. However, the effect of combined pharmacotherapy including angiotensin receptor neprilysin inhibitor (ARNI) and sodium glucose co-transporter 2 inhibitor (SGLT2i) on AF is unknown. We investigated the impact of contemporary regimen of combined pharmacotherapy for HF (RASi/ARNI+β-blocker+MRA+SGLT2i) on new onset AF.

Methods and results

We retrospectively studied rEF and mrEF patients without AF admitted to our hospital due to decompensated HF between 2015 and 2021 (n=366). Long-term (The mean follow-up was 635±421 days) incidence of new onset AF was investigated with regard to medical therapies. Patients were divided into 2 groups; patients with ≤2 HF drugs (n=181) and patients with ≥3 HF drugs (n=185). Patients with ≤2 HF drugs group were older (77.3 vs 67.0 years old, P&lt;0.001), had a poorer renal function (Cre: 1.66 vs 1.09 mg/dl, P&lt;0.001), and had a higher rate of ischemic heart disease (52 vs 38%, P=0.009), whereas left ventricular systolic function was better (EF: 31.9 vs 27.3%, P&lt;0.001). There were 19 (10.5%) new onsets AF in the ≤2 HF drugs group, whereas only 7 (3.8%) had new onsets AF in the ≥3 HF drugs group (HR 0.36, 95% CI 0.15–0.85, P=0.01). All-cause death and hospitalization for HF were fewer in the ≥3 HF drugs group. A multivariate analysis revealed that ≥3 HF drugs use was an independent negative predictor of new onset AF (HR 0.37, 95% CI 0.15–0.93, P=0.03). Even after a propensity score matching of the clinical variables, the incidence of new onset AF was consistently fewer in the ≥3 HF drugs group (HR 0.36, 95% CI 0.13–0.99, P=0.04). Finally, patients with new onset AF had a higher rate of hospitalization for HF in the studied population (HR 9.68, 95% CI 5.67–16.5, P&lt;0.01).

Conclusion

Aggressive combined pharmacotherapy for HF may be associated with fewer new onset AF in patients with HF.

Funding Acknowledgement

Type of funding sources: None.

Comprehensive Analysis of Molecular Biologic Characteristics of Pancreatic Ductal Adenocarcinoma Concomitant with Intraductal Papillary Mucinous Neoplasm

BACKGROUND

Pancreatic ductal adenocarcinoma (PDAC) concomitant with intraductal papillary mucinous neoplasm (IPMN) is defined as PDAC occurring apart from IPMN. This study comprehensively investigated the molecular biologic characteristics of PDAC concomitant with IPMN in major genetic alterations, tumor microenvironment, and prognosis by contrast with those of conventional PDAC.

METHODS

The study retrospectively reviewed the data of 158 surgically resected PDAC patients. The driver gene alteration status (KRAS, TP53, CDKN2A, SMAD4, and GNAS) together with the immune and fibrotic status in tumor was evaluated. The prognosis of PDAC concomitant with IPMN and that of conventional PDAC also were compared.

RESULTS

No statistically significant difference was found between PDAC concomitant with IPMN and conventional PDAC in the alteration frequency analysis of the major driver genes and the immune and fibrotic status in the tumor microenvironment. Overall survival and disease-free survival between patients who had PDAC concomitant with IPMN and those who had conventional PDAC did not show statistically significant differences in propensity-matched subjects. Furthermore, the co-existence of IPMN was not a poor prognostic factor in the multivariable-adjusted Cox proportional hazards model (hazard ratio, 0.95; 95 % confidence interval, 0.51-1.78).

CONCLUSIONS

In this study, PDAC concomitant with IPMN had tumor characteristics similar to those of conventional PDAC in terms of the major driver gene alterations, tumor microenvironment, and prognosis.

Applying patient characteristics, stent-graft selection, and pre-operative computed tomographic angiography data to a machine learning algorithm: Is endoleak prediction possible?

INTRODUCTION

This study aims to predict endoleak after endovascular aneurysm repair (EVAR) using machine learning (ML) integration of patient characteristics, stent-graft configuration, and a selection of vessel lengths, diameters and angles measured using pre-operative computed tomography angiography (CTA).

METHODS

We evaluated 1-year follow-up CT scans (arterial and delayed phases) in patients who underwent EVAR for the presence or absence of an endoleak. We also obtained data on the patient characteristics, stent-graft selection, and preoperative CT vessel morphology (diameter, length, and angle). The extreme gradient boosting (XGBoost) for the ML system was trained on 30 patients with endoleaks and 81 patients without. We evaluated 5217 items in 111 patients with abdominal aortic aneurysms, including the patient characteristics, stent-graft configuration and vascular morphology acquired using pre-EVAR abdominal CTA. We calculated the area under the curve (AUC) of our receiver operating characteristic analysis using the ML method.

RESULTS

The AUC, accuracy, 95% confidence interval (CI), sensitivity, and specificity were 0.88, 0.88, 0.79-0.97, 0.85, and 0.91 for ML applying XGBoost, respectively.

