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Background: Currently, pathophysiological mechanisms of post‐acute sequelae of coronavirus disease‐19‐cardiovascular syndrome (PASC‐CVS) remain unknown. Methods and results: Patients with PASC‐CVS exhibited significantly higher circulating levels of severe acute respiratory syndrome‐coronavirus‐2 spike protein S1 than the non‐PASC‐CVS patients and healthy controls. Moreover, individuals with high plasma spike protein S1 concentrations exhibited elevated heart rates and normalized low frequency, suggesting cardiac β‐adrenergic receptor (β‐AR) hyperactivity. Microscale thermophoresis (MST) assay revealed that the spike protein bound to β1‐ and β2‐AR, but not to D1‐dopamine receptor. These interactions were blocked by β1‐ and β2‐AR blockers. Molecular docking and MST assay of β‐AR mutants revealed that the spike protein interacted with the extracellular loop 2 of both β‐ARs. In cardiomyocytes, spike protein dose‐dependently increased the cyclic adenosine monophosphate production with or without epinephrine, indicating its allosteric effects on β‐ARs. Conclusion: Severe acute respiratory syndrome‐coronavirus‐2 spike proteins act as an allosteric β‐AR agonist, leading to cardiac β‐AR hyperactivity, thus contributing to PASC‐CVS. [ABSTRACT FROM AUTHOR]

Vision plays a crucial role in the survival of animals, and the visual system has particularly selectively evolved in response to the visual environment, ecological niche, and species habitats in vertebrate species. To date, a horizontal streak of retinal ganglion cell (RGC) distribution pattern is observed across mammal species. Here, we report that the giant panda's vertically oriented visual streak, combined with current evidence of the animal's forward‐placed eyes, ocular structure, and retinal neural topographic distribution patterns, presents the emergence of a well‐adapted binocular visual system. Our results suggest that the giant panda may use a unique way to processing binocular visual information. Results of mathematical simulation are in favor of this hypothesis. The topographic distribution properties of RGCs reported here could be essential for understanding the visual adaptation and evolution of this living fossil. [ABSTRACT FROM AUTHOR]

Hot forming is an effective approach for improving the formability of ultrathin metal sheets, such as those made of stainless steel and pure titanium. However, the increased friction coefficient between the tool and the high-temperature metal sheet negatively affects material flow during hot forming, potentially resulting in severe local thinning or even cracking. This study explores the frictional behavior of 0.1 mm thick ferritic stainless steel (FSS) and commercially pure titanium (CP-Ti) sheets at elevated temperatures. A friction testing apparatus was developed to measure the friction coefficients of these metal sheets from room temperature (25 °C) up to 600 °C. The friction coefficient of the FSS sheet increased monotonically with temperature, whereas that of the CP-Ti sheet first increased and then decreased. Post-friction testing microscopic examination demonstrated that built-up edges formed on the surfaces of the friction blocks when rubbed against the stainless steel, contributing to the higher friction coefficients. This study provides a foundation for understanding frictional behavior during the hot forming of ultrathin metal sheets. [ABSTRACT FROM AUTHOR]

Aims: Liver fibrosis was associated with adverse outcomes in various cardiovascular diseases. The current risk stratification of non-ischemic dilated cardiomyopathy (NIDCM) still largely depends on the left ventricular ejection fraction (LVEF). At present, the relationship between liver fibrosis and prognosis in patients with NIDCM remains blank. Methods and results: A total of 433 NIDCM patients were analysed in this study. Liver fibrosis was assessed by three liver fibrosis scores (LFS), including aspartate aminotransferase to platelet ratio index (APRI), aspartate aminotransferase/alanine aminotransferase ratio (AST/ALT ratio), and gamma-glutamyltransferase to platelet ratio (GPR). The primary endpoint was defined as all-cause mortality or heart transplantation (ACM/HTx). During a median follow-up period of 1.7 years, 140 ACM/HTx events occurred. Positive associations were observed between LFS and ACM/HTx. Patients with elevated APRI, AST/ALT ratio, and GPR scores exhibited increased ACM/HTx (all P < 0.05). Intermediate-to-high APRI [hazard ratio (HR) 1.66, 95%CI 1.06–2.61, P = 0.027], AST/ALT ratio (HR 1.59, 95%CI 1.07–2.36, P = 0.021), and GPR (HR 1.64, 95%CI 1.11–2.42, P = 0.013) were independently associated with increased risk of ACM/HTx, even after adjusting for LVEF and other covariates. The positive relationship remains consistent across different subgroups, including those with diabetes and obesity. Conclusions: Elevated liver fibrosis scores were associated with a worse outcome beyond LVEF in patients with NIDCM, which may provide additional prognostic value in the management of NIDCM. [ABSTRACT FROM AUTHOR]

