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
31 result(s) for "Li, Dazhu"
Sort by:
Eosinophils improve cardiac function after myocardial infarction
Clinical studies reveal changes in blood eosinophil counts and eosinophil cationic proteins that may serve as risk factors for human coronary heart diseases. Here we report an increase of blood or heart eosinophil counts in humans and mice after myocardial infarction (MI), mostly in the infarct region. Genetic or inducible depletion of eosinophils exacerbates cardiac dysfunction, cell death, and fibrosis post-MI, with concurrent acute increase of heart and chronic increase of splenic neutrophils and monocytes. Mechanistic studies reveal roles of eosinophil IL4 and cationic protein mEar1 in blocking H 2 O 2 - and hypoxia-induced mouse and human cardiomyocyte death, TGF-β-induced cardiac fibroblast Smad2/3 activation, and TNF-α-induced neutrophil adhesion on the heart endothelial cell monolayer. In vitro-cultured eosinophils from WT mice or recombinant mEar1 protein, but not eosinophils from IL4-deficient mice, effectively correct exacerbated cardiac dysfunctions in eosinophil-deficient ∆dblGATA mice. This study establishes a cardioprotective role of eosinophils in post-MI hearts. Blood eosinophil (EOS) counts may serve as risk factors for human coronary heart diseases. Here the authors show that increased circulating and myocardial EOS after myocardial infarction play a cardioprotective role by reducing cardiomyocyte death, cardiac fibroblast activation and fibrosis, and endothelium activation-mediated inflammatory cell accumulation.
Research on load-bearing optimization of non-circular gear based on asymmetric pressure angles
To improve the load-bearing capacity of non-circular gear, a design method with asymmetric pressure angles was constructed. The method for forming tooth profiles of non-circular gear based on a rack with asymmetric pressure angles was studied, the enveloping motion model of the profile-forming process and the mathematical model for extracting the profile-forming points were analyzed. The correctness of the profile design by using the motion simulation method and the enhancement of tooth root bending strength were verified. To analyze the undercutting phenomena for non-circular gear, a graphical method for identifying undercutting in each tooth profiles of non-circular gear was designed. Finally, a design case with asymmetric pressure angles was used in the high-pressure constant-flux pumps, and the results show that the bearing capacity of the gear pair was significantly improved, and the tooth fracture phenomenon was eliminated.
CircRNA/lncRNA–miRNA–mRNA network and gene landscape in calcific aortic valve disease
Background Calcific aortic valve disease (CAVD) is a common valve disease with an increasing incidence, but no effective drugs as of yet. With the development of sequencing technology, non-coding RNAs have been found to play roles in many diseases as well as CAVD, but no circRNA/lncRNA–miRNA–mRNA interaction axis has been established. Moreover, valve interstitial cells (VICs) and valvular endothelial cells (VECs) play important roles in CAVD, and CAVD differed between leaflet phenotypes and genders. This work aims to explore the mechanism of circRNA/lncRNA–miRNA–mRNA network in CAVD, and perform subgroup analysis on the important characteristics of CAVD, such as key cells, leaflet phenotypes and genders. Results We identified 158 differentially expressed circRNAs (DEcircRNAs), 397 DElncRNAs, 45 DEmiRNAs and 167 DEmRNAs, and constructed a hsa-circ-0073813/hsa-circ-0027587–hsa-miR-525-5p–SPP1/HMOX1/CD28 network in CAVD after qRT-PCR verification. Additionally, 17 differentially expressed genes (DEGs) in VICs, 9 DEGs in VECs, 7 DEGs between different leaflet phenotypes and 24 DEGs between different genders were identified. Enrichment analysis suggested the potentially important pathways in inflammation and fibro-calcification during the pathogenesis of CAVD, and immune cell patterns in CAVD suggest that M0 macrophages and memory B cells memory were significantly increased, and many genes in immune cells were also differently expressed. Conclusions The circRNA/lncRNA–miRNA–mRNA interaction axis constructed in this work and the DEGs identified between different characteristics of CAVD provide a direction for a deeper understanding of CAVD and provide possible diagnostic markers and treatment targets for CAVD in the future.
Innate Lymphoid Cells and Myocardial Infarction
Myocardial infarction results from obstruction of a coronary artery that causes insufficient blood supply to the myocardium and leads to ischemic necrosis. It is one of the most common diseases threatening human health and is characterized by high morbidity and mortality. Atherosclerosis is the pathological basis of myocardial infarction, and its pathogenesis has not been fully elucidated. Innate lymphoid cells (ILCs) are an important part of the human immune system and participate in many processes, including inflammation, metabolism and tissue remodeling, and play an important role in atherosclerosis. However, their specific roles in myocardial infarction are unclear. This review describes the current understanding of the relationship between innate lymphoid cells and myocardial infarction during the acute phase of myocardial infarction, myocardial ischemia-reperfusion injury, and heart repair and regeneration following myocardial infarction. We suggest that this review may provide new potential intervention targets and ideas for treatment and prevention of myocardial infarction.