CONCLUSIONS

The diagnostic performance of the ML method was useful when factors such as the patient characteristics, stent-graft configuration and vessel length, diameter and angle of the vessels were considered from pre-EVAR CTA.

IMPLICATIONS FOR PRACTICE

Based on our findings, we suggest that this is a potential application of ML for the interpretation of abdominal CTA scans in patients with abdominal aortic aneurysms scheduled for EVAR.

AB0971 Relationship between walking speed and lower limb skeletal muscle mass in patients with knee joint disorders

Background

Knee joint disorder is one of the factors causing frailty in the elderly, which is associated with a decrease in walking speed.

Objectives

We measured the walking speed of patients scheduled to undergo primary total knee arthroplasty (TKA) and examined factors correlated with walking speed.

Methods

The patients with knee disorders scheduled to undergo knee arthroplasty at our hospital between July 2020 and May 2021 were included. They were assessed for basic attributes, clinical assessment including Kness Society Score (KSS), degree of pain on walking by visual analogue scale (VAS), range of motion (ROM), and also leg skeletal muscle mass index (SMI; whole-body mode DXA), quadriceps strength by dynamometer with written consent (UMIN ID: 000040940). And Japanese Cardiovascular Health Study criteria for frailty, and sarcopenia by Asian Working Group for Sarcopenia 2019 criteria were evaluated.

Results

Demographic data of 83 patients (65 women, mean age 74.9 years) included in this study was shown in Table 1. The distribution in frailty is 36.2% and that in sarcopenia is 7.3%. Most of the patients with frailty with knee disorder did not suffer from sarcopenia. A multivariate analysis was conducted with walking speed as the objective variable and the dependent variables as age, gender, pain VAS on walking, KSS, leg SMI, quadriceps strength, and ROM. The results showed that age and ROM in flexion were significantly and independently associated with walking speed (P=0.01, 0.03). Gender, pain VAS on walking, KSS, leg SMI, quadriceps strength, and ROM in extension were not significantly associated with walking speed (P=0.92, 0.11, 0.11, 0.52, 0.85, 0.52).

Conclusion

Among the patients with knee disorders immediately before arthroplasty, frailty was not caused by sarcopenia. Age was found to be the most correlated factor with walking speed, and walking speed became slower with age. In addition, poor flexion angle was also the factor for delayed walking speed, but it did not correlate with lower limb skeletal muscle mass or quadriceps strength. In this study pain on walking was not significant factor for walking speed, because it was observed in most of all cases.

FactorGroup　disease (n)osteoarthritis78 (94%)　rheumatoid arthritis5 (6.0%)body mass index (kg/m2)　25.54 (4.11)pain VAS on walking　37.08 (26.35)total Knee Society Score　77.66 (27.85)range of motion (degree)flexion119.46 (12.88)　extension-9.58 (6.59)quadriceps power (N)　122.00 [53.00, 350.00]waling speed (m/sec)　0.95 (0.33)grip power (kg)　20.24 (6.97)skeletal muscle mass index (kg/m2)appendicular6.50 [4.92, 9.85]　lower limb5.06 [3.76, 7.56]Frailty (n)none10 (12.5%)Pre-frail41 (51.2%)　frail29 (36.2%)Sarcopenia (n)none76 (92.7%)sarcopenia4 (4.9%)　severe sarcopenia2 (2.4%)

mean (standard deviation)

; median [min max]

Disclosure of Interests

None declared

OP0090 PRECLINICAL STUDIES OF A NOVEL CATHEPSIN C INHIBITOR IN MPO-ANCA-ASSOCIATED VASCULITIS MODEL

Background

MPO-ANCA-associated vasculitis (MPO-AAV) is a systemic small vessel vasculitis with the production of MPO-ANCA in the serum. This disease develops necrotizing and crescent glomerulonephritis (NCGN) and peritubular capillaritis-mediated interstitial damages in the kidneys, and pulmonary hemorrhage due to capillaritis in the lungs. Recent studies have revealed that neutrophil extracellular traps (NETs) induced by MPO-ANCA are critically involved in its pathogenesis,1 and neutrophil elastase (NE) plays an essential role in the formation of NETs.2 Cathepsin C (CatC) functions as a key enzyme in the activation process of several neutrophil serine proteases (NSPs) such as NE, proteinase 3 and cathepthin G by converting the inactive forms of the NSPs to the active forms by digesting dipeptides at the N-terminus of the enzymes.3

Objectives

Although glucocorticoids and immunosuppressive drugs used as the standard of cares can lead remission in MPO-AAV patients, there are remaining unmet medical needs such as severe side effects, resistance to the treatment and relapse. Therefore, development of new therapeutic strategies is awaited. The aim of this study is to demonstrate the efficacy of MOD06051, a novel CatC inhibitor, against MPO-AAV, using an MPO-AAV rat model established previously.4

Methods

In vitro studies: Cathpsins and NE inhibitory activity was measured using recombinant enzymes and fluorescent substrates. Cellular NE activity in the granulocytes differentiated from the primary human bone marrow-derived hematopietic stem cells under the presence or absence of MOD06051 was determined using fluorescent substrates.

