Optimal left ventricular diameter measurement in subjects with sigmoid septum: comparison with three-dimensional left ventricular volume

BACKGROUND

The purpose of this study was to determine the most appropriate measurement of left ventricular (LV) end-diastolic diameter for subjects with the sigmoid septum (SS) by measuring the LV end-diastolic diameter at the base and mid-ventricle and by examining the relationship between these measurements and the three-dimensional (3D) echocardiographic LV end-diastolic volume.

METHODS

In 91 patients who underwent echocardiography for screening cardiovascular abnormalities, the aorto-septal angle (ASA) was measured as an index of the sigmoid septum. LV end-diastolic diameter was measured at the base and mid-ventricular level (DDbase and DDmid, respectively), and their average value was calculated (DDavg). By using 3D echocardiography, LV end-diastolic volume (EDV3D) was measured.

RESULTS

Among 91 patients, 48 patients had narrow ASA (< 120 degrees) and were divided into the sigmoid septum (SS) group, and the remaining 43 patients were divided into the non-SS group. In the SS group, all DDbase, DDmid, and DDavg were significantly correlated with EDV3D (r = 0.59, 0.80, and 0.76, respectively), and the correlation coefficient between DDbase and EDV3D was significantly lower than that between DDmid and EDV3D (p < 0.01). On the other hand, in the non-SS group, all DDbase, DDmid, and DDavg were significantly correlated with EDV3D (r = 0.77, 0.85, and 0.84, respectively), and the correlation coefficient between DDbase and EDV3D was statistically comparable to that between DDmid and EDV3D (p = 0.12). ASA was significantly correlated with the difference of DDmid minus DDbase (r =  - 0.71, p < 0.001).

CONCLUSIONS

In patients with SS, DDmid and DDavg were well reflected the 3D echocardiographic LV end-diastolic volume.

Transcriptional heterogeneity of catabolic genes on the plasmid pCAR1 causes host-specific carbazole degradation

To elucidate why plasmid-borne catabolic ability differs among host bacteria, we assessed the expression dynamics of the Pant promoter on the carbazole-degradative conjugative plasmid pCAR1 in Pseudomonas putida KT2440(pCAR1) (hereafter, KTPC) and Pseudomonas resinovorans CA10. The Pant promoter regulates the transcription of both the car and ant operons, which are responsible for converting carbazole into anthranilate and anthranilate into catechol, respectively. In the presence of anthranilate, transcription of the Pant promoter is induced by the AraC/XylS family regulator AntR, encoded on pCAR1. A reporter cassette containing the Pant promoter followed by gfp was inserted into the chromosomes of KTPC and CA10. After adding anthranilate, GFP expression in the population of CA10 showed an unimodal distribution, whereas a small population with low GFP fluorescence intensity appeared for KTPC. CA10 has a gene, antRCA, that encodes an iso-functional homolog of AntR on its chromosome. When antRCA was disrupted, a small population with low GFP fluorescence intensity appeared. In contrast, overexpression of pCAR1-encoded AntR in KTPC resulted in unimodal expression under the Pant promoter. These results suggest that the expression of pCAR1-encoded AntR is insufficient to ameliorate the stochastic expression of the Pant promoter. Raman spectra of single cells collected using deuterium-labeled carbazole showed that the C-D Raman signal exhibited greater variability for KTPC than CA10. These results indicate that heterogeneity at the transcriptional level of the Pant promoter due to insufficient AntR availability causes fluctuations in the pCAR1-borne carbazole-degrading capacity of host bacterial cells.IMPORTANCEHorizontally acquired genes increase the competitiveness of host bacteria under selective conditions, although unregulated expression of foreign genes may impose fitness costs. The "appropriate" host for a plasmid is empirically known to maximize the expression of plasmid-borne traits. In the case of pCAR1-harboring Pseudomonas strains, P. resinovorans CA10 exhibits strong carbazole-degrading capacity, whereas P. putida KT2440 harboring pCAR1 exhibits low degradation capacity. Our results suggest that a chromosomally encoded transcription factor affects transcriptional and metabolic fluctuations in host cells, resulting in different carbazole-degrading capacities as a population. This study may provide a clue for determining appropriate hosts for a plasmid and for regulating the expression of plasmid-borne traits, such as the degradation of xenobiotics and antibiotic resistance.

A reference genome of Commelinales provides insights into the commelinids evolution and global spread of water hyacinth (Pontederia crassipes)

Commelinales belongs to the commelinids clade, which also comprises Poales that includes the most important monocot species, such as rice, wheat, and maize. No reference genome of Commelinales is currently available. Water hyacinth (Pontederia crassipes or Eichhornia crassipes), a member of Commelinales, is one of the devastating aquatic weeds, although it is also grown as an ornamental and medical plant. Here, we present a chromosome-scale reference genome of the tetraploid water hyacinth with a total length of 1.22 Gb (over 95% of the estimated size) across 8 pseudochromosome pairs. With the representative genomes, we reconstructed a phylogeny of the commelinids, which supported Zingiberales and Commelinales being sister lineages of Arecales and shed lights on the controversial relationship of the orders. We also reconstructed ancestral karyotypes of the commelinids clade and confirmed the ancient commelinids genome having 8 chromosomes but not 5 as previously reported. Gene family analysis revealed contraction of disease-resistance genes during polyploidization of water hyacinth, likely a result of fitness requirement for its role as a weed. Genetic diversity analysis using 9 water hyacinth lines from 3 continents (South America, Asia, and Europe) revealed very closely related nuclear genomes and almost identical chloroplast genomes of the materials, as well as provided clues about the global dispersal of water hyacinth. The genomic resources of P. crassipes reported here contribute a crucial missing link of the commelinids species and offer novel insights into their phylogeny.

Mitochondrial-targeting effector RsIA_CtaG/Cox11 in Rhizoctonia solani AG-1 IA has two functions: plant immunity suppression and cell death induction mediated by a rice cytochrome c oxidase subunit

Rhizoctonia solani AG-1 IA causes a necrotrophic rice disease and is a serious threat to rice production. To date, only a few effectors have been characterized in AG-1 IA. We previously identified RsIA_CtaG/Cox11 and showed that infiltration of the recombinant protein into rice leaves caused disease-like symptoms. In the present study, we further characterized the functionality of RsIA_CtaG/Cox11. RsIA_CtaG/Cox11 is an alternative transcript of cytochrome c oxidase copper chaperone Cox11 that starts from the second AUG codon, but contains a functional secretion signal peptide. RNA interference with RsIA_CtaG/Cox11 reduced the pathogenicity of AG-1 IA towards rice and Nicotiana benthamiana without affecting its fitness or mycelial morphology. Transient expression of the RsIA_CtaG/Cox11-GFP fusion protein demonstrated the localization of RsIA_CtaG/Cox11 to mitochondria. Agro-infiltration of RsIA_CtaG/Cox11 into N. benthamiana leaves inhibited cell death by BAX and INF1. In contrast to rice, agro-infiltration of RsIA_CtaG/Cox11 did not induce cell death in N. benthamiana. However, cell death was observed when it was coinfiltrated with Os_CoxVIIa, which encodes a subunit of cytochrome c oxidase. Os_CoxVIIa appeared to interact with RsIA_CtaG/Cox11. The cell death triggered by coexpression of RsIA_CtaG/Cox11 and Os_CoxVIIa is independent of the leucine-rich repeat receptor kinases BAK1/SOBIR1 and enhanced the susceptibility of N. benthamiana to AG-1 IA. Two of the three evolutionarily conserved cysteine residues at positions 25 and 126 of RsIA_CtaG/Cox11 were essential for its immunosuppressive activity, but not for cell death induction. This report suggests that RsIA_CtaG/Cox11 appears to have a dual role in immunosuppression and cell death induction during pathogenesis.

Characterization of diterpene synthase genes in Brachypodium distachyon, a monocotyledonous model plant, provides evolutionary insight into their multiple homologs in cereals

Gibberellins are diterpenoid phytohormones that regulate plant growth, and are biosynthesized from a diterpene intermediate, ent-kaurene, which is produced from geranylgeranyl diphosphate via ent-copalyl diphosphate (ent-CDP). The successive 2 cyclization reactions are catalyzed by 2 distinct diterpene synthases, ent-CDP synthase (ent-CPS) and ent-kaurene synthase (KS). Various diterpene synthase genes involved in specialized metabolism were likely created through duplication and neofunctionalization of gibberellin-biosynthetic ent-CPS and KS genes in crops. Brachypodium distachyon is a monocotyledonous species that is a model plant in grasses. We herein found 1 ent-CPS gene homolog BdCPS and 4 tandemly arrayed KS-like genes BdKS1, KSL2, KSL3, and KSL4 in the B. distachyon genome, a simpler collection of paralogs than in crops. Phylogenetic and biochemical analyses showed that BdCPS and BdKS1 are responsible for gibberellin biosynthesis. BdKSL2 and BdKSL3 are suggested to be involved in specialized diterpenoid metabolism. Moreover, we restored KS activity of BdKSL2 through amino acid substitution.

