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Objective: To evaluate whether the change in computed tomography pulmonary angiography (CTPA) metrics after balloon pulmonary angioplasty (BPA) can predict treatment effect in chronic thromboembolic pulmonary hypertension (CTEPH) patients. Methods: This study included 82 CTEPH patients who underwent both CTPA and right heart catheterization (RHC) before and at the scheduled time of 6 months after BPA. The diameters of the main pulmonary artery (dPA), ascending aorta (dAA), right atrium (dRA), right ventricular free wall thickness (dRVW), and right and left ventricles (dRV, dLV) were measured on CTPA. The correlation of the New York Heart Association functional class (NYHA FC), 6-minute walking distance (6MWD), brain natriuretic peptide (BNP) level, and calculated CT metrics with a decrease in mean pulmonary artery pressure (ΔmPAP) using RHC (used as the reference for BPA effect) was investigated. Using multiple regression analysis, independent variables were also identified. Results: In univariate analysis, clinical indicators (NYHA FC, 6MWD, and BNP level) improved significantly after BPA and were significantly correlated with ΔmPAP (p < 0.01). In the univariate analysis of CTPA parameters, dPA, dRA, dPA/dAA ratio, dRVW, and dRV/dLV ratio decreased significantly and were significantly correlated with ΔmPAP (p < 0.01). Multivariate analysis demonstrated that decreased dPA (p = 0.001) and decreased dRA (p = 0.039) on CTPA were independent predictive factors of ΔmPAP. Conclusions: Decreased dPA and dRA on CTPA could predict a decrease in mPAP after BPA, thus potentially eliminating unnecessary invasive catheterization. Key Points: • The reduction in mean pulmonary artery pressure after balloon pulmonary angioplasty in CTEPH patients was significantly correlated with the clinical indices improvement and CTPA parameter decrease. • The decreased diameter of the main pulmonary artery and the decreased diameter of the right atrium on CTPA were independent predictors of mean pulmonary artery pressure reduction. [ABSTRACT FROM AUTHOR]

Topological properties in material science have recently received tremendous attention, as exemplified by topological insulators. As for quantum spin systems, the Haldane chain with integer spins is the best known example1. The realization of a topological quantum phase in the Haldane chain is an innovative research development related to the 2016 Nobel Prize in Physics. For mixed spin chains composed of two different spins, the appearance of a topologically quantized magnetization plateau is predicted by the Lieb-Mattis theorem2 in combination with the Oshikawa-Yamanaka-Affleck criterion3. However, the actual magnetization plateau in the mixed spin chain has not yet been observed. Here, we present a model compound forming a mixed spin-(1/2, 5/2) chain. We observe a clear Lieb-Mattis plateau and well explain it quantitatively. The present results demonstrate a quantum many-body effect based on quantum topology and provide a new stage in the search for topological properties in condensed matter physics. [ABSTRACT FROM AUTHOR]

Takotsubo cardiomyopathy (TC) is characterized by transient wall motion abnormalities most commonly involving the left ventricle (LV). Although biventricular TC had been considered uncommon condition, recently biventricular TC has been reported as a new variant observed in 19–42% of all TC presentations. Since biventricular TC has a poor prognosis as compared with isolated TC, it is important to distinguish between isolated LV TC and biventricular TC. We present a case of 70-year-old female with dyspnea persisting for 2 days. Electrocardiogram showed symmetrical T-wave inversion in leads V2–V4. Transthoracic echocardiography (TTE) revealed diffuse hypo-kinesis except for the apical inferior LV and LV ejection fraction of 32%. Hyper-kinesis of the right ventricular (RV) basal segment and dys-kinesis of the RV apical segment. 2 weeks after admission, coronary angiography showed no evidence of significant stenosis. LV ejection fraction improved to 51% and wall motion abnormalities of the RV basal and apical segments were ameliorated to normo-kinesis. Electrocardiogram revealed symmetrical and deepened T-wave inversion in leads V2–V3. The presence of a transient abnormality in biventricular wall motion beyond a single coronary artery perfusion territory with new electrocardiographic change met the diagnostic criteria of definite TC defined by Mayo Clinic criteria. 4 weeks after admission, no recurrence of wall motion abnormalities in both ventricles were found and T-wave inversion ameliorated. To our knowledge, this is the first report of biventricular TC with asymmetrical abnormities of wall motion between LV and RV. [ABSTRACT FROM AUTHOR]