In vivo studies: 4-week-old Wistar Kyoto (WKY) rats were immunized with human MPO according to Little’s protocol.4 The rats were divided into three groups (n=8 in each group), and vehicle (0.5% methylcellulose) or MOD06051 (0.3 or 3 mg/kg bid) was orally administered every day for 42 days. All rats were euthanized at the end of the study for serological and histological evaluations.

Results

In vitro studies: MOD06051 inhibited the enzymatic activity of human recombinant CatC with an IC50 value of 1.5 nM, and no other cathepsins nor NE inhibition was observed at 10 μM. The NE activity in primary human granulocytes was suppressed by MOD06051 with an IC50 value of 18 nM.

In vivo studies: MPO-ANCA was induced in all groups at the same level. The percentage of affected glomeruli including those with NCGN, NET-forming neutrophils in the peripheral blood and glomeruli, and glomerular neutrophil counts were significantly suppressed by MOD06051 treatment in a dose-dependent manner. Furthermore, hematuria score, urinary NGAL (Neutrophil Gelatinase-Associated Lipocalin), tubular erythrocyte cast counts, and pulmonary hemorrhage foci were significantly decreased in the 3 mg/kg of MOD06051 treated group with the similar trends in 0.3 mg/kg group.

Conclusion

MOD06051 showed sepcific inhibition of CatC activity. This compound suppressed the serine proteases activation in primary human neutrophils and NET formation in the MPO-AAV model rats, resulting in amelioration of MPO-ANCA-induced tissue destruction, including NCGN and tubular interstitial damages in the kidneys, and disorder of alveolar septal capillaries in the lungs. MOD06051 appears to be a promising agent for treatment of MPO-AAV patients.

References

[1]Nakazawa D, et al. Nat Rev Rheumatol 15: 91-101, 2019.

[2]Papayannopoulos V, et al. J Cell Biol 191: 677-691, 2010.

[3]Korkmaz B, et al. Pharmacol Ther 190: 202-236, 2018.

[4]Little MA, et al. Am J Pathol 174: 1212-1220, 2009.

Disclosure of Interests

Akihiro Ishizu Grant/research support from: Modulus Discovery, Inc., Mai Taniguchi: None declared, Suishin Arai: None declared, Yuka Nishibata Grant/research support from: Modulus Discovery, Inc., Sakiko Masuda Grant/research support from: Modulus Discovery, Inc., Utano Tomaru: None declared, Takafumi Shimizu Shareholder of: Modulus Discovery, Inc., Employee of: Modulus Discovery, Inc., William Sinko Shareholder of: Modulus Discovery, Inc., Employee of: Modulus Discovery, Inc., Tadashi Nagakura Shareholder of: Modulus Discovery, Inc., Employee of: Modulus Discovery, Inc., Yoh Terada Shareholder of: Modulus Discovery, Inc., Employee of: Modulus Discovery, Inc.

Effect of injection duration on contrast enhancement during cardiac computed tomography angiography in newborns and infants

INTRODUCTION

To investigate how changing the injection duration at cardiac computed tomography angiography (CCTA) affects contrast enhancement in newborns and infants.

METHODS

Included were 142 newborns and infants with confirmed congenital heart disease who underwent CCTA between January 2015 and December 2018. In group 1 (n = 71 patients), the injection duration was 8 s; in group 2 (n = 71) it was 16 s. Our findings were assessed by one-to-one matching analysis to estimate the propensity score of each patient. We compare the CT number for the pulmonary artery (PA), ascending aorta (AAO), left superior vena cava (SVC), AAO and PA enhancement ratio, and the scores for visualization between the two groups.

RESULTS

In group 1, median CT number and ranges was 345 (211-591) HU in the AAO, 324 (213-567) HU in the PA, and 62 (1-70) HU in the SVC. These values were 465 (308-669) HU, 467 (295-638) HU, and 234 (67-443) HU, respectively, in group 2 (p < 0.05). The median score for volume-rendering visualization on 3D images of the CCTA was 2 in group 1 and 3 in group 2; the score for visualization of the left SVC of the maximum intensity projection images was 2 in group 1 and 3 in group 2 (p < 0.05). The CT number for the AAO and PA enhancement ratio was 15.2 in group 1 and 9.2 in group 2 (p < 0.05).

CONCLUSION

The 16-sec injection protocol yielded significantly higher CT numbers for the AAO, PA, and the SVC than the 8-sec injection protocol; the visualization scores were also significantly higher in group 2.

IMPLICATIONS FOR PRACTICE

In newborns and infants, the longer injection time for CCTA yields stable and higher contrast enhancement at identical CM concentrations.

Enhancement rate of venous phase to portal venous phase computed tomography and its correlation with ultrasound elastography determination of liver fibrosis

INTRODUCTION

This study aimed to compare the correlation between the computed tomography (CT) enhancement rate of the venous to portal venous phase (VP-ER) and the extracellular volume (ECV) fraction with shear-wave ultrasound elastography (USE) findings in patients with liver fibrosis.

