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Biogenic Mn oxides are reactive and ubiquitous in many Earth surface environments, yet their role in radionuclide sequestration at U mill-tailings sites still require an improved understanding at the nano- and molecular-scales. This study concerns the uptake of Ba, utilized as a safe and chemically appropriate surrogate for radioactive Ra, by biogenic Mn oxides produced by a fungal species, Coprinopsis urticicola, isolated from the mine water of the Ningyo-toge U mine, Okayama, Japan. The biogenic Mn oxides were identified as birnessite nanocrystals O binding to the newly overlying MnO6 layer during coprecipitation. Static desorption experiments for 7 days reveal that the steady-state release rate of adsorbed Ba is ∼1.4 times faster than that of the coprecipitated Ba, when the Ba concentration in the initial loading solution was ∼10–8 mol/L, indicating that the release of intercalated (coprecipitation) Ba to solution is retarded. The present study demonstrates the importance of fungus-generated Mn oxides as an efficient absorber of Ba2+, and likely Ra2+, among soil compounds in U mill-tailings. This may be applicable to other contaminated sites due to the ubiquitous occurrence of fungi in the environment.

Background Although cardiac resynchronization therapy (CRT) provided functional and clinical improvement in patients with heart failure (HF) and electrical intraventricular conduction disturbances, some patients had re-worsening left ventricular (LV) function after a favorable CRT response. We analyzed the clinical variables and cardiac outcomes associated with this re-worsening LV function after CRT. Methods In this study, 71 patients with CRT response who received CRT between 2006 and 2017 were included. CRT response was defined as a “≥ 10% improvement in LV ejection fraction (LVEF) on follow-up.” Patients were classified into two groups: (i) persistent: (n = 48, 68%), defined as those with a CRT response and (ii) re-worsening: (n = 23, 32%), consisting of those who fell out of the definition of a CRT response after an initial CRT response. Results Half of the patients in the re-worsening group failed to maintain a CRT response from two years upwards. A longer duration from HF diagnosis to CRT implantation, nonspecific intraventricular conduction delay (NIVCD) on electrocardiogram at CRT implantation, and a lower increased LVEF at initial CRT response were independent predictors for the re-worsening group. Patients in the re-worsening group had a higher incidence rate for HF hospitalization and cardiac deaths, compared with those in the persistent group. Conclusion One-third of CRT responders experienced re-worsening LVEF, which was associated with poor outcomes. CRT responders with NIVCD, longer HF duration, and a lower increased LVEF at initial CRT response should be monitored with caution.

Clinical predictors for successful weaning of patients from Impella heart pump have not been clarified. We aimed to elucidate the relationship between pulmonary artery catheter (PAC) parameters at the time of Impella weaning and subsequent outcomes.We enrolled consecutive patients who had received Impella for cardiogenic shock. PAC data were collected immediately before Impella weaning. Patients were classified as non-survivors if they died or required any mechanical circulatory support reintroduction within 30 days of weaning.Of 81 patients enrolled, 61 underwent Impella weaning. Of these, 16 were non-survivors. Predictive indicators of non-survival were high pulmonary artery wedge pressure (PAWP; hazard ratio [HR] per 5 mm Hg 1.97, 95% CI 1.35-2.80; p 0.001), high mean pulmonary artery pressure (MPAP; HR per 5 mm Hg 1.90, 1.38-2.58; p 0.001), and low cardiac power output (CPO; HR per 0.1 Watts 0.71, 0.52-0.92; p = 0.006). Cutoff values of PAWP 20 mm Hg, MPAP 22 mm Hg, and CPO 0.59 Watts showed strong associations with 30-day non-survival risk (low risk 8% in patients with low PAWP and high CPO or 4% in patients with low MPAP and high CPO; high risk 100% in patients with high PAWP and low CPO or 82% in patients with high MPAP and low CPO).PAWP or MPAP higher than the cutoff with CPO below the cutoff at Impella weaning were associated with worse outcomes. We proposed a risk classification model for successful Impella weaning using PAC.

