Search Results Heading

MBRLSearchResults

mbrl.module.common.modules.added.book.to.shelf
Title added to your shelf!
View what I already have on My Shelf.
Oops! Something went wrong.
Oops! Something went wrong.
While trying to add the title to your shelf something went wrong :( Kindly try again later!
Are you sure you want to remove the book from the shelf?
Oops! Something went wrong.
Oops! Something went wrong.
While trying to remove the title from your shelf something went wrong :( Kindly try again later!
    Done
    Filters
    Reset
  • Discipline
      Discipline
      Clear All
      Discipline
  • Is Peer Reviewed
      Is Peer Reviewed
      Clear All
      Is Peer Reviewed
  • Item Type
      Item Type
      Clear All
      Item Type
  • Subject
      Subject
      Clear All
      Subject
  • Year
      Year
      Clear All
      From:
      -
      To:
  • More Filters
37 result(s) for "Meng, Xiang-Min"
Sort by:
A Novel Terminal Sliding Mode Variable Structure Model Reference Adaptive System Observer for Permanent Magnet Synchronous Motors
This paper introduces a model reference adaptive system observer based on the non-singular fast terminal sliding mode (NFSM-MRASO) for the purpose of sensorless control of permanent magnet synchronous motors (PMSMs) in electric vehicle applications. Firstly, a non-singular fast terminal sliding surface is constructed based on the output errors of the reference model and the adjustable model. This ensures that the output errors between the two models converge to zero in a finite time and effectively avoids the singularity problem in the terminal sliding mode control. In addition, a novel reaching law (NRL) is designed to replace the traditional exponential reaching law (TRL) to suppress the chattering phenomenon in the sliding mode control. Finally, the feasibility and effectiveness of the NFSM-MRASO strategy are demonstrated through simulation results.
Acupuncture at Neiguan suppresses PVCs occurring post-myocardial infarction by alleviating inflammation and fibrosis
Background Acupuncture at Neiguan (PC6) has long been used for treating cardiovascular diseases, but its antiarrhythmic effect and the underlying mechanisms have not yet been well investigated, especially regarding premature ventricular complexes (PVCs) that occur post-myocardial infarction (MI). The purpose of this study was to study the antiarrhythmic effect of manual acupuncture applied to PC6 for a relatively long period (28 days) and to elucidate the mechanism in mice . Methods An MI mouse model was generated by ligating the left anterior descending coronary artery in male C57/BL6 mice (n = 31). Manual acupuncture at PC6 was applied seven times weekly for 4 weeks. The state of myocardial injury was characterized by electrocardiography (ECG) and echocardiography. Inflammation was detected by ELISA and immunohistochemical stanning. Fibrosis was evaluated by Masson’s trichrome staining. RNA sequencing was used to explore the differentially expressed genes (DEGs) among the different groups after treatment. Results Acupuncture at PC6 lowered the incidence of spontaneous PVCs after MI injury (1/9, 11%) compared to that in mice without acupuncture treatment (6/9, 67%) and improved the ejection fraction from 31.77% in the MI mice to 44.18% in the MI + PC6 mice. Fibrosis was reduced after PC6 treatment. RNA-seq showed many DEGs involved in the immune system and inflammatory response pathway. Further studies confirmed that inflammation at the circulation level and cardiac tissue was inhibited in MI + PC6 mice, accompanied by suppressed sympathetic activation. Conclusions In conclusion, 28-day treatment of acupuncture at PC6 reduced spontaneous PVCs and improved systolic function, possibly by suppressing inflammatory response-mediated fibrosis and sympathetic hyperactivity.
Effects of different frequencies of repetitive transcranial magnetic stimulation on the recovery of upper limb motor dysfunction in patients with subacute cerebral infarction
Studies have confirmed that low-frequency repetitive transcranial magnetic stimulation can decrease the activity of cortical neurons, and high-frequency repetitive transcranial magnetic stimulation can increase the excitability of cortical neurons. However, there are few studies concerning the use of different frequencies of repetitive transcranial magnetic stimulation on the recovery of upper-limb motor function after cerebral infarction. We hypothesized that different frequencies of repetitive transcranial magnetic stimulation in patients with cerebral infarction would produce different effects on the recovery of upper-limb motor function. This study enrolled 127 patients with upper-limb dysfunction during the subacute phase of cerebral infarction. These patients were randomly assigned to three groups. The low-frequency group comprised 42 patients who were treated with 1 Hz repetitive transcranial magnetic stimulation on the contralateral hemisphere primary motor cortex (M1). The high-frequency group comprised 43 patients who were treated with 10 Hz repetitive transcranial magnetic stimulation on ipsilateral M1. Finally, the sham group comprised 42 patients who were treated with 10 Hz of false stimulation on ipsilateral M1. A total of 135 seconds of stimulation was applied in the sham group and high-frequency group. At 2 weeks after treatment, cortical latency of motor-evoked potentials and central motor conduction time were significantly lower compared with before treatment. Moreover, motor function scores were significantly improved. The above indices for the low- and high-frequency groups were significantly different compared with the sham group. However, there was no significant difference between the low- and high-frequency groups. The results show that low- and high-frequency repetitive transcranial magnetic stimulation can similarly improve upper-limb motor function in patients with cerebral infarction.
