Probiotic viability in the gastrointestinal tract in a randomised placebo controlled trial: combining molecular biology and novel cultivation techniques

Understanding the viability of ingested probiotics within the gastrointestinal tract is essential for evaluating their efficacy and deciphering their mechanisms of action. Detecting Bifidobacterium longum subspecies longum BB536 is particularly challenging owing to its indistinguishability from the naturally abundant B. longum species in the human gut. We aimed to address this challenge by developing a selective culture medium for B. longum BB536 and employing a propidium monoazide-quantitative polymerase chain reaction (PMA-qPCR) method to verify the survival of the probiotic after consumption. To achieve this, we designed a novel lactose-mupirocin-trimethoprim (LMT) medium that facilitates the cultivation of B. longum BB536 under anaerobic conditions at 42 °C. We screened 52 healthy adults and enrolled 39 who met the eligibility criteria. The participants were randomised into two groups, with 34 completing the protocol: 17 received commercial yogurt containing B. longum BB536 (9.30 log10 cfu/day) and 17 received a placebo. Prior to the intervention, B. longum BB536 was undetectable in all participants. However, following supplementation, LMT culturing identified viable B. longum BB536, with average counts of 6.33 ± 0.69 log10 cfu/g on day 3 and 6.16 ± 0.74 log10 cfu/g on day 17. PMA-qPCR further validated these results, showing viable cell counts of 6.09 ± 0.68 log10 cells/g wet faeces on day 3 and 6.44 ± 0.64 log10 cells/g wet faeces on day 17. While each method detected B. longum BB536 in some participants where the other did not, no participant tested negative by both methods at any time point. This complementarity between LMT culturing and PMA-qPCR ensures a comprehensive detection strategy, confirming the presence and resilience of B. longum BB536 in the gastrointestinal tract and underscoring its potential as a beneficial probiotic strain (UMIN000052110). Japan Conference of Clinical Research: registration number: BYG2B-01; University Hospital Medical Information Network: study protocol registration UMIN000052110.

A new certified reference material IAEA-465 for radionuclides in Baltic Sea sediment

Certified reference material (CRM) for natural (40K,210Pb,210Po,226Ra,228Ra,228Th,230Th,232Th,234U,235U, and238U) and anthropogenic (137Cs,239+240Pu, and241Am) radionuclides in marine sediment from the Baltic Sea (IAEA-465) has been developed. Information values are given for 238Pu,239Pu and240Pu. Altogether 27 laboratories participated in this exercise. Radiometric (alpha-spectrometry, gamma-spectrometry and beta counting, as well as mass spectrometry (ICP-MS and AMS) techniques were applied in measurements. The CRM is intended to be used for Quality Assurance/Quality Control of radionuclide analyses, for the development and validation of analytical methods, for the development of reference methods and for training purposes.

Cytogenetic validation of DS02R1-estimated dose for atomic bomb survivors in Hiroshima and Nagasaki with FISH

INTRODUCTION

For Hiroshima and Nagasaki survivors, it has not been possible to calculate individual doses from the cytogenetic data and compare them with the physically estimated doses. This is because the cytogenetic studies used solid Giemsa staining which only provides the percent of cells bearing at least one stable-type aberration (most of the unstable-type aberrations had already disappeared), and a gamma-ray dose plus a 10-times neutron dose was used to integrate the data for both cities.

OBJECTIVES

To compare the FISH-derived gamma-ray dose with the DS02R1-derived gamma-ray dose after correcting for a contribution of the neutron dose. It was also an attempt to determine if the frequency of stable-type aberrations had remained unchanged after the exposure.

METHODS

Stable exchange-type aberration data was obtained using the 2-color FISH method from 1,868 atomic bomb survivors in Hiroshima and Nagasaki. The collected frequency was first extended to a genome-equivalent frequency. Then, by using known induction rates of exchange-type aberrations in vitro caused by neutrons and gamma-rays, respectively, and the mean relationship between the neutron and gamma-ray doses in the DS02R1 estimates for the survivors, the gamma-ray effect was estimated from the total yield of translocations.

RESULTS

It was found that over 95% of individual cytogenetic gamma-ray doses fell within the expected range of plus/minus about 1 Gy from the DS02R1 dose and the mean slope for the linear regression was 0.98, which reassures us of the validity of the DS02R1 study.