Balloon pulmonary angioplasty (BPA) has emerged as a new treatment strategy for patients with chronic thromboembolic pulmonary hypertension (CTEPH). Improvements in hemodynamic parameters after BPA have been reported, but some patients continue to suffer from reduced exercise tolerance even after the normalization of hemodynamic parameters following BPA. As the amelioration of hemodynamic parameters is reportedly achieved via BPA, we hypothesized that the limiting factors for exercise tolerance in these patients are related to respiratory function. Therefore, we investigated the associations between respiratory function and exercise tolerance, and the mechanisms underlying respiratory dysfunction in patients after BPA. We analyzed 62 patients with CTEPH who underwent 1-year follow-up after BPA. Predictors for reduced exercise tolerance after BPA determined with six-minute walk test were sought from pulmonary hemodynamic and respiratory parameters using logistic regression analysis. After multivariate adjustments, high mean right atrium pressure (mRAP) and high alveolar-arterial oxygen gradient (A-aDO2) were significant predictors for reduced exercise tolerance. Next, we analyzed factors associated with high A-aDO2. Among the pathophysiological causes of high A-aDO2, including ventilation, diffusing capacity, and low ventilation-perfusion ratio, only low ventilation-perfusion ratio caused by high intrapulmonary shunt fraction was associated with high A-aDO2. Impaired oxygenation due to residual high intrapulmonary shunt fraction was associated with reduced exercise tolerance in patients with CTEPH, after receiving BPA. [ABSTRACT FROM AUTHOR]

Balloon pulmonary angioplasty (BPA) has emerged as an effective treatment for patients with inoperable chronic thromboembolic pulmonary hypertension (CTEPH). Renal function has been identified as a prognostic marker in patients with pulmonary hypertension in previous studies. We, therefore, aimed to investigate the clinical parameters associated with improvements in renal function in patients with CTEPH. A total of 45 consecutive patients with inoperable CTEPH undergoing BPA (mean age 62.2 ± 15.1 years) were included in the study. We evaluated the patients' clinical characteristics at baseline and at 1-year post-BPA, and investigated the association between renal function and hemodynamic parameters, including right heart function. Hemodynamics and renal function showed sustained improvements at 1 year after BPA in 64.4% of patients. Improved estimated glomerular filtration rate (eGFR) was significantly correlated with increased cardiac index (r = 0.433, p = 0.003) and mixed venous oxygen saturation (SvO2; r = 0.459, p = 0.002), and with decreased mean pulmonary arterial pressure (r = − 0.420, p = 0.004) and pulmonary vascular resistance (r = -− 0.465, p = 0.001). Multivariate analysis revealed that an increase in SvO2 immediately after the final BPA was associated with improved eGFR after the 1st year (odds ratio 1.041; 95% confidence interval 1.004–1.078; P = 0.027). The cut-off value for predicting improved eGFR was an increase in SvO2 after the final BPA of >125.4% over the baseline value (specificity 100%, sensitivity 24.1%). In conclusion, BPA improved symptoms, right heart function, hemodynamics, and renal function up to the chronic phase. Increasing SvO2 by >125.4% above baseline in the acute phase is important for improving renal function at 1 year after BPA in CTEPH patients. [ABSTRACT FROM AUTHOR]