Magnetosonic (MS) wave is one of the most common electromagnetic emissions in the magnetosphere, while quasi‐electrostatic magnetosonic (QEMS) waves are seldom observed. Here we present an interesting QEMS event detected by Van Allen Probe A on 9 January 2014, in which the presence of multi‐band QEMS emissions shows evident correlations with relatively low plasma densities (∼10 cm−3) and enhancements of suprathermal (∼10 − 100 eV) proton fluxes. Based on the observed proton distributions, simulations demonstrate very similar profiles to the observed QEMS in the wave spectral characteristics. Parametric studies indicate that the QEMS growth rate can increase by ∼20 times with the plasma density decreasing from 50 to 10 cm−3. Effective growth rates of higher‐band QEMS occur when the suprathermal proton population is sufficiently large. This study reveals that low densities and large suprathermal proton populations are favorable for generating distinct multi‐band QEMS in the magnetosphere. Plain Language Summary: Magnetosonic (MS) wave is one of the most common electromagnetic emissions in the magnetosphere, while quasi‐electrostatic magnetosonic (QEMS) wave is seldom observed. Here we report an interesting event detected by Van Allen Probe A on 9 January 2014, in which multi‐band QEMS emissions occurred exactly corresponding to the presence of low plasma densities (∼10 cm−3) and enhancements of suprathermal (∼10 − 100 eV) proton fluxes. Based on the observed data of three typical time intervals, we perform simulations to investigate how the plasma density and suprathermal protons affect the generation of QEMS. Our results are quite comparable with the observations in the patterns of wave intensity and frequency characteristics. We then adjust the parameters and find that QEMS growth rate increases by ∼20 times with the plasma density decreasing from 50 to 10 cm−3. Effective growth rates of higher‐band QEMS only occur when the suprathermal proton population is ≥0.75 cm−3. These results demonstrate that the low plasma density is propitious for generating distinct QEMS, and a sufficiently large suprathermal proton population is beneficial for forming the multi‐band structure of QEMS. Key Points: Multi‐band quasi‐electrostatic magnetosonic (QEMS) was observed exactly corresponding to low plasma densities and enhanced suprathermal proton fluxesSimulations indicate that QEMS growth rate can increase by about 20 times with the plasma density decreasing from 50 to 10 cm−3A large suprathermal (∼10–100 eV) proton population is favorable for extending the QEMS to higher bands [ABSTRACT FROM AUTHOR]

Aims: Recent studies suggested that both left ventricular ejection fraction (LVEF) lower than 60% or higher than 65% were associated with an increased mortality in the general population. Uncertainty remains regarding adverse outcomes across LVEF in coronary artery disease (CAD). The common understanding was that LVEF <40% was associated with an increased risk of mortality. But the threshold at LVEF of 40% was arbitrary because quite a lot of adverse outcomes existed in patients with ejection fraction >40%. We aimed to evaluate the relationship between LVEF and mortality or adverse events in CAD patients undergoing percutaneous coronary intervention (PCI). Methods and results: A total of 10 252 CAD patients undergoing PCI from an observational cohort were studied. All‐cause mortality and major adverse cardiovascular and cerebrovascular events (MACCE) were set as outcomes. Kaplan–Meier curves, adjusted Cox regression models, and restricted cubic spline analyses were used for evaluation. A total of 137 (1.3%) patients had all‐cause mortality, and 816 (8.0%) patients had MACCE during a median of 2.4 years of follow‐up. The median LVEF was 64%. All‐cause mortality and MACCE rates changed substantially across LVEF categories, and a linear inverse relationship of LVEF with all‐cause mortality and MACCE risk was observed. All‐cause mortality or MACCE risk increased significantly below an LVEF of 55 or 65%, respectively. Patients with LVEF <55% had a more than 3.5‐fold higher mortality than those with LVEF ≥55%. Patients with LVEF <65% had a more than 1.3‐fold higher MACCE than those with LVEF ≥65%. Below 55 or 65%, there was a rise in mortality or MACCE. A gradient–response relationship was observed, with an all‐cause mortality risk range between 8.6‐fold and 3.0‐fold increase from LVEF <40 to 50–54.9% and MACCE risk range between 2.4‐fold and 1.4‐fold from LVEF <40 to 60–64.9%. Conclusions: In CAD patients undergoing PCI, LVEF lower than 55% or LVEF lower than 65% was correlated with increased all‐cause mortality and MACCE respectively, whereas higher LVEF was not. [ABSTRACT FROM AUTHOR]

