Genetic characterization of Shigatoxigenic and enteropathogenic Escherichia coli O80:H2 from diarrhoeic and septicaemic calves and relatedness to human Shigatoxigenic E. coli O80:H2

AIM

The purpose of this work was to identify and genetically characterize enterohemorrhagic Escherichia coli (EHEC) and enteropathogenic E. coli (EPEC) O80:H2 from diarrhoeic and septicaemic calves in Belgium and to comparing them with human EHEC after whole genome sequencing.

METHODS AND RESULTS

Ten EHEC and 21 EPEC O80 identified by PCR between 2009 and 2018 from faeces, intestinal content and a kidney of diarrhoeic or septicaemic calves were genome sequenced and compared to 19 human EHEC identified between 2008 and 2019. They all belonged to the O80:H2 serotype and ST301, harboured the eaeξ gene, and 23 of the 29 EHEC contained the stx2d gene. Phylogenetically, they were distributed in two major sub-lineages: one comprised a majority of bovine EPEC whereas the second one comprised a majority of stx2d bovine and human EHEC.

CONCLUSIONS

Not only EPEC but also EHEC O80:H2 are present in diarrhoeic and septicaemic calves in Belgium and are genetically related to human EHEC.

SIGNIFICANCE AND IMPACT OF THE STUDY

These findings support the need to assess cattle as potential source of contamination of humans by EHEC O80:H2 and to understand the evolution of bovine and human EHEC and EPEC O80:H2.

Anti-PD1 checkpoint inhibitor therapy in acral melanoma: a multicenter study of 193 Japanese patients

BACKGROUND

Acral melanoma (AM) is an epidemiologically and molecularly distinct entity that is underrepresented in clinical trials on immunotherapy in melanoma. We aimed to analyze the efficacy of anti-programmed cell death 1 (anti-PD-1) antibodies in advanced AM.

PATIENTS AND METHODS

We retrospectively evaluated unresectable stage III or stage IV AM patients treated with an anti-PD-1 antibody in any line at 21 Japanese institutions between 2014 and 2018. The clinicobiologic characteristics, objective response rate (ORR, RECIST), survival estimated using Kaplan-Meier analysis, and toxicity (Common Terminology Criteria for Adverse Events 4.0.) were analyzed to estimate the efficacy of the anti-PD-1 antibodies.

RESULTS

In total, 193 patients (nail apparatus, 70; palm and sole, 123) were included in the study. Anti-PD-1 antibody was used as first-line therapy in 143 patients (74.1%). Baseline lactate dehydrogenase (LDH) was within the normal concentration in 102 patients (52.8%). The ORR of all patients was 16.6% (complete response, 3.1%; partial response, 13.5%), and the median overall survival (OS) was 18.1 months. Normal LDH concentrations showed a significantly stronger association with better OS than abnormal concentrations (median OS 24.9 versus 10.7 months; P < 0.001). Although baseline characteristics were similar between the nail apparatus and the palm and sole groups, ORR was significantly lower in the nail apparatus group [6/70 patients (8.6%) versus 26/123 patients (21.1%); P = 0.026]. Moreover, the median OS in this group was significantly poorer (12.8 versus 22.3 months; P = 0.03).

CONCLUSIONS

Anti-PD-1 antibodies have limited efficacy in AM patients. Notably, patients with nail apparatus melanoma had poorer response and survival, making nail apparatus melanoma a strong candidate for further research on the efficacy of novel combination therapies with immune checkpoint inhibitors.

Characteristic brain hypoperfusion by 99mTc-ECD single photon emission computed tomography (SPECT) in patients with the first-episode schizophrenia

Objective

In this study, we evaluated brain perfusion in patients with first-episode medicated schizophrenia using the new analytical method, statistical parametric mapping (SPM) applied to single photon emission computed tomography (SPECT).

