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1.
Acta Pharmacol Sin ; 45(7): 1425-1437, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38839936

ABSTRACT

Cardiac fibrosis is a pathological scarring process that impairs cardiac function. N-acetyltransferase 10 (Nat10) is recently identified as the key enzyme for the N4-acetylcytidine (ac4C) modification of mRNAs. In this study, we investigated the role of Nat10 in cardiac fibrosis following myocardial infarction (MI) and the related mechanisms. MI was induced in mice by ligation of the left anterior descending coronary artery; cardiac function was assessed with echocardiography. We showed that both the mRNA and protein expression levels of Nat10 were significantly increased in the infarct zone and border zone 4 weeks post-MI, and the expression of Nat10 in cardiac fibroblasts was significantly higher compared with that in cardiomyocytes after MI. Fibroblast-specific overexpression of Nat10 promoted collagen deposition and induced cardiac systolic dysfunction post-MI in mice. Conversely, fibroblast-specific knockout of Nat10 markedly relieved cardiac function impairment and extracellular matrix remodeling following MI. We then conducted ac4C-RNA binding protein immunoprecipitation-sequencing (RIP-seq) in cardiac fibroblasts transfected with Nat10 siRNA, and revealed that angiomotin-like 1 (Amotl1), an upstream regulator of the Hippo signaling pathway, was the target gene of Nat10. We demonstrated that Nat10-mediated ac4C modification of Amotl1 increased its mRNA stability and translation in neonatal cardiac fibroblasts, thereby increasing the interaction of Amotl1 with yes-associated protein 1 (Yap) and facilitating Yap translocation into the nucleus. Intriguingly, silencing of Amotl1 or Yap, as well as treatment with verteporfin, a selective and potent Yap inhibitor, attenuated the Nat10 overexpression-induced proliferation of cardiac fibroblasts and prevented their differentiation into myofibroblasts in vitro. In conclusion, this study highlights Nat10 as a crucial regulator of myocardial fibrosis following MI injury through ac4C modification of upstream activators within the Hippo/Yap signaling pathway.


Subject(s)
Fibrosis , Mice, Inbred C57BL , Myocardial Infarction , Animals , Myocardial Infarction/metabolism , Myocardial Infarction/pathology , Mice , Male , YAP-Signaling Proteins/metabolism , Fibroblasts/metabolism , Cytidine/analogs & derivatives , Cytidine/pharmacology , Mice, Knockout , Membrane Proteins/metabolism , Membrane Proteins/genetics , N-Terminal Acetyltransferase E/metabolism , Hippo Signaling Pathway , Myocytes, Cardiac/metabolism , Myocytes, Cardiac/pathology , Cells, Cultured , Signal Transduction , N-Terminal Acetyltransferases/metabolism , Myocardium/pathology , Myocardium/metabolism , Adaptor Proteins, Signal Transducing/metabolism
2.
Huan Jing Ke Xue ; 44(7): 3978-3989, 2023 Jul 08.
Article in Chinese | MEDLINE | ID: mdl-37438296

