Estrogen-dependent enhancement of NO production in the nucleus tractus solitarius contributes to ethanol-induced hypotension in conscious female rats

Background- Our previous pharmacological and cellular studies showed that peripheral (cardiac and vascular) NOS-derived NO is implicated in the estrogen-dependent hypotensive action of ethanol in female rats. The objective of this study was to test the hypothesis that enhanced NO production in the nucleus tractus solitarius (NTS) is implicated in the estrogen-dependent hypotensive action of ethanol. Methods- To achieve this goal, we utilized in vivo electrochemistry to measure real time changes in neuronal NO to investigate the acute effects of intragastric ethanol (0, 0.5 or 1 g/kg) on NO in NTS neurons, blood pressure (BP) and heart rate (HR) in conscious female rats in the absence (ovariectomized, OVX, rats) or presence of estrogen. Results- In sham operated (SO) rats, ethanol elicited dose-related increase in NTS NO and reduction in BP. These neurochemical and blood pressure effects of ethanol were absent in OVX rats. Whether the neurochemical effect of ethanol and the associated hypotension are dependent on rapid estrogen signaling was investigated. In OVX rats pretreated, 30 min earlier, with estrogen (E2, ug/kg), intragastric ethanol (1 g/kg) increased NTS NO and reduced BP and these responses were comparable to those obtained in SO rats. Conclusions- The present findings suggest that increased production of NO in NTS neurons contributes to ethanol-evoked hypotension in female rats. Further, ethanol enhancement of neuronal NO production in the brainstem is dependent on rapid estrogen signaling. Originally published Alcohol: Clinical and Experimental Research, Vol. 33, No. 2, Feb 200

Estrogen-dependent enhancement of NO production in the nucleus tractus solitarius contributes to ethanol-induced hypotension in conscious female rats

Background- Our previous pharmacological and cellular studies showed that peripheral (cardiac and vascular) NOS-derived NO is implicated in the estrogen-dependent hypotensive action of ethanol in female rats. The objective of this study was to test the hypothesis that enhanced NO production in the nucleus tractus solitarius (NTS) is implicated in the estrogen-dependent hypotensive action of ethanol. Methods- To achieve this goal we utilized in vivo electrochemistry to measure real time changes in neuronal NO to investigate the acute effects of intragastric ethanol (0 0.5 or 1 g/kg) on NO in NTS neurons blood pressure (BP) and heart rate (HR) in conscious female rats in the absence (ovariectomized OVX rats) or presence of estrogen. Results- In sham operated (SO) rats ethanol elicited dose-related increase in NTS NO and reduction in BP. These neurochemical and blood pressure effects of ethanol were absent in OVX rats. Whether the neurochemical effect of ethanol and the associated hypotension are dependent on rapid estrogen signaling was investigated. In OVX rats pretreated 30 min earlier with estrogen (E2 ug/kg) intragastric ethanol (1 g/kg) increased NTS NO and reduced BP and these responses were comparable to those obtained in SO rats. Conclusions- The present findings suggest that increased production of NO in NTS neurons contributes to ethanol-evoked hypotension in female rats. Further ethanol enhancement of neuronal NO production in the brainstem is dependent on rapid estrogen signaling. Originally published Alcohol: Clinical and Experimental Research Vol. 33 No. 2 Feb 200

Thermoresponsive Graphene Membranes with Reversible Gating Regularity for Smart Fluid Control

Precisely regulating water and molecule permeation through membranes is of crucial significance in broad domains such as water filtration and smart reactors. Comparing with routine stiff membranes, stimuli‐response polymers endow porous membranes with various gating properties, but most of these membranes have only one‐way gating performance, that is, either positive or negative. Here poly(N‐isopropylacrylamide) (PNIPAM) grafted graphene oxide (GO) membranes with reversible positive/negative gating regularity are constructed by simply tuning the molecule grafting density. The water and small molecule permeance of the membranes can be regulated by adjusting environment temperature. Based on this tunable thermoresponsive gating regularity, a bidirectional fluidic controlling system is designed by integrating a positive membrane and a negative membrane, which can be employed as a self‐adaptive gating reactor. This strategy provides an insight into constructing smart gating membranes with extraordinary properties, showing promising applications in micro/nanofluidic valves and temperature sensitive biochemical reactors.J.L. and L.-J.Y. contributed equally to this work. The authors acknowledge the National Natural Science Foundation of China (NSFC) (Grant Nos. 21774005, 21433012, 21374001, and 51772010), National Natural Science Foundation for Outstanding Youth Foundation, the Fundamental Research Funds for the Central Universities, the National Program for Support of Top-notch Young Professionals, the 111 project (Grant No. B14009) and the generous allocation of computing time from the National Computational Infrastructure (NCI) National Facility and the system administration support provided by the Faculty of Science at the University of Western Australia (UWA) to the Linux cluster of the Karton group. The authors also thank Prof. Longcheng Gao at Beihang University for helpful revision suggestions