Method

We performed SPECT with 99-Tc-ethyl cysteinate dimer (99mTc-ECD) of the brain and magnetic resonance imaging (MRI) in patients with schizophrenia (n = 30) and control subjects matched for age and gender (n = 37). A voxel-by-voxel group analysis was performed using SPM2 (Z > 3.0, P < 0.001, uncorrected for multiple comparisons).

Result

In comparison with control subjects, the volumes of the bilateral frontal areas were found to be decreased on MRI. Blood flow was found to be reduced in the bilateral temporal areas in the patients with schizophrenia on SPECT.

Conclusion

In this study, patients with first-episode schizophrenia appeared to have significant bilateral temporal hypoperfusion, although temporal volumes were not significantly decreased in comparison with control subjects. Abnormality of temporal lobe blood flow in schizophrenia may show that functional changes occur earlier than structural changes, and may assist in the diagnosis of schizophrenia.

P1753 Echocardiographic assessment of prosthetic aortic valve in children

Introduction

Although the diagnostic utility of Doppler-derived hemodynamic parameters of prosthetic aortic valve (PAV) for detecting prosthetic dysfunction has been demonstrated in adults, interpreting these parameters in children is difficult, as the relative size of PAV varies more greatly in them than in adults. We aimed to elucidate how the Doppler-derived hemodynamic parameters change as the PAV size decreases relative to the somatic growth of children.

Methods

We reviewed 11 echocardiographic examinations of 9 mechanical PAVs in 8 children. The median age at echocardiographic examination was 10.2 (0.5-17.7) years. Underlying diagnoses leading to aortic valve replacement were aortic regurgitation due to dysplastic aortic valve in 3 children, Marfan syndrome in 1, persistent truncus arteriosus in 1, and aortic stenosis associated with interrupted aortic arch/coarctation of the aorta in 3. The PAV functioned normally in all examinations. PAV size was 19 mm in 8 examinations and 17 mm in 3 examination, which was standardized to body surface area at the examination by calculating z-scores based on previously published normative data of aortic valve diameter. We assessed the Doppler-derived hemodynamic parameters, namely peak velocity, mean pressure gradient, and accerelation time of the transprosthetic flow, the velocity-time integral (VTI) ratio of the left ventricular outflow to the transprosthetic flow, and effective orifice area (EOA) of the PAV calculated by using the continuity equation. The Pearson correlation coefficients between the PAV size z-score and Doppler-derived hemodynamic parameters of the normally functioning PAVs were evaluated. A p-value of &lt;0.05 was considered statistically significant.

Results

All the Doppler-derived hemodynamic parameters except for EOA had a statistically significant correlation with PAV size z-score (Pearson correlation coefficients: peak velocity, -0.76; mean pressure gradient, -0.70; acceleration time, -0.66; and VTI ratio, 0.76). Multivariate analysis revealed that VTI ratio was the sole parameter that independently correlated with PAV size z-score.

Conclusions

VTI ratio, which is theoretically less dependent on cardiac preload than other hemodynamic parameters, strongly reflects BSA-indexed PAV size. Disproportionately decreased VTI ratio in relation to PAV size might indicate prosthetic obstruction in children with PAV.

Abstract P1753 Figure. Correlation of PAV size and VTI ratio

Combined Impact of Physical Frailty and Social Isolation on Rate of Falls in Older Adults

OBJECTIVES

The aim of this study was to examine the impact of the combination of physical frailty and social isolation on falling in community-dwelling older adults.

DESIGN

A cross-sectional study of data obtained at registration in a randomized control trial.

SETTING

Community-based study of participants recruited from Toyota, Japan.

PARTICIPANTS

380 community-dwelling older adults (47.9% women, mean age = 72.3 ± 4.6 years).

MEASUREMENTS

Participants were categorized as non-frail or pre-frail/frail based on the Fried frailty criteria (slowness, weakness, exhaustion, low activity, and weight loss). Social isolation was examined using the Lubben Social Network Scale (LSNS-6), and scores lower than 12 points indicated social isolation. Participants were divided into four groups depending on pre-frail/frail status and social isolation, and experiences of multiple falls over the past year were compared between the groups.