Sestrin2 Suppresses Classically Activated Macrophages-Mediated Inflammatory Response in Myocardial Infarction through Inhibition of mTORC1 Signaling
Myocardial infarction (MI) triggers an intense inflammatory response that is essential for dead tissue clearance but also detrimental to cardiac repair. Macrophages are active and critical players in the inflammatory response after MI. Understanding the molecular mechanisms by which macrophage-mediated inflammatory response is regulated is important for designing new therapeutic interventions for MI. In the current study, we examined the role of Sestrin2, which is a stress-inducible protein that regulate metabolic homeostasis, in the regulation of inflammatory response of cardiac macrophages after MI. We found that cardiac macrophages upregulated Sestrin2 expression in a mouse MI model. Using a lentiviral transduction system to overexpress Sestrin2 in polarized M1 and M2 macrophages, we revealed that Sestrin2 predominantly functioned on M1 rather than M2 macrophages. Sestrin2 overexpression suppressed inflammatory response of M1 macrophages both and . Furthermore, in the mouse MI model with selective depletion of endogenous macrophages and adoptive transfer of exogenous Sestrin2-overexpressing macrophages, the anti-inflammatory and repair-promoting effect of Sestrin2-overexpressing macrophages was demonstrated. Furthermore, Sestrin2 significantly inhibited mTORC1 signaling in M1 macrophages. Taken together, our study indicates the importance of Sestrin2 for suppression of M1 macrophage-mediated cardiac inflammation after MI.
Two-sample Mendelian randomization to study the causal association between gut microbiota and atherosclerosis
According to some recent observational studies, the gut microbiota influences atherosclerosis via the gut microbiota-artery axis. However, the causal role of the gut microbiota in atherosclerosis remains unclear. Therefore, we used a Mendelian randomization (MR) strategy to try to dissect this causative link. The biggest known genome-wide association study (GWAS) (n = 13,266) from the MiBioGen collaboration was used to provide summary data on the gut microbiota for a two-sample MR research. Data on atherosclerosis were obtained from publicly available GWAS data from the FinnGen consortium, including cerebral atherosclerosis (104 cases and 218,688 controls), coronary atherosclerosis (23,363 cases and 187,840 controls), and peripheral atherosclerosis (6631 cases and 162,201 controls). The causal link between gut microbiota and atherosclerosis was investigated using inverse variance weighting, MR-Egger, weighted median, weighted mode, and simple mode approaches, among which inverse variance weighting was the main research method. Cochran's Q statistic was used to quantify the heterogeneity of instrumental variables (IVs), and the MR Egger intercept test was used to assess the pleiotropy of IVs. Inverse-variance-weighted (IVW) estimation showed that had a protective influence on cerebral atherosclerosis (OR = 0.10, 95% CI: 0.01-0.67, = 0.018), while (OR = 5.39, 95% CI: 1.50-19.37, = 0.010), (OR = 6.87, 95% CI: 1.60-29.49, = 0.010), (OR = 2.88, 95% CI: 1.18-7.05, = 0.021), and (OR = 5.26, 95% CI: 1.28-21.61, = 0.021) had pathogenic effects on cerebral atherosclerosis. For (OR = 0.87, 95% CI: 0.76-0.99, = 0.039), the (OR = 0.89, 95% CI: 0.80-1.00, = 0.048), the (OR = 0.80, 95% CI: 0.69-0.94, = 0.006), and the (OR = 0.87, 95% CI: 0.77-0.98, = 0.023) were protective against coronary atherosclerosis. However, the (OR = 1.12, 95% CI: 1.00-1.24, = 0.049) had a pathogenic effect on coronary atherosclerosis. Finally, (OR = 0.83, 95% CI: 0.69-0.99, = 0.036), (OR = 0.76, 95% CI: 0.61-0.94, = 0.013), (OR = 0.76, 95% CI: 0.60-0.96, = 0.022), and (OR = 0.65, 95% CI: 0.46-0.92, = 0.013), these four microbiota have a protective effect on peripheral atherosclerosis. However, for the (OR = 1.25, 95% CI: 1.01-1.56, = 0.040) and the (OR = 1.22, 95% CI: 1.04-1.42, = 0.016), there is a pathogenic role for peripheral atherosclerosis. No heterogeneity was found for instrumental variables, and no considerable horizontal pleiotropy was observed. We discovered that the presence of probiotics and pathogens in the host is causally associated with atherosclerosis, and atherosclerosis at different sites is causally linked to specific gut microbiota. The specific gut microbiota associated with atherosclerosis identified by Mendelian randomization studies provides precise clinical targets for the treatment of atherosclerosis. In the future, we can further examine the gut microbiota's therapeutic potential for atherosclerosis if we have a better grasp of the causal relationship between it and atherosclerosis.