Chemical screening of inhibitors specific for MdDOX-Co that cause an apple columnar tree-shape

MdDOX-Co, the ectopic expression of which is considered to cause the apple columnar tree shape, belongs to the 2-oxoglutarate-dependent dioxygenase (2ODD) family. It adds a hydroxyl group to position 12 of gibberellins (GAs). However, the 2ODD enzymes related to GA biosynthesis and catabolism are phylogenetically distinct from MdDOX-Co. Thus, it is possible that substrates other than GAs exist in MdDOX-Co. To identify the previously unidentified substrate(s) of MdDOX-Co, we searched for MdDOX-Co-specific inhibitors. Chemical screening using gas chromatography-mass spectrometry was performed to investigate the effects of 2400 compounds that inhibited the catalytic reaction of MdDOX-Co, but not the catabolic reaction of GA 2-oxidase, an enzyme involved in GA catabolism. By applying two positive compounds in Arabidopsis, a chemical 3-((2-chloro-6-fluorobenzyl)thio)-5,7-dimethyl-5H-pyrazolo[3,4-e][1,4,2]dithiazine-1,1-dioxide designated as TPDD that did not inhibit GA biosynthesis was selected. The structure-activity relationships among the TPDD analogs were also obtained.

Difference in the ligand affinity among redundant plant hormone receptors of rice OsCOI1a/1b/2-OsJAZs

(3R, 7S)-jasmonoyl-L-isoleucine (JA-Ile) is a lipid-derived plant hormone that regulates plant responses, including biotic/abiotic stress adaptation. In the plant cells, JA-Ile is perceived by COI1-JAZ co-receptor by causing protein-protein interaction between COI1 and JAZ proteins to trigger gene expressions. In this study, we focused on Oryza sativa, a model monocot and an important crop, with 45 possible OsCOI-OsJAZ co-receptor pairs composed of three OsCOI homologs (OsCOI1a, OsCOI1b, and OsCOI2) and 15 OsJAZ homologs. We performed fluorescein anisotropy and pull-down assays to examine the affinity between JA-Ile and OsCOI1a/1b/2-OsJAZ1-15 co-receptor pairs. The results revealed a remarkable difference in the modes of ligand perception by OsCOI1a/1b and OsCOI2. Recently, the unique function of OsCOI2 in some of the JA-responses were revealed. Our current results will lead to the possible development of OsCOI2-selective synthetic ligand.

BSR1, a Rice Receptor-like Cytoplasmic Kinase, Positively Regulates Defense Responses to Herbivory

Crops experience herbivory by arthropods and microbial infections. In the interaction between plants and chewing herbivores, lepidopteran larval oral secretions (OS) and plant-derived damage-associated molecular patterns (DAMPs) trigger plant defense responses. However, the mechanisms underlying anti-herbivore defense, especially in monocots, have not been elucidated. The receptor-like cytoplasmic kinase Broad-Spectrum Resistance 1 (BSR1) of Oryza sativa L. (rice) mediates cytoplasmic defense signaling in response to microbial pathogens and enhances disease resistance when overexpressed. Here, we investigated whether BSR1 contributes to anti-herbivore defense responses. BSR1 knockout suppressed rice responses triggered by OS from the chewing herbivore Mythimna loreyi Duponchel (Lepidoptera: Noctuidae) and peptidic DAMPs OsPeps, including the activation of genes required for biosynthesis of diterpenoid phytoalexins (DPs). BSR1-overexpressing rice plants exhibited hyperactivation of DP accumulation and ethylene signaling after treatment with simulated herbivory and acquired enhanced resistance to larval feeding. As the biological significance of herbivory-induced accumulation of rice DPs remains unexplained, their physiological activities in M. loreyi were analyzed. The addition of momilactone B, a rice DP, to the artificial diet suppressed the growth of M. loreyi larvae. Altogether, this study revealed that BSR1 and herbivory-induced rice DPs are involved in the defense against chewing insects, in addition to pathogens.

Genome Editing Reveals Both the Crucial Role of OsCOI2 in Jasmonate Signaling and the Functional Diversity of COI1 Homologs in Rice

Jasmonic acid (JA) regulates plant growth, development and stress responses. Coronatine insensitive 1 (COI1) and jasmonate zinc-finger inflorescence meristem-domain (JAZ) proteins form a receptor complex for jasmonoyl-l-isoleucine, a biologically active form of JA. Three COIs (OsCOI1a, OsCOI1b and OsCOI2) are encoded in the rice genome. In the present study, we generated mutants for each rice COI gene using genome editing to reveal the physiological functions of the three rice COIs. The oscoi2 mutants, but not the oscoi1a and oscoi1b mutants, exhibited severely low fertility, indicating the crucial role of OsCOI2 in rice fertility. Transcriptomic analysis revealed that the transcriptional changes after methyl jasmonate (MeJA) treatment were moderate in the leaves of oscoi2 mutants compared to those in the wild type or oscoi1a and oscoi1b mutants. MeJA-induced chlorophyll degradation and accumulation of antimicrobial secondary metabolites were suppressed in oscoi2 mutants. These results indicate that OsCOI2 plays a central role in JA response in rice leaves. In contrast, the assessment of growth inhibition upon exogenous application of JA to seedlings of each mutant revealed that rice COIs are redundantly involved in shoot growth, whereas OsCOI2 plays a primary role in root growth. In addition, a co-immunoprecipitation assay showed that OsJAZ2 and OsJAZ5 containing divergent Jas motifs physically interacted only with OsCOI2, whereas OsJAZ4 with a canonical Jas motif interacts with all three rice COIs. The present study demonstrated the functional diversity of rice COIs, thereby providing clues to the mechanisms regulating the various physiological functions of JA.

Do Tapping and Massaging during Tourniquet Application Promote Dilation of Forearm Cutaneous Veins? A Pilot Quasi-Experimental Study

Successful insertion of a peripheral intravenous catheterization requires that veins be sufficiently dilated. This study aimed to clarify the venous dilation effect of including tapping or massaging to the application of a tourniquet at the cutaneous veins of healthy adults' forearms. This was a quasi-experimental study of 30 healthy adult volunteers. Each participant underwent all three venous dilation procedures, which included the tourniquet application (Control condition), the tourniquet application and tapping the participant's forearm (Tapping condition), as well as the tourniquet application combined with massaging the participant's forearm (Massage condition). To clarify the venous dilation effects, venous indices were measured, namely the venous diameter (mm), depth (mm), and palpation score. After applying all venous dilation procedures, the venous diameter and palpation score significantly increased. However, no significant difference was observed between the control condition and each intervention condition. The depth in the control and tapping conditions decreased significantly in contrast to the Massage condition. Moreover, a subgroup (nine participants with a venous diameter less than 3 mm after the control condition) had similar results. This study found that additional tapping or massaging after tourniquet application could be less effective in promoting dilation in the forearm veins of healthy adults. Future studies should examine the efficacy and effectiveness of venous dilation in a wide target population while considering intervention methods.

Usefulness of the pulmonary venous flow waveform for assessing left atrial stiffness

PURPOSE

This study investigated the novel non-invasive left atrial (LA) stiffness parameter using pulmonary venous (PV) flow measurements and the clinical usefulness of the novel LA stiffness parameter.

METHODS

We retrospectively analyzed 237 patients who underwent right heart catheterization and echocardiography less than one week apart. From the pulmonary artery wedge pressure waveform, the difference between x-descent and v-wave (ΔP) was measured. Using the echocardiographic biplane method of disks, the difference between LA maximum volume and that just before atrial contraction (ΔV_MOD) was calculated, and the ΔP/ΔV_MOD was calculated as a standard LA stiffness index. From the PV flow waveform, the peak systolic velocity (S), peak diastolic velocity (D), and minimum velocity between them (R) were measured, and S/D, S/R, and D/R were calculated. From the speckle tracking echocardiography-derived time-LA volume curve, the difference between LA maximum volume and that just before atrial contraction (ΔV_STE) was measured. Each patient's prognosis was investigated until three years after echocardiography.

RESULTS

Among the PV flow parameters, D/R was significantly correlated with ΔP (r = 0.62), and the correlation coefficient exceeded that between S/D and ΔP (r =  - 0.39) or S/R and ΔP (r = 0.14). The [D/R]/ΔV_STE was significantly correlated with ΔP/ΔV_MOD (r = 0.61). During the follow-up, 37 (17%) composite endpoints occurred. Kaplan-Meier analysis showed that patients with [D/R]/ΔV_STE greater than 0.13 /mL were at higher risk of cardiac events.