CONCLUSIONS

The present results demonstrate the validity of the individual DS02R1 doses, and that the frequency of stable-type aberrations in blood lymphocytes did not decay over the years, and thus is useful for retrospective dose evaluations of exposures which took place in the distant past.

Association analysis of production traits of Japanese quail (Coturnix japonica) using restriction-site associated DNA sequencing

This study was designed to perform an association analysis and identify SNP markers associated with production traits of Japanese quail using restriction-site-associated DNA sequencing. Weekly body weight data from 805 quail were collected from hatching to 16 weeks of age. A total number of 3990 eggs obtained from 399 female quail were used to assess egg quality traits. Egg-related traits were measured at the beginning of egg production (first stage) and at 12 weeks of age (second stage). Five eggs were analyzed at each stage. Traits, such as egg weight, egg length and short axes, eggshell strength and weight, egg equator thickness, yolk weight, diameter, and colour, albumen weight, age of first egg, total number of laid eggs, and egg production rate, were assessed. A total of 383 SNPs and 1151 associations as well as 734 SNPs and 1442 associations were identified in relation to quail production traits using general linear model (GLM) and mixed linear model (MLM) approaches, respectively. The GLM-identified SNPs were located on chromosomes 1-13, 15, 17-20, 24, 26-28, and Z, underlying phenotypic traits, except for egg and albumen weight at the first stage and yolk yellowness at the second stage. The MLM-identified SNPs were positioned on defined chromosomes associated with phenotypic traits except for the egg long axis at the second stage of egg production. Finally, 35 speculated genes were identified as candidate genes for the targeted traits based on their nearest positions. Our findings provide a deeper understanding and allow a more precise genetic improvement of production traits of Galliformes, particularly in Japanese quail.

Leveraging big data of immune checkpoint blockade response identifies novel potential targets

BACKGROUND

The development of immune checkpoint blockade (ICB) has changed the way we treat various cancers. While ICB produces durable survival benefits in a number of malignancies, a large proportion of treated patients do not derive clinical benefit. Recent clinical profiling studies have shed light on molecular features and mechanisms that modulate response to ICB. Nevertheless, none of these identified molecular features were investigated in large enough cohorts to be of clinical value.

MATERIALS AND METHODS

Literature review was carried out to identify relevant studies including clinical dataset of patients treated with ICB [anti-programmed cell death protein 1 (PD-1)/programmed death-ligand 1 (PD-L1), anti-cytotoxic T-lymphocyte antigen 4 (CTLA-4) or the combination] and available sequencing data. Tumor mutational burden (TMB) and 37 previously reported gene expression (GE) signatures were computed with respect to the original publication. Biomarker association with ICB response (IR) and survival (progression-free survival/overall survival) was investigated separately within each study and combined together for meta-analysis.

RESULTS

We carried out a comparative meta-analysis of genomic and transcriptomic biomarkers of IRs in over 3600 patients across 12 tumor types and implemented an open-source web application (predictIO.ca) for exploration. TMB and 21/37 gene signatures were predictive of IRs across tumor types. We next developed a de novo GE signature (PredictIO) from our pan-cancer analysis and demonstrated its superior predictive value over other biomarkers. To identify novel targets, we computed the T-cell dysfunction score for each gene within PredictIO and their ability to predict dual PD-1/CTLA-4 blockade in mice. Two genes, F2RL1 (encoding protease-activated receptor-2) and RBFOX2 (encoding RNA-binding motif protein 9), were concurrently associated with worse ICB clinical outcomes, T-cell dysfunction in ICB-naive patients and resistance to dual PD-1/CTLA-4 blockade in preclinical models.

CONCLUSION

Our study highlights the potential of large-scale meta-analyses in identifying novel biomarkers and potential therapeutic targets for cancer immunotherapy.

Prognosis of hypertrophic cardiomyopathy in Japanese patients with an implantable cardioverter defibrillator -focus on apical hypertrophic cardiomyopathy

Background

Patients with hypertrophic cardiomyopathy (HCM) are at high risk of lethal arrhythmias, and implantable cardioverter defibrillators (ICD) are widely used for prevention of sudden cardiac death (SCD). Apical HCM is a phenotype variant of HCM, with hypertrophy predominantly affecting apex, that was initially described 30 years ago. Apical HCM patients may have different clinical prognosis compared with other subsets of HCM. In previous studies, apical HCM patients seem to have a more benign prognosis than other types of HCM. However, little is known about the long-term outcomes of apical HCM patients and there are many unclear points. Moreover, there are few reports about the clinical prognosis in apical HCM patients with an ICD.

