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1.
Medicine (Baltimore) ; 102(35): e34717, 2023 Sep 01.
Article in English | MEDLINE | ID: mdl-37657045

ABSTRACT

NUMB has been initially identified as a critical cell fate determinant that modulates cell differentiation via asymmetrical partitioning during mitosis, including tumor cells. However, it remains absent that a systematic assessment of the mechanisms underlying NUMB and its homologous protein NUMBLIKE (NUMBL) involvement in cancer. This study aimed to investigate the prognostic significance for NUMB and NUMBL in pan-cancer. In this study, using the online databases TIMER2.0, gene expression profiling interactive analysis, cBioPortal, the University of ALabama at Birmingham CANcer data analysis Portal, SearchTool for the Retrieval of Interacting Genes/Proteins, and R software, we focused on the relevance between NUMB/NUMBL and oncogenesis, progression, mutation, phosphorylation, function and prognosis. This study demonstrated that abnormal expression of NUMB and NUMBL were found to be significantly associated with clinicopathologic stages and the prognosis of survival. Besides, genetic alternations of NUMB and NUMBL focused on uterine corpus endometrial carcinoma, and higher genetic mutations of NUMBL were correlated with more prolonged overall survival and disease-free survival in different cancers. Moreover, S438 locus of NUMB peptide fragment was frequently phosphorylated in 4 cancer types and relevant to its phosphorylation sites. Furthermore, endocytosis processing and neurogenesis regulation were involved in the functional mechanisms of NUMB and NUMBL separately. Additionally, the pathway enrichment suggested that NUMB was implicated in Hippo, Neurotrophin, Thyroid hormone, and FoxO pathways, while MAPK, Hippo, Rap1, mTOR, and Notch pathways were related to the functions of NUMBL. This study highlights the predictive roles of NUMB and NUMBL in pan-cancer, suggesting NUMB and NUMBL might be served as potential biomarkers for diagnosis and prognosis in various malignant tumors.


Subject(s)
Carcinogenesis , Carcinoma, Endometrioid , Humans , Female , Prognosis , Cell Differentiation , Cell Nucleus Division , Intracellular Signaling Peptides and Proteins
2.
Cell Death Discov ; 9(1): 279, 2023 Aug 01.
Article in English | MEDLINE | ID: mdl-37528096

ABSTRACT

To date, there is no effective therapy for pathological cardiac hypertrophy, which can ultimately lead to heart failure. Bellidifolin (BEL) is an active xanthone component of Gentianella acuta (G. acuta) with a protective function for the heart. However, the role and mechanism of BEL action in cardiac hypertrophy remain unknown. In this study, the mouse model of cardiac hypertrophy was established by isoprenaline (ISO) induction with or without BEL treatment. The results showed that BEL alleviated cardiac dysfunction and pathological changes induced by ISO in the mice. The expression of cardiac hypertrophy marker genes, including ANP, BNP, and ß-MHC, were inhibited by BEL both in mice and in H9C2 cells. Furthermore, BEL repressed the epigenetic regulator bromodomain-containing protein 4 (BRD4) to reduce the ISO-induced acetylation of H3K122 and phosphorylation of RNA Pol II. The Nox4/ROS/ADAM17 signalling pathway was also inhibited by BEL in a BRD4 dependent manner. Thus, BEL alleviated cardiac hypertrophy and cardiac dysfunction via the BRD4/Nox4/ROS axes during ISO-induced cardiac hypertrophy. These findings clarify the function and molecular mechanism of BEL action in the therapeutic intervention of cardiac hypertrophy.