Chronic thromboembolic pulmonary hypertension (CTEPH) has a poor prognosis because of the associated progressive right heart failure. Accurate evaluation of right ventricular (RV) function would thus be useful to predict prognosis. However, the significance of RV diastolic function remains unclear. We aimed to identify which echocardiographic measures are most accurate, and potentially useful, in assessing RV diastolic function in patients with CTEPH, and to study the effects of balloon pulmonary angioplasty (BPA) on them. We enrolled 53 CTEPH patients who underwent BPA. Echocardiographic parameters, including two-dimensional speckle-tracking echocardiography, were compared to the hemodynamic parameters measured by right heart catheterization before and after BPA. RV strain rate during early diastole (SR_E), tricuspid e' and right atrial area (RAA) were ameliorated after BPA, concomitant with a decrease in the time constant of the RV pressure curve during diastole (tau), indicating the improvement of RV diastolic function. Among them, SR_E had the strongest correlation with tau (r = - 0.39, p < 0.001). Furthermore, the receiver operating characteristic analyses revealed that E/SR_E (AUC 0.704) and inferior vena cava diameter (AUC 0.726) had a stronger association with higher mean right atrial pressure than RAA (AUC 0.632). In contrast, RAA had a stronger correlation with 6 min-walk distances than SR_E (r = - 0.39, p < 0.001 vs. r = 0.30, p = 0.005). Taken together, echocardiographic assessment of RV diastolic function might be associated with hemodynamics as well as exercise tolerance in patients with CTEPH, indicating its benefits in evaluating the therapeutic effects of BPA. [ABSTRACT FROM AUTHOR]

This paper describes a behavior acquisition of virtual robots by evolving artificial neural network (EANN) with a gradual learning. The gradual learning is a method in which initial states of simulation for evaluation is changing as optimization progresses. Motion of virtual robot is calculated by the physical engine PhysX, and it is controlled by an ANN. Parameters of an ANN are optimized by particle swarm optimization (PSO) so that a virtual robot follows the given target. Experimental results show that the gradual learning is better than a common learning method, realizing the standing behaviors which are not acquired by a common learning at all. It is also shown that random initialization of solutions in the middle of optimization leads to better behaviors. [ABSTRACT FROM AUTHOR]

The proportion of elderly acute coronary syndrome (ACS) patients who receive optimal medical therapy (OMT) after percutaneous coronary intervention (PCI) and whether OMT affects their long-term outcomes remain unclear. We retrospectively investigated 405 ACS patients who underwent stent implantation between 2005 and 2009, and compared the outcomes between patients <80 years of age vs. ≥80 years of age. The prescription rate of the recommended medical agents for ACS in both groups during hospitalization and 2 years after admission was also retrieved. Among the enrolled study population, 75 patients (19%) were aged ≥80 years. These elderly patients had a higher 2-year mortality compared with patients aged <80 years group. The prescription rate of beta-blockers, angiotensin-blocking drugs, and statins tended to be lower in patients aged ≥80 years than in those aged <80 years. Furthermore, among patients ≥80 years of age, those who received OMT had better clinical outcome of 2-year mortality compared to those without OMT. Elderly patients with ACS treated by PCI are at substantially higher risk of adverse events than younger patients. However, they are less likely to receive OMT. PCI with OMT might improve the clinical outcomes of elderly ACS patients. [ABSTRACT FROM AUTHOR]

Percutaneous closure of atrial septal defect has been accepted as an effective and safe treatment. So far, there has been no procedure-related mortality in Japan. However, device embolization is one of the major complications related to the procedure. We report successful retrieval of an Amplatzer septal occluder embolized and impacted in the pulmonary artery using an ablation catheter and a triple-loop snare device. [ABSTRACT FROM AUTHOR]