Objective

The aim of this study is to identify the difference between the prognosis of apical and the other types of HCM patients with an ICD.

Methods

We retrospectively analyzed the database of our ICD clinic. All subjects underwent ICD implantation between October 2006 and September 2018. We classified HCM patients into LV outflow tract obstruction (LVOTO) and midventricular obstruction (MVO), apical HCM and other non-obstructive types. We divided all the patients into apical and other types of HCM, and examined their background, incidence of appropriate ICD therapies, hospitalization for heart failure, electrical storm and death.

Results

A total of consecutive 64 Japanese HCM patients with an ICD (follow-up period, 86±24 months; age, 65±14 years; male sex, 83%; left ventricular ejection fraction, 56±14%; LV max wall-thickness, 19±7mm; LV apical aneurysm, 9.4%; 5-year risk of SCD, 4.4±2.1) were enrolled in this study. We classified them into 14 apical HCM and 50 other types of HCM patients. The clinical characteristics and major clinical events of these patients are shown in the Table 1. During the follow-up periods, there were no significant differences in the incidence of electrical storm, hospitalization for heart failure and death between the 2 groups (p=0.11; p=0.60; p=0.39). Appropriate ICD therapies occurred in 6 of 14 (43%) patients with apical HCM and 5 of 50 (10%) patients with other types of HCM (p=0.010). The risk factors of patients with apical HCM patients are shown in Table 2.

Conclusions

Appropriate ICD therapy was more prevalent in patients with apical HCM, compared to patients with other types of HCM. Aggressive intervention such as catheter ablation for ventricular tachycardia and ventricular fibrillation may be considered in patients with apical HCM and higher score of 5-year risk of SCD. Further studies are needed to clarify the manifestations and long-term outcome of apical HCM patients.

Funding Acknowledgement

Type of funding sources: None.

A genome-wide association and fine-mapping study of white rust resistance in hexaploid chrysanthemum cultivars with a wild diploid reference genome

White rust caused by Puccinia horiana is one of the most serious diseases of chrysanthemum (Chrysanthemum × morifolium). In this study, we report the DNA markers associated with resistance against P. horiana via a simple approach using the genome of a wild diploid relative, Chrysanthemum seticuspe. First, we identified the important region of the genome in the resistant cultivar "Ariesu" via a genome-wide association study. Simplex single nucleotide polymorphism (SNP) markers mined from ddRAD-Seq were used in a biparental population originating from crosses between resistant "Ariesu" and susceptible "Yellow Queen". The C. seticuspe genome was used as a reference. For the fine mapping of P. horiana resistance locus 2 (Phr2), a comparative whole genome sequencing study was conducted. Although the genome sequences of chrysanthemum cultivars assembled via the short-read approach were fragmented, reliable genome alignments were reconstructed by mapping onto the chromosome level of the C. seticuspe pseudomolecule. Base variants were then identified by comparing the assembled genome sequences of resistant "Ariesu" and susceptible "Yellow Queen". Consequently, SNP markers that were closer to Phr2 compared with ddRAD-Seq markers were obtained. These SNP markers co-segregated with resistance in F₁ progenies originating from resistant "Ariesu" and showed robust transferability for detecting Phr2-conferring resistance among chrysanthemum genetic resources. The wild C. seticuspe pseudomolecule, a de facto monoploid genome used for ddRAD-Seq analysis and assembled genome sequence comparison, demonstrated this method's utility as a model for developing DNA markers in hexaploid chrysanthemum cultivars.

OP0110 CELL-TYPE-SPECIFIC TRANSCRIPTOME ARCHITECTURE UNDERLYING THE ESTABLISHMENT AND EXACERBATION OF SYSTEMIC LUPUS ERYTHEMATOSUS

Background

Systemic lupus erythematosus (SLE) is a complex autoimmune disease with unknown etiology involving multiple immune cells and has diverse clinical phenotypes. This heterogeneous nature has hampered a better understanding of SLE pathogenesis and the development of effective therapeutic agents. While recent single-cell RNA sequencing studies of SLE identified several important cell subpopulations, they were limited by sparse expression information at single-cell level and small sample sizes.

Objectives

This study aimed to elucidate the dysregulated gene expression pattern linked to multiple clinical statuses of SLE with a fine cellular resolution and higher sensitivity. We also attempted to resolve a complex interaction between risk variants and the transcriptome dysregulation seen in SLE patients.