3.
Int J Biol Macromol ; 251: 126327, 2023 Aug 12.
Article in English | MEDLINE | ID: mdl-37579907

ABSTRACT

Porcine deltacoronavirus (PDCoV) is an emerging swine enteropathogenic coronavirus that mainly threatens newborn piglets and poses a potential broad cross-species transmission risk. The antigenic epitopes of PDCoV are currently unidentified, and no information about T cell epitopes is available. Here, T-cell epitopes of PDCoV structural proteins were predicted using computational methods. 17 epitope peptides were synthesized and then screened using ELIspot, intracellular cytokine staining (ICS), and RT-qPCR detection of IFN-γ mRNA to evaluate their ability to elicit interferon-gamma (IFN-γ) responses in peripheral blood mononuclear cells (PBMCs) from PDCoV-challenged pigs. Five peptides (M1, M2, M3, N6, and S4) elicited high levels of IFN-γ and were investigated further as potential T-cell epitope candidates. All five peptides were cytotoxic T lymphocyte (CTL) epitopes, and two peptides (M3, N6) were recognized simultaneously by CD8 + and CD4 + T cells. A multi-epitope peptide combining the five epitopes (designated "5T") was synthesized and its immune response and protection efficacy was evaluated in a piglet model. ELISpot assay results indicated that 5T induces robust epitope-specific cellular immune responses. Four epitopes (M1, M2, N6, S4) elicited IFN-γ responses in 5T-vaccinated piglets. No obvious protection efficacy was detected in piglets vaccinated with 5T alone. Our results provide valuable information concerning PDCoV-related antigenic epitopes and will be useful in the design of epitope-based vaccines.

4.
Biomed Pharmacother ; 154: 113564, 2022 Oct.
Article in English | MEDLINE | ID: mdl-35988427

ABSTRACT

Cardiac remodelling mainly manifests as excessive myocardial hypertrophy and fibrosis, which are associated with heart failure. Gentianella acuta (G. acuta) is reportedly effective in cardiac protection; however, the mechanism by which it protects against cardiac remodelling is not fully understood. Here, we discuss the effects and mechanisms of G. acuta in transverse aortic constriction (TAC)-induced cardiac remodelling in rats. Cardiac function was analysed using echocardiography and electrocardiography. Haematoxylin and eosin, Masson's trichrome, and wheat germ agglutinin staining were used to observe pathophysiological changes. Additionally, real-time quantitative reverse transcription polymerase chain reaction and western blotting were used to measure protein levels and mRNA levels of genes related to myocardial hypertrophy and fibrosis. Immunofluorescence double staining was used to investigate the co-expression of endothelial and interstitial markers. Western blotting was used to estimate the expression and phosphorylation levels of the regulatory proteins involved in autophagy and endothelial-mesenchymal transition (EndMT). The results showed that G. acuta alleviated cardiac dysfunction and remodelling. The elevated levels of myocardial hypertrophy and fibrosis markers, induced by TAC, decreased significantly after G. acuta intervention. G. acuta decreased the expression of LC3 II and Beclin1, and increased p62 expression. G. acuta upregulated the expression of CD31 and vascular endothelial-cadherin, and prevented the expression of α-smooth muscle actin and vimentin. Furthermore, G. acuta inhibited the PI3K/Akt/FOXO1/3a pathway and activated the Notch signalling. These findings demonstrated that G. acuta has cardioprotective effects, such as alleviating myocardial fibrosis, inhibiting hypertrophy, reducing autophagy, and blocking EndMT by regulating the PI3K/Akt/FOXO1/3a and Notch signalling pathways.


Subject(s)
Aortic Valve Stenosis , Gentianella , Animals , Aortic Valve Stenosis/metabolism , Cardiomegaly/metabolism , Fibrosis , Myocardium/pathology , Nerve Tissue Proteins/metabolism , Phosphatidylinositol 3-Kinases/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Rats , Ventricular Remodeling
5.
Pharmazie ; 77(5): 137-140, 2022 05 01.
Article in English | MEDLINE | ID: mdl-35655382