CONCLUSION

The [D/R]/ΔV_STE was useful for assessing LA stiffness non-invasively and might be valuable in the prognostic evaluation of patients with cardiac diseases.

Iron Induces Resistance Against the Rice Blast Fungus Magnaporthe oryzae Through Potentiation of Immune Responses

Iron is an essential nutrient required for plant growth and development. The availability of iron might also influence disease resistance in plants. However, the molecular mechanisms involved in the plant response to iron availability and immunity have been investigated separately from each other. In this work, we found that exposure of rice plants to high iron enhances resistance to infection by the fungal pathogen Magnaporthe oryzae, the causal agent of blast disease. RNA-Seq analysis revealed that blast resistance in iron-treated rice plants was associated with superinduction of defense-related genes during pathogen infection, including Pathogenesis-Related genes. The expression level of genes involved in the biosynthesis of phytoalexins, both diterpene phytoalexins and the flavonoid phytoalexin sakuranetin, was also higher in iron-treated plants compared with control plants, which correlated well with increased levels of phytoalexins in these plants during M. oryzae infection. Upon pathogen infection, lipid peroxidation was also higher in iron-treated plants compared with non-treated plants. We also show that M. oryzae infection modulates the expression of genes that play a pivotal role in the maintenance of iron homeostasis. Histochemical analysis of M. oryzae-infected leaves revealed colocalization of iron and reactive oxygen species in cells located in the vicinity of fungal penetration sites (e.g. appressoria) in rice plants that have been exposed to iron. Together these findings support that ferroptosis plays a role in the response of iron-treated rice plants to infection by virulent M. oryzae. Understanding interconnected regulations between iron signaling and immune signaling in rice holds great potential for developing novel strategies to improve blast resistance in rice.

Clinical trajectory and outcomes of patients with heart failure with preserved ejection fraction with normal or indeterminate diastolic function

Background

Heart failure (HF) with preserved ejection fraction (HFpEF) is a chronic and progressive disease, but limited therapeutic strategies are currently available. Although left ventricular diastolic dysfunction (DD) is a prominent mechanism of HFpEF, a certain number of patients with HFpEF have a normal diastolic function (ND) or indeterminate diastolic function (ID). With the progressive nature of HFpEF, diastolic function may change over time. However, the change of diastolic function, its predictor and prognosis in patients with clinically established HFpEF remains unknown.

Purpose

To investigate the clinical trajectory and outcomes of patients with HFpEF with ND or ID and to identify factors associated with progression from ND or ID at discharge to DD at 1-year follow-up.

Methods

Using data from a prospective multicenter observational study of patients with HFpEF, we extracted 289 patients with HFpEF with ND or ID at discharge who had echocardiographic data at 1-year follow-up for the re-evaluation of diastolic function. Diastolic function was assessed according to the 2016 American Society of Echocardiography recommendations. Patients were classified according to the absence or presence of progression from ND or ID to DD at 1 year. The primary endpoint was a composite of all-cause death and HF rehospitalization.

Results

Median age was 81 years, and 138 (47.8%) patients were female. At 1 year, 107 (37%) patients progressed to DD. During a median follow-up of 709 days, the composite endpoint occurred in 90 (31.1%) patients. Compared to patients without progression to DD, those with progression to DD had a significantly higher cumulative incidence rate of the composite endpoint (incidence rate: 11.7/100 person-year versus 23.3/100 person-year, P&lt;0.001). Progression to DD (adjusted HR: 2.014, 95% CI: 1.239–3.273, P=0.005) was independently associated with the composite endpoint. Age (adjusted OR: 1.046, 95% CI: 1.008–1.087, P=0.018), body mass index (BMI) (adjusted OR: 1.107, 95% CI: 1.029–1.192, P=0.006), and serum albumin (adjusted OR: 0.459, 95% CI: 0.216–0.974, P=0.042) were independently associated with progression from ND or ID to DD at 1 year.

Conclusion

More than one-third of patients with HFpEF with ND or ID progressed to DD at 1 year and had poor clinical outcomes. Age, BMI, and serum albumin were independently associated with this progression.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): This work was supported by grants from Japan Society for the Promotion of Science KAKENHI (No. JP 17K09496) and Japan Agency for Medical Research and Development (No. JP16lk1010013).

Association between prognosis and the use of angiotensin-converting enzyme inhibitors and/or angiotensin II receptor blocker in frail patients with heart failure with preserved ejection fraction

Background

The effectiveness of angiotensin-converting enzyme inhibitors (ACE-I) and angiotensin II receptor blockers (ARB) has not been demonstrated in patients with heart failure with preserved ejection fraction (HFpEF). We recently reported significant interaction between the use of ACE-I and/or ARB (ACE-I/ARB) and frailty on prognosis in patients with HFpEF.

Purpose

In the present study, we examined the association between ACE-I/ARB and prognosis in patients with HFpEF stratified by the presence or absence of frailty.

Methods

We examined the association between the use of ACE-I/ARB and prognosis according to the presence (Clinical Frailty Scale (CFS) ≥5) or absence (CFS ≤4) of frailty in patients with HFpEF in a post-hoc analysis of registry data. Primary endpoint was the composite of all-cause mortality and heart failure admission. Secondary endpoints were all-cause mortality and heart failure admission.

Results

Of 1059 patients, median age was 83 years and 45% were male. Kaplan-Meier analysis showed that the risk of composite endpoint (log-rank P=0.001) and all-cause death (log-rank P=0.005) in patients with ACE-I/ARB was lower in those with CFS ≥5, but similar between patients with and without ACE-I/ARB in patients with CFS ≤4 (composite endpoint: log-rank P=0.830; all-cause death: log-rank P=0.192). In a multivariable Cox proportional hazards model, use of ACE-I/ARB was significantly associated with lower risk of the composite endpoint (hazard ratio = 0.52, 95% CI: 0.33–0.83, P=0.005) and heart failure admission (hazard ratio = 0.45, 95% CI: 0.25–0.83, P=0.010) in patients with CFS ≥5, but not in patients with CFS ≤4 (composite endpoint: hazard ratio = 1.41, 95% CI: 0.99–2.02, P=0.059; heart failure admission: hazard ratio = 1.43, 95% CI: 0.94–2.18, P=0.091). The association between ACE-I or ARB and prognosis did not significantly differ by CFS (CFS ≤4: log-rank P=0.562; CFS ≥5: log-rank P=0.100, for with ACE-I vs. ARB, respectively). Adjusted HRs for CFS 1–4 were higher than 1.0, but were less than 1.0 at CFS 5.

Conclusions

In patients with HFpEF, use of ACE-I/ARB was associated with better prognosis in patients with frailty as assessed with the CFS, but not in those without frailty.

Funding Acknowledgement

Type of funding sources: Private company. Main funding source(s): Roche

Premature atrial contraction on Holter electrocardiogram predicts the recurrence of atrial fibrillation after catheter ablation

Introduction

It is important to detect the recurrence of atrial fibrillation (AF) after catheter ablation (CA) early, but the method of detection has not been established. The purpose of this study is to determine whether 24-h Holter electrocardiogram (ECG) can predict the recurrence of AF after CA.

Methods

We studied 336 patients of 497 patients enrolled in EARNEST-PVI trial to investigate whether the total number of premature atrial contraction (PAC) and the maximum number of PAC run by 24-h Holter ECG at 6 months after CA predicted AF recurrence after 6 months. We excluded 86 patients with recurrence by 6 months after CA and 75 patients without Holter ECG at 6 months after CA.

Results

Median age was 66 years, male were 77% and median follow-up period was 1138 days. Receiver operating characteristic curve analysis identified the total number of PAC ≥270 beats and the maximum number of PAC run ≥8 beats as the optimal cutoff for prediction of AF recurrence. Kaplan-Meier analysis showed patients with the total number of PAC ≥270 beats had more frequent AF recurrence than those without (Kaplan-Meier estimated 3-year AF recurrence rate 34% vs. 17%, Log-rank P=0.001) and patients with the maximum number of PAC run ≥8 beats had more frequent AF recurrence than those without (Kaplan-Meier estimated 3-year AF recurrence rate 33% vs. 20%, Log-rank P=0.006). Multivariate analysis revealed that the total number of PAC ≥270 beats and the maximum number of PAC run were significantly associated with AF recurrence (hazard ratio [95% confidence interval] 1.83 [1.16–2.91], P=0.01 and 1.01 [1.01–1.02], P=0.001, respectively)

Conclusion

The total number of PAC and the maximum number of PAC run on the Holter ECG may be useful in predicting AF recurrence after CA.

Funding Acknowledgement

Type of funding sources: None.