RESULTS

Participants were classified into robust (n = 193), physical frailty (PF; n = 108), social isolation (SI; n = 43), and PF with SI (PF+SI; n = 36) groups. A total of 38 (10.0%) participants reported multiple falls. Logistic regression analysis showed that PF and SI groups were not independently associated with falling (PF: OR 1.64, 95% CI 0.65-4.16, SI: OR 2.25, 95% CI 0.77-6.58), while PF+SI group was significantly associated with falling compared with the robust group (OR 3.06, 95% CI 1.00-9.34, p = 0.049) after controlling for confounding factors.

CONCLUSION

Our findings support the assertion that coexistence with physical frailty and social isolation were associated with falling in the older adults.

Energy of the ^{229}Th Nuclear Clock Isomer Determined by Absolute γ-ray Energy Difference

The low-lying isomeric state of ^{229}Th provides unique opportunities for high-resolution laser spectroscopy of the atomic nucleus. We determine the energy of this isomeric state by taking the absolute energy difference between the excitation energy required to populate the 29.2-keV state from the ground state and the energy emitted in its decay to the isomeric excited state. A transition-edge sensor microcalorimeter was used to measure the absolute energy of the 29.2-keV γ ray. Together with the cross-band transition energy (29.2  keV→ground) and the branching ratio of the 29.2-keV state measured in a recent study, the isomer energy was determined to be 8.30±0.92  eV. Our result is in agreement with the latest measurements based on different experimental techniques, which further confirms that the isomeric state of ^{229}Th is in the laser-accessible vacuum ultraviolet range.

P4512Impact of pulmonary artery catheter on all-cause death of patients with acute heart failure with preserved ejection fraction: Short-term results from the PURSUIT-HFpEF registry

Background

Appropriate pulmonary artery catheter (PAC) use may effectively decrease mortality in acute heart failure patients. The concept that the pulmonary artery catheter (PAC) is a valuable tool for hemodynamic monitoring when used in appropriately selected patients and by physicians trained well to interpret and apply the data correctly provided has not been evaluated adequately yet in acute heart failure patients with preserved ejection fraction (HFpEF).

Methods

The PERSUIT-HFpEF Registry is a prospective, observational, multicenter cohort study on prognosis of HFpEF in Japan. Patients hospitalized for heart failure (diagnosed by using Framingham criteria) who met both of the following criteria were enrolled: 1) a left ventricular ejection fraction of 50% or more as measured at the local site by echocardiography; 2) an elevated level of N terminal pro brain natriuretic peptide (NT proBNP) (400 pg per milliliter or more) or brain natriuretic peptide (BNP) (100 pg per milliliter or more). In the present study, we evaluated the impact of PAC on all-cause death of the patients with HFpEF. PAC use was left at the discretion of attending physicians.

Results

The PERSUIT-HFpEF Registry enrolled 486 patients (81±9 years, 259 females, mean follow-up duration 198±195 days). Of these, data of PAC usage was available in 434 patients. Patients were further stratified according to use of a PAC: PAC 153 patients vs. non-PAC 281 patients. Length of hospitalization was numerically shorter in the PAC group than in the non-PAC group [20.3±14.7 vs. 22.5±17.4 days, p=0.182]. Kaplan-Meier estimated 1-year all-cause death rate was significantly lower in the PAC group than in the non-PAC group (9.5% vs. 19.1%, p=0.019). PAC use was associated with significant risk reduction of all-cause death [hazard ratio (HR) 0.425, 95% confidence interval (CI), 0.203–0.890, p=0.023] in the crude analysis. The significant risk reduction still existed after multivariate adjustment including potential confounders [HR 0.427, 95% CI, 0.185–0.984, p=0.046]

Kaplan Meier analysis

Conclusions

In the real-world Asian registry data, PAC use was associated with the improved all-cause death rate, suggesting that the PAC might be a useful guidance tool for treatment of the patients with HFpEF.