Histone methyltransferase KMT2D contributes to the protection of myocardial ischemic injury
Histone H3 lysine 4 (H3K4) methyltransferase 2D (KMT2D) plays an important role in cell development in early life. However, the function of KMT2D in adult cells such as cardiomyocytes or neurons has not been reported. In this study, cardiomyocyte-specific KMT2D knockout (KMT2D-cKO) and control (KMT2D-Ctl) mice were exposed to sham or myocardial ischemia (MI) surgery. Depletion of KMT2D aggravated the ischemic area, led to the increased mortality (26.5% in KMT2D-cKO vs 12.5% in KMT2D-Ctl) of the mice, and weakened the left ventricular systolic function. RNA-seq analysis in cardiac tissues identified genes whose expression was changed by MI and KMT2D deletion. Combined with the genome-wide association study (GWAS) analysis, cardiac disease-associated genes Rasd1 , Thsd7a , Ednra , and Tns1 were identified. The expression of the Rasd1 was significantly decreased by MI or the loss of KMT2D in vivo . Meanwhile, ChIP assays demonstrated that either MI or loss of KMT2D attenuated monomethylated H3K4 (H3K4me1) enrichment on the enhancer of Rasd1 . By generating a KMT2D knockout (H9C2-KO) H9C2 monoclone, we verified that the expression of Rasd1 was controlled by KMT2D, and the expression of Rasd1 was decreased by serum starvation but not low-(O 2 ) treatment in H9C2 cells. KMT2D has a protective effect on ischemic myocardium by regulating cardiac disease-associated genes including Rasd1 . KMT2D is required for the H3K4me1 deposition on the enhancer of Rasd1 . Our data for the first time suggest that KMT2D-mediated Rasd1 expression may play an important protective effect on adult cells during nutritional deficiency caused by ischemic injury.
Voltage Dependent Potassium Channel Remodeling in Murine Intestinal Smooth Muscle Hypertrophy Induced by Partial Obstruction
Partial obstruction of the small intestine causes obvious hypertrophy of smooth muscle cells and motility disorder in the bowel proximate to the obstruction. To identify electric remodeling of hypertrophic smooth muscles in partially obstructed murine small intestine, the patch-clamp and intracellular microelectrode recording methods were used to identify the possible electric remodeling and Western blot, immunofluorescence and immunoprecipitation were utilized to examine the channel protein expression and phosphorylation level changes in this research. After 14 days of obstruction, partial obstruction caused obvious smooth muscle hypertrophy in the proximally located intestine. The slow waves of intestinal smooth muscles in the dilated region were significantly suppressed, their amplitude and frequency were reduced, whilst the resting membrane potentials were depolarized compared with normal and sham animals. The current density of voltage dependent potassium channel (KV) was significantly decreased in the hypertrophic smooth muscle cells and the voltage sensitivity of KV activation was altered. The sensitivity of KV currents (IKV) to TEA, a nonselective potassium channel blocker, increased significantly, but the sensitivity of IKv to 4-AP, a KV blocker, stays the same. The protein levels of KV4.3 and KV2.2 were up-regulated in the hypertrophic smooth muscle cell membrane. The serine and threonine phosphorylation levels of KV4.3 and KV2.2 were significantly increased in the hypertrophic smooth muscle cells. Thus this study represents the first identification of KV channel remodeling in murine small intestinal smooth muscle hypertrophy induced by partial obstruction. The enhanced phosphorylations of KV4.3 and KV2.2 may be involved in this process.
Loss of Histone Methyltransferase KMT2D Attenuates Angiogenesis in the Ischemic Heart by Inhibiting the Transcriptional Activation of VEGF-A
Angiogenesis occurred after myocardial infarction (MI) protects heart failure (HF). The aim of our study was to explore function of histone methyltransferase KMT2D (MLL4, mixed-lineage leukemia 4) in angiogenesis post-MI. Western blotting showed that KMT2D protein expression was elevated in MI mouse myocardial. Cardiomyocyte-specific Kmt2d -knockout ( Kmt2d -cKO) mice were generated, and echocardiography and immunofluorescence staining detected significantly attenuated cardiac function and insufficient angiogenesis following MI in Kmt2d -cKO mice. Cross-talk assay suggested that Kmt2d-KO H9c2-derived conditioned medium attenuates EA.hy926 EC function. ELISA further identified that VEGF-A released from Kmt2d-KO H9c2 was significantly reduced. CUT&Tag and RT-qPCR revealed that KMT2D deficiency reduced Vegf-a mRNA expression and enrichment of H3K4me1 on the Vegf-a promoter. Moreover, KMT2D silencing in ECs also suppressed endothelial function. Our study indicates that KMT2D depletion in both cardiomyocytes and ECs attenuates angiogenesis and that loss of KMT2D exacerbates heart failure after MI in mice.