Secreted Glycosyltransferase RsIA_GT of Rhizoctonia solani AG-1 IA Inhibits Defense Responses in Nicotiana benthamiana

Anastomosis group AG-1 IA of Rhizoctonia solani Khün has a wide host range and threatens crop production. Various glycosyltransferases secreted by phytopathogenic fungi play an essential role in pathogenicity. Previously, we identified a glycosyltransferase RsIA_GT (AG11A_09161) as a secreted protein-encoding gene of R. solani AG-1 IA, whose expression levels increased during infection in rice. In this study, we further characterized the virulence function of RsIA_GT. It is conserved not only in Basidiomycota, including multiple anastomosis groups of R. solani, but also in other primary fungal taxonomic categories. RsIA_GT possesses a signal peptide (SP) for protein secretion, and its functionality was proven using yeast and Nicotiana benthamiana. The SP-truncated form of RsIA_GT (RsIA_GT(ΔS)) expressed in Escherichia coli-induced lesion-like phenotype in rice leaves when applied to punched leaves. However, Agrobacterium-mediated transient expressions of both the full-length RsIA_GT and RsIA_GT(ΔS) did not induce cell death in N. benthamiana leaves. Instead, only RsIA_GT(ΔS) suppressed the cell death induced by two reference cell death factors BAX and INF1 in N.benthamiana. RsIA_GT(ΔS)^{R154A D168A D170A}, a mutant RsIA_GT(ΔS) for the glycosyltransferase catalytic domain, still suppressed the BAX- or INF1-induced cell death, suggesting that the cell death suppression activity of RsIA_GT(ΔS) would be independent from its enzymatic activity. RsIA_GT(ΔS) also suppressed the H₂O₂ production and callose deposition and showed an effect on the induction of defense genes associated with the expression of BAX and INF1. The transient expression of RsIA_GT(ΔS) in N. benthamiana enhanced the lesion area caused by R. solani AG-1 IA. The secreted glycosyltransferase, RsIA_GT, of R. solani AG-1 IA is likely to have a dual role in virulence inside and outside of host cells.

Lateral transfers lead to the birth of momilactone biosynthetic gene clusters in grass

Momilactone A, an important plant labdane-related diterpenoid, functions as a phytoalexin against pathogens and an allelochemical against neighboring plants. The genes involved in the biosynthesis of momilactone A are found in clusters, i.e., momilactone A biosynthetic gene clusters (MABGCs), in the rice and barnyardgrass genomes. In addition, we know little about the origin and evolution of MABGCs. Here, we integrated results from comprehensive phylogeny and comparative genomic analyses of the core genes of MABGC-like clusters and MABGCs in 40 monocot plant genomes, providing convincing evidence for the birth and evolution of MABGCs in grass species. The MABGCs found in the PACMAD clade of the core grass lineage (including Panicoideae and Chloridoideae) originated from a MABGC-like cluster in Triticeae (BOP clade) via lateral gene transfer (LGT) and followed by recruitment of MAS1/2 and CYP76L1 genes. The MABGCs in Oryzoideae originated from PACMAD through another LGT event and lost CYP76L1 afterwards. The Oryza MABGC and another Oryza diterpenoid cluster c2BGC are two distinct clusters, with the latter originating from gene duplication and relocation within Oryzoideae. Further comparison of the expression patterns of the MABGC genes between rice and barnyardgrass in response to pathogen infection and allelopathy provides novel insights into the functional innovation of MABGCs in plants. Our results demonstrate LGT-mediated origination of MABGCs in grass and shed lights into the evolutionary innovation and optimization of plant biosynthetic pathways.

Transcriptional response of a target plant to benzoxazinoid and diterpene allelochemicals highlights commonalities in detoxification

BACKGROUND

Plants growing in proximity to other plants are exposed to a variety of metabolites that these neighbors release into the environment. Some species produce allelochemicals to inhibit growth of neighboring plants, which in turn have evolved ways to detoxify these compounds.

RESULTS

In order to understand how the allelochemical-receiving target plants respond to chemically diverse compounds, we performed whole-genome transcriptome analysis of Arabidopsis thaliana exposed to either the benzoxazinoid derivative 2-amino- 3H-phenoxazin-3-one (APO) or momilactone B. These two allelochemicals belong to two very different compound classes, benzoxazinoids and diterpenes, respectively, produced by different Poaceae crop species.

CONCLUSIONS

Despite their distinct chemical nature, we observed similar molecular responses of A. thaliana to these allelochemicals. In particular, many of the same or closely related genes belonging to the three-phase detoxification pathway were upregulated in both treatments. Further, we observed an overlap between genes upregulated by allelochemicals and those involved in herbicide detoxification. Our findings highlight the overlap in the transcriptional response of a target plant to natural and synthetic phytotoxic compounds and illustrate how herbicide resistance could arise via pathways involved in plant-plant interaction.

Difference in left atrial myocardial dynamics during reservoir phase between hypertrophic cardiomyopathy and hypertensive heart determined using three-dimensional speckle tracking echocardiography

We aimed to investigate left atrial (LA) myocardial dynamics during reservoir phase using three-dimensional speckle-tracking echocardiography (3DSTE) focusing on its longitudinal-circumferential relationship in patients with left ventricular (LV) hypertrophy and clarifying the difference in LA myocardial reservoir dynamics between hypertrophic cardiomyopathy (HCM) and hypertension with LV hypertrophy (HT-LVH). We studied 4 age-matched groups consisting of 27 patients with HCM, 16 with HT-LVH, 22 hypertensive patients without LV hypertrophy (HT), and 18 normal controls. Using 3DSTE, we measured LA global longitudinal strain (LA-LSR), global circumferential strain (LA-CSR), and global area strain (LA-ASR) during the reservoir phase, as well as LV global longitudinal strain (LV-LS), global circumferential strain (LV-CS), and global area strain (LV-AS). LA-LSR was significantly lower in the HCM and HT-LVH groups than in the controls, but there was no significant difference between the HCM and HT-LVH groups. LA-CSR and LA-ASR were significantly lower in the HCM group than in the other three groups, among which no significant difference was detected. In all subjects, LA-LSR was significantly correlated with LV-LS but not with LV-CS. LA-CSR was correlated with neither LV-LS nor LV-CS. In conclusion, both longitudinal and circumferential LA myocardial expansion during reservoir phase were reduced in HCM, while only the longitudinal one was reduced in HT-LVH. Reduction of LA circumferential expansion may reflect a more serious and intrinsic impairment of LA myocardial distensibility in HCM. Measuring LA-CSR and LA-ASR using 3DSTE would contribute to a more accurate understanding of LA reservoir function abnormality in HCM.

Chitooligosaccharide elicitor and oxylipins synergistically elevate phytoalexin production in rice

We show that in rice, the amino acid-conjugates of JA precursor, OPDA, may function as a non-canonical signal for the production of phytoalexins in coordination with the innate chitin signaling. The core oxylipins, jasmonic acid (JA) and JA-Ile, are well-known as potent regulators of plant defense against necrotrophic pathogens and/or herbivores. However, recent studies also suggest that other oxylipins, including 12-oxo-phytodienoic acid (OPDA), may contribute to plant defense. Here, we used a previously characterized metabolic defense marker, p-coumaroylputrescine (CoP), and fungal elicitor, chitooligosaccharide, to specifically test defense role of various oxylipins in rice (Oryza sativa). While fungal elicitor triggered a rapid production of JA, JA-Ile, and their precursor OPDA, rice cells exogenously treated with the compounds revealed that OPDA, rather than JA-Ile, can stimulate the CoP production. Next, reverse genetic approach and oxylipin-deficient rice mutant (hebiba) were used to uncouple oxylipins from other elicitor-triggered signals. It appeared that, without oxylipins, residual elicitor signaling had only a minimal effect but, in synergy with OPDA, exerted a strong stimulatory activity towards CoP production. Furthermore, as CoP levels were compromised in the OPDA-treated Osjar1 mutant cells impaired in the oxylipin-amino acid conjugation, putative OPDA-amino acid conjugates emerged as hypothetical regulators of CoP biosynthesis. Accordingly, we found several OPDA-amino acid conjugates in rice cells treated with exogenous OPDA, and OPDA-Asp was detected, although in small amounts, in the chitooligosaccharide-treated rice. However, as synthetic OPDA-Asp and OPDA-Ile, so far, failed to induce CoP in cells, it suggests that yet another presumed OPDA-amino acid form(s) could be acting as novel regulator(s) of phytoalexins in rice.