Acknowledgement/Funding

Roche diagnostics FUJIFILM Toyama Chemical

P5649Impact of atrial fibrillation detected by implantable cardioverter-defibrillators on future stroke events in patients with heart failure

Background

Atrial fibrillation (AF) is the most common type of arrhythmia. AF-related stroke tends to be more severe, and the mortality rate is higher compared with stroke without AF. The definition of AF in patients with implanted cardioverter-defibrillators (ICDs) is not clear and the appropriate treatment guideline for patients with AF episode has not established yet. Recent ICDs have led to an improvement in the early detection of AF episodes, especially in patients who are asymptomatic. Previous studies showed that atrial high-rate episodes (AHREs) detected by cardiac implantable electronic devices are associated with embolic stroke events. However, little is known about the incidence of AF and stroke events in Japanese heart failure patients with an ICD.

Objective

The purpose of this study was to identify the incidence of embolic stroke events in heart failure patients with and without AF events detected by ICDs and examine the risk factors of embolic stroke events.

Methods

We retrospectively analyzed the database of our hospital. Every 6 months, AF events were checked by ICDs. AF30 was defined as AF episodes lasting for ≥30 seconds detected by ICDs. We examined the characteristics and incidence of embolic stroke events and investigated the relationship between AF30 and the incidence of embolic stroke events.

Results

We enrolled 215 consecutive patients who had no prior AF and took no anticoagulant in this study (follow-up period, 58±35 months; age, 62±15 years; male sex, 75%). The mean CHADS2 score and CHA2DS2-VASc score were 2.4±0.8 points and 3.8±1.2 points, respectively. The mean HAS-BLED score was 2.1±1.0 points. During the follow-up, 14 of 215 patients (6.5%) had embolic stroke events. Nine patients (5.8%/year) and 5 patients (0.65%/year) had embolic stroke events with and without AF30, respectively. The comparison of characteristics among patients with and without embolic stroke events was shown in Table. In multivariate logistic regression analysis, independent predictors for embolic stroke events were new-onset episode of AF30 (odd ratio [OR] 21, 95% confidence interval [CI] 4.8–120, P<0.0001) and an enlarged left atrium ≥40mm (OR 14, 95% CI 2.2–304, P=0.0029).

Conclusions

Embolic stroke events were common in Japanese heart failure patients with an ICD. AF30 and enlarged left atrium were the risk factors of embolic stroke events in this population. Therefore, when physicians detect new-onset AF in patients with an ICD, they should consider a comprehensive assessment of the risk and benefit of prescribing an anticoagulant.

P3705Impact of subclinical atrial fibrillation detected by cardiac implantable electronic devices on the risk of future embolic stroke events from Far East

Background

Atrial fibrillation (AF) is the most common type of arrhythmia. AF-related stroke tends to be more severe, and the mortality rate is higher compared with stroke without AF. The definition of AF in patients with cardiac implantable electronic devices (CIEDs) is not clear and the appropriate treatment guideline for patients with AF episode has not established yet. Recent CIEDs have led to an improvement in the early detection of AF episodes, especially in patients who are asymptomatic. Previous studies showed that atrial high-rate episodes (AHREs) detected by CIEDs are associated with embolic stroke events. However, little is known about the incidence of AF and stroke events in Japanese patients with CIEDs who have no prior AF and take no anticoagulant.

Objective

The purpose of this study was to identify the incidence of embolic stroke events in patients with and without AF events detected by CIEDs and examine the risk factors of embolic stroke events.

Methods

We retrospectively analyzed the database of our hospital. Every 6 months, AF events were checked by CIEDs. AF30 was defined as AF episodes lasting for ≥30 seconds detected by CIEDs. We examined the characteristics and incidence of embolic stroke events and investigated the relationship between AF30 and the incidence of embolic stroke events.