ABSTRACT

In order to improve the stability and catalytic activity of Fe-TAML, mono-6-oxy-cyclodextrin bonded Fe-TAML catalyst (CD-Fe-TAML) was prepared by bonding Fe-TAML with cyclodextrin (CD) through chlorosulfonylation reaction, metal chelation reaction, and nucleophilic substitution reaction. The catalytic activity and stability of CD-Fe-TAML and the oxidation degradation efficiencies of 34 organic micropollutants such as antibiotics and pesticides by activation of H2O2in water were studied. Compared with that of Fe-TAML, CD-Fe-TAML at pH 7.0 had a 49-fold and 25-fold increase in the rate of activating H2O2 to produce iron (Ⅴ/Ⅳ)-oxo intermediates and the degradation rate of the substrate, respectively, and its self-oxidation rate was reduced by 70%. The stability of CD-Fe-TAML was 0.7-699 times higher than that of Fe-TAML in the pH range of 3.0-10.0. Specifically, the stability of CD-Fe-TAML was 33-699 times higher than that of Fe-TAML in the pH range of 3.0-7.0. The sulfonic acid group in the molecular structure of CD-Fe-TAML had an electrophilic effect, which could increase the positive charge density of Fe in the active center, accelerate the O-O bond cleavage of H2O2 and the generation of iron(Ⅴ/Ⅳ)-oxo intermediates, improve the catalytic activity of Fe-TAML, and also improve its hydrolysis stability. Meanwhile, the CD group in the molecular structure had the "electron shuttle" effect and inclusion effect. The former could accelerate the electron transfer between the active center Fe-TAML and H2O2 to improve the catalytic activity of Fe-TAML. The latter could inhibit the hydrolysis and self-oxidation of the active center Fe-TAML by inclusion or binding of the hydrolysis sites and oxidation sites, thus improving its stability. The degradation efficiencies of micropollutants by CD-Fe-TAML/H2O2 under weakly acidic and neutral conditions (in the pH range of 5.0-7.0) were 0.4-59 times higher than those of Fe-TAML/H2O2. The degradation efficiencies of CD-Fe-TAML/H2O2 on nine micropollutants with a molar volume less than 0.20 L·mol-1, such as acetamiprid and sulfadiazine, were 0.3-1.1 times higher than that of Fe-TAML/H2O2 at pH 8.0, and there were no significant differences between CD-Fe-TAML/H2O2 and Fe-TAML/H2O2for micropollutants with a molar volume greater than 0.20 L·mol-1. The results of iodide oxidation by CD-Fe-TAML/H2O2 showed that I- was not oxidized to produce iodo-disinfection byproducts (I-DBPs). The degradation of micropollutants by CD-Fe-TAML/H2O2 in the surface water sample was not disturbed by water components. The CD-Fe-TAML/H2O2 system has a potential application in the removal of organic micropollutants from water.

3.
Medicine (Baltimore) ; 102(15): e33502, 2023 Apr 14.
Article in English | MEDLINE | ID: mdl-37058074

ABSTRACT

To investigate the clinical phenotype-genotype correlations of a family with Kennedy disease (KD) and improve our understanding of the disease. KD was confirmed after clinical phenotypic analyses, laboratory tests, polymerase chain reaction assays for cytosine-adenine-guanine (CAG) repeats, and neuro-electrophysiological tests. The disease was assessed using the KD1234 scale and the spinal and bulbar muscular atrophy functional rating scale. The average age of disease onset was 30.8 ± 2.85 years. Clinically diagnosed members had 48 CAG repeats (≥35 is abnormal) in the androgen receptor gene. The patients exhibited gynecomastia and testicular dysfunction. The lesions mainly involved the medulla oblongata and spinal cord. Progesterone and serum creatine kinase levels were significantly high. Electromyography showed chronic neurogenic damage and abnormal sensory and motor conduction in family members who did not participate in sports, exercise, or physical hobbies. Our study showed that this family had a stable inheritance of CAG repeats, and the genotype was consistent with the clinical phenotype. Gynecomastia was the first symptom, with progressive androgen resistance resulting in testicular atrophy, infertility, and sexual dysfunction. Changes in serum creatine kinase may indicate the progression or relief of symptoms, and rehabilitation may delay the progression of muscle atrophy.


Subject(s)
Bulbo-Spinal Atrophy, X-Linked , Gynecomastia , Muscular Atrophy, Spinal , Humans , Male , Bulbo-Spinal Atrophy, X-Linked/genetics , Bulbo-Spinal Atrophy, X-Linked/diagnosis , Genotype , Phenotype , Muscular Atrophy , Creatine Kinase , Receptors, Androgen/genetics , Muscular Atrophy, Spinal/genetics
4.
Int J Biol Sci ; 19(3): 994-1006, 2023.
Article in English | MEDLINE | ID: mdl-36778116