ABSTRACT

Cardiomyocyte autophagy is closely related to myocardial infarction and hypertrophy. To study the molecular mechanism of autophagy is helpful for the prevention and treatment of these diseases. As a cell surface receptor, the function of ITGB1 gene in cardiomyocyte autophagy is not clear. The purpose of this research was to investigate the function and molecular mechanism of ITGB1 on autophagy. The autophagy-related marker proteins and signaling molecules were detected using western blot with knockdown and overexpression of ITGB1 in H9C2 cells. The results suggested that ITGB1 could inhibit autophagy and the mTORC2/Akt pathway molecules. To further investigate whether the effect of ITGB1 on autophagy might affect myocardial hypertrophy, we constructed AngII induced H9C2 cells and TAC induced rats models. The results showed that ITGB1 inhibited myocardial hypertrophy in both H9C2 cells and heart tissues of disease model. These data highlight the regulation mechanism on autophagy by ITGB1 and the potential usefulness of the gene as a potential target for preventing heart disease.


Subject(s)
Autophagy , Proto-Oncogene Proteins c-akt , Animals , Cardiomegaly/metabolism , Mechanistic Target of Rapamycin Complex 2/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Rats , Signal Transduction
6.
Article in English | MEDLINE | ID: mdl-35586685

ABSTRACT

Myocardial fibrosis is the main morphological change of ventricular remodelling caused by cardiovascular diseases, mainly manifested due to the excessive production of collagen proteins. SRY-related high mobility group-box gene 9 (SOX9) is a new target regulating myocardial fibrosis. Bellidifolin (BEL), the active component of G. acuta, can prevent heart damage. However, it is unclear whether BEL can regulate SOX9 to alleviate myocardial fibrosis. The mice were subjected to isoproterenol (ISO) to establish myocardial fibrosis, and human myocardial fibroblasts (HCFs) were activated by TGF-ß1 in the present study. The pathological changes of cardiac tissue were observed by HE staining. Masson staining was applied to reveal the collagen deposition in the heart. The measurement for expression of fibrosis-related proteins, SOX9, and TGF-ß1 signalling molecules adopted Western blot and immunohistochemistry. The effects of BEL on HCFs, activity were detected by CCK-8. The result showed that BEL did not affect cell viability. And, the data indicated that BEL inhibited the elevations in α-SMA, Collagen I, and Collagen III by decreasing SOX9 expression. Additionally, SOX9 suppression by siRNA downregulated the TGF-ß1 expression and prevented Smad3 phosphorylation, as supported by reducing the expression of α-SMA, Collagen I, and Collagen III. In vivo study verified that BEL ameliorated myocardial fibrosis by inhibiting SOX9. Therefore, BEL inhibited SOX9 to block TGF-ß1 signalling activation to ameliorate myocardial fibrosis.

7.
Viruses ; 14(3)2022 02 28.
Article in English | MEDLINE | ID: mdl-35336903

ABSTRACT

(1) Background: Porcine deltacoronavirus (PDCoV) is a newly emerged enteric virus affecting pig breeding industries worldwide, and its pathogenic mechanism remains unclear. (2) Methods: In this study, we preliminarily identified the endocytic pathway of PDCoV in PK-15 cells, using six chemical inhibitors (targeting clathrin-mediated endocytosis, caveolae-mediated endocytosis, macropinocytosis pathway and endosomal acidification), overexpression of dominant-negative (DN) mutants to treat PK-15 cells and proteins knockdown. (3) Results: The results revealed that PDCoV entry was not affected after treatment with chlorpromazine (CPZ), 5-(N-ethyl-N-isopropyl) amiloride (EIPA)or ammonium chloride (NH4Cl), indicating that the entry of PDCoV into PK-15 cells were clathrin-, micropinocytosis-, PH-independent endocytosis. Conversely, PDCoV infection was sensitive to nystatin, dynasore and methyl-ß-cyclodextrin (MßCD) with reduced PDCoV internalization, indicating that entry of PDCoV into PK-15 cells was caveolae-mediated endocytosis that required dynamin and cholesterol; indirect immunofluorescence and shRNA interference further validated these results. (4) Conclusions: In conclusion, PDCoV entry into PK-15 cells depends on caveolae-mediated endocytosis, which requires cholesterol and dynamin. Our finding is the first initial identification of the endocytic pathway of PDCoV in PK-15 cells, providing a theoretical basis for an in-depth understanding of the pathogenic mechanism of PDCoV and the design of new antiviral targets.