Results

We enrolled 348 consecutive patients who had no prior AF and took no anticoagulant in this study (follow-up period, 65±58 months; age, 70±16 years; male sex; 64%; defibrillator, 55%). The mean CHADS2 score and CHA2DS2-VASc score were 1.8±1.1 points and 2.8±1.5 points, respectively. The mean HAS-BLED score was 1.7±1.2 points. During the follow-up, 23 of 348 patients (6.6%) had embolic stroke events. Thirteen patients (4.1%/year) and 10 patients (0.63%/year) had embolic stroke events with and without AF30, respectively. The comparison of characteristics among patients with and without embolic stroke events was shown in Table. In multivariate logistic regression analysis, independent predictors for embolic stroke events were new-onset episode of AF30 (odd ratio [OR] 5.3, 95% confidence interval [CI] 2.2–13, P=0.0003) and an enlarged left atrium ≥40mm (OR 3.1, 95% CI 1.2–7.9, P=0.016).

Conclusions

Embolic stroke events were common in Japanese patients with CIEDs. AF30 and enlarged left atrium were risk factors of embolic stroke events in this population. Therefore, when physicians detect new-onset AF in patients with CIEDs, they should consider a comprehensive assessment of the risk and benefit of prescribing an anticoagulant.

P6154Association between n-3 and n-6 polyunsaturated fatty acids and plaque vulnerability by optical coherence tomography in acute myocardial infarction patients

Background

The values of n-3 and n-6 polyunsaturated fatty acids (PUFAs) like low eicosapentaenoic acid (EPA) /arachidonic acid (AA) ratio are known to be associated with cardiovascular events, however their relationship with coronary plaque vulnerability in acute myocardial infarction (AMI) is not revealed.

Purpose

We evaluated the relationship between n-3 and n-6 PUFAs and coronary plaque vulnerability assessed by optical coherence tomography (OCT) in AMI patients.

Methods

We investigated 79 AMI lesions (51 ST elevated myocardial infarction (STEMI) lesions and 28 non-STEMI lesions) that had undergone emergency percutaneous coronary intervention using OCT. Coronary plaque characteristics by OCT were compared with n-3 and n-6 PUFAs values which were measured on admission.

Results

Of all AMI lesions (n=79), 43 thin-cap fibroatheroma (TCFA) and 35 plaque rapture (PR) were detected by OCT. Lesions with TCFA had no significant relationship with n-3 and n-6 PUFAs values, whereas lesion with PR had significantly lower EPA values than those without (55.8±29.5 vs 74.3±37.1 μg/ml, p=0.018). Median low-density lipoprotein (LDL) cholesterol value was 117 (98–137) mg/dl and sub-analysis in patients who had lower LDL cholesterol values than median (n=39) revealed that EPA values were significantly lower in lesions with TCFA (56.3±30.9 vs 85.3±47.7 μg/ml, p=0.03). In STEMI patients, the values of EPA and EPA/AA ratio were significantly lower in lesions with TCFA (EPA: 55.5±22.8 vs 80.8±46.1 μg/ml, p=0.01; EPA/AA ratio: 0.34±0.16 vs 0.50±0.36, p=0.03). STEMI patients who had lower LDL cholesterol values <114 mg/dl of median (n=26), the values of EPA, EPA/AA ratio, and EPA+ docosahexaenoic acid (DHA) /AA ratio were significantly lower in lesions with TCFA (EPA: 51.4±20.7 vs 93.1±53.0 μg/ml, p=0.01; EPA/AA ratio: 0.37±0.16 vs 0.67±0.41, p=0.01; EPA+DHA/AA ratio: 1.13±0.41 vs 1.63±0.76, p=0.04). In STEMI patients with lower LDL cholesterol values, EPA/AA ratio positively correlated with fibrous cap thickness (Spearman, ρ=0.35, p=0.08). The cutoff value of EPA/AA ratio predicting the existence of TCFA was 0.52 (area under the curve 0.78, sensitivity 93.8%, specificity 70.0%, p=0.02).

Conclusion

This study demonstrated that n-3 and n-6 PUFAs values were associated with coronary plaque vulnerability by OCT in AMI patients, especially in STEMI. These results suggest that n-3 and n-6 PUFAs may be residual risk markers of severe acute cardiovascular events in patients with low LDL cholesterol values.