Volume markers in left ventricular diastolic dysfunction and adverse outcomes in peritoneal dialysis patients: a prospective cohort study.

Left ventricular diastolic dysfunction (LVDD) is an early event associated with cardiovascular complications and poor prognosis in chronic kidney disease patients undergoing dialysis. In this study, we investigated whether diastolic dysfunction, measured by the E/E' ratio, affects adverse outcomes in peritoneal dialysis (PD) patients (n = 148). Our results showed that patients with an E/E' ratio ≥ 15 were more likely to be female, have a longer dialysis vintage, have significantly higher left atrial volume index and left atrial kinetic energy levels, have lower E' levels and LV hypertrophy (LVH) degree, and have higher volume markers. Kaplan-Meier curves revealed that patients with a higher E/E' ratio had worse survival and a higher risk of heart failure than those with a lower E/E' ratio. Subgroup analysis demonstrated that non-diabetic patients with a higher E/E' ratio had a higher risk of heart failure than those with a lower E/E' ratio. Cox proportional hazard regression analysis indicated that the ECW/ICW ratio was strongly associated with LVDD and confirmed that the E/E' ratio was an independent risk factor for overall death. Our study suggests that monitoring the E/E' ratio in PD patients is important for improving their prognosis.

Management strategies and outcomes of acute coronary syndrome (ACS) during Covid-19 pandemic.

BACKGROUND: The COVID-19 outbreak represents a significant challenge to international health. Several studies have reported a substantial decrease in the number of patients attending emergency departments with acute coronary syndromes (ACS) and there has been a concomitant rise in early mortality or complications during the COVID-19 pandemic. A modified management system that emphasizes nearby treatment, safety, and protection, alongside a closer and more effective multiple discipline collaborative team was developed by our Chest Pain Center at an early stage of the pandemic. It was therefore necessary to evaluate whether the newly adopted management strategies improved the clinical outcomes of ACS patients in the early stages of the COVID-19 pandemic. METHODS: Patients admitted to our Chest Pain Center from January 25th to April 30th, 2020 based on electronic data in the hospitals ACS registry, were included in the COVID-19 group. Patients admitted during the same period (25 January to 30 April) in 2019 were included in the pre-COVID-19 group. The characteristics and clinical outcomes of the ACS patients in the COVID-19 period group were compared with those of the ACS patients in the pre-COVID-19 group. Multivariate logistic regression analyses were used to identify the risk factors associated with clinical outcomes. RESULTS: The number of patients presenting to the Chest Pain Center was reduced by 45% (p = 0.01) in the COVID-19 group, a total of 223 ACS patients were included in the analysis. There was a longer average delay from the onset of symptom to first medical contact (FMC) (1176.9 min vs. 625.2 min, p = 0.001) in the COVID-19 period group compared to the pre-COVID-19 group. Moreover, immediate percutaneous coronary intervention (PCI) (80.1% vs. 92.3%, p = 0.008) was performed less frequently on ACS patients in the COVID-19 group compared to the pre-COVID-19 group. However, more ACS patients received thrombolytic therapy (5.8% vs. 0.6%, p = 0.0052) in the COVID-19 group than observed in the pre-COVID-19 group. Interestingly, clinical outcome did not worsen in the COVID-19 group when cardiogenic shock, sustained ventricular tachycardia, ventricular fibrillation or use of mechanical circulatory support (MCS) were compared against the pre-COVID-19 group (13.5% vs. 11.6%, p = 0.55). Only age was independently associated with composite clinical outcomes (HR = 1.3; 95% CI 1.12-1.50, p = 0.003). CONCLUSION: This retrospective study showed that the adverse outcomes were not different during the COVID-19 pandemic compared to historical control data, suggesting that newly adopted management strategies might provide optimal care for ACS patients. Larger sample sizes and longer follow-up periods on this issue are needed in the future.

Structure-Guided Designing Pre-Organization in Bivalent Aptamers.

Multivalent interaction is often used in molecular design and leads to engineered multivalent ligands with increased binding avidities toward target molecules. The resulting binding avidity relies critically on the rigid scaffold that joins multiple ligands as the scaffold controls the relative spatial positions and orientations toward target molecules. Currently, no general design rules exist to construct a simple and rigid DNA scaffold for properly joining multiple ligands. Herein, we report a crystal structure-guided strategy for the rational design of a rigid bivalent aptamer with precise control over spatial separation and orientation. Such a pre-organization allows the two aptamer moieties simultaneously to bind to the target protein at their native conformations. The bivalent aptamer binding has been extensively characterized, and an enhanced binding has been clearly observed. This strategy, we believe, could potentially be generally applicable to design multivalent aptamers.