Comparative Study of Different Acupoints for Treating Acute Myocardial Ischemia in Mice
Acupuncture point specificity has been recognized as a key scientific issue in traditional Chinese medicine (TCM), but there is limited clinical trial or animal study to verify the characteristics of PC6, BL15, and ST36 in the protection from myocardial injury. We aimed to compare the effects among these three acupoints on the acute myocardial infarction mice model and to explore possible mechanisms for the first time. We found that PC6 is the most appropriate acupoint to deliver efficacy and safety to treat acute MI in mice. BL15 stimulation improved the systolic function, but increased the risk of arrhythmia. ST36 only slightly attenuated systolic function and had no effect on arrhythmia during MI. RNA profiles of skin tissue in local acupoints demonstrated that the most altered DEGs and related pathways may partly support its best effects of PC6 treatment on MI injury, and support the observed phenomenon of the acupoint specificity. Graphical abstract
Continuous-flow Mass Production of Silicon Nanowires via Substrate-Enhanced Metal-Catalyzed Electroless Etching of Silicon with Dissolved Oxygen as an Oxidant
Silicon nanowires (SiNWs) are attracting growing interest due to their unique properties and promising applications in photovoltaic devices, thermoelectric devices, lithium-ion batteries and biotechnology. Low-cost mass production of SiNWs is essential for SiNWs-based nanotechnology commercialization. However, economic, controlled large-scale production of SiNWs remains challenging and rarely attainable. Here, we demonstrate a facile strategy capable of low-cost, continuous-flow mass production of SiNWs on an industrial scale. The strategy relies on substrate-enhanced metal-catalyzed electroless etching (MCEE) of silicon using dissolved oxygen in aqueous hydrofluoric acid (HF) solution as an oxidant. The distinct advantages of this novel MCEE approach, such as simplicity, scalability and flexibility, make it an attractive alternative to conventional MCEE methods.
Synthesis, crystal structures and photocatalytic properties of Zn(II), Ni(II), Co(II) complexes with a symmetric open-chain N2O4-donor bis-Schiff base ligand
Three complexes, Zn(C 40 H 36 N 4 O 8 )·3CH 3 OH ( 1 ), Ni(C 40 H 36 N 4 O 8 )·3CH 3 OH ( 2 ) and Co(C 40 H 36 N 4 O 8 )·3CH 3 OH ( 3 ), with a sexidentate (N 2 O 4 ) symmetric bis-Schiff base ligand (C 40 H 36 N 4 O 8  = 1,2-bis(2-methoxy-6-formylphenoxy)ethane- l -tryptophan) have been synthesized and characterized by physicochemical and spectroscopic methods. The X-ray crystal structures show that the metal atoms of three complexes are all six-coordinated by two nitrogens from C=N groups, two oxygens from ether groups and two carboxylic oxygens in the mono-ligand, forming a distorted octahedral geometry. The complexes were screened as photocatalysts for the degradation of methylene blue, rhodamine B and methyl violet. All three complexes proved to be good candidates for the photocatalytic degradation of methylene blue and complexes 2–3 are also good photocatalysts for the degradation of rhodamine B. The mechanism of these photocatalytic degradations is discussed. Graphical Abstract The main characterization and photocatalytic experiment of three complexes.
Synthesis, crystal structures and biological evaluation of three ternary copper(II) complexes with fluorinated anthranilic acid derivatives
Three ternary copper(II) complexes [Cu(L1)(phen)] (1), [Cu(L2)(phen)] (2), and [Cu(L3)(phen)]·2H2O (3) (L1 = 4-fluoro-2-(picolinamido)benzoic acid, L2 = 4,5-difluoro-2-(picolinamido)benzoic acid, L3 = 4,5-difluoro-2-((2-hydroxybenzylidene)amino)benzoic acid, phen = 1,10-phenanthroline) have been synthesized and characterized by physicochemical and spectroscopic methods. In addition, X-ray crystallography showed that the Cu atoms in each of the complexes are five-coordinate, adopting distorted square pyramidal or trigonal bipyramidal geometries. The interactions of the complexes with calf-thymus DNA were investigated by UV absorption, fluorescence spectroscopy and viscosity measurements. In addition, the complexes were screened for in vitro cytotoxicity against A549 (human pulmonary carcinoma cells), Jurkat (human T lymphocyte cell line) and HepG-2 (human liver hepatocellular carcinoma cells); these experiments showed that complex 3 exhibited the most effective cytotoxicities (IC50 = 1.224–7.099 µM). Antibacterial studies revealed that complex 3 also exhibited highest activity, consistent with the DNA binding affinities.