Kruppel-Like Factor 2-Mediated Suppression of MicroRNA-155 Reduces the Proinflammatory Activation of Macrophages
Recent evidence indicates that significant interactions exist between Kruppel-like factor 2 (KLF2) and microRNAs (miRNAs) in endothelial cells. Because KLF2 is known to exert anti-inflammatory effects and inhibit the pro-inflammatory activation of monocytes, we sought to identify how inflammation-associated miR-155 is regulated by KLF2 in macrophages. Peritoneal macrophages from wild-type (WT) C57Bl/6 mice were transfected with either recombinant adenovirus vector expressing KLF2 (Ad-KLF2) or siRNA targeting KLF2 (KLF2-siRNA) for 24 h-48 h, then stimulated with oxidized low-density lipoproteins (ox-LDL, 50 μg/mL) for 24 h. Quantitative real-time polymerase chain reaction showed that KLF2 markedly reduced the expression of miR-155 in quiescent/ox-LDL-stimulated macrophages. We also found that the increased expression of miR-155, monocyte chemoattractant protein (MCP-1) and interleukin (IL)-6 and the decreased expression of the suppressor of cytokine signaling (SOCS)-1 and IL-10 in ox-LDL-treated macrophages were significantly suppressed by KLF2. Most importantly, over-expression of miR-155 could partly reverse the suppressive effects of KLF2 on the inflammatory response of macrophages. Conversely, the suppression of miR-155 in KLF2 knockdown macrophages significantly overcame the pro-inflammatory properties associated with KLF2 knockdown. Finally, Ad-KLF2 significantly attenuated the diet-induced formation of atherosclerotic lesions in apolipoprotein E-deficient (apoE(-/-)) mice, which was associated with a significantly reduced expression of miR-155 and its relative inflammatory cytokine genes in the aortic arch and in macrophages. KLF2-mediated suppression of miR-155 reduced the inflammatory response of macrophages.
Meshing principle and transmission analysis of a beveloid non-circular gear
To improve the stability and accuracy of non-circular gear transmission, a beveloid non-circular gear transmission scheme was developed to reduce the meshing impact and achieve backlash adjustment. When using the beveloid rack as the medium, the instantaneous contact line of the beveloid non-circular gear pair was shown to be a straight line, and the tooth surface was shown to be a ruled surface based on the transmission relationship between the rack centerline and the non-circular pitch curve. The zero-modification method was employed to develop the beveloid non-circular gear. Further, the generation method for the tooth profile of the modified non-circular gear was reviewed, and a digital solid model was developed for the beveloid non-circular gear. The physical contact simulation method was used to analyze the meshing backlash, and the influence of the axial displacement adjustment on the meshing backlash of the gear pair was obtained. By considering a pair of beveloid elliptic gears as an example, machining and transmission experiments were conducted, with results showing smooth gear-pair meshing and the anticipated backlash adjustment effect.
Single-cell landscape dissecting the transcription and heterogeneity of innate lymphoid cells in ischemic heart
Until now, few articles have revealed the potential roles of innate lymphoid cells (ILCs) in cardiovascular diseases. However, the infiltration of ILC subsets in ischemic myocardium, the roles of ILC subsets in myocardial infarction (MI) and myocardial ischemia-reperfusion injury (MIRI) and the related cellular and molecular mechanisms have not been described with a sufficient level of detail. In the current study, 8-week-old male C57BL/6J mice were divided into three groups: MI, MIRI and sham group. Single-cell sequencing technology was used to perform dimensionality reduction clustering of ILC to analyze the ILC subset landscape at a single-cell resolution, and finally flow cytometry was used to confirm the existence of the new ILC subsets in different disease groups. Five ILC subsets were found, including ILC1, ILC2a, ILC2b, ILCdc and ILCt. It is worth noting that ILCdc, ILC2b and ILCt were identified as new ILC subclusters in the heart. The cellular landscapes of ILCs were revealed and signal pathways were predicted. Furthermore, pseudotime trajectory analysis exhibited different ILC statuses and traced related gene expression in normal and ischemic conditions. In addition, we established a ligand-receptor-transcription factor-target gene regulatory network to disclose cell communications among ILC clusters. Moreover, we further revealed the transcriptional features of the ILCdc and ILC2a subsets. Finally, the existence of ILCdc was confirmed by flow cytometry. Collectively, by characterizing the spectrums of ILC subclusters, our results provide a new blueprint for understanding ILC subclusters' roles in myocardial ischemia diseases and further potential treatment targets.
Oxidized Low Density Lipoprotein Induced Caspase-1 Mediated Pyroptotic Cell Death in Macrophages: Implication in Lesion Instability?
Macrophage death in advanced lesion has been confirmed to play an important role in plaque instability. However, the mechanism underlying lesion macrophage death still remains largely unknown. Immunohistochemistry showed that caspase-1 activated in advanced lesion and co-located with macrophages and TUNEL positive reaction. In in-vitro experiments showed that ox-LDL induced caspase-1 activation and this activation was required for ox-LDL induced macrophages lysis, IL-1β and IL-18 production as well as DNA fragmentation. Mechanism experiments showed that CD36 and NLRP3/caspase-1/pathway involved in ox-LDL induced macrophage pyroptosis. Our study here identified a novel cell death, pyroptosis in ox-LDL induced human macrophage, which may be implicated in lesion macrophages death and play an important role in lesion instability.