Transcatheter closure of secundum atrial septal defect (ASD) has been widely performed as a less invasive alternative to surgery with zero mortality so far in Japan. In the US and Europe, intracardiac echocardiography (ICE) has replaced transesophageal echocardiography (TEE) as a primary imaging tool during percutaneous ASD closure. However, the experience of ICE in ASD closure is limited in Japan. Consecutive 51 patients underwent percutaneous ASD closure with ICE guidance. Clinical results were compared to those of 41 patients who underwent ASD closure with TEE guidance. Pediatric patients and patients with multiple ASDs who were expected to need multiple devices were excluded. Success rate was similar in both groups (ICE 96.1 %, TEE 92.7 %). Catheterization laboratory time was significantly shortened with ICE than with TEE (131 vs. 155 min, p = 0.0003). There were no complications related to the use of ICE. ICE-guided ASD closure is feasible in most adult patients. ICE is superior to TEE in shortening catheterization laboratory time and eliminating general anesthesia, and can potentially replace TEE as the primary image guide during percutaneous ASD closure. [ABSTRACT FROM AUTHOR]

First principle calculations of the effective exchange integrals ( J) in the Heisenberg model for diradical species are presented for both symmetry-adapted multi-reference (MR) and single-reference broken-symmetry (BS) methods. The Mukherjee-type state-specific MR coupled cluster singles and doubles (MkCCSD) method with several different reference orbitals including BS natural orbitals is used to calculate the singlet-triplet energy gaps (S-T energy gap or 2 J) and diradical characters for the antiaromatic molecules [ a cyclopropenyl anion (CPA), b cyclobutadiene (CBD), and c cyclopentadienyl cation (CPC)], the cyclobutadiene derivatives with polar substitutents [ d aminocyclobutadiene (ACBD), e formylcyclobutadiene (FCBD), and f 1-amino-2-formyl-cyclobutadiene (AFCBD)] and finally the cyclobutadine derivatives with radical substitutents [ g 1,2-bis(methylene)cyclobutadiene (1,2-BMCBD) and h 1,3-bis(methylene)cyclobutadiene (1,3-BMCBD)]. For the BS methods, the spin-unrestricted Hartree-Fock based CCSD (UHF-CCSD), the CCD with the spin-unrestricted Brueckner determinant (UBD), and BS density functional theory (UDFT) computations are performed. Comparison between MkCCSD and the UHF-CCSD results indicates that spin-contamination of UHF-CCSD solutions still remains. In comparison with UHF-CCSD, the UBD results show that spin-contamination involved in BS solutions is greatly suppressed. To eliminate the spin contamination, an approximate spin-projection (AP) scheme is applied to the BS solutions. The AP procedure with the use of the expectation value of the total-spin operator corresponding to UHF-CCSD and UBD results yields good agreement with the MkCCSD results. As for the AP correction of the UDFT methods, three different computational schemes for predicting the expectation value of the total-spin operator are examined. Systematic comparisons between these methods are presented for the S-T energy gaps (2 J). Implications of the present computational results have been discussed in relation to the design of magnetic oligomers and polymers. [ABSTRACT FROM AUTHOR]

It is reported that Pd–Pt core–shell type nanoclusters in which the inner atoms of the Pd cluster are substituted by Pt significantly enhance the catalytic activity for cycloocatdiene hydrogenation. In order to discuss the electronic states of core–shell clusters, DFT calculations were carried out for Pd13, Pt13, Pt/Pd12, Pd/Pt12 Pd38 and Pd6/Pt32 clusters. From these calculations, it was found that the charge transfer between the core atoms and the shell atoms played an important role for the modification of the electronic state of the surface atoms in them. [ABSTRACT FROM AUTHOR]

We report a methodology for the ribosomal synthesis of backbone-cyclized peptides involving genetic code reprogramming to introduce one or more nonproteinogenic amino acids. Expression of linear peptides bearing a cysteine-proline dipeptide sequence followed by glycolic acid results in self-rearrangement to a C-terminal diketopiperadine-thioester, which non-enzymatically generates a cyclized peptide. We demonstrate the ribosomal synthesis of several naturally occurring backbone-cyclized peptides and a library based on a bicyclic scaffold, and we identify bioactive sequences by screening and deconvolution. [ABSTRACT FROM AUTHOR]