METHODS

We included 450 patients with clinically suspected liver cirrhosis who underwent triphasic dynamic CT studies and USE. We compared the USE results with the unenhanced CT phase, with enhancement in the hepatic artery phase (HAP), portal venous phase (PVP), and venous phase (VP), and with the ECV fraction and the VP-ER. We also compared the area under the curve (AUC) of the receiver operating characteristic (ROC) curve of the ECV fraction and VP-ER with that of the values obtained with USE.

RESULTS

The VP-ER was the most highly correlated with the liver stiffness value determined with USE (Pearson's correlation coefficient: r = 0.37), followed by enhancement in the PVP (r = -0.25), CT number on unenhanced CT scans (r = -0.22), the ECV fraction (r = 0.19), enhancement in the VP (r = 0.059), and enhancement in the HAP (r = -0.023) (all p < 0.01). The VP-ER showed a significantly higher AUC than the ECV fraction (0.75 vs 0.62) when the liver stiffness was >15 kPa in USE studies (p = 0.04).

CONCLUSION

Compared to the ECV fraction, the VP-ER is more useful for predicting all degrees of liver fibrosis on routine triphasic dynamic CT images.

IMPLICATIONS FOR PRACTICE

Although improvement is needed, the VP-ER has a higher diagnostic ability for liver fibrosis than the ECV fraction in clinical practice.

Efficacy of the spiral flow generating extended tube during paediatric CCTA

INTRODUCTION

To compare the computed tomography (CT) number for paediatric cardiac computed tomography angiography (CCTA) and visualisation score of the three-dimensional (3D) images using the conventional T-shaped extended tube (T-tube) and spiral flow-generating extended tube (spiral-tube) connected between the contrast injector and cannula.

METHODS

In total, 108 patients suspected to have congenital heart disease (CHD) were considered for inclusion. We utilised the T-tube for intravenous contrast and spiral-tube in 54 patients each. Observers individually inspected randomized volume rendering images of the internal thoracic artery, each acquired from the with or without spiral-tube groups, using a four-point scale. We compared the mean CT number of the ascending aorta (AAO) and pulmonary artery (PA), contrast noise ratio (CNR), CT number for the AAO and PA enhancement ratio, and the visualisation scores between the groups.

RESULTS

There were no significant differences in patient characteristics between the with or without spiral-tube groups (p > 0.05). The mean CT number ±standard deviation for the AAO and PA, and the CNR without or with spiral-tube groups were 441.2 ± 89.2 and 489.8 ± 86.1 HU for the AAO, 436.3 ± 100.6 and 475.3 ± 85.2 HU for the PA, and 9.5 ± 2.2 and 10.8 ± 2.4 for the CNR, respectively (p < 0.05). In the spiral-tube group, the CT number, CNR, and visualisations score of the 3D images were significantly higher for the AAO and PA than those in the T-tube group (p < 0.05).

CONCLUSION

The spiral-tube proved to be beneficial in improving the CT number for the AAO and PA, CNR, and visualisation score compared with the conventional T-tube during paediatric CCTA.

IMPLICATIONS FOR PRACTICE

The spiral-tube may allow the visualisation of smaller blood vessels than those visualised by the conventional T-tube for paediatric patients in CCTA.

Diagnostic performance of computed tomography digital subtraction angiography of the lower extremities during haemodialysis in patients with suspected peripheral artery disease

INTRODUCTION

With intra-arterial digital subtraction angiography (DSA) considered as the gold standard, we compared the diagnostic value of computed tomography angiography (CTA) and computed tomography-digital subtraction angiography (CT-DSA in hemodialysis (HD) patients suspected of having lower limb peripheral artery disease (PAD).

METHODS

In this retrospective study, we enrolled 220 HD patients with suspected PAD. CT-DSA images were obtained by subtracting unenhanced images from enhanced images. The research team calculated the area under the curve (AUC), sensitivity, specificity, positive and negative predictive value (PPV, NPV), and recorded the diagnostic accuracy between the CTA and CT-DSA images using the DSA as gold standard. Visual evaluation of calcifications in the peripheral arteries were also compared between CTA and CT-DSA images.

RESULTS

At the above-knee level, the CTA AUC [95% confidence interval (CI)] was 0.68 (CI 0.64-0.72), sensitivity and specificity were 60 and 81%, PPV and NPV were 85 and 53%, and accuracy was 67%. Below the knee, these values were 0.66 (CI 0.62-0.70), 71 and 79%, 79 and 47%, and 66%. For CT-DSA, above-knee, the AUC [95% CI] was 0.88 (CI 0.85-0.91), sensitivity and specificity were 84 and 92%, PPV and NPV were 89 and 97%, and accuracy was 93%. Below the knee, these values were 0.95 (CI 0.93-0.97), 95 and 93%, 96 and 83%, and 93%. The scores for the visualization of calcification in the peripheral arteries was significantly higher for CT-DSA than CTA (p < 0.05).

CONCLUSIONS

CT-DSA helps to assess stenotic PAD with high calcification in the lower extremities of HD patients.

IMPLICATIONS FOR PRACTICE

On CT-DSA images, the severity of vascular calcification can be assessed for HD patients suspected of PAD of the lower extremities.