Native T1 mapping is used to assess myocardial tissue characteristics without gadolinium contrast agents. The focal T1 high-intensity region can indicate myocardial alterations. This study aimed to identify the association between the native T1 mapping including the native T1 high region and left ventricular ejection fraction (LVEF) recovery in patients with dilated cardiomyopathy (DCM). Patients with newly diagnosed DCM (LVEF of 5 SD in the remote myocardium. Recovered EF was defined as a follow-up LVEF of ≥ 45% and an LVEF increase of ≥ 10% after 2 years from baseline. Seventy-one patients met the inclusion criteria for this study. Forty-four patients (61.9%) achieved recovered EF. Logistic regression analysis showed that the native T1 value (OR: 0.98; 95% CI: 0.96–0.99; P = 0.014) and the native T1 high region (OR: 0.17; 95% CI: 0.05–0.55; P = 0.002), but not late gadolinium enhancement, were independent predictors of recovered EF. Compared with native T1 value alone, combined native T1 high region and native T1 value improved the area under the curve from 0.703 to 0.788 for predicting recovered EF. Myocardial damage, which was quantified using native T1 mapping and the native T1 high region were independently associated with recovered EF in patients with newly diagnosed DCM.

Biogenic manganese (Mn) oxides occur ubiquitously in the environment including the uranium (U) mill tailings at the Ningyo-toge U mine in Okayama, Japan, being important in the sequestration of radioactive radium. To understand the nanoscale processes in Mn oxides formation at the U mill tailings site, Mn

Background Prediction of atrioventricular block (AVB) resolution after steroid therapy in patients with cardiac sarcoidosis (CS) is difficult. Methods We identified 24 patients with CS and complete or advanced AVB receiving steroid therapy. AVB resolution was assessed by reviewing surface electrocardiogram and the percentage of ventricular pacing required on subsequent device interrogation reports. Results AVB resolution was noted in eight (33%) patients 1 year after receiving steroid therapy. Univariate Cox regression analysis demonstrated that left ventricular ejection fraction (LVEF) (hazard ratio [HR] 1.07, 95% confidence interval [CI] 1.01‐1.14, P = .016), interval from recognized AVB to start of steroid therapy (HR 0.98, 95% CI 0.95‐0.99, P, Resolution of AVB was observed in 33% patients with CS and AVB after steroid therapy. Univariate analysis demonstrated that a shorter interval from recognition of AVB to start of steroid therapy, higher LVEF, higher lysozyme levels were significantly associated with resolution of AVB after steroid therapy. The combination of each variable associated with resolution of AVB could be able to distinguish patients with resolution of AVB from those without.

Ferrihydrite, a hydrous ferric oxide, is ubiquitous in silica-rich mine drainage sites, although some uncertaity remains concerning its nanoscale texture and colloidal properties such as its association with amorphous silica and reactions with contaminant metals. To understand the mechanisms of natural attenuation of contaminants governed by ferrihydrite and amorphous silica aggregations, mine tailings material from the Ningyo-toge uranium deposit, Japan, has been investigated in detail utilizing many traditional solution and mass spectroscopy methods, as well as synchrotron-based methods the latest in FIB- and analytic TEM-based technologies. At this site, the past mining activity results in slightly acidic mine drainage and the contamination of a mill tailings pond with relatively high concentrations of toxic elements, including U, As, and Ra. We have systematically investigated the geochemistry of water, colloids, and sediments from the groundwater draining the former mine site (now remediated), down gradient to the mill tailings pond where the water pH remains ∼6.2. Groundwater with 0.18 mg/L dissolved oxygen (DO) is oxygenated rapidly to levels of 1.65 mg/L DO when exposed to the atmosphere along this flow path. Dissolved Fe2+ is oxidized instantly to form ferrihydrite nanoparticle aggregates > 200 nm in diameter, adsorbing ∼67% of the total As (3.36 µmol/L) in solution. For solutions and particles/aggregates passing through 200-nm filters, ∼17% of the 1.17 µmol/L As is sorbed on these smaller ferrihydrite aggregates. Simultaneously, varying amounts of amorphous silica with particle sizes as small as several nanometers were observed to adsorb onto ferrihydrite aggregates. Arsenic is present predominantly as arsenate, As(V), and preferentially adsorbs to ferrihydrite within these ferrihydrite–amorphous silica aggregates. Arsenate adsorption is not inhibited by silica adsoption on ferrihydrite when the Si/Fe composition is ∼0.25. Uranium is also adsorbed onto aggregates of colloids. After 24 h of static exposure to the ambient atmosphere, the zeta potential of the aggregate that formed in oxygenated water decreases from −16 to −24 mV, near the zeta potential of pure silica, potentially leading to increased colloidal stability. Some large-sized aggregates are deposited at the bottom of the collecting well and slowly adsorb minor amounts of Mn (1.45 wt.%); other aggregates are transported to the mill tailings pond downsteam, where the water is further oxidized (DO = 3.09 mg/L), and deposited onto the sediment together with birnessite, a hydrated Mn-oxide that appears to be biogenic in this case. During sedimentation, associations of amorphous silica within the aggregate play a key role in retaining the ferrihydrite structure that adsorbs toxic elements such as As. Consequently, the mechanism of natural attenuation at the nanoscale constrained by the chemical and physical properties of ferrihydrite–amorphous silica aggregates is of critical importance in the Ningyo-toge mill tailing site. It is shown that it is also important in other mine drainage and mill tailings sites due to the ubiquitous and dominant occurrence of both Si and Fe in these types of settings.