Subject(s)
Caveolae , Virus Internalization , Animals , Caveolae/metabolism , Cell Line , Cholesterol/metabolism , Clathrin/metabolism , Deltacoronavirus , Dynamins/metabolism , Endocytosis , Swine
8.
IEEE Trans Pattern Anal Mach Intell ; 44(11): 8151-8166, 2022 11.
Article in English | MEDLINE | ID: mdl-34351854

ABSTRACT

Modern methods for counting people in crowded scenes rely on deep networks to estimate people densities in individual images. As such, only very few take advantage of temporal consistency in video sequences, and those that do only impose weak smoothness constraints across consecutive frames. In this paper, we advocate estimating people flows across image locations between consecutive images and inferring the people densities from these flows instead of directly regressing them. This enables us to impose much stronger constraints encoding the conservation of the number of people. As a result, it significantly boosts performance without requiring a more complex architecture. Furthermore, it allows us to exploit the correlation between people flow and optical flow to further improve the results. We also show that leveraging people conservation constraints in both a spatial and temporal manner makes it possible to train a deep crowd counting model in an active learning setting with much fewer annotations. This significantly reduces the annotation cost while still leading to similar performance to the full supervision case.


Subject(s)
Algorithms , Crowding , Humans
9.
Vet Microbiol ; 265: 109316, 2022 Feb.
Article in English | MEDLINE | ID: mdl-34954542

ABSTRACT

Porcine deltacoronavirus (PDCoV) is highly pathogenic to piglets, and no specific drugs or vaccines are available for the prevention and treatment of PDCoV infection, the need for antiviral therapies is pressing. HSP90 inhibitors have potent inhibitory effects against the replication of numerous viruses, hence we evaluated three HSP90 inhibitors, 17-AAG, VER-82576, and KW-2478, for their effects on PDCoV infection in vitro. We evaluated their effectivenesses at suppressing PDCoV by qRT-PCR, western blot, and TCID50 assay, and found that 17-AAG and VER-82576 inhibited PDCoV at the early stage of replication, while KW-2478 showed no significant antiviral activity at any stage of infection. These results indicated that the PDCoV-inhibitory effects of 17-AAG and VER-82576 might be exerted by targeting host cell factor HSP90AB1 but not HSP90AA1. Further study showed that HSP90AB1 mRNA and protein levels were not significantly different in 17-AAG and VER-82576-treated cells versus control cells. 17-AAG and VER-82576 were also evaluated for their effects on the expressions of TNF-α, IL-6, and IL-12, which are PDCoV-induced proinflammatory cytokines. We found that both 17-AAG and VER-82576 inhibited the expressions of TNF-α, IL-6, and IL-12 to varying degrees, but in a dose dependent manner. From our data we can conclude that the HSP90 inhibitors 17-AAG and VER-82576 are promising candidates for the treatment of PDCoV infection.


Subject(s)
Coronavirus Infections , Swine Diseases , Animals , Benzoquinones , Coronavirus Infections/drug therapy , Coronavirus Infections/pathology , Coronavirus Infections/veterinary , Deltacoronavirus , Lactams, Macrocyclic/pharmacology , Lactams, Macrocyclic/therapeutic use , Swine , Swine Diseases/drug therapy
10.
Biomed Pharmacother ; 143: 112178, 2021 Nov.
Article in English | MEDLINE | ID: mdl-34649308