The combined application of the contrast-to-noise index and 80 kVp for cardiac CTA scanning before atrial fibrillation ablation reduces radiation dose exposure

INTRODUCTION

To compare the radiation dose, diagnostic accuracy, and the resultant ablation procedures using 80 and 120-kVp cardiac computed tomography angiography (CCTA) protocols with the same contrast-to-noise ratio in patients scheduled for atrial fibrillation (AF) ablation.

METHODS

This retrospective study was performed following institutional review board approval. We divided 140 consecutive patients who had undergone CCTA using a 64-MDCT scanner into two equal groups. Standard deviation (SD) of the CT number was set at 25 Hounsfield units (HU) for the 120-kVp protocol. To facilitate a reduction in radiation dose it was set at 40 HU for the 80 kVp protocol. We compared the two protocols with respect to the radiation dose, the diagnostic accuracy for detecting left atrial appendage (LAA) thrombi, matching for surface registration, and the resultant ablation procedures.

RESULTS

At 120 kVp, the dose length product (DLP) was 2.2 times that at 80 kVp (1269.0 vs 559.0 mGy cm, p < 0.01). The diagnostic accuracy for thrombus detection was 100% using both protocols. There was no difference between the two protocols with respect to matching for surface registration. The protocols did not differ with respect to the subsequent time required for the ablation procedures and the ablation fluoroscopy time, and the radiation dose (p = 0.54, 0.33, and 0.32, respectively).

CONCLUSION

For the same CNR, the DLP at 80 kVp (559.0 mGy cm) was 56% of that delivered at 120 kVp (1269.0 mGy cm). There was no reduction in diagnostic accuracy.

IMPLICATIONS FOR PRACTICE

Maintaining CNR allows for a reduction in the radiation dose without reducing the image quality.

Acute pancreatitis in intraductal papillary mucinous neoplasms correlates with pancreatic volume and epithelial subtypes

BACKGROUND

Intraductal papillary mucinous neoplasm (IPMN) of the pancreas is associated with acute pancreatitis (AP) in some cases, however its causes have not been fully elucidated. We investigated the association of the incidence of AP with epithelial subtypes and pancreatic volume in IPMN.

METHODS

This retrospective study included 182 consecutive surgically resected IPMN patients between January 2000 and December 2018. The relationship between the incidence of AP and epithelial subtypes of IPMN and pancreatic volume was investigated. Epithelial subtypes of IPMN were classified into gastric (G type: N = 116), intestinal (I type: N = 49), pancreatobiliary (PB type: N = 14), and oncocytic types (O type: N = 3). Pancreatic volume of the contrast-enhanced computed tomography scan was measured using Ziostation2 software. Histological pancreatic parenchymal atrophy was also evaluated.

RESULTS

AP occurred more frequently in I-types (I-type vs. G-type, 22.4% [11/49] vs 3.4% [4/116], P = 0.003) and PB-types (PB type vs. G-type, 35.7% [5/14] vs. 3.4% [4/116], P = 0.007) in comparison with G-types, which constituted the majority of the resected IPMNs. AP occurred more frequently in I-type patients with high pancreatic volumes (I-type with high pancreatic volume vs. I-type with low pancreatic volume, 37.0% [10/27] vs. 4.7% [1/21], P = 0.02). However, histological atrophy did not show an additional influence on the association between the incidence of AP and epithelial subtypes. The elevation of serum pancreatic enzymes was not significantly related to epithelial subtypes.

CONCLUSION

Epithelial subtypes and the degree of pancreatic volume may be closely associated with the incidence of AP in IPMN.

A Case in which an Intraductal Papillary Neoplasm of the Bile Duct Was Surgically Resected 12 Years after the Initial Diagnosis

A 66-year-old Japanese man was referred to our hospital with multiple giant liver cysts. The cysts had already been detected as multiple 3-cm cysts with small nodules at another hospital 12 years prior to this presentation. The cysts were diagnosed as an intraductal papillary neoplasms of the bile duct (IPNB) occupying the right lobe of the liver. Extended right lobectomy was performed. Based on the pathological findings, the tumor was diagnosed to be an oncocytic-type IPNB with minimal invasion. This experience suggests that the progression of IPNBs occur relatively slowly. The present case might provide important information for understanding the natural history of IPNBs.

Presence of low voltage area predicts atrial tachyarrhythmia inducibility with atrial burst pacing after pulmonary vein isolation

Background

Induction of atrial fibrillation (AF)/atrial tachycardia (AT) by atrial burst pacing following ablation procedure may reflect the presence of residual substrates in the atria that maintain AF. However, the relation between the inducibility and left atrial low voltage area (LVA) has not been established.

Methods

Fifty-nine patients (65 years old, 43 males) with persistent AF who underwent pulmonary vein isolation (PVI)-based ablation were studied. All patients underwent left atrial voltage mapping during sinus rhythm and atrial burst pacing after PVI. Atrial burst pacing was performed with 30-beat at an amplitude of 10V from the ostium of the coronary sinus; increasing from 240 to 320 ppm in steps of 20 ppm or failure to 1:1 atrial capture. Inducibility was defined as AF/AT lasting more than 5 minutes following burst pacing. Left atrial LVA and other co-variates were analyzed with regard to burst pacing positivity.