Combination therapy with venoarterial extracorporeal membrane oxygenation (VA-ECMO) and Impella (ECPELLA) has been known to be a favorable strategy of mechanical circulation support for patients with fatal cardiogenic shock. However, the practical strategy for weaning ECPELLA in patients with right ventricular (RV) dysfunction remains unclear. We describe a case of a 63-year-old male with fulminant myocarditis presenting with cardiogenic shock who required ECPELLA to improve hemodynamics. Because of persistent severe RV dysfunction despite the introduction of intravenous dobutamine and milrinone, VA-ECMO could not be weaned. Inhaled nitric oxide (iNO) was introduced at 20 ppm to reduce RV afterload, resulting in increased cardiac output (from 1.6 to 5.5 L/min) and ameliorated RV performance (the pulmonary artery pulsatility index was from 0.47 to 1.11). Subsequently, VA-ECMO could be weaned. iNO, a selective pulmonary vasodilator, reduces pulmonary vascular resistance, resulting in reduced RV afterload. This is the first case of iNO usage for the management of cardiogenic shock supported by ECPELLA. iNO could be a favorable strategy in ECPELLA patients with refractory RV dysfunction for weaning VA-ECMO through bridging to recovery. LEARNING OBJECTIVE: The practical strategy for weaning venoarterial extracorporeal membrane oxygenation and Impella (ECPELLA) in patients with concomitant right ventricular dysfunction remains unclear. Inhaled nitric oxygen is a novel weaning strategy for patients with biventricular dysfunction supported by ECPELLA. If the response of inhaled nitric oxygen was insufficient under ECPELLA support, implantable ventricular assist devices or transplantation should be considered.

Clinical parameters with correlation to diuretic effects after initiation of sodium-glucose cotransporter-2 (SGLT2) inhibitors are unclear. We aimed to identify the factors associated with the diuretic effect observed following the initiation of SGLT2 inhibitors in patients with diabetes having an acute heart failure (HF). Fifty-six patients included were hospitalized for acute HF with diabetes and started on SGLT2 inhibitors. Changes in urine volume (ΔUV) and blood/urine laboratory parameters before and during the first 4 days of therapy were evaluated. Data were prospectively obtained under clinically stable conditions after initial HF treatment. UV increased following the initiation of SGLT2 inhibitors [UV at baseline (BL): 1383 ± 479 mL/day; ΔUV over 4 days: + 189 ± 358 mL/day]. Multivariate analysis revealed no association between BL-hemoglobin A1c or BL-estimated glomerular filtration rate and ΔUV. Conversely, higher BL-fasting plasma glucose (FPG) and higher BL-urine N-acetyl-β-D-glucosaminidase (NAG) were associated with a higher ΔUV. ΔUV was inversely associated with ΔFPG and ΔNAG, and positively associated with Δurinary sodium excretion. Elevated FPG and NAG both improved over 4 days of treatment. In conclusion, the diuretic effect of SGLT2 inhibitors was glycemia-dependent, and was associated with a reduction in elevated renal-tubular markers in hospitalized HF complicated with diabetes.