Methods

We conducted a large-scale bulk transcriptome study of 6,386 RNA-sequencing data including 27 purified immune cell types in peripheral blood from 136 SLE and 89 healthy donors in the Immune Cell Gene Expression Atlas from the University of Tokyo (ImmuNexUT) cohort1. At enrollment, SLE patients had diverse clinical manifestations (disease activity, organ involvement and treatment profiles) and 22 patients were re-evaluated after belimumab treatment.

Results

We first profiled two distinct cell-type-specific transcriptomic signatures: disease-state and disease-activity signatures, reflecting disease establishment and exacerbation, respectively.

After confirming the high replicability of both signatures in independent cohorts, we identified candidates of biological processes unique to each signature: e.g., upregulated E2F transcriptional activity in Th1, CD8+ memory T-lineage and NK cells, and dynamic increase of IL21 and CXCL13 in Th1 cells in an active phase of SLE. Pathway analysis highlighted the importance of immunometabolic process for SLE (e.g., oxidative phosphorylation) in cell-type-specific resolution.

Moreover, we demonstrated cell-type-specific contributions to diverse organ involvement, e.g., Th1 for mucocutaneous, monocyte-lineage cells for musculoskeletal, neutrophil-lineage cells for renal activity, respectively.

We also observed the strong associations of disease-activity signatures with treatment effect: (i) belimumab suppressed activity signatures from B-lineage cells, especially in good responders and (ii) mycophenolate mofetil substantially suppressed activity signatures from plasmablast, Th1, and central memory CD8 cells.

However, through stratified LD score regression using large-scale SLE-GWASs, we revealed that disease-activity signatures were less enriched around SLE risk variants than disease-state signatures. Consistent with this result, the directions of SLE risk alleles’ expression quantitative trait locus (eQTL) effects were significantly concordant with the directions of disease-state signatures, but not with those of activity signatures. These findings suggested that the current genetic case-control studies may not well capture clinically vital biology linked to drug target discovery for SLE. Meanwhile, we also detected some examples of activity signatures that might contribute to the disease risk by modulating risk allele’s eQTL effects.

Figure 1.

Conclusion

We identified comprehensive gene signatures reflecting the establishment and exacerbation of SLE, which provide essential foundations for future genomic, genetic, and clinical studies.

References

[1]Ota, M. et al. Dynamic landscape of immune cell-specific gene regulation in immune-mediated diseases. Cell 2021;184:3006-21.e17.

Acknowledgements

This study was supported by Chugai Pharmaceutical Co., Ltd., Tokyo, Japan; the Ministry of Education, Culture, Sports; and the Japan Agency for Medical Research and Development (AMED) (JP21tm0424221 and JP21zf0127004).

Disclosure of Interests

Masahiro Nakano: None declared, Mineto Ota Grant/research support from: Mineto Ota belongs to the Social Cooperation Program, Department of functional genomics and immunological diseases, supported by Chugai Pharmaceutical., Yusuke Takeshima Grant/research support from: Yusuke Takeshima belonged to the Social Cooperation Program, Department of functional genomics and immunological diseases, supported by Chugai Pharmaceutical., Yukiko Iwasaki: None declared, Hiroaki Hatano: None declared, Yasuo Nagafuchi Grant/research support from: Yasuo Nagafuchi belongs to the Social Cooperation Program, Department of functional genomics and immunological diseases, supported by Chugai Pharmaceutical., Kwangwoo Kim: None declared, So-Young Bang: None declared, Hye Soon Lee: None declared, Hirofumi Shoda: None declared, Xuejun Zhang: None declared, Sang-Cheol Bae: None declared, Chikashi Terao: None declared, Kazuhiko Yamamoto: None declared, Tomohisa Okamura Grant/research support from: Tomohisa Okamura belongs to the Social Cooperation Program, Department of functional genomics and immunological diseases, supported by Chugai Pharmaceutical., Kazuyoshi Ishigaki: None declared, Keishi Fujio Speakers bureau: Keishi Fujio receives speaker fees from Chugai Pharmaceutical., Consultant of: Keishi Fujio receives consulting honoraria from Chugai Pharmaceutical., Grant/research support from: Keishi Fujio receives research support from Chugai Pharmaceutical.

Association between right ventricular dysfunction and appropriate icd therapy

Funding Acknowledgements

Type of funding sources: None.