ABSTRACT

Modified citrus pectin (MCP) is a specific inhibitor of galectin-3 (Gal-3) that is regarded as a new biomarker of cardiac hypertrophy, but its effect is unclear. The aim of this study is to investigate the role and mechanism of MCP in isoproterenol (ISO)-induced cardiac hypertrophy. Rats were injected with ISO to induce cardiac hypertrophy and treated with MCP. Cardiac function was detected by ECG and echocardiography. Pathomorphological changes were evaluated by the haematoxylin eosin (H&E) and wheat germ agglutinin (WGA) staining. The hypertrophy-related genes for atrial natriuretic peptide (ANP), brain natriuretic peptide (BNP), and ß-myosin heavy chain (ß-MHC), and the associated signal molecules were analysed by qRT-PCR and western blotting. The results show that MCP prevented cardiac hypertrophy and ameliorated cardiac dysfunction and structural disorder. MCP also decreased the levels of ANP, BNP, and ß-MHC and inhibited the expression of Gal-3 and Toll-like receptor 4 (TLR4). Additionally, MCP blocked the phosphorylation of Janus kinase 2 (JAK2) and signal transducer and activator of transcription 3 (STAT3), but it promoted the phosphorylation of p38. Thus, MCP prevented ISO-induced cardiac hypertrophy by activating p38 signalling and inhibiting the Gal-3/TLR4/JAK2/STAT3 pathway.


Subject(s)
Cardiomegaly/drug therapy , Cardiovascular Agents/pharmacology , Janus Kinase 2/metabolism , Myocytes, Cardiac/drug effects , Pectins/pharmacology , STAT3 Transcription Factor/metabolism , Toll-Like Receptor 4/metabolism , p38 Mitogen-Activated Protein Kinases/metabolism , Animals , Atrial Natriuretic Factor/genetics , Atrial Natriuretic Factor/metabolism , Cardiomegaly/chemically induced , Cardiomegaly/enzymology , Cardiomegaly/physiopathology , Disease Models, Animal , Galectin 3/metabolism , Isoproterenol , Male , Myocytes, Cardiac/enzymology , Myocytes, Cardiac/pathology , Myosin Heavy Chains/genetics , Myosin Heavy Chains/metabolism , Natriuretic Peptide, Brain/genetics , Natriuretic Peptide, Brain/metabolism , Phosphorylation , Rats, Wistar , Signal Transduction , Ventricular Function, Left/drug effects , Ventricular Remodeling/drug effects
11.
J Agric Food Chem ; 69(26): 7313-7323, 2021 Jul 07.
Article in English | MEDLINE | ID: mdl-34165302

ABSTRACT

A biocontrol method plays an important role in weed management. In this study, we aimed to clarify the phytotoxicity of the mycotoxin patulin (PAT) and reveal its mode of action as a new natural photosystem II (PSII) inhibitor. Phytotoxicity test showed that PAT has herbicidal activity and causes significant leaf lesions on Ageratina adenophora. Under a half-inhibition concentration I50 (2.24 µM), the observed significant decrease in oxygen evolution rate and the increase in the J-step of the chlorophyll fluorescence rise OJIP curve indicated that PAT strongly reduces photosynthetic efficiency by blocking electron transport from the primary to secondary plastoquinone acceptors (QA to QB) of PSII. Molecular modeling of PAT docking to the A. adenophora D1 protein suggested that PAT bounds to the QB site by forming hydrogen bonds to histidine 252 in the D1 protein. It is proposed that PAT is a new natural PSII inhibitor and has the potential to be developed into a bioherbicide or used as a template scaffold for discovering novel derivatives with more potent herbicidal activity.


Subject(s)
Patulin , Photosystem II Protein Complex , Chlorophyll , Electron Transport , Patulin/toxicity , Photosynthesis , Photosystem II Protein Complex/metabolism
12.
Phys Rev Lett ; 125(13): 133401, 2020 Sep 25.
Article in English | MEDLINE | ID: mdl-33034470

ABSTRACT

We investigate the metastable repulsive branch of a mobile impurity coupled to a degenerate Fermi gas via short-range interactions. We show that the quasiparticle lifetime of this repulsive Fermi polaron can be experimentally probed by driving Rabi oscillations between weakly and strongly interacting impurity states. Using a time-dependent variational approach, we find that we can accurately model the impurity Rabi oscillations that were recently measured for repulsive Fermi polarons in both two and three dimensions. Crucially, our theoretical description does not include relaxation processes to the lower-lying attractive branch. Thus, the theory-experiment agreement demonstrates that the quasiparticle lifetime is dominated by many-body dephasing within the upper repulsive branch rather than by relaxation from the upper branch itself. Our findings shed light on recent experimental observations of persistent repulsive correlations, and have important consequences for the nature and stability of the strongly repulsive Fermi gas.