ABSTRACT

Cardiac fibrosis is a common pathological cardiac remodeling in a variety of heart diseases, characterized by the activation of cardiac fibroblasts. Our previous study uncovered that promyelocytic leukemia protein (PML)-associated SUMO processes is a new regulator of cardiac hypertrophy and heart failure. The present study aimed to explore the role of PML in cardiac fibroblasts activation. Here we found that PML is significantly upregulated in cardiac fibrotic tissue and activated cardiac fibroblasts treated with transforming growth factor-ß1 (TGF-ß1). Gain- and loss-of-function experiments showed that PML impacted cardiac fibroblasts activation after TGF-ß1 treatment. Further study demonstrated that p53 acts as the transcriptional regulator of PML, and participated in TGF-ß1 induced the increase of PML expression and PML nuclear bodies (PML-NBs) formation. Knockdown or pharmacological inhibition of p53 produced inhibitory effects on the activation of cardiac fibroblasts. We further found that PML also may stabilize p53 through inhibiting its ubiquitin-mediated proteasomal degradation in cardiac fibroblasts. Collectively, this study suggests that PML crosstalk with p53 regulates cardiac fibroblasts activation, which provides a novel therapeutic strategy for cardiac fibrosis.


Subject(s)
Promyelocytic Leukemia Protein , Transforming Growth Factor beta1 , Tumor Suppressor Protein p53 , Humans , Fibroblasts/metabolism , Fibrosis , Heart , Transforming Growth Factor beta1/pharmacology , Tumor Suppressor Protein p53/metabolism , Promyelocytic Leukemia Protein/metabolism
5.
World J Clin Cases ; 10(1): 304-308, 2022 Jan 07.
Article in English | MEDLINE | ID: mdl-35071532

ABSTRACT

BACKGROUND: Laparoscopic cervical cerclage is performed for patients with abnormal cervical anatomy and/or transvaginal cervical cerclage failure. However, the method of removing the stitches to allow labour induction remains controversial. According to published literature, stitches are removed through laparoscopic or transvaginal methods. Herein, we report, for the first time, a case of a patient who had undergone laparoscopic cerclage, and then underwent removal of stitches by laparotomy and labour induction in the third trimester of pregnancy. CASE SUMMARY: A patient who underwent laparoscopic cervical cerclage due to cervical insufficiency became pregnant naturally following the operation. At 31 wk of pregnancy, severe foetal malformations were found. To successfully induce labour, cerclage stitches were removed via laparotomy, and rivanol was injected directly into the uterus. Following successful induction of labour, the patient delivered a dead foetus. CONCLUSION: This report provides a reliable scheme of removing cerclage stitches for patients who have undergone laparoscopic cerclage but experience severe foetal malformations.

6.
Cardiovasc Ther ; 2022: 6806427, 2022.
Article in English | MEDLINE | ID: mdl-35082919

ABSTRACT

OBJECTIVE: Remote ischemic conditioning (RIC) is a cardioprotective method in ischemia/reperfusion (I/R) injury. This study investigated the mechanism of Rho-kinase-mediated autophagy in RIC. METHODS: Sixty male Sprague-Dawley rats were randomly divided into six groups: sham, I/R, RIC, I/R+fasudil, RIC+wortmannin, and RIC+fasudil+wortmannin. Throughout the experiment, mean arterial pressure and heart rate were continuously monitored. Histopathology and ultrastructure and myocardial enzymes' expression were evaluated to determine the degree of cardiac injury. The protein expression of the Rho-kinase substrates myosin light chain (MLC) and myosin phosphatase target subunit 1 (MYPT1), autophagy-related protein light chain 3-II (LC3-II) and Beclin 1, and protein kinase B (AKT) was measured in the myocardial tissue. RESULTS: Compared with the sham group, the mean arterial pressure and heart rate were decreased, myocardial enzyme levels were increased, and myocardial damage was aggravated in the I/R group; however, RIC improved these alterations. The expression of phosphorylated MLC and MYPT1 was lower, while LC3-II, Beclin 1, and phospho-AKT expression levels were higher in the RIC group compared with the I/R group. Obviously, treatment of the I/R group rats with fasudil, a Rho-kinase inhibitor, significantly ameliorated the I/R effects, whereas treatment of the RIC group rats with wortmannin, a phosphatidylinositol-3 kinase (PI3K) inhibitor, inhibited the RIC protective effects. Moreover, the rats in the RIC+fasudil+wortmannin group showed similar changes to those in the RIC+wortmannin group. CONCLUSION: These results showed that RIC protected the myocardium from I/R injury by suppressing Rho-kinase and the underlying mechanism may be related to enhancing autophagy via the PI3K/AKT pathway.