Background

Right ventricular fractional area change (RVFAC) as right ventricular function is recently referred as an independent predictor of sudden cardiac death (SCD). The purpose of this study was to evaluate the association of RVFAC and appropriate ICD therapy in order to determine the cut-off value of RVFAC.

Methods

Consecutive patients who underwent initial ICD implantation for any diseases except for non-dilated phase hypertrophic cardiomyopathy and channelopathy were retrospectively enrolled from 2012 to 2018. Primary endpoint was an initial appropriate ICD therapy. Transthoracic echocardiographic parameters before ICD implantation were evaluated by one physician and one echocardiologist to be validated. Right ventricular dimensions and function were also measured to be analyzed.

Results

In total, 172 patients (60.3±13.6 years, 131 males) including 63 ischemic cardiomyopathy were enrolled. Ninety patients received an ICD as a secondary prophylaxis. Mean LVEF and RVFAC were 38.3±14.3% and 35.8±8.82%, respectively. There was little correlation between RVFAC and LVEF (correlation coefficient =0.274). Regarding appropriate ICD therapy events, the best cut-off value of RVFAC was 34.8%. The odds ratio of low RVFAC was 2.731 (95%CI: 1.456-5.121, P=0.00174). Secondary prophylactic cohort with low RVFAC showed highest incidence of appropriate ICD therapy as shown in the figure. In multivariate analysis, only low RVFAC is an independent predictor of appropriate ICD therapy (HR: 3.53, 95%CI:1.78- 6.99, P=0.0003).

Conclusion

Low RVFAC seemed independently associated with increased appropriate ICD therapy.

The complete sequence of the chloroplast genome of Chrysanthemum rupestre, a diploid disciform capitula species of Chrysanthemum

In this study, we analyzed the complete sequence of the chloroplast genome of Chrysanthemum rupestre Matsum. et Koidz., 1910, a diploid disciform capitula species of Chrysanthemum endemic to Japan, formerly classified as Ajania rupestris (Matsum. & Koidz.) Muldashev, Bot. Zhurn. (Moscow & Leningrad), 1983. The chloroplast genome of C. rupestre has a typical conserved quadripartite structure of 151,061 bp in length, comprising a large single-copy region (82,846 bp), a small single-copy region (18,301 bp), and a pair of inverted repeat regions (each 24,957 bp). Phylogenetic analysis indicated that C. rupestre clustered with other Chrysanthemum species, including another former Ajania species, Chrysanthemum pacificum Nakai, 1928. However, Ajania variifolia (C.C.Chang) Tzvelev, 1961, which is a synonym of Phaeostigma variifolium (C.C.Chang) Muldashev, 1981, was placed outside the Chrysanthemum clade, thereby implying that the former genus Ajania includes heterogeneous species.

A phase II trial of stereotactic body radiotherapy in 4 fractions for patients with localized prostate cancer

Purpose/objective(s)

To report results from our phase II study of stereotactic body radiotherapy (SBRT) delivering 36 Gy in 4 fractions for patients with localized prostate cancer.

Materials/methods

We enrolled 55 patients treated with SBRT delivering 36 Gy in 4 fractions between 2015 to 2018. All patients were categorized as low-risk (n = 4), intermediate-risk (n = 31) or high-risk (n = 20) according to National Comprehensive Cancer Network criteria. Median age was 73 years (range 54–86 years). Two-thirds of patients (n = 37) had received androgen-deprivation therapy for 3–46 months (median, 31 months). Median duration of follow-up was 36 months (range 1–54 months). We used Radiation Therapy Oncology Group and National Cancer Institute—Common Toxicity Criteria version 4 for toxicity assessments. Quality of life (QOL) outcomes were also evaluated using the Expanded Prostate Cancer Index Composite (EPIC).

Results

Protocol treatments were completed for all patients. Six patients experienced biochemical failures. Among these six patients, three patients experienced clinical failure. One patient showed bone metastasis before biochemical failure. One patient died of gastric cancer. The 3-year biochemical control rate was 89.8%. Acute grade 2 genitourinary (GU) and gastrointestinal (GI) toxicities were observed in 5 patients (9%) and 6 patients (11%), respectively. No grade 3 or higher acute toxicities were observed. Late grade 2 GU and GI toxicities were observed in 7 patients (13%) and 4 patients (7%), respectively. Late grade 3 GU and GI toxicities were observed in 1 patient (1.8%) each. EPIC scores decreased slightly during the acute phase and recovered within 3 months after treatment.