The rice wound-inducible transcription factor RERJ1 sharing same signal transduction pathway with OsMYC2 is necessary for defense response to herbivory and bacterial blight

This study describes biological functions of the bHLH transcription factor RERJ1 involved in the jasmonate response and the related defense-associated metabolic pathways in rice, with particular focus on deciphering the regulatory mechanisms underlying stress-induced volatile emission and herbivory resistance. RERJ1 is rapidly and drastically induced by wounding and jasmonate treatment but its biological function remains unknown as yet. Here we provide evidence of the biological function of RERJ1 in plant defense, specifically in response to herbivory and pathogen attack, and offer insights into the RERJ1-mediated regulation of metabolic pathways of specialized defense compounds, such as monoterpene linalool, in possible collaboration with OsMYC2-a well-known master regulator in jasmonate signaling. In rice (Oryza sativa L.), the basic helix-loop-helix (bHLH) family transcription factor RERJ1 is induced under environmental stresses, such as wounding and drought, which are closely linked to jasmonate (JA) accumulation. Here, we investigated the biological function of RERJ1 in response to biotic stresses, such as herbivory and pathogen infection, using an RERJ1-defective mutant. Transcriptome analysis of the rerj1-Tos17 mutant revealed that RERJ1 regulated the expression of a typical family of conserved JA-responsive genes (e.g., terpene synthases, proteinase inhibitors, and jasmonate ZIM domain proteins). Upon exposure to armyworm attack, the rerj1-Tos17 mutant exhibited more severe damage than the wildtype, and significant weight gain of the larvae fed on the mutant was observed. Upon Xanthomonas oryzae infection, the rerj1-Tos17 mutant developed more severe symptoms than the wildtype. Among RERJ1-regulated terpene synthases, linalool synthase expression was markedly disrupted and linalool emission after wounding was significantly decreased in the rerj1-Tos17 mutant. RERJ1 appears to interact with OsMYC2-a master regulator of JA signaling-and many OsJAZ proteins, although no obvious epistatic interaction was detected between them at the transcriptional level. These results indicate that RERJ1 is involved in the transcriptional induction of JA-mediated stress-responsive genes via physical association with OsMYC2 and mediates defense against herbivory and bacterial infection through JA signaling.

Aerial (+)-borneol modulates root morphology, auxin signalling and meristematic activity in Arabidopsis roots

One of the characteristic aspects of odour sensing in humans is the activation of olfactory receptors in a slightly different manner in response to different enantiomers. Here, we focused on whether plants showed enantiomer-specific response similar to that in humans. We exposed Arabidopsis seedlings to methanol (control) and (+)- or (-)-borneol, and found that only (+)-borneol reduced the root length. Furthermore, the root-tip width was more increased upon (+)-borneol exposure than upon (-)-borneol exposure. In addition, root-hair formation was observed near the root tip in response to (+)-borneol. Auxin signalling was strongly reduced in the root tip following exposure to (+)-borneol, but was detected following exposure to (-)-borneol and methanol. Similarly, in the root tip, the activity of cyclin B1:1 was detected on exposure to (-)-borneol and methanol, but not on exposure to (+)-borneol, indicating that (+)-borneol inhibits the meristematic activity in the root. These results partially explain the (+)-borneol-specific reduction in the root length of Arabidopsis. Our results indicate the presence of a sensing system specific for (+)-borneol in Arabidopsis.

Fibronectin plays a major role in hypoxia-induced lenvatinib resistance in hepatocellular carcinoma PLC/PRF/5 cells

Resistance to lenvatinib mesylate (LEN), a systemic chemotherapy that can be administered orally, has been a major issue for treatment of hepatocellular carcinoma (HCC). Although HCC is the tumor that most exhibits intratumoral hypoxia, which has been shown to be involved in the development of treatment resistance, there are no reports of LEN resistance in HCC treatment under hypoxia. The purpose of our study was to elucidate the mechanism of treatment resistance to LEN under hypoxia using HCC cell lines. We confirmed LEN resistance under hypoxic conditions in HCC cell lines. There was a significant increase in the IC₅₀ value of PLC/PRF/5 cells from 13.0±0.8 μM in normoxia to 21.3±1.1 μM in hypoxia, but in HepG2 cells, the increase was not significant. To elucidate the LEN resistance mechanism of PLC/PRF/5 cells under hypoxia, we performed microarray analysis and extracted genes that are thought to be related to this mechanism. Furthermore, in-silico analysis confirmed significant changes in the extracellular matrix, and among them, FN1 encoding fibronectin was determined as the hub of the gene cluster. The expression of fibronectin in PLC/PRF/5 cells examined with immunofluorescence staining was significantly elevated in and outside of cells under hypoxia, and tended to decrease when cells were exposed to LEN under normoxia. Furthermore, the fibronectin concentration in the culture solution of PLC/PRF/5 cells examined by ELISA was 2.3 times higher under hypoxia than under normoxia under LEN(-) conditions, and 1.6 times higher under hypoxia than under normoxia under LEN(+) conditions. It is assumed that in PLC/PRF/5 cells, fibronectin is probably suppressed as an indirect effect of LEN under normoxia, but transcription factors such as HIF-1α are induced under hypoxia, thus enhancing the production of fibronectin and attenuating the effect of LEN, resulting in drug resistance. This behavior of fibronectin with LEN exposure under hypoxia is probably specific to PLC/PRF/5 cells. Further studies should verify the combined effective inhibition of fibronectin and the MAPK pathway as a promising therapeutic strategy to enhance the value of LEN in HCC treatment.

A toxin-antitoxin system confers stability to the IncP-7 plasmid pCAR1

Toxin-antitoxin (TA) systems were initially discovered as plasmid addiction systems. Previously, our studies implied that the high stability of the IncP-7 plasmid pCAR1 in different Pseudomonas spp. hosts was due to the presence of a TA system on the plasmid. Bioinformatics approaches suggested that ORF174 and ORF175 could constitute a type II TA system, a member of the RES-Xre family, and that these two open reading frames (ORFs) constitute a single operon. As expected, the ORF175 product is a toxin, which decreases the viability of the host, P. resinovorans, while the ORF174 product functions as an antitoxin that counteracts the effect of ORF175 on cell growth. Based on these findings, we renamed ORF174 and ORF175 as prcA (antitoxin gene) and prcT (toxin gene), respectively. The prcA and prcT genes were cloned into the unstable plasmid vector pSEVA644. The recombinant vector was stably maintained in P. resinovorans and Escherichia coli cells under nonselective conditions following 6 days of daily subculturing. The empty vector (without the prcA and prcT genes) could not be maintained, which suggested that the PrcA/T system can be used as a tool to improve the stability of otherwise unstable plasmids in P. resinovorans and E. coli strains.

Visual echocardiographic scoring system of the left ventricular filling pressure and outcomes of heart failure with preserved ejection fraction

Aims

Elevated left ventricular filling pressure (LVFP) is a powerful indicator of worsening clinical outcomes in heart failure with preserved ejection fraction (HFpEF); however, detection of elevated LVFP is often challenging. This study aimed to determine the association between the newly proposed echocardiographic LVFP parameter, visually assessed time difference between the mitral valve and tricuspid valve opening (VMT) score, and clinical outcomes of HFpEF.

Methods and results

We retrospectively investigated 310 well-differentiated HFpEF patients in stable conditions. VMT was scored from 0 to 3 using two-dimensional echocardiographic images, and VMT ≥2 was regarded as a sign of elevated LVFP. The primary endpoint was a composite of cardiac death or heart failure hospitalization during the 2 years after the echocardiographic examination. In all patients, Kaplan–Meier curves showed that VMT ≥2 (n = 54) was associated with worse outcomes than the VMT ≤1 group (n = 256) (P < 0.001). Furthermore, VMT ≥2 was associated with worse outcomes when tested in 100 HFpEF patients with atrial fibrillation (AF) (P = 0.026). In the adjusted model, VMT ≥2 was independently associated with the primary outcome (hazard ratio 2.60, 95% confidence interval 1.46–4.61; P = 0.001). Additionally, VMT scoring provided an incremental prognostic value over clinically relevant variables and diastolic function grading (χ² 10.8–16.3, P = 0.035).

Conclusions

In patients with HFpEF, the VMT score was independently and incrementally associated with adverse clinical outcomes. Moreover, it could also predict clinical outcomes in HFpEF patients with AF.

Prognostic value of an echocardiographic index reflecting right ventricular operating stiffness in patients with heart failure

PURPOSE

We recently reported a noninvasive method for the assessment of right ventricular (RV) operating stiffness that is obtained by dividing the atrial-systolic descent of the pulmonary artery-RV pressure gradient (PRPGD_AC) derived from the pulmonary regurgitant velocity by the tricuspid annular plane movement during atrial contraction (TAPM_AC). Here, we investigated whether this parameter of RV operating stiffness, PRPGD_AC/TAPM_AC, is useful for predicting the prognosis of patients with heart failure (HF).

METHODS

We retrospectively included 127 hospitalized patients with HF who underwent an echocardiographic examination immediately pre-discharge. The PRPGD_AC/TAPM_AC was measured in addition to standard echocardiographic parameters. Patients were followed until 2 years post-discharge. The endpoint was the composite of cardiac death, readmission for acute decompensation, and increased diuretic dose due to worsening HF.