13.
Phys Rev Lett ; 125(6): 065301, 2020 Aug 07.
Article in English | MEDLINE | ID: mdl-32845677

ABSTRACT

We investigate the radio-frequency spectroscopy of impurities interacting with a quantum gas at finite temperature. In the limit of a single impurity, we show using Fermi's golden rule that introducing (or injecting) an impurity into the medium is equivalent to ejecting an impurity that is initially interacting with the medium, since the "injection" and "ejection" spectral responses are simply related to each other by an exponential function of frequency. Thus, the full spectral information for the quantum impurity is contained in the injection spectral response, which can be determined using a range of theoretical methods, including variational approaches. We use this property to compute the finite-temperature equation of state and Tan contact of the Fermi polaron. Our results for the contact of a mobile impurity are in excellent agreement with recent experiments and we find that the finite-temperature behavior is qualitatively different compared to the case of infinite impurity mass.

14.
Biosci Biotechnol Biochem ; 84(11): 2253-2263, 2020 Nov.
Article in English | MEDLINE | ID: mdl-32787513

ABSTRACT

The study was aimed to investigate the effect of alpha-lipoic acid (ALA) on human umbilical vein endothelial cells (HUVECs) injury induced by hydrogen peroxide (H2O2) and to explore its possible mechanisms. We established the H2O2-induced HUVECs injury model and the ALA treatment groups in which HUVECs were co-incubated with H2O2 (250 µmol/L) and different final concentrations of ALA (100,200,400 µmol/L) for 48 h. Cell survival rate assay and LDH activity assay were carried out. The levels of related proteins were performed by Western Blot. We observed that H2O2 administration resulted in an increase in the LDH activity and a decrease in cell survival rate. The expression levels of Nox4, Bax, NF-κB p65, Caspase-9, Caspase-3, iNOS, VCAM-1 and ICAM-1 were up-regulated, while the expression level of Bcl-2 was down-regulated. All these factors were significantly improved by ALA treatment. In brief, ALA treatment ameliorates H2O2-induced HUVECs damage by inhibiting inflammation and oxidative stress.


Subject(s)
Human Umbilical Vein Endothelial Cells/cytology , Human Umbilical Vein Endothelial Cells/drug effects , Hydrogen Peroxide/adverse effects , Oxidative Stress/drug effects , Thioctic Acid/pharmacology , Apoptosis/drug effects , Cytoprotection/drug effects , Down-Regulation/drug effects , Human Umbilical Vein Endothelial Cells/metabolism , Humans , Inflammation/pathology , L-Lactate Dehydrogenase/metabolism , NADPH Oxidase 4/metabolism , NF-kappa B/metabolism , Signal Transduction/drug effects
15.
J Biomol Struct Dyn ; 38(17): 5081-5094, 2020 Oct.
Article in English | MEDLINE | ID: mdl-31755361

ABSTRACT

It is well known that the interactions of p53 with murine double minute 2 and murine double minute X, namely MDM2 and MDMX, have been significant targets of efficient anti-cancer drug design. In this study, molecular dynamics (MD) simulations, principal component (PC) analysis and binding free energy calculations are combined to recognize binding selectivity of three ligands to MDM2 and MDMX. The binding free energies were estimated by using molecular mechanics generalized Born surface area (MM-GBSA) method and the obtained results display that the increase in the binding enthalpy of three ligands to MDM2 relative to MDMX mainly drives the binding selectivity of them toward MDM2 and MDMX. The information obtained from PC analysis shows that the associations of ligands exert important impacts on internal dynamics of MDM2 and MDMX. Meanwhile, the calculations of residue-based free energy decomposition not only identify the hot interaction spots of ligands with MDM2 and MDMX, but also show the residues (L54, M53), (Y67, Y66), (V93, V92), (H96, P95), (I99, I98) and (Y100, Y99) in (MDM2, MDMX) are responsible for most contributions to the binding selectivity of three ligands toward MDM2 and MDMX. It is believed that this work can provide useful information for design of highly selective and dual inhibitors targeting MDM2 and MDMX.Communicated by Ramaswamy H. Sarma.