Conclusion

Our phase II study showed that SBRT delivering 36 Gy in 4 fractions was safe and effective with favorable QOL outcomes, although this regimen showed slightly more severe toxicities compared to current standards.

Learning curve of visually-guided laser balloon ablation of paroxysmal atrial fibrillation

Funding Acknowledgements

Type of funding sources: None.

Background

The visually-guided laser balloon (VGLB) is a compliant, variable-diameter balloon that delivers laser energy around the pulmonary vein (PV) ostium under real-time endoscopic visualization. However, limited data exist in Japan thus far. Therefore, we determined the safety, efficacy, and learning curve of the VGLB for PV isolation.

Methods

A total of 52 consecutive patients with paroxysmal atrial fibrillation were prospectively enrolled and divided into 3 groups (T1 = 15 patients, T2 = 15 patients, T3 = 22 patients). All patients underwent PV isolation by 2 operators using the VGLB. The operators were experienced in radiofrequency and cryothermal procedures, but not in laser ablations.

Results

Tables show the acute clinical results. Reversible phrenic nerve palsy occurred in 3.8%, with a trend towards a lower complication rate with increasing experience.

Conclusions

The VGLB was safe and effective for PV isolation, even for operators without any previous experience. Procedure time decreased after a learning curve of 30 cases. Abstract Figure. Procedural data and isolation rates

Prognosis of apical hypertrophic cardiomyopathy in patients with an implantable cardioverter defibrillator

Background

Prophylactic use of implantable cardioverter-defibrillators (ICDs) to prevent sudden cardiac death (SCD) is widely spread all over the world in patients with hypertrophic cardiomyopathy (HCM). Apical HCM is a phenotype variant of HCM, with hypertrophy predominantly affecting apex, that was initially described 30 years ago. Apical HCM patients may have different clinical prognosis compared with other subsets of HCM. In previous studies, apical HCM patients seem to have a more benign prognosis than other types of HCM. However, little is known about the long-term outcomes of apical HCM and there are many unclear points. Moreover, there are few reports about the clinical prognosis in apical HCM patients with an ICD.

Objective

The aim of this study is to identify the difference between the prognosis of apical and the other HCM patients with an ICD.

Methods

We retrospectively analyzed the database of our ICD clinic. All subjects had been implanted with an ICD from October 2006 to August 2017. We classified HCM patients into LV outflow tract obstruction (LVOTO) and midventricular obstruction (MVO), apical HCM and other non-obstructive types. We divided all the patients into apical and other types of HCM, and examined their background, incidence of appropriate ICD therapies, hospitalization for heart failure, electrical storm and death.

Results

A total of consecutive 62 Japanese HCM patients with an ICD (follow-up period, 86±25 months; age, 67±14 years; male sex, 85%; left ventricular ejection fraction, 57±12%; LV max wall-thickness, 19±5mm; LV apical aneurysm, 9.7%; HCM Risk-SCD, 4.4±3.0) were enrolled in this study. We classified them into 14 apical HCM and 48 other types of HCM patients. The clinical characteristics and major events of these patients are shown in the Figure. During the follow-up periods, there were no significant differences in the incidence of hospitalization for heart failure, electrical storm and death between the 2 groups (p=0.40; p=0.22; p=0.23). Appropriate therapies occurred in 5 of 14 (36%) patients with apical HCM and 4 of 48 (8.3%) patients with other types of HCM (p=0.022).

Conclusions

Appropriate ICD therapy was more prevalent in patients with apical HCM, compared to patients with other types of HCM. However, the incidences of hospitalization for heart failure, electrical storm and death were not significantly different between two groups.

Funding Acknowledgement

Type of funding sources: None.

Predictive value of QRS duration normalized to left ventricular volume for responding to cardiac resynchronization therapy in patients with mid-QRS duration enrolled in the multicenter registry

Background

For cardiac resynchronization therapy (CRT), patients with chronic heart failure (HF) and wide (>150msec) QRS duration (QRSd) received class I/A indication. However, its beneficial effect seemed to be limited for those with mid- (120–150msec) QRSd. Recent studies demonstrated that QRSd normalized to left ventricular end-diastolic volume (QRSd/ LVEDV) improved prediction of clinical outcome in patients with CRT. Therefore, we sought to investigate predictive value of QRSd/LVEDV for responding to CRT in patients with mid-QRSd.