Thermoresponsive Graphene Membranes with Reversible Gating Regularity for Smart Fluid Control

Precisely regulating water and molecule permeation through membranes is of crucial significance in broad domains such as water filtration and smart reactors. Comparing with routine stiff membranes, stimuli-response polymers endow porous membranes with various gating properties, but most of these membranes have only one-way gating performance, that is, either positive or negative. Here poly(N-isopropylacrylamide) (PNIPAM) grafted graphene oxide (GO) membranes with reversible positive/negative gating regularity are constructed by simply tuning the molecule grafting density. The water and small molecule permeance of the membranes can be regulated by adjusting environment temperature. Based on this tunable thermoresponsive gating regularity, a bidirectional fluidic controlling system is designed by integrating a positive membrane and a negative membrane, which can be employed as a self-adaptive gating reactor. This strategy provides an insight into constructing smart gating membranes with extraordinary properties, showing promising applications in micro/nanofluidic valves and temperature sensitive biochemical reactors

Fabrication and Applications of Multi-Fluidic Electrospinning Multi-Structure Hollow and Core–Shell Nanofibers

Recently, electrospinning (ESP) has been widely used as a synthetic technology to prepare nanofibers with unique properties from various raw materials. The applications of functionalized nanofibers have gradually developed into one of the most exciting topics in the field of materials science. In this review, we focus on the preparation of multi-structure fibrous nanomaterials by means of multi-fluidic ESP and review the applications of multi-structure nanofibers in energy, catalysis, and biology. First, the working principle and process of ESP are introduced; then, we demonstrate how the microfluidic concept is combined with the ESP technique to the multi-fluidic ESP technique. Subsequently, the applications of multi-structure nanofibers in energy (Li+/Na+ batteries and Li–S batteries), hetero-catalysis, and biology (drug delivery and tissue engineering) are introduced. Finally, challenges and future directions in this emerging field are summarized

The Construction of Three-Layered Biomimetic Arterial Graft Balances Biomechanics and Biocompatibility for Dynamic Biological Reconstruction

The process of reconstructing an arterial graft is a complex and dynamic process that is subject to the influence of various mechanical factors, including tissue regeneration and blood pressure. The attainment of favorable remodeling outcomes is contingent upon the biocompatibility and biomechanical properties of the arterial graft. A promising strategy involves the emulation of the three-layer structure of the native artery, wherein the inner layer is composed of polycaprolactone (PCL) fibers aligned with blood flow, exhibiting excellent biocompatibility that fosters endothelial cell growth and effectively prevents platelet adhesion. The middle layer, consisting of PCL and polyurethane (PU), offers mechanical support and stability by forming a contractile smooth muscle ring and antiexpansion PU network. The outer layer, composed of PCL fibers with an irregular arrangement, promotes the growth of nerves and pericytes for long-term vascular function. Prioritizing the reconstruction of the inner and outer layers establishes a stable environment for intermediate smooth muscle growth. Our three-layer arterial graft is designed to provide the blood vessel with mechanical support and stability through nondegradable PU, while the incorporation of degradable PCL generates potential spaces for tissue ingrowth, thereby transforming our graft into a living implant

Echocardiographic features of patients with heart failure and preserved left ventricular ejection fraction