Subject(s)
Myocardial Reperfusion Injury , Animals , Autophagy , Ischemia , Male , Myocardial Reperfusion Injury/prevention & control , Phosphatidylinositol 3-Kinases , Proto-Oncogene Proteins c-akt , Rats , Rats, Sprague-Dawley , rho-Associated Kinases
7.
Int J Hyg Environ Health ; 234: 113738, 2021 05.
Article in English | MEDLINE | ID: mdl-33752171

ABSTRACT

AIM: Living in areas with neighborhood greenness may be associated with the incidence of cardiovascular diseases (CVDs). However, little evidence in this regard has emerged from developing countries. In the present study, we examined neighborhood greenness associated with CVDs and the lipid accumulation product (LAP) and pulse pressure (PP) in China. METHODS: We undertook our analysis using a community cross-sectional survey conducted in Longzihu District of Bengbu from July to August 2015. We measured triglyceride levels, waist circumference, and blood pressure. To assess exposure to neighborhood greenness, we used the average normalized difference vegetation index (NDVI) at 1,000-, 1,500-, and 2,000-m buffers in the participant community. We employed generalized mixed models to determine the association among neighborhood greenness, CVDs, LAP, and PP. We conducted stratified analysis by age, gender, income, and education. We assessed the potential mediating effects of road proximity and physical activity on greenness and CVDs, PP, and LAP. RESULTS: The highest tertiles of NDVI1500-m were steadily and significantly associated with lower odds of CVDs prevalence: the adjusted OR of such prevalence was 0.612 (95% CI, 0.462-0.811); higher NDVI was significantly associated with lower PP levels. The NDVI was strongly associated with CVDs prevalence among participants who were male and had high income. Ambient road proximity significantly mediated 9.7% of the estimated association between greenness and PP, there was no evidence of mediation effects for physical activity. CONCLUSIONS: Higher neighborhood greenness could have a beneficial effect on CVDs and biomarkers. There were higher associations between residential greenness and CVDs among male and higher-income individuals; road proximity partially mediated the observed association between greenness and PP.


Subject(s)
Cardiovascular Diseases , Biomarkers , Cardiovascular Diseases/epidemiology , Cross-Sectional Studies , Exercise , Humans , Male , Residence Characteristics
8.
Acta Pharmacol Sin ; 42(6): 921-931, 2021 Jun.
Article in English | MEDLINE | ID: mdl-32839503

ABSTRACT

The neonatal heart possesses the ability to proliferate and the capacity to regenerate after injury; however, the mechanisms underlying these processes are not fully understood. Melatonin has been shown to protect the heart against myocardial injury through mitigating oxidative stress, reducing apoptosis, inhibiting mitochondrial fission, etc. In this study, we investigated whether melatonin regulated cardiomyocyte proliferation and promoted cardiac repair in mice with myocardial infarction (MI), which was induced by ligation of the left anterior descending coronary artery. We showed that melatonin administration significantly improved the cardiac functions accompanied by markedly enhanced cardiomyocyte proliferation in MI mice. In neonatal mouse cardiomyocytes, treatment with melatonin (1 µM) greatly suppressed miR-143-3p levels. Silencing of miR-143-3p stimulated cardiomyocytes to re-enter the cell cycle. On the contrary, overexpression of miR-143-3p inhibited the mitosis of cardiomyocytes and abrogated cardiomyocyte mitosis induced by exposure to melatonin. Moreover, Yap and Ctnnd1 were identified as the target genes of miR-143-3p. In cardiomyocytes, inhibition of miR-143-3p increased the protein expression of Yap and Ctnnd1. Melatonin treatment also enhanced Yap and Ctnnd1 protein levels. Furthermore, Yap siRNA and Ctnnd1 siRNA attenuated melatonin-induced cell cycle re-entry of cardiomyocytes. We showed that the effect of melatonin on cardiomyocyte proliferation and cardiac regeneration was impeded by the melatonin receptor inhibitor luzindole. Silencing miR-143-3p abrogated the inhibition of luzindole on cardiomyocyte proliferation. In addition, both MT1 and MT2 siRNA could cancel the beneficial effects of melatonin on cardiomyocyte proliferation. Collectively, the results suggest that melatonin induces cardiomyocyte proliferation and heart regeneration after MI by regulating the miR-143-3p/Yap/Ctnnd1 signaling pathway, providing a new therapeutic strategy for cardiac regeneration.