Methods

This was retrospective multi-center observational cohort study. A total 506 consecutive patients who underwent CRT implantation in Tohoku University Hospital and National Cerebral and Cardiovascular Center were evaluated. Exclusion criteria were QRSd less than 120ms, upgrade procedures from other implanted non-CRT devices and bradycardia requiring pacing. We evaluated clinical variables, data of electrocardiogram and transthoracic echocardiography at baseline and 6 months after CRT implantation. Primary endpoint was a HF hospitalization after CRT implantation. Distribution of free from HF hospitalization during follow-up was calculated using Kaplan-Meier curves, and the effects of covariate on the time to endpoint were investigated using a Cox proportional hazards model.

Results

After 199 patients were excluded based on exclusion criterion, remaining 307 patients were included for the analysis. Mean age was 62±14 [SD] years, and 238 (77%) were male. Mean LVEF and LVEDV were 25±9% and 234±82ml, respectively, and 24% of patients had ischemic etiology of HF. During the median 948 days of follow-up, CRT patients with mid QRSd (n=126; 136±10msec), as compared with those with wide QRSd (n=181; 174±17msec), tended to have higher incidence of HF hospitalization (Wilcoxon p=0.03). Multivariate analysis showed that QRSd and QRSd/LVEDV were significant predictors for HF hospitalization in CRT patients with mid QRSd, and cut-off values (137msec of QRSd and 0.65 of QRSd/LVEDV), which was calculated by receiver operative curve analysis, was used for risk stratification. QRSd<137msec was significant negative predictors for HF hospitalization (p=0.005), and Mid-QRSd patients with QRSd≥137msec demonstrated equivalent clinical outcome with those with wide QRSd. Moreover, patients with QRSd/LVEDV≥0.65 tended to have lower incidence of HF hospitalization as compared with those without it among patients with QRSd<137msec (n=64, Figure).

Conclusion

The present study demonstrates that QRSd normalized to left ventricular end-diastolic volume (QRSd/ LVEDV) could be clinical value in predicting outcome in CRT patients with mid-QRSd. These findings indicate normalized QRSd reflects myocardial conduction properties and contribute to risk stratification.

Funding Acknowledgement

Type of funding sources: None.

Risk stratification for ischemic stroke and major bleeding in patients without atrial fibrillation – application of CHA2DS2-VASc and HAS-BLED scores

Background

Atrial fibrillation (AF) is the most common arrhythmia. AF-related stroke tends to be more severe, and the mortality rate is higher compared with stroke without AF. Recent cardiac implantable electronic devices (CIEDs) have led to an improvement in the early detection of AF episodes. Previous studies showed that AF episodes detected by CIEDs are associated with ischemic stroke. However, little is known about the relationship between new-onset AF and ischemic stroke events in Japanese patients with CIEDs who have no prior AF and take no anticoagulant therapy. ESC guidelines for the management of AF recommend the use of CHA2DS2-VASc score as class I to predict the risk of ischemic stroke in patients with AF. However, the validity of the CHA2DS2-VASc and HAS-BLED scores to predict ischemic stroke and major bleeding events in patients without AF remains unclear.

Objective

The purpose of this study was to identify the incidence of ischemic stroke and major bleeding events in CIEDs patients without AF and assess the validity of CHA2DS2-VASc and HAS-BLED scores in this population.

Methods

We retrospectively analyzed the database of our CIEDs clinic. Every 6 months, CIEDs were checked using remote monitoring system. We examined the characteristics and incidence of ischemic stroke and bleeding events. In addition, we investigated the relationship between CHA2DS2-VASc and HAS-BLED scores and the incidence of these events.

Results

We enrolled 620 consecutive patients who were followed up at our CIED clinic. We excluded patients who had a history of AF or had received anticoagulant therapies, 348 patients (follow-up period, 65±58 months; age, 70±16 years; male sex; 64%; defibrillator, 55%) were included in this study. The mean CHA2DS2-VASc and HAS-BLED scores were 2.8±1.5 points and 1.7±1.6 points, respectively. During the follow-up, 23 (6.6%) and 12 (3.4%) of 348 patients had ischemic stroke and major bleeding events, respectively. The incidence of ischemic stroke and major bleeding events stratified by the CHA2DS2-VASc and HAS-BLED scores were shown in Figure 1.