Subject(s)
Molecular Dynamics Simulation , Proto-Oncogene Proteins c-mdm2 , Animals , Cell Cycle Proteins , Ligands , Mice , Nuclear Proteins/metabolism , Protein Binding , Proto-Oncogene Proteins/metabolism , Proto-Oncogene Proteins c-mdm2/metabolism , Tumor Suppressor Protein p53/metabolism
16.
Phys Rev Lett ; 122(20): 205301, 2019 May 24.
Article in English | MEDLINE | ID: mdl-31172772

ABSTRACT

We present a general variational principle for the dynamics of impurity particles immersed in a quantum-mechanical medium. By working within the Heisenberg picture and constructing approximate time-dependent impurity operators, we can take the medium to be in any mixed state, such as a thermal state. Our variational method is consistent with all conservation laws and, in certain cases, it is equivalent to a finite-temperature Green's function approach. As a demonstration of our method, we consider the dynamics of heavy impurities that have suddenly been introduced into a Fermi gas at finite temperature. Using approximate time-dependent impurity operators involving only one particle-hole excitation of the Fermi sea, we find that we can successfully model the results of recent Ramsey interference experiments on ^{40}K atoms in a ^{6}Li Fermi gas. We also show that our approximation agrees well with the exact solution for the Ramsey response of a fixed impurity at finite temperature. Our approach paves the way for the investigation of impurities with dynamical degrees of freedom in arbitrary quantum-mechanical mediums.

17.
Cell Death Dis ; 9(10): 999, 2018 09 24.
Article in English | MEDLINE | ID: mdl-30250269

ABSTRACT

The establishment of functional neuronal connectivity is dependent on the neuronal migration and the accurate positioning of neurons in the developing brain. Abnormal neuronal migration can trigger neuronal maturation defects and apoptosis. However, many genetic bases remain unclear in neuronal migration disorders during brain development. In this study, we reported that MARVELD1-defected mice displayed motor and cognitive dysfunction resulting from aberrant neuronal migration during brain development. The laminar organization of the cerebral cortex and cerebellum in MARVELD1 knockout (KO) mice is disrupted, indicating impaired radial neuronal migration. Furthermore, we used the cerebellum as a model to explore the radial neuronal migration processes, and the results demonstrated that the proper neuronal migration depended on MARVELD1 expression in glial cells of the developing brain. MARVELD1 suppressed the expression of ITGB1 and FAK Tyr397 phosphorylation in glia-dependent manner. The inhibition of the MARVELD1/ITGB1/FAK signalling pathway in MARVELD1 KO mice could reverse the defects in neuronal migration in vitro. Our findings revealed that MARVELD1 regulated neuronal migration by mediating the formation of glial fibres and ITGB1/FAK signalling pathway. The depletion of MARVELD1 during mouse brain development led to the abnormity of motor and cognition functions.