Subject(s)
Cell Proliferation/drug effects , Melatonin/therapeutic use , Myocardial Infarction/drug therapy , Myocytes, Cardiac/metabolism , Signal Transduction/drug effects , Adaptor Proteins, Signal Transducing/metabolism , Animals , Animals, Newborn , Catenins/metabolism , Cell Cycle/drug effects , Cells, Cultured , Heart/drug effects , Mice, Inbred C57BL , MicroRNAs/metabolism , Myocardial Infarction/metabolism , Myocardium/metabolism , Receptor, Melatonin, MT1/metabolism , Receptor, Melatonin, MT2/metabolism , Regeneration/drug effects , YAP-Signaling Proteins , Delta Catenin
9.
Entropy (Basel) ; 22(1)2020 Jan 06.
Article in English | MEDLINE | ID: mdl-33285846

ABSTRACT

Scientific experimental racks are an indispensable supporter in space stations for experiments with regard to meeting different temperature and humidity requirements. The diversity of experiments brings enormous challenges to the thermal control system of racks. This paper presents an indirect coupling thermal control single-phase fluid loop system for scientific experimental racks, along with fuzzy incremental control strategies. A dynamic model of the thermal control system is built, and three control strategies for it, with different inputs and outputs, are simulated. A comparison of the calculated results showed that pump speed and outlet temperature of the cold plate branch are, respectively, the best choice for the control variable and controlled variable in the controller. It showed that an indirect coupling thermal control fluid loop system with a fuzzy incremental controller is feasible for the thermal control of scientific experimental racks in space stations.

10.
Sci Rep ; 10(1): 3258, 2020 Feb 24.
Article in English | MEDLINE | ID: mdl-32094389

ABSTRACT

In this paper, we present to achieve a broadband miniaturized transmission waveguide based on complementary spoof surface plasmon polaritons (CSSPPs). For this purpose, a novel SSPP design that consists of a corrugated slot line and a group of additional interdigital structures (ISs) is proposed, which brings in an extra solution to control the cut-off property of CSSPPs. The transmission cut-off frequency of the proposed design decreases with the increasing of the number of the ISs. Since the width of CSSPP waveguide is directly related to the operating frequency, the degree of miniaturization can be modulated freely by carefully choosing the number of the ISs. A prototype of device with four-ISs introduced is designed and fabricated. And the cut-off frequency of the design decreases from 10 GHz to 5.3 GHz, when the ISs are added. Experimental results agree well with the numerical simulations. The proposed design illustrates great potentials in modern plasmonic integrated circuits.