Background Clinical significance of left atrial (LA) function and geometry in patients with dilated cardiomyopathy (DCM) remains uncertain. Hypothesis LA geometric parameters assessed by cardiac magnetic resonance (CMR) predict the prognosis in patients with DCM. Methods The present study included patients with DCM and sinus rhythm who underwent CMR between December 2007 and April 2018. LA volume was measured using CMR. LA sphericity index was computed as the ratio of the measured maximum LA volume by the volume of a sphere with maximum LA length diameter. Results We included 255 patients in this study. During the mean follow‐up of 3.92 years, hospitalization for HF occurred in 37 patients. The LA sphericity index was significantly higher in patients with hospitalization for HF than in those without (0.78 ± 0.35 vs. 0.58 ± 0.18, p

Background: Left ventricular reverse remodeling by cardiac resynchronization therapy (CRT) can significantly improve the prognosis for heart failure (HF) patients. The time course of CRT response remains poorly characterized. Method and Results: This retrospective study included 99 HF patients who received a CRT device at a single center from 2006 to 2017. CRT response was defined as ≥10% improvement in left ventricular ejection fraction on follow-up. They were divided into three groups: early responders (ERs): 49 patients with CRT response by the six-month follow-up; late responders (LRs): 17 patients with CRT response between six-month and three-years; and non-responders (NRs): 33 patients with no CRT response. The ERs and LRs had significantly lower rates of HF hospitalization and all-cause deaths than the NRs. Multivariate logistic regression analysis identified that narrower QRS duration before implantation (p = 0.046) and the presence of moderate to severe mitral regurgitation (MR) at the six-month follow-up (p = 0.035) as independent predictors of NRs. Conclusions: Regardless of the timing, HF patients who have CRT response have a better long-term prognosis than NRs. The Severity of MR can predict whether a patient with no response at the six-month follow-up will be NRs.

Aims Intestinal oedema is one of the manifestations associated with right‐sided heart failure (HF), which is known to be associated with poorer patient outcomes. We attempted to reveal the association between intestinal oedema and diuretic resistance in hospitalized patients with acute HF. Methods and results Among 213 hospitalized patients with acute HF, abdominal ultrasonography was performed under clinically stable conditions after initial HF treatments. The association among abdominal ultrasonographic parameters, maintenance doses of loop diuretics, and responsiveness to initial loop diuretic treatment was evaluated. Higher mean colon wall thickness (CWT) independently correlated with a higher dose of loop diuretics at enrolment (adjusted β = 0.198, P = 0.0004). Increased mean CWT also correlated with poor response to oral loop diuretics as an initial treatment, whereas it did not correlate with the response to intravenous loop diuretics. Discrimination of non‐responders to initial oral loop diuretics resulted in a sensitivity of 0.772 and a specificity of 0.733 using a mean CWT cut‐off value of ≥3 mm. Conclusions In hospitalized patients with acute HF, a strong correlation was identified among the severity of intestinal oedema, required quantities as maintenance loop diuretic doses, and poor responsiveness to oral loop diuretics at admission.

Background Re-worsening left ventricular ejection fraction (LVEF) after initial recovery occurs in some patients with dilated cardiomyopathy (DCM). However, prevalence and predictors of re-worsening LVEF in longitudinal follow-up are unclear. Late gadolinium enhancement of cardiovascular magnetic resonance (LGE-CMR) can evaluate the damage of myocardial tissue. Purpose This study sought to evaluate the clinical parameters including LGE-CMR to predict re-worsening LVEF in patients with recent-onset DCM. Methods We included patients with recent-onset DCM who had an LVEF 5% LVEF from baseline and had an LVEF≥45% after medical therapy. Patients were divided into three groups: (1) Improved: defined as those with sustained LVEF ≥45% after initial LVEF recovery; (2) Re-worse: those with decreased >5% and had an LVEF Results Of 138 patents, 82 patients (59%) were the Improved group, 42 patients (30%) were the Re-worse group, and 14 (10%) were the Not-improved group. Loess curves of long-term LVEF trajectories showed that LVEF in the Re-worse group increased first 2 years and declined slowly thereafter (Fig. 1A). Re-worsening LVEF occurred 4.5±2.2 years after initial LVEF recovery. Multivariate logistic regression analysis demonstrated that LGE area at baseline (Odds ratio: 1.09, 95% confidence interval (CI) 1.02–1.18, p=0.014) and Log brain natriuretic peptide (BNP) at initial LVEF recovery (Odds ratio: 1.53, 95% confidence interval (CI) 1.01–2.31, p=0.042) were independent predictors for Re-worsening LVEF. Kaplan Meier analysis demonstrated that the risk of cardiac events in the Re-worse group was significantly higher (hazard ratio: 3.93, 95% CI 1.49–10.36, p=0.006) than in the Improved group and lower risk than in the Not-improved group (hazard ratio: 0.28, 95% CI 0.12–0.62, p=0.002) (Fig. 1B). Conclusion Re-worsening LVEF occurred in 30% of patients in patients with recent-onset DCM. LGE area and BNP at initial LVEF recovery were independently associated with re-worsening LVEF after initial LVEF recovery. Figure 1 Funding Acknowledgement Type of funding source: None