Background: The PARAGON-HF (Prospective Comparison of ARNI With ARB Global Outcomes in HF With Preserved Ejection Fraction) trial tested the efficacy of sacubitril-valsartan in patients with heart failure with preserved ejection fraction (HFpEF). Existing data on cardiac structure and function in patients with HFpEF suggest significant heterogeneity. Objectives: The aim of this study was to characterize cardiac structure and function, quantify their associations with clinical outcomes, and contextualize these findings with other HFpEF studies. Methods: Echocardiography was performed in 1,097 of 4,822 PARAGON-HF patients within 6 months of enrollment. Associations with incident first heart failure hospitalization or cardiovascular death were assessed using Cox proportional hazards models adjusted for age, sex, region of enrollment, randomized treatment, N-terminal pro–brain natriuretic peptide, and clinical risk factors. Results: Average age was 74 ± 8 years, 53% of patients were women, median N-terminal pro–brain natriuretic peptide level was 918 pg/ml (interquartile range: 485 to 1,578 pg/ml), 94% had hypertension, and 35% had atrial fibrillation. The mean left ventricular (LV) ejection fraction was 58.6 ± 9.8%, prevalence of LV hypertrophy was 21%, prevalence of left atrial enlargement was 83%, prevalence of elevated E/e′ ratio was 53%, and prevalence of pulmonary hypertension was 31%. Heart failure hospitalization or cardiovascular death occurred in 288 patients at 2.8-year median follow-up. In fully adjusted models, higher LV mass index (hazard ratio [HR]: 1.05 per 10 g/m2; 95% confidence interval [CI]: 1.00 to 1.10; p = 0.03), E/e′ ratio (HR: 1.04 per unit; 95% CI: 1.02 to 1.06; p < 0.001), pulmonary artery systolic pressure (HR: 1.51 per 10 mm Hg; 95% CI: 1.29 to 1.76; p < 0.001), and right ventricular end-diastolic area (HR: 1.04 per cm2; 95% CI: 1.01 to 1.07; p = 0.003) were each associated with this composite, while LV ejection fraction and left atrial size were not (p > 0.05 for all). Appreciable differences were observed in cardiac structure compared with other HFpEF clinical trials, despite similar E/e′ ratio, pulmonary artery systolic pressure, and event rates. Conclusions: Diastolic dysfunction, left atrial enlargement, and pulmonary hypertension were common in PARAGON-HF. LV hypertrophy, elevated left- and right-sided pressures, and right ventricular enlargement were independently predictive of incident heart failure hospitalization or cardiovascular death. Echocardiographic differences among HFpEF trials despite similar clinical event rates highlight the heterogeneity of this syndrome

Echocardiographic Features of Patients With Heart Failure and Preserved Left Ventricular Ejection Fraction

Background: The PARAGON-HF (Prospective Comparison of ARNI With ARB Global Outcomes in HF With Preserved Ejection Fraction) trial tested the efficacy of sacubitril-valsartan in patients with heart failure with preserved ejection fraction (HFpEF). Existing data on cardiac structure and function in patients with HFpEF suggest significant heterogeneity. Objectives: The aim of this study was to characterize cardiac structure and function, quantify their associations with clinical outcomes, and contextualize these findings with other HFpEF studies. Methods: Echocardiography was performed in 1,097 of 4,822 PARAGON-HF patients within 6 months of enrollment. Associations with incident first heart failure hospitalization or cardiovascular death were assessed using Cox proportional hazards models adjusted for age, sex, region of enrollment, randomized treatment, N-terminal pro–brain natriuretic peptide, and clinical risk factors. Results: Average age was 74 ± 8 years, 53% of patients were women, median N-terminal pro–brain natriuretic peptide level was 918 pg/ml (interquartile range: 485 to 1,578 pg/ml), 94% had hypertension, and 35% had atrial fibrillation. The mean left ventricular (LV) ejection fraction was 58.6 ± 9.8%, prevalence of LV hypertrophy was 21%, prevalence of left atrial enlargement was 83%, prevalence of elevated E/e′ ratio was 53%, and prevalence of pulmonary hypertension was 31%. Heart failure hospitalization or cardiovascular death occurred in 288 patients at 2.8-year median follow-up. In fully adjusted models, higher LV mass index (hazard ratio [HR]: 1.05 per 10 g/m2; 95% confidence interval [CI]: 1.00 to 1.10; p = 0.03), E/e′ ratio (HR: 1.04 per unit; 95% CI: 1.02 to 1.06; p < 0.001), pulmonary artery systolic pressure (HR: 1.51 per 10 mm Hg; 95% CI: 1.29 to 1.76; p < 0.001), and right ventricular end-diastolic area (HR: 1.04 per cm2; 95% CI: 1.01 to 1.07; p = 0.003) were each associated with this composite, while LV ejection fraction and left atrial size were not (p > 0.05 for all). Appreciable differences were observed in cardiac structure compared with other HFpEF clinical trials, despite similar E/e′ ratio, pulmonary artery systolic pressure, and event rates. Conclusions: Diastolic dysfunction, left atrial enlargement, and pulmonary hypertension were common in PARAGON-HF. LV hypertrophy, elevated left- and right-sided pressures, and right ventricular enlargement were independently predictive of incident heart failure hospitalization or cardiovascular death. Echocardiographic differences among HFpEF trials despite similar clinical event rates highlight the heterogeneity of this syndrome

Impact of sacubitril/valsartan compared to ramipril on cardiac structure and function following acute myocardial infarction: The PARADISE-MI echocardiographic sub-study

No abstract available