11.
Zhongguo Zhong Yao Za Zhi ; 44(17): 3792-3797, 2019 Sep.
Article in Chinese | MEDLINE | ID: mdl-31602955

ABSTRACT

This paper was aimed to establish screening methods of anaphylactoid reaction caused by safflower yellow for injection based on RBL-2 H3 cell degranulation model and mice model for acute anaphylactoid reaction,and evaluate the hypersensitivity caused by safflower yellow for injection from different batches. An in vitro cell model was used to keep the cells stimulated for an hour with different batches of safflower yellow for injection as the drug group,serum-free MEM medium as negative control group and 30 mg·L-1 C48/80 as positive control group respectively. The supernatant was then absorbed,and neutral red staining technique was used to detect the effect of safflower yellow injection on the degranulation of RBL-2 H3 cells with the positive cell rate of degranulation as the indicator.An in vivo model was established to validate the experimental results,and mice model for acute anaphylactoid reaction and ELISA method were adopted to detect the plasma histamine content,and screen the hypersensitivity caused by safflower yellow for injection at the animal level by using plasma histamine content as a test index. The results of the neutral red staining experiments showed that the positive control C48/80 could cause cell degranulation,and most of the cells were deeply stained. There was significant difference in positive cell rate between different batches of safflower yellow and positive control group. In the mice model for acute anaphylactoid reaction,it was found that the positive control C48/80 significantly increased the histamine content in the plasma of mice,while the safflower yellow in each batch did not cause a significant increase in plasma histamine( P<0. 000 1). The mechanism of anaphylactoid reaction is relatively complicated. This study was mainly based on the release of histamine and other active substances by degranulation of mast cells. No significant degranulation reaction of RBL-2 H3 cells induced by safflower yellow for injection was detected,nor was the plasma histamine level significantly increased in mice from the in vitro and in vivo aspects.


Subject(s)
Anaphylaxis/chemically induced , Cell Degranulation/drug effects , Chalcone/analogs & derivatives , Mast Cells/drug effects , Animals , Cells, Cultured , Chalcone/adverse effects , Histamine/blood , Mice
12.
Theor Appl Genet ; 132(5): 1363-1373, 2019 May.
Article in English | MEDLINE | ID: mdl-30680420

ABSTRACT

KEY MESSAGE: A major, likely novel stripe rust resistance QTL for all-stage resistance on chromosome arm 1BL identified in a 1.76-cM interval using a saturated linkage map was validated in four populations with different genetic backgrounds. Stripe rust is a globally important disease of wheat. Identification and utilization of new resistance genes are essential for breeding resistant cultivars. Wheat line 20828 has exhibited high levels of stripe rust resistance for over a decade. However, the genetics of stripe rust resistance in this line has not been studied. A set of 199 recombinant inbred lines (RILs) were developed from a cross between 20828 and a susceptible cultivar Chuannong 16. The RIL population was genotyped with the Wheat55K SNP (single nucleotide polymorphism) array and SSR (simple sequence repeat) markers and evaluated in four environments with current predominant Puccinia striiformis f. sp. tritici t races including CYR32, CYR33 and CYR34. Four stable QTL were located on chromosomes 1B (2 QTL), 4A and 6A. Among them, the major QTL, QYr.sicau-1B.1 (LOD = 23-28, PVE = 16-39%), was localized to a 1.76-cM interval flanked by SSR markers Xwmc216 and Xwmc156 on chromosome 1BL. Eight resistance genes were previously identified in the physical interval of QYr.sicau-1B.1. Compared with previous studies, QYr.sicau-1B.1 is a new gene for resistant to stripe rust. It was further verified by analysis of the closely linked SSR markers Xwmc216 and Xwmc156 in four other populations with different genetic backgrounds. QYr.sicau-1B.1 reduced the stripe rust disease index by up to 82.8%. Three minor stable QTL (located on chromosomes 1B, 4A and 6A, respectively) also added to the resistance level of QYr.sicau-1B.1. Our results provide valuable information for further fine mapping and cloning as well as molecular-assisted breeding with QYr.sicau-1B.1.