Results

AF/AT was induced by burst pacing in 23 patients (39%). Univariate analysis revealed that past history of stroke, CHADS2 score and presence of left atrial LVA were significantly associated with the inducibility of AF/AT. Multivariate analysis revealed that only the presence of LVA was associated with the inducibility (OR 1.5: per 10% increase; p=0.04). We focused on the relationship between the extent of LVA and burst positivity. AF/AT inducibility increased as low voltage area increased, and it was as high as 72.7% when low voltage area was more than 20% (P&lt;0.05). Interestingly, induced arrhythmia type was AT rather than AF when low voltage area was more than 20%.

Conclusions

Presence of left atrial LVA is an independent predictor of atrial tachyarrhythmia inducibility after PVI in patients with persistent AF. A large amount of low voltage area is related to AT inducibility rather than AF.

Extent of LVA and burst positivity

Funding Acknowledgement

Type of funding source: None

Early follow-up visit at outpatient care after discharge improves 2-year heart failure readmission rate and long-term prognosis in patients with decompensated heart failure

Background/Introduction

It has been reported that heart failure (HF) readmission has not declined even with current cardiology practice in the last 10 years. It has been also reported that HF readmission tends to occur shortly after discharge. This may be due to overwork and excessive salt intake after discharge. In other words, it is conceivable that patient factors are largely attributable, which should be intervene for better clinical outcomes.

Purpose

We hypothesized and investigated whether an early follow-up visit at outpatient care within 2 weeks after discharge affects the re-admission rate and prognosis in patients with decompensated HF.

Methods

We retrospectively investigated consecutive 407 hospitalized patients due to decompensated HF. After exclusion of 99 patients with in-hospital death, transfer to another hospital and readmission within 2 weeks after discharge, consecutive 308 out of 407 patients were investigated. Two-year clinical outcomes after discharge were collected and analyzed. An early follow-up was defined as an outpatient care visit within 2 weeks after discharge with the adjustment of drugs and/or the lifestyle guidance, if necessary. A setting of early follow-up in each patient was according to a physician's discretion.

Results

One hundred-twenty eight patients underwent early follow-up visits and other 180 patients were without it. An univariate analysis showed that the early follow-up was significantly associated with a lower HF readmission rate during 2 years (17.1% in the early follow-up group, 34.4% in the control group, p≤0.001, OR=0.397, 95% CI=0.230–0.685, Figure) and a 2-year composite adverse outcome (all cause death and HF readmission; 18.7% vs. 40.5%, p&lt;0.001, OR=0.332, 95% CI=0.196–0.563, Figure). To exclude possible relationships of other co-variable factors, we performed a multivariate analysis about the association with HF readmission rate and the 2-year composite adverse outcome (co-variate factors as follows are included; factors of which p-value was less than 0.1 and general confounding factors). The multivariate analysis showed that the early follow-up was independently associated with HF readmission during 2 years (p=0.002, OR=0.376, 95% CI=0.197–0.716) and the 2-year composite outcome (p&lt;0.001, OR=0.343, 95% CI=0.182–0.648). Finally, we characterized the practical interventions at outpatient care after discharge. Lifestyle guidance was done in all patients. However, medication adjustments were done in only 36.7% patients. Interestingly, whether or not a medication adjustment was done at the early follow-up visit was not associated with the HF readmissions (p=0.781).

Conclusions

The present study suggests that an early follow-up approach after discharge in decompensated HF patients may improve the long-term prognosis. These results were not dependent on whether a medication adjustment was performed or not. An early follow-up may help improve patient factors of HF worsening.

Main results

Funding Acknowledgement

Type of funding source: None

A case of high-grade pancreatic intraepithelial neoplasia diagnosed based on focal pancreatic parenchymal atrophy after acute pancreatitis

A 60-year-old male visited a previous hospital with upper abdominal pain. He was diagnosed with localized mild acute pancreatitis. Three months later, abdominal contrast-enhanced computed tomography showed focal parenchymal atrophy of the pancreas with distal pancreatic duct dilation. No obvious solid mass could be found at the site of the pancreatic duct stenosis on imaging examinations. Endoscopic retrograde pancreatography showed focal mild stenosis with distal pancreatic duct dilation in the tail of the pancreas. Carcinoma in situ of the pancreas was strongly suspected, especially based on the presence of focal atrophy of the pancreas around the site of stenosis of the main pancreatic duct and the distal pancreatic duct dilation. Laparoscopic distal pancreatectomy was performed. Histologically, high-grade pancreatic intraepithelial neoplasia was found in the epithelium of the stenotic main pancreatic duct and its branches. This case suggests that localized acute pancreatitis and focal atrophy of the pancreas with distal dilation of the pancreatic duct could be important clinical manifestations of pancreatic carcinoma in situ.