RESULTS

58 patients (46%) experienced the endpoint during follow-up. Univariable and multivariable Cox regression analyses demonstrated that the PRPGD_AC/TAPM_AC was associated with the endpoint. In a Kaplan-Meier analysis, the event rate of the greater PRPGD_AC/TAPM_AC group was significantly higher than that of the lesser PRPGD_AC/TAPM_AC group. In a sequential Cox analysis for predicting the endpoint's occurrence, the addition of PRPGD_AC/TAPM_AC to the model including age, sex, NYHA functional classification, brain natriuretic peptide level, and several echocardiographic parameters including tricuspid annular plane systolic excursion significantly improved the predictive power for prognosis.

CONCLUSION

A completely noninvasive index of RV operating stiffness, PRPGD_AC/TAPM_AC, was useful for predicting prognoses in patients with HF, and it showed an incremental prognostic value over RV systolic function.

Inflammation-frailty linkage and its long-term prognostic impact in patients with acute coronary syndrome

Introduction

Chronic inflammation has been receiving considerable attention as an emerging risk factor for cardiovascular disease. In contrast, with the aging of the population, frailty has been also attracting a great deal of attention as the residual risk for cardiovascular disease. Although inflammation and frailty exacerbate each other and have an adverse effect on many diseases, the relationship between chronic inflammation and frailty and the impact of these combination on long-term prognosis in patients with acute coronary syndrome (ACS) are not elucidated.

Purpose

The aims of this study were to determine the association between chronic inflammation and frailty and its impact on long-term cardiovascular outcomes in patients with ACS.

Methods

A total of 482 consecutive ACS patients with obstructive coronary artery disease (age 66±12 years, male 81%) were enrolled in this observational study. We evaluated patients' gait speed as a measure of frailty before discharge. C-reactive protein (CRP) levels at 1 month after discharge were also evaluated as inflammation in the chronic phase. According to commonly used criteria of the residual inflammation (CRP&gt;0.2 mg/dL) and the definition of the European Working Group for Sarcopenia (gait speed ≤0.8 m/sec), patients were stratified by 4 subgroups: low/high CRP with slow/normal gait speed. The primary endpoint was composite outcomes of cardiovascular death, myocardial infarction and ischemic stroke.

Results

While there was no significant association between CRP levels and gait speed in all patients, a significant negative association between two variables was observed in the high CRP group (Spearman's ρ = −0.31, p=0.001). During the median follow-up of 6 years, primary endpoints have occurred in 82 patients. Overall, event-free rates differed significantly among the 4 groups, demonstrating the lowest event-free rate in the patients with high CRP and slow gait speed (p&lt;0.0001; Figure). In the multivariate analysis, high CRP (adjusted HR 1.99, 95% CI 1.14–3.46, p=0.02) and slow gait speed (adjusted HR 1.82, 95% CI 1.09–3.04, p=0.02) were independently and significantly associated with the primary endpoint. Moreover, the patients with both high CRP and slow gait speed had a 2.6-fold higher risk of cardiovascular events compared to others (adjusted HR 2.62, 95% CI 1.36–5.05, p=0.004).

Conclusion

In the patients with ACS, CRP levels and gait speed were negatively associated in the high CRP group. Chronic inflammation and frailty were both associated with poor prognosis in ACS and in particular, the combination of these factors was strongly associated with poor prognosis.

Funding Acknowledgement

Type of funding sources: None. Figure 1

Application of the proximal isovelocity surface area method for estimation of the effective orifice area in aortic stenosis

Although the echocardiographic effective orifice area (EOA) calculated using the continuity equation is widely used for the assessment of severity in aortic stenosis (AS), the existence of high flow velocity at the left ventricular outflow tract (LVOT) potentially causes its overestimation. The proximal isovelocity surface area (PISA) method could be an alternative tool for the estimation of EOA that limits the influence of upstream flow velocity. EOA was calculated using the continuity equation (EOA_Cont) and PISA method (EOA_PISA), respectively, in 114 patients with at least moderate AS. The geometric orifice area (GOA) was also measured using the planimetry method in 51 patients who also underwent three-dimensional transesophageal echocardiography. Patients were divided into two groups according to the median LVOT flow velocity. EOA_PISA could be obtained in 108 of the 114 patients (95%). Although there was a strong correlation between EOA_Cont and EOA_PISA (r = 0.78, P < 0.001), EOA_Cont was statistically significantly larger than EOA_PISA (0.86 ± 0.33 vs 0.75 ± 0.29 cm², P < 0.001). Both EOA_Cont and EOA_PISA similarly correlated with GOA (r = 0.70, P < 0.001 and r = 0.77, P < 0.001, respectively). However, a fixed bias, which is hydrodynamically supposed to exist between EOA and GOA, was not observed between EOA_Cont and GOA. In contrast, there was a negative fixed bias between EOA_PISA and GOA with smaller EOA_PISA than GOA. The difference between EOA_Cont and GOA was significantly greater with a larger EOA_Cont relative to GOA in patients with high LVOT flow velocity than in those without (0.16 ± 0.25 vs - 0.07 ± 0.10 cm², P < 0.001). In contrast, the difference between EOA_PISA and GOA was consistent regardless of the LVOT flow velocity (- 0.07 ± 0.12 vs - 0.07 ± 0.15 cm², P = 0.936). The PISA method was applied to estimate EOA in patients with AS. EOA_PISA could be an alternative parameter for AS severity grading in patients with high LVOT flow velocity in whom EOA_Cont would potentially overestimate the orifice area.

Functional kaurene-synthase-like diterpene synthases lacking a gamma domain are widely present in Oryza and related species

Various diterpene synthases have been functionally identified in cultivated rice (Oryza sativa). These are the homologs of ent-copalyl diphosphate (ent-CDP) synthase and ent-kaurene synthase (KS) that are responsible for the biosynthesis of gibberellins, diterpenoid phytohormones. We isolated a cDNA encoding full-length OsKSL12, a previously uncharacterized KS like (KSL) enzyme that consists of a β-domain and an α-domain with an active center, but lacks an N-terminal γ-domain. Functional analysis using a bacterial expression system showed that recombinant OsKSL12 converted ent-CDP into ent-manool or ent-13-epi-manool. Comparative genomics revealed that functional OsKSL12 homologs exist in diverse wild species in the Oryzeae- Oryza nivara (Oryza rufipogon), Oryza coarctata, Oryza granulata, Leersia perrieri and Leersia tisseranti. KSL12 homologs in O. granulata, L. perrieri and L. tisseranti preferentially reacted with GGDP rather than ent-CDP, resulting in geranyllinalool rather than ent-manool or ent-13-epi-manool as the main product, meaning that KSL12 functionally diversified during evolution in the Oryzeae.

Azoxystrobin amine: A novel azoxystrobin degradation product from Bacillus licheniformis strain TAB7

Azoxystrobin (AZ) is a broad-spectrum synthetic fungicide widely used in agriculture globally. However, there are concerns about its fate and effects in the environment. It is reportedly transformed into azoxystrobin acid as a major metabolite by environmental microorganisms. Bacillus licheniformis strain TAB7 is used as a compost deodorant in commercial compost and has been found to degrade some phenolic and agrochemicals compounds. In this article, we report its ability to degrade azoxystrobin by novel degradation pathway. Biotransformation analysis followed by identification by electrospray ionization-mass spectrometry (MS), high-resolution MS, and nuclear magnetic resonance spectroscopy identified methyl (E)-3-amino-2-(2-((6-(2-cyanophenoxy)pyrimidin-4-yl)oxy)phenyl)acrylate, or (E)-azoxystrobin amine in short, and (Z) isomers of AZ and azoxystrobin amine as the metabolites of (E)-AZ by TAB7. Bioassay testing using Magnaporthe oryzae showed that although 40 μg/mL of (E)-AZ inhibited 59.5 ± 3.5% of the electron transfer activity between mitochondrial Complexes I and III in M. oryzae, the same concentration of (E)-azoxystrobin amine inhibited only 36.7 ± 15.1% of the activity, and a concentration of 80 μg/mL was needed for an inhibition rate of 56.8 ± 7.4%, suggesting that (E)-azoxystrobin amine is less toxic than the parent compound. To our knowledge, this is the first study identifying azoxystrobin amine as a less-toxic metabolite from bacterial AZ degradation and reporting on the enzymatic isomerization of (E)-AZ to (Z)-AZ, to some extent, by TAB7. Although the fate of AZ in the soil microcosm supplemented with TAB7 will be needed, our findings broaden our knowledge of possible AZ biotransformation products.

Influence of left ventricular systolic dysfunction on occurrence of pulsus tardus in patients with aortic stenosis

BACKGROUND

Although the time difference between peak of left ventricular (LV) and aortic systolic pressures (T_LV-Ao), which is considered to in part reflect pulsus tardus, is reported to be associated with clinical outcome in aortic stenosis (AS), its physiological determinants remain to be elucidated. We hypothesized that not only AS severity but also LV systolic dysfunction could be associated with occurrence of pulsus tardus.