Subject(s)
Disease Resistance/genetics , Quantitative Trait Loci , Triticum/genetics , Breeding , Chromosome Mapping , Crosses, Genetic , Genotype , Polymorphism, Single Nucleotide , Triticum/microbiology
13.
Eur J Pharmacol ; 818: 604-609, 2018 Jan 05.
Article in English | MEDLINE | ID: mdl-29166571

ABSTRACT

The purpose of the present work was designed to explore protective cerebrovascular effects of hydroxysafflor yellow A (HSYA), and provide preclinical efficacy and mechanism data for its possible application in patients with cerebral ischemia. The protective effect of HSYA on ischemic stroke was evaluated by infarct sizes and neurological scores in Sprague-Dawley (SD) rats with middle cerebral artery occlusion (MCAO). Cerebrovascular permeability was detected by Evans blue dye leakage in MCAO rats. Cerebral blood flow, as well as blood pressure and heart rate were monitored using flow probes in Beagle dogs. Basilar artery tension isolated from Beagle dogs was evaluated with an MPA 2000 data-acquisition system. Coagulation-related function was also judged, including rabbit platelet aggregation by adenosine diphosphate (ADP) and platelet-aggregating factor (PAF), rabbit blood viscosity by a blood viscometer, and thrombus formation by rat arterial-venous shunts. Results showed that HSYA treatment significantly decreased the infarct sizes, neurological scores and cerebrovascular permeability in rats with MCAO. However, cerebral blood flow, blood pressure and heart rate were not affected by HSYA. In vitro, HSYA had a strong effect on cerebrovascular vasodilatation, and significantly decreased platelet aggregation, blood viscosity, and thrombogenesis. Besides well-known anti-coagulation effects, HSYA protects against ischemic stroke by dilating cerebral vessels and improving cerebrovascular permeability.


Subject(s)
Brain Ischemia/complications , Brain/blood supply , Chalcone/analogs & derivatives , Quinones/pharmacology , Stroke/prevention & control , Stroke/physiopathology , Animals , Basilar Artery/drug effects , Basilar Artery/physiopathology , Blood Pressure/drug effects , Blood Viscosity/drug effects , Brain/drug effects , Cerebrovascular Circulation/drug effects , Chalcone/pharmacology , Coronary Vessels/drug effects , Coronary Vessels/physiopathology , Dogs , Heart Rate/drug effects , Permeability/drug effects , Platelet Aggregation/drug effects , Rabbits , Rats , Stroke/complications , Stroke/metabolism , Thrombosis/prevention & control , Vasodilation/drug effects
14.
Sci Rep ; 6: 29600, 2016 07 12.
Article in English | MEDLINE | ID: mdl-27404740

ABSTRACT

The plasmonic waveguide made of uniform corrugated metallic strip can support and guide spoof surface plasmon polaritons (SSPPs) with high confinements. Here, we propose periodically-modulated plasmonic waveguide composed of non-uniform corrugated metallic strip to convert SSPPs to radiating waves, in which the main beam of radiations can steer continuously as the frequency changes. To increase the radiation efficiency of the periodically-modulated plasmonic waveguide at the broadside, an asymmetrical plasmonic waveguide is further presented to reduce the reflections and realize continuous leaky-wave scanning. Both numerical simulations and experimental results show that the radiation efficiency can be improved greatly and the main beam of leaky-wave radiations can steer from the backward quadrant to the forward quadrant, passing through the broadside direction, which generally is difficult to be realized by the common leaky-wave antennas.

15.
Adv Protein Chem Struct Biol ; 104: 233-261, 2016.
Article in English | MEDLINE | ID: mdl-27038376

ABSTRACT

Ca(2+)-activated K(+) channels (KCa) are classified into three subtypes: big conductance (BKCa), intermediate conductance (IKCa), and small conductance (SKCa) KCa channels. The three types of KCa channels have distinct physiological or pathological functions in cardiovascular system. BKCa channels are mainly expressed in vascular smooth muscle cells (VSMCs) and inner mitochondrial membrane of cardiomyocytes, activation of BKCa channels in these locations results in vasodilation and cardioprotection against cardiac ischemia. IKCa channels are expressed in VSMCs, endothelial cells, and cardiac fibroblasts and involved in vascular smooth muscle proliferation, migration, vessel dilation, and cardiac fibrosis. SKCa channels are widely expressed in nervous and cardiovascular system, and activation of SKCa channels mainly contributes membrane hyperpolarization. In this chapter, we summarize the physiological and pathological roles of the three types of KCa channels in cardiovascular system and put forward the possibility of KCa channels as potential target for cardiovascular diseases.