Low-dose rectal diclofenac does not prevent post-ERCP pancreatitis in low- or high-risk patients

BACKGROUND AND AIM

The most common adverse event following an endoscopic retrograde cholangiopancreatography (ERCP) procedure is post-ERCP pancreatitis (PEP). Rectal nonsteroidal anti-inflammatory drug (NSAID) administration has shown promise to reduce the risk of PEP in high-risk patients. However, in contrast to high-risk patients, the role of NSAID administration in patients with low risk remains controversial.

METHODS

We performed a prospective, single-center, single-blinded, two-arm parallel group, randomized controlled trial to clarify the efficacy of low dose (50 mg) rectal NSAID administration for preventing PEP in at-risk patients. Patients scheduled to undergo ERCP were randomized into two groups, those with and without rectal administration of diclofenac. Patients in the diclofenac group received 50 mg of rectal diclofenac 30 min before undergoing ERCP. The primary endpoint was rate of PEP.

RESULTS

A total of 303 were randomized into the study groups. Four patients declined participation following randomization, and another two were withdrawn. As a result, a total of 147 patients were assigned to the diclofenac group and 150 to the control group. The baseline and procedural characteristics were similar in both groups. The primary endpoint of PEP occurrence was seen in 13 of 297 patients (4.4%), including eight (5.4%) in the diclofenac group and five (3.3%) in the control group (P = 0.286). Additionally, those results were not significantly different when patients were classified as low or high risk.

CONCLUSIONS

Prophylactic low-dose rectal diclofenac did not reduce the incidence of PEP following ERCP in patients classified as low or high risk.

Prediction of pancreatic atrophy after steroid therapy using equilibrium-phase contrast computed tomography imaging in autoimmune pancreatitis

Background and Aims

Imaging tools for predicting pancreatic atrophy after steroid therapy in autoimmune pancreatitis (AIP) have not been established. As delayed equilibrium‐phase contrast enhancement in computed tomography (CE‐CT) may reflect interstitial fibrosis, we evaluated the ability of equilibrium‐phase CT imaging for predicting pancreatic atrophy.

Methods

Forty‐six steroid‐treated AIP patients who underwent contrast‐enhanced CT at our university hospital were included in this retrospective study. CT attenuation (Hounsfield units [HU]) values in noncontrast images (NC) and equilibrium‐phase images (EP) and the differences in HU values between NC and EP images (SUB) were measured. Pancreatic volume was measured in CE‐CT before (Vol_pre) and after (Vol_post) steroid therapy. The volume reduction rate was calculated. The relationships of CT values with pancreatic atrophy, Vol_post, volume reduction rate, and diabetes exacerbation were investigated.

Results

CT values in the EP and SUB images before steroid therapy were associated with pancreatic atrophy after steroid therapy (atrophy vs nonatrophy 114.5 ± 12.8 vs 99.5 ± 11.1, P = 0.0002; 70.9 ± 14.72 vs 57.2 ± 13.1, P = 0.003, respectively), but CT values in NC images were not (P = 0.42). CT values in EP and SUB images before steroid therapy were correlated with Vol_post (EP images r = −0.70, P = 0.002; SUB images r = −0.68, P = 0.03) and volume reduction rate after steroid therapy (EP images: r = −0.55, P < 0.0001; SUB images r = −0.45, P = 0.002). Diabetes exacerbation was associated with higher EP and SUB values (P = 0.009 and P = 0.04, respectively).

Conclusion

Equilibrium‐phase contrast CT imaging may facilitate prediction of pancreatic atrophy after steroid therapy in AIP.

Usefulness of medication instruction sheets for sharing information on cancer chemotherapy within the health care team

Patients receiving cancer chemotherapy may experience a number of potentially severe adverse drug reactions. It is crucial for all members of the health care team to monitor the effect of medicines on the patient to ensure the safety and efficacy of the chemotherapy. The present study prepared medication instruction sheets (MISs) on hematological malignancy and conducted a questionnaire survey to verify their usefulness among physicians, dentists, and nurses. MISs were prepared for 103 chemotherapy and 44 pretreatment regimens for hematopoietic stem cell transplantation in the Department of Hematology at Kyushu University Hospital. Eight questions were prepared to investigate whether MISs could help physicians, dentists, and nurses manage cancer chemotherapy more safely, effectively, and efficiently, as well as in the sharing of information. A total of 35 medical staff working in inpatient wards, including 8 physicians, 3 dentists, and 24 nurses, participated in the questionnaire survey. All of the staff responded to the questionnaire survey, which showed that the MISs were favorably accepted by the participants. There was no negative opinion on the management of chemotherapy using the MISs. The MIS was a useful tool for sharing information on cancer chemotherapy between patients and medical staff and for enabling efficient management, thereby improving the safety and efficacy of treatment.

Evaluation of serum IgE in peach-allergic patients with systemic reaction by using recombinant Pru p 7 (gibberellin-regulated protein)

BACKGROUND

Lipid transfer protein (LTP) is a major fruit allergen. It has, however, recently been revealed that the systemic reaction in peach-allergic patients is related not only to LTP (Pru p 3) but also to gibberellin-regulated protein (Pru p 7). We investigated recombinant Pru p 7 (rPru p 7) for its potential use in worldwide standardization for the diagnosis of peach allergy.