METHODS

T_LV-Ao was measured by simultaneous LV and aortic pressure tracing in 74 AS patients and prolonged T_LV-Ao was defined as ≥66 ms according to the previous report. Mean transaortic valvular pressure gradient (mPG) and effective orifice area index (EOAI) were estimated by Doppler echocardiography and severe AS was defined as EOAI ≤0.60 cm²/m². Global longitudinal strain (GLS) was measured by using speckle-tracking method.

RESULTS

Although a weak correlation was observed between EOAI and T_LV-Ao, there was substantial population showing discordance between the parameters: severe AS despite normal T_LV-Ao (10 of 47 patients) and moderate AS despite prolonged T_LV-Ao (9 of 17 patients). In severe AS, mPG was significantly higher in patients showing prolonged T_LV-Ao (57±20 vs 36±10 mmHg, p<0.0001) whereas GLS was comparable between the groups (-15.2±3.5% vs -14.8±3.2%). In contrast, in moderate AS, GLS was significantly smaller in patients showing prolonged T_LV-Ao (-12.6±4.7% vs -17.4±3.4%, p=0.0271) while mPG was comparable (34±7 mmHg vs 35±8 mmHg). Multivariable analysis revealed that not only mPG but also GLS was an independent determinant of T_LV-Ao.

CONCLUSIONS

The occurrence of pulsus tardus could be associated with not only AS severity but also LV systolic dysfunction in AS patients.

Genome-wide Screening of Genes Associated with Momilactone B Sensitivity in the Fission Yeast

Momilactone B is a natural product with dual biological activities, including antimicrobial and allelopathic properties, and plays a major role in plant chemical defense against competitive plants and pathogens. The pharmacological effects of momilactone B on mammalian cells have also been reported. However, little is known about the molecular and cellular mechanisms underlying its broad bioactivity. In this study, the genetic determinants of momilactone B sensitivity in yeast were explored to gain insight into its mode of action. We screened fission yeast mutants resistant to momilactone B from a pooled culture containing genome-wide gene-overexpressing strains in a drug-hypersensitive genetic background. Overexpression of pmd1, bfr1, pap1, arp9, or SPAC9E9.06c conferred resistance to momilactone B. In addition, a drug-hypersensitive, barcoded deletion library was newly constructed and the genes that imparted altered sensitivity to momilactone B upon deletion were identified. Gene Ontology and fission yeast phenotype ontology enrichment analyses predicted the biological pathways related to the mode of action of momilactone B. The validation of predictions revealed that momilactone B induced abnormal phenotypes such as multiseptated cells and disrupted organization of the microtubule structure. This is the first investigation of the mechanism underlying the antifungal activity of momilactone B against yeast. The results and datasets obtained in this study narrow the possible targets of momilactone B and facilitate further studies regarding its mode of action.

Functional significance of intra-left ventricular vortices on energy efficiency in normal, dilated, and hypertrophied hearts

PURPOSE

To investigate the influence of changes in vortices within the left ventricle (LV) on energy efficiency (EE) in normal and diseased hearts.

METHODS

We performed vector flow mapping echocardiography in 36 normal participants (N), 36 patients with dilated cardiomyopathy (D), and 36 patients with LV hypertrophy (H). The circulation of the main anterior vortex was measured as a parameter of vortex strength. Energy loss (EL) was measured for one cardiac cycle, and EE was calculated as EL divided by stroke work (SW), which represents the loss of kinetic energy per unit of LV external work.

RESULTS

Circulation increased in the order of N, H, and D (N: 15 ± 4, D: 19 ± 8, H: 17 ± 6 × 10^-3 m² /s; analysis of variance [ANOVA] P < .01). Conversely, EE increased in the order of N, D, and H (N: 0.22 ± 0.07, D: 0.26 ± 0.16, H: 0.30 ± 0.16 10^-5 J/mm Hg mL m s; ANOVA P = .04), suggesting worst EE in group H. We found a positive correlation between circulation and SW only in group N, and positive correlation between circulation and EE only in diseased groups (D: R = 0.55, P < .01; H: R = 0.44, P < .01). Multivariable analyses revealed that circulation was the independent determinant of EE in groups D and H.

CONCLUSIONS

Enhanced vortices could be associated with effective increase in LV external work in normal hearts. Conversely, they were associated with loss of EE without an optimal increase in external work in failing hearts, regardless of the LV morphology.

Acetic-acid-induced jasmonate signaling in root enhances drought avoidance in rice

Conferring drought resistant traits to crops is one of the major aims of current breeding programs in response to global climate changes. We previously showed that exogenous application of acetic acid to roots of various plants could induce increased survivability under subsequent drought stress conditions, but details of the metabolism of exogenously applied acetic acid, and the nature of signals induced by its application, have not been unveiled. In this study, we show that rice rapidly induces jasmonate signaling upon application of acetic acid, resulting in physiological changes similar to those seen under drought. The major metabolite of the exogenously applied acetic acid in xylem sap was determined as glutamine-a common and abundant component of xylem sap-indicating that acetic acid is not the direct agent inducing the observed physiological responses in shoots. Expression of drought-responsive genes in shoot under subsequent drought conditions was attenuated by acetic acid treatment. These data suggest that acetic acid activates root-to-shoot jasmonate signals that partially overlap with those induced by drought, thereby conferring an acclimated state on shoots prior to subsequent drought.

Multicenter prospective trial of total gastrectomy versus proximal gastrectomy for upper third cT1 gastric cancer

BACKGROUND

The appropriate surgical procedure for patients with upper third early gastric cancer is controversial. We compared total gastrectomy (TG) with proximal gastrectomy (PG) in this patient population.

METHODS

A multicenter, non-randomized trial was conducted, with patients treated with PG or TG. We compared short- and long-term outcomes between these procedures.

RESULTS

Between 2009 and 2014, we enrolled 254 patients from 22 institutions; data from 252 were included in the analysis. These 252 patients were assigned to either the PG (n = 159) or TG (n = 93) group. Percentage of body weight loss (%BWL) at 1 year after surgery, i.e., the primary endpoint, in the PG group was significantly less than that of the TG group (- 12.8% versus - 16.9%; p = 0.0001). For short-term outcomes, operation time was significantly shorter for PG than TG (252 min versus 303 min; p < 0.0001), but there were no group-dependent differences in blood loss and postoperative complications. For long-term outcomes, incidence of reflux esophagitis in the PG group was significantly higher than that of the TG group (14.5% versus 5.4%; p = 0.02), while there were no differences in the incidence of anastomotic stenosis between the two (5.7% versus 5.4%; p = 0.92). Overall patient survival rates were similar between the two groups (3-year survival rates: 96% versus 92% in the PG and TG groups, respectively; p = 0.49).

CONCLUSIONS

Patients who underwent PG were better able to control weight loss without worsening the prognosis, relative to those in the TG group. Optimization of a reconstruction method to reduce reflux in PG patients will be important.

Influence of advanced pulmonary vascular remodeling on accuracy of echocardiographic parameters of left ventricular filling pressure

Evaluation of left ventricular filling pressure plays an important role in the clinical management of pulmonary hypertension. However, the accuracy of echocardiographic parameters for the determination of left ventricular filling pressure in the presence of pulmonary vascular lesions has not been fully addressed. We retrospectively investigated 124 patients with pulmonary hypertension due to pulmonary vascular lesions (noncardiac pulmonary hypertension group) and 113 patients with ischemic heart disease (control group) who underwent right heart catheterization and echocardiography. The noncardiac pulmonary hypertension group was subdivided into less-advanced and advanced groups according to median pulmonary vascular resistance. Pulmonary artery wedge pressure was determined as left ventricular filling pressure. As echocardiographic parameters of left ventricular filling pressure, the ratio of early- (E) to late-diastolic transmitral flow velocity (E/A), ratio of E to early-diastolic mitral annular velocity (E/e′), and left atrial volume index were measured. In the less-advanced noncardiac pulmonary hypertension and control groups, positive correlations were observed between pulmonary artery wedge pressure and late-diastolic transmitral flow velocity (R = 0.41, P = 0.002 and R = 0.71, P < 0.001, respectively) and left atrial volume index (R = 0.53, P < 0.001 and R = 0.41, P < 0.001), whereas in the advanced noncardiac pulmonary hypertension group, pulmonary artery wedge pressure was only correlated with left atrial volume index (R = 0.27, P = 0.032). In the controls, only pulmonary artery wedge pressure determined E (β = 0.48, P < 0.001), whereas both pulmonary artery wedge pressure and pulmonary vascular resistance were independent determinants of E (β = 0.29, P < 0.001 and β = –0.28, P = 0.001, respectively) in the noncardiac pulmonary hypertension group. In conclusion, in the presence of advanced pulmonary vascular lesions, conventional echocardiographic parameters may not accurately reflect left ventricular filling pressure. Elevated pulmonary vascular resistance would lower the E, even when pulmonary artery wedge pressure is elevated, resulting in blunting of echocardiographic parameters for the detection of elevated left ventricular filling pressure.