Conclusion

The risk stratification for ischemic stroke and major bleeding using the CHA2DS2-VASc and HAS-BLED scores is valid in patients without AF.

Funding Acknowledgement

Type of funding sources: None. Figure 1

Psychological assessment of depression and anxiety in patients with implantable cardioverter-defibrillator: DEFibrillator-related distress and depression survey in Chiba 2

Background

Despite the established treatment for life-threatening arrhythmias, the implantable cardioverter-defibrillator (ICD) therapy has emerged as a major determinant of psychological distress. Previous studies have showed several approaches to assess the ICD-specific psychological distress, however, the risk factors affecting psychological functioning are relatively variable across studies, and are not well studied in Japanese population. Therefore, we prospectively investigate the risk factors affecting the psychological functioning and assess the impact of ICD therapy in Japanese patients with ICD.

Methods

We prospectively enrolled consecutive 136 patients in the present study. At the time of ICD implantation and 1 year later, all patients completed the Florida Shock Anxiety Scale (FSAS), which is a tool designed to provide a quantitative measure of ICD shock-related anxiety. In addition, patients were also examined by psychiatrists using two assessment scales, Montgomery-Åsberg Depression Rating Scale (MADRS) and Hospital Anxiety and Depression Scale (HADS).

Results

The FSAS score was significantly correlated with the MADRS and HADS scores (Figure). During 1-year follow-up, 11 patients (8.1%) received ICD therapy. Younger age was significantly associated with the FSAS and MADRS scores at registration, but ICD therapy was the only independent factor associated with the increased risk of the FSAS score at 1 year later (p-value = 0.012).

Conclusions

ICD therapy has a strong impact on psychological distress in time course of ICD implantation. To reduce unnecessary shock therapy and optimal intervention by healthcare professionals may lead to the improvement of ICD-related psychological functioning.

Funding Acknowledgement

Type of funding sources: None. Figure 1. Correlation between MADRS and HADS scoreFigure 2. FSAS, MADRS and HADS scores

A chromosome-level genome sequence of Chrysanthemum seticuspe, a model species for hexaploid cultivated chrysanthemum

Chrysanthemums are one of the most industrially important cut flowers worldwide. However, their segmental allopolyploidy and self-incompatibility have prevented the application of genetic analysis and modern breeding strategies. We thus developed a model strain, Gojo-0 (Chrysanthemum seticuspe), which is a diploid and self-compatible pure line. Here, we present the 3.05 Gb chromosome-level reference genome sequence, which covered 97% of the C. seticuspe genome. The genome contained more than 80% interspersed repeats, of which retrotransposons accounted for 72%. We identified recent segmental duplication and retrotransposon expansion in C. seticuspe, contributing to arelatively large genome size. Furthermore, we identified a retrotransposon family, SbdRT, which was enriched in gene-dense genome regions and had experienced a very recent transposition burst. We also demonstrated that the chromosome-level genome sequence facilitates positional cloning in C. seticuspe. The genome sequence obtained here can greatly contribute as a reference for chrysanthemum in front-line breeding including genome editing.

Intragenic complementation at the Lotus japonicus CELLULOSE SYNTHASE-LIKE D1 locus rescues root hair defects

Root hair cells form the primary interface of plants with the soil environment, playing key roles in nutrient uptake and plant defense. In legumes, they are typically the first cells to become infected by nitrogen-fixing soil bacteria during root nodule symbiosis. Here, we report a role for the CELLULOSE SYNTHASE-LIKE D1 (CSLD1) gene in root hair development in the legume species Lotus japonicus. CSLD1 belongs to the cellulose synthase protein family that includes cellulose synthases and cellulose synthase-like proteins, the latter thought to be involved in the biosynthesis of hemicellulose. We describe 11 Ljcsld1 mutant alleles that impose either short (Ljcsld1-1) or variable (Ljcsld1-2 to 11) root hair length phenotypes. Examination of Ljcsld1-1 and one variable-length root hair mutant, Ljcsld1-6, revealed increased root hair cell wall thickness, which in Ljcsld1-1 was significantly more pronounced and also associated with a strong defect in root nodule symbiosis. Lotus japonicus plants heterozygous for Ljcsld1-1 exhibited intermediate root hair lengths, suggesting incomplete dominance. Intragenic complementation was observed between alleles with mutations in different CSLD1 domains, suggesting CSLD1 function is modular and that the protein may operate as a homodimer or multimer during root hair development.