METHODS

Natural Pru p 7 (nPru p 7) was purified from peach crude extract using a monoclonal antibody affinity column. Complementary DNA for Pru p 7 was cloned and expressed in Escherichia coli and Pichia pastoris. Serum immunoglobulin (Ig) E in peach-allergic patients was examined by enzyme-linked immunosorbent assay (ELISA) using nPru p 7 and rPru p 7 (E. coli product: erPru p 7 and P. pastoris product: prPru p 7).

RESULTS

Peach-allergic patients (n=27) were diagnosed and categorized into oral reaction (n=10) or systemic reaction (n=17). The nPru p 7 positivity based on serum IgE levels was 52% in the systemic-reaction group and 0% in the oral-reaction group (P<0.05). In the systemic-reaction group, there was no significant difference in reactivity between nPru p 7 and prPru p 7, but the reactivity of erPru p 7 was significantly lower than those of nPru p 7 and prPru p 7 (P<0.05).

CONCLUSIONS

We found that prPru p 7 exhibited reactivity in ELISA comparable to that of nPru p 7 for the diagnosis of peach allergy with systemic reaction.

Flux-tunable heat sink for quantum electric circuits

Superconducting microwave circuits show great potential for practical quantum technological applications such as quantum information processing. However, fast and on-demand initialization of the quantum degrees of freedom in these devices remains a challenge. Here, we experimentally implement a tunable heat sink that is potentially suitable for the initialization of superconducting qubits. Our device consists of two coupled resonators. The first resonator has a high quality factor and a fixed frequency whereas the second resonator is designed to have a low quality factor and a tunable resonance frequency. We engineer the low quality factor using an on-chip resistor and the frequency tunability using a superconducting quantum interference device. When the two resonators are in resonance, the photons in the high-quality resonator can be efficiently dissipated. We show that the corresponding loaded quality factor can be tuned from above 10⁵ down to a few thousand at 10 GHz in good quantitative agreement with our theoretical model.

Chemokine (C-X-C motif) ligand 1 is a myokine induced by palmitate and is required for myogenesis in mouse satellite cells

AIM

The functional significance of the myokines, cytokines and peptides produced and released by muscle cells has not been fully elucidated. The purpose of this study was to identify a myokine with increased secretion levels in muscle cells due to saturated fatty acids and to examine the role of the identified myokine in the regulation of myogenesis.

METHODS

Human primary myotubes and mouse C2C12 myotubes were used to identify the myokine; its secretion was stimulated by palmitate loading. The role of the identified myokine in the regulation of the activation, proliferation, differentiation and self-renewal was examined in mouse satellite cells (skeletal muscle stem cells).

RESULTS

Palmitate loading promoted the secretion of chemokine (C-X-C motif) ligand 1 (CXCL1) in human primary myotubes, and it also increased CXCL1 gene expression level in C2C12 myotubes in a dose- and time-dependent manner. Palmitate loading increased the production of reactive oxygen species along with the activation of nuclear factor-kappa B (NF-κB) signalling. Pharmacological inhibition of NF-κB signalling attenuated the increase in CXCL1 gene expression induced by palmitate and hydrogen peroxide. Palmitate loading significantly increased CXC receptor 2 gene expression in undifferentiated cells. CXCL1 knockdown attenuated proliferation and myotube formation by satellite cells, with reduced self-renewal. CXCL1 knockdown also significantly decreased the Notch intracellular domain protein level.

CONCLUSION

These results suggest that secretion of the myokine CXCL1 is stimulated by saturated fatty acids and that CXCL1 promotes myogenesis from satellite cells to maintain skeletal muscle homeostasis.

Medial meniscus extrusion correlates with disease duration of the sudden symptomatic medial meniscus posterior root tear

INTRODUCTION

Medial meniscus posterior root tear (MMPRT) leads to abnormal biomechanics of the knee by inducing the medial meniscus extrusion (MME). However, a time-dependent increase of the MME is not fully elucidated in patients suffering from the acute MMPRT. The aim of this study was to investigate the relationships among disease duration of the MMPRT and severity of the MME. We hypothesized that MME measurement correlates with disease duration after a sudden onset of the minor traumatic MMPRT during the short-term follow-up period.

MATERIALS AND METHODS

Forty-six patients who had an accurate episode of the posteromedial painful popping were investigated. All the patients were diagnosed having a symptomatic MMPRT with magnetic resonance imaging (MRI) examinations. Absolute MME was measured using MRI scans within 12 months after painful popping events. A correlation coefficient between duration from injury to MRI examination and absolute MME was evaluated.

RESULTS

Mean absolute MME was 4.5±1.6mm (range, 1.1-8.8mm) on MRI measurements. A good correlation was observed between MME measurement and duration from injury to MRI examination (R²=0.612). The best-fit equation for predicting each value was: MME=0.014×disease duration+3.288mm.

DISCUSSION

This study demonstrated that absolute MME increases progressively within the short duration after the onset of symptomatic MMPRT. Our results suggest that preoperative MME assessment may be important in determining disease duration and treatment strategy of the MMPRT.

LEVEL OF EVIDENCE

Retrospective cohort study level IV.