Background Left atrial (LA) enlargement is associated with cardiac events in patients with dilated cardiomyopathy (DCM). However, the clinical significance of LA function and geometry in patients with DCM remains uncertain. Cardiac magnetic resonance (CMR) is the current gold standard modality to assess LA function and geometry. Purpose The aim of the present study was to investigate the clinical significance of LA parameters assessed by CMR in patients with DCM. Methods The present study included patients with DCM and sinus rhythm who underwent CMR between December 2007 and April 2018. LA volume was measured using CMR. LA empty fraction was calculated according to LA volume differences. The LA sphericity index was computed as the ratio of the measured LA maximum volume to the volume of a sphere with maximum LA length diameter (Figure 1A). We investigated the relationship between LA parameters measured by CMR and hospitalization for heart failure (HF). Results We included 255 patients in this study. During the mean follow-up of 3.66 [1.85–6.25] years, hospitalization for HF occurred in 37 patients (14.5%). Although there were no significant differences in LA volume and LA empty fraction between patients with HF hospitalization and those without, LA sphericity index was significantly higher in patients with HF hospitalization than in those without (0.78±0.35 vs. 0.58±0.18, P Conclusions LA sphericity index was an independent predictor of hospitalization for HF. Assessment of LA geometric parameter including LA sphericity might be useful for risk stratification toward worsening HF in patients with DCM. Figure 1 Funding Acknowledgement Type of funding source: None

Plutonium association and transport by ferrihydrite has been confirmed in the groundwater system of Lake Karachai at the Mayak Production Association, Russia (Novikov et al. 2006). Since this initial description, there has been substantial progress in understanding the mechanisms that control the concentrations and distribution of Pu at the Mayak site. This chapter is a concise review of work during the past 10 years that utilizes to advantage recent advances in nanoscale, analytical techniques. The structure of ferrihydrite (P63mc) was determined using a pair-distribution function analysis. Scanning transmission electron microscopy of Mayak colloids resolved the occurrence of mixed silica nano-colloids and ferrihydrite. Thermodynamic properties for aqueous Pu-species have been updated. Inner-sphere surface complexation was determined for adsorbed Pu using synchrotron-based X-ray absorption spectroscopy. The adsorbed Pu can transform into Pu-dioxide nanoparticles as revealed by high-resolution transmission electron microscopy. Plutonium polymerization can also proceed by aggregation of cubic Pu-dihydroxy building blocks of Pu(OH)22+•6H2O. Plutonium desorption occurs associated with re-adsorption at neutral pH. To establish comprehensive model of Pu transport at the Mayak site, the detailed mechanisms described above must be considered. Rigorous characterization of colloids is necessary and these results must be compared with results obtained from experimental studies. The state-of-the-art knowledge on the Pu association with Fe hydroxides is now well enough understood that safety assessments no longer need to rely on the classical Kd approach.

Background Normalization of left ventricular (LV) contraction is a strong surrogate marker of favorable prognosis in patients with dilated cardiomyopathy (DCM). Although several studies have reported the individual predictive significance of clinical and imaging parameters for LV recovery in patients with DCM, there have been no reports on the scoring systems that combine these multifactorial parameters. Methods and results In 406 idiopathic patients with DCM, there were 185 (46%) with LV recovery at 1-year follow-up after pharmacotherapy, which was defined as improvements in LV ejection fraction of ≥+10% together with absolute values of ≥50%. Multivariate analysis demonstrated that eight baseline clinical factors and the absence of late gadolinium enhancement (negative LGE) on magnetic resonance imaging were independently associated with LV recovery. The highest odds ratio for the prediction of LV recovery was negative LGE (odds ratio: 5.62, 95% confidence interval: 2.97–10.6; p Conclusion Combined assessment using clinical and imaging parameters has a high prognostic value for predicting response to pharmacotherapy in patients with DCM.