Limited studies have focused on the impact of high-sensitivity C-reactive protein (hsCRP) to albumin ratio (CAR) on cardiovascular outcomes in patients undergoing percutaneous coronary intervention (PCI). Hence, the present study evaluates the association between CAR and cardiovascular outcomes in patients undergoing drug-eluting stent (DES) implantation. We consecutively enrolled 9375 CHD patients undergoing DES implantation. All patients were divided into 3 groups according to their CAR: tertile 1 (CAR ≤.02, n=3125), tertile 2 (.02.06, n = 3125). The primary endpoint was major adverse cardiovascular and cerebrovascular events (MACCE). Kaplan-Meier analysis indicated that the incidences of MACCE and MI increased with high tertiles of the CAR (MACCE: 8.7 vs 10.5 vs 12.3%, log-rank P <.001; MI: 3.3 vs 4.0 vs 4.7%, long-rank P =.015). Cox regression analysis suggested that CAR was an independent risk factors for MACCE (HR per standard deviation (SD) increase: 1.07, 95% CI, 1.01–1.14, P =.024), and MI (HR per SD increase: 1.11, 95% CI, 1.01–1.22, P =.028). In conclusion, the CAR is an independent predictor of MACCE and MI in CHD patients. [ABSTRACT FROM AUTHOR]

A tertiary amine-catalyzed asymmetric [3+2] spiroannulation reaction of pyrazolone-derived Morita–Baylis–Hillman carbonates with alkynyl ketones was achieved under mild conditions. This protocol offers a facile approach to chiral spiro[cyclopentadiene-pyrazolone] scaffolds in good to high yields (up to 92%) with good degrees of enantiocontrol (up to 98% ee). In addition, scale-up reaction and transformation of the products were performed to show the synthetic utility of this protocol. [ABSTRACT FROM AUTHOR]

Background: Acute pancreatitis is a sudden inflammation of the pancreas. Although interleukin‐23 (IL‐23) is associated with the severity of acute pancreatitis, the underlying mechanism remains largely unknown. Herein, its regulatory mechanisms were explored in this study. Methods: RNA‐sequencing analysis selected the differently expressed genes in cerulean‐induced acute pancreatitis mice. Polymerase chain reaction analysis determined IL‐23 expression in cyclin‐dependent kinase 2 (Cdk2) short hairpin RNA (shRNA)‐pretreated or DDB1–cullin‐4‐associated factor‐2 (DCAF2)‐overexpressed RAW264.7 cells or CDKs inhibitor AT7519/cullin ring‐finger ubiquitin ligase inhibitor MLN4924‐treated bone marrow‐derived macrophages in the presence of lipopolysaccharides (LPS). Pancreatic damages were evaluated in AT7519‐treated pancreatitis mice. Results: Pancreatitis mice displayed an increased expression on IL‐23 and a decreased expression of Cdk2. Inhibiting Cdk2 by shRNA or AT7519 significantly induced IL‐23 expression in LPS‐treated RAW cells. Moreover, AT7519 treatment significantly aggravated the severity of acute pancreatitis in mice. Furthermore, AT7519 remarkably increased DCAF2 expression, which was also induced by MLN4924 no matter with or without AT7519 in vitro. On the contrary, overexpressing DCAF2 blocked the stimulatory effect of AT7519 on IL‐23 expression. Conclusion: Cdk2 negatively regulates IL‐23 expression by inhibiting DCAF2 in acute pancreatitis, indicating that Cdk2 might serve as a promising therapeutic target for acute pancreatitis. [ABSTRACT FROM AUTHOR]