Dietary Patterns and Muscle Mass, Muscle Strength, and Physical Performance in the Elderly: A 3-Year Cohort Study

OBJECTIVES

Nutritional support effectively prevents and treats sarcopenia; however, the influence of overall dietary patterns on sarcopenia parameters is less investigated. This study aimed to determine the association between adherence to Mediterranean-style diet (MD), Dietary Approaches to Stop Hypertension (DASH), Japanese Food Guide Spinning Top (JFG-ST), and modified JFG-ST (mJFG-ST) and muscle mass, muscle strength, and physical performance in community-dwelling Japanese elderly.

DESIGN AND SETTINGS

This prospective cohort study recruited individuals aged over 60 years from a community college in Nagoya, Japan.

PARTICIPANTS AND MEASUREMENTS

A total of 666 participants were followed up annually from 2014 to 2017. Demographic data, anthropometric measurements, and sarcopenia parameters including walking speed (WS), hand grip strength in the dominant hand (HGS), and skeletal mass index (SMI) were recorded. Self-recall dietary intake was assessed using a validated food frequency questionnaire comprising 29 food groups. Adherence to MD, DASH, JFG-ST, and mJFG-ST was determined by tertiles.

RESULTS

At baseline, the mean age of all participants (56.5% women) was 69.4±4.4 years. WS, HGS, and SMI were 1.4±0.2 (m/s), 28.9±8.1 (kg), and 6.7±1.0 (kg/m2), respectively. In longitudinal analysis, participants with higher JFG-ST adherence scores were more likely to have higher SMI (Q3 vs. Q1: mean difference, 0.048; p=0.04) after adjustment, and its benefits were more evident in men (Q2 vs. Q1: mean difference, 0.098; p=0.047; Q3 vs. Q1: mean difference, 0.091; p=0.017) than in women. WS and HGS were not associated with any type of dietary pattern.

CONCLUSIONS

Adherence to JFG-ST was positively associated with SMI in Japanese community-dwelling elderly adults aged over 60 years, specifically in men. The country-specific dietary recommendations are required to be developed for sarcopenia prevention.

Deep Learning-Based Nuclear Lobe Count Method for Differential Count of Neutrophils

Differentiating neutrophils based on the count of nuclear lobulation is useful for diagnosing various hematological disorders, including megaloblastic anemia, myelodysplastic syndrome, and sepsis. It has been reported that one-fifth of sepsis-infected patients worldwide died between 1990 and 2017. Notably, fewer nuclear-lobed and stab-formed neutrophils develop in the peripheral blood during sepsis. This abnormality can serve as an early diagnostic criterion. However, testing this feature is a complex and time-consuming task that is rife with human error. For this reason, we apply deep learning to automatically differentiate neutrophil and nuclear lobulation counts and report the world's first small-scale pilot. Blood films are prepared using venous peripheral blood taken from four healthy volunteers and are stained with May-Grünwald Giemsa stain. Six-hundred 360 × 363-pixel images of neutrophils having five different nuclear lobulations are automatically captured by Cellavision DM-96, an automatic digital microscope camera. Images are input to an original architecture with five convolutional layers built on a deep learning neural-network platform by Sony, Neural Network Console. The deep learning system distinguishes the four groups (i.e., band-formed, two-, three-, and four- and five- segmented) of neutrophils with up to 99% accuracy, suggesting that neutrophils can be automatically differentiated based on their count of segmented nuclei using deep learning.

Deciphering OPDA Signaling Components in the Momilactone-Producing Moss Calohypnum plumiforme

Jasmonic acid (JA) and its biologically active form jasmonoyl-L-isoleucine (JA-Ile) regulate defense responses to various environmental stresses and developmental processes in plants. JA and JA-Ile are synthesized from α-linolenic acids derived from membrane lipids via 12-oxo-phytodienoic acid (OPDA). In the presence of JA-Ile, the COI1 receptor physically interacts with JAZ repressors, leading to their degradation, resulting in the transcription of JA-responsive genes by MYC transcription factors. Although the biosynthesis of JA-Ile is conserved in vascular plants, it is not recognized by COI1 in bryophytes and is not biologically active. In the liverwort Marchantia polymorpha, dinor-OPDA (dn-OPDA), a homolog of OPDA with two fewer carbons, and its isomer dn-iso-OPDA accumulate after wounding and are recognized by COI1 to activate downstream signaling. The moss Calohypnum plumiforme produces the antimicrobial-specialized metabolites, momilactones. It has been reported that JA and JA-Ile are not detected in C. plumiforme and that OPDA, but not JA, can induce momilactone accumulation and the expression of these biosynthetic genes, suggesting that OPDA or its derivative is a biologically active molecule in C. plumiforme that induces chemical defense. In the present study, we investigated the biological functions of OPDA and its derivatives in C. plumiforme. Searching for the components potentially involving oxylipin signaling from transcriptomic and genomic data revealed that two COI1, three JAZ, and two MYC genes were present. Quantification analyses revealed that OPDA and its isomer iso-OPDA accumulated in larger amounts than dn-OPDA and dn-iso-OPDA after wounding. Moreover, exogenously applied OPDA, dn-OPDA, or dn-iso-OPDA induced the transcription of JAZ genes. These results imply that OPDA, dn-OPDA, and/or their isomers potentially act as biologically active molecules to induce the signaling downstream of COI1-JAZ. Furthermore, co-immunoprecipitation analysis showed the physical interaction between JAZs and MYCs, indicating the functional conservation of JAZs in C. plumiforme with other plants. These results suggest that COI1-JAZ-MYC mediated signaling is conserved and functional in C. plumiforme.

The second pharyngeal pouch is generated by dynamic remodeling of endodermal epithelium in zebrafish

Pharyngeal arches (PAs) are segmented by endodermal outpocketings called pharyngeal pouches (PPs). Anterior and posterior PAs appear to be generated by different mechanisms, but it is unclear how the anterior and posterior PAs combine. Here, we addressed this issue with precise live imaging of PP development and cell tracing of pharyngeal endoderm in zebrafish embryos. We found that two endodermal bulges are initially generated in the future second PP (PP2) region, which separates anterior and posterior PAs. Subsequently, epithelial remodeling causes contact between these two bulges, resulting in the formation of mature PP2 with a bilayered morphology. The rostral and caudal bulges develop into the operculum and gill, respectively. Development of the caudal PP2 and more posterior PPs is affected by impaired retinoic acid signaling or pax1a/b dysfunction, suggesting that the rostral front of posterior PA development corresponds to the caudal PP2. Our study clarifies an aspect of PA development that is essential for generation of a seamless array of PAs in zebrafish.

Clinical significance of late diastolic tissue doppler parameters after onset of STEMI: from the view point of the timing of the echocardipography

Background

The early transmitral flow velocity (E) divided by the early diastolic velocity of the mitral valve annulus (e') is referred to as the “E/e' ratio,” is useful even for ST elevation acute myocardial infarction (STEMI). However, the role of late diastolic velocity (a') which reveals the atrial function for STEMI is still unclear.

Objectives

We evaluated the clinical usefulness of tissue Doppler including atrial function for a first-time STEMI by long time follow up. Furthermore, we evaluated the meaning of each parameters by performing immediately after PCI or 2 weeks later.

Methods

We treated consecutive 571 first-time STEMI patients by immediate PCI within 12 hours after onset, and we examined 270 patients at immediately after PCI (GroupA, 65 years, 250 male) and 301 patients at 2 weeks after onset (GroupB, 64 years, 243 male). We examined trans mitral flow and TDI, then defined E/e' as LV filling pressure and A/a' as left atrial function. We followed them for a long time (&gt;5 years). The primary end point (PE) was cardiac death or re-admission for heart failure (HF).

Results

We followed the patients in Group A for 10 years, Group B for 5 years. PE occurred in 64 patients in GroupA during 10 years, and 45 patients in GroupB during 5 years. We analyzed the univariate and multivariate Cox hazard analyses and we compared e' and a', E/e' and A/a' (Table). In GroupA, a' and A/a' were the independent predictors, on the other hand neither a' nor A/a' were the predictors in GroupB. E/e' was an independent predictor both in GroupA and B.

Conclusion

TDI parameters have different meanings by the timing of echocardiography after onset of a first-time STEMI. These results demonstrated that atrial dysfunction immediately after onset of STEMI suggests the poor prognosis after STEMI.

Cox Hazard Proportional Analysis

Funding Acknowledgement

Type of funding source: None