Subject(s)
Cardiovascular Diseases/genetics , Cardiovascular System/metabolism , Molecular Targeted Therapy , Potassium Channels, Calcium-Activated/genetics , Cardiovascular Diseases/pathology , Endothelial Cells/metabolism , Humans , Muscle, Smooth, Vascular/metabolism , Muscle, Smooth, Vascular/pathology , Potassium Channels, Calcium-Activated/chemistry , Potassium Channels, Calcium-Activated/metabolism
16.
Sci Rep ; 6: 23974, 2016 Apr 01.
Article in English | MEDLINE | ID: mdl-27035269

ABSTRACT

One-dimensional (1D) subwavelength corrugated metal structures has been described to support spoof surface plasmon polaritons (SPPs). Here we demonstrate that a periodically modulated 1D subwavelength corrugated metal structure can convert spoof SPPs to propagating waves. The structure is fed at the center through a slit with a connected waveguide on the input side. The subwavelength corrugated metal structure on the output surface is regarded as metasurface and modulated periodically to realize the leaky-wave radiation at the broadside. The surface impedance of the corrugated metal structure is modulated by using cosine function and triangle-wave function, respectively, to reach the radiation effect. Full wave simulations and measuremental results are presented to validate the proposed design.

17.
Sci Rep ; 5: 18170, 2015 Dec 10.
Article in English | MEDLINE | ID: mdl-26658471

ABSTRACT

Metasurfaces have huge potentials to develop new type imaging systems due to their abilities of controlling electromagnetic waves. Here, we propose a new method for dual-sensor imaging based on cross-like holographic leaky-wave metasurfaces which are composed of hybrid isotropic and anisotropic surface impedance textures. The holographic leaky-wave radiations are generated by special impedance modulations of surface waves excited by the sensor ports. For one independent sensor, the main leaky-wave radiation beam can be scanned by frequency in one-dimensional space, while the frequency scanning in the orthogonal spatial dimension is accomplished by the other sensor. Thus, for a probed object, the imaging plane can be illuminated adequately to obtain the two-dimensional backward scattered fields by the dual-sensor for reconstructing the object. The relativity of beams under different frequencies is very low due to the frequency-scanning beam performance rather than the random beam radiations operated by frequency, and the multi-illuminations with low relativity are very appropriate for multi-mode imaging method with high resolution and anti- noise. Good reconstruction results are given to validate the proposed imaging method.

18.
Sci Rep ; 5: 15853, 2015 Nov 03.
Article in English | MEDLINE | ID: mdl-26527420

ABSTRACT

We propose a method for dual-channel near-field manipulations by designing isotropic but inhomogeneous metasurfaces. As example, we present a dual-channel near-field focusing metasurface device. When the device is driven by surface waves from different channels on the metasurface, the near fields will be focused at the same spatial point with different polarizations. Conversely, if a linearly polarized source is radiated at the spatial focal point, different channels will be evoked on the metasurface controlled by polarization. We fabricated and measured the metasurface device in the microwave frequency. Well agreements between the simulation and measurement results are observed. The proposed method exhibits great flexibility in controlling the surface waves and spatial waves simultaneously. It is expected that the proposed method and dual-channel device will facilitate the manipulation of near electromagnetic or optical waves in different frequency regimes.

19.
Opt Express ; 23(6): 7593-601, 2015 Mar 23.
Article in English | MEDLINE | ID: mdl-25837097

ABSTRACT

We propose to use backward radiations of leaky waves supported by a holographic metasurface to produce spatial Bessel beams in the microwave frequency regime. The holographic metasurface consists of a grounded dielectric slab and a series of metal patches. By changing the size of metal patches, the surface-impedance distribution of the holographic metasurface can be modulated, and hence the radiation properties of the leaky waves can be designed to realize Bessel beams. Both numerical simulations and experiments verify the features of spatial Bessel beams, which may be useful in imaging applications or wireless power transmissions with the dynamic focal-depth controls.

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