Subject(s)
Cell Movement/physiology , Cerebellar Cortex/growth & development , Cognitive Dysfunction/metabolism , Membrane Proteins/metabolism , Microtubule-Associated Proteins/metabolism , Movement/physiology , Neuroglia/metabolism , Neurons/metabolism , Animals , Cerebellar Cortex/metabolism , Exercise Test , Focal Adhesion Kinase 1/metabolism , Gene Knockout Techniques , Integrin beta1/metabolism , Membrane Proteins/genetics , Mice , Mice, Inbred C57BL , Mice, Knockout , Microtubule-Associated Proteins/genetics , Neurogenesis/physiology , Phosphorylation , Purkinje Cells/metabolism
18.
Peptides ; 106: 96-101, 2018 08.
Article in English | MEDLINE | ID: mdl-30016700

ABSTRACT

For clinical use, it is essential to develop potent endomorphin (EM) analogs with reduced antinociceptive tolerance. In the present study, the antinociceptive activities and tolerance development of four potent EM-1 analogs with C-terminal oligoarginine-conjugation was evaluated and compared in the radiant heat paw withdrawal test. Following intracerebroventricular (i.c.v.) administration, all analogs 1-4 produced potent and prolonged antinociceptive effects. Notably, analogs 2 and 4 with the introduction of D-Ala in position 2 exhibited relatively higher analgesic potencies than those of analogs 1 and 3 with ß-Pro substitution, consistent with their µ-opioid binding characteristic. In addition, at a dose of 50 µmol/kg, endomorphin-1 (EM-1) failed to produce any significant antinociceptive activity after peripheral administration, whereas analogs 1-4 induced potent antinociceptive effects with an increased duration of action. Herein, our results indicated the development of antinociceptive tolerance to EM-1 and morphine at the supraspinal level on day 7. By contrast, analogs 1-4 decreased the antinociceptive tolerance. Furthermore, subcutaneous (s.c.) administration of morphine at 50 µmol/kg also developed the antinociceptive tolerance, whereas the extent of tolerance developed to analogs 1-4 was largely reduced. Especially, analog 4 exhibited non-tolerance-forming antinociception after peripheral administration. The present investigation gave the evidence that C-terminal conjugation of EM-1 with oligoarginine vector will facilitate the development of novel opioid analgesics with reduced opioid tolerance.


Subject(s)
Analgesics, Opioid/pharmacology , Analgesics/pharmacology , Arginine/chemistry , Drug Tolerance , Oligopeptides/pharmacology , Animals , Hindlimb/drug effects , Hot Temperature/adverse effects , Male , Mice , Models, Animal , Oligopeptides/chemical synthesis , Oligopeptides/chemistry , Pain/prevention & control , Receptors, Opioid, mu/drug effects
19.
J Cell Physiol ; 233(3): 2257-2269, 2018 Mar.
Article in English | MEDLINE | ID: mdl-28708243

ABSTRACT

The placenta is a remarkable organ, it serves as the interface between the mother and the fetus. Proper invasion of trophoblast cells is required for a successful pregnancy. Previous studies have found that the adhesion molecule integrin ß4 plays important roles during trophoblast cell invasion. Here, we found that the overall birth rate of the MARVELD1 knockout mouse is much lower than that of the wild-type mouse (p < 0.001). In E18.5 MARVELD1 knockout mice, we observed an over-invasion of trophoblast cells, and indeed, the pregnant mice had a partial placenta accreta phenotype. The HTR8/SVneo cell line was used as an in vitro model to elucidate the underlying mechanisms of MARVELD1-mediated trophoblast invasion. We detected a diminished expression of integrin ß4 upon the downregulation of MARVELD1 and enhanced migrate and invasive abilities of trophoblast cells both in vivo and in vitro. The integrin ß4 rescue assay also supported the results. In conclusion, this study found that MARVELD1 mediated the invasion of trophoblast cells via regulating the expression of integrin ß4 during placenta development.


Subject(s)
Cell Movement , Integrin beta4/metabolism , Membrane Proteins/deficiency , Microtubule-Associated Proteins/deficiency , Placenta Accreta/metabolism , Trophoblasts/metabolism , Animals , Cell Adhesion , Cell Line, Tumor , Disease Models, Animal , Female , Gene Expression Regulation , Genetic Predisposition to Disease , Humans , Integrin beta4/genetics , Membrane Proteins/genetics , Membrane Proteins/metabolism , Mice , Mice, Inbred C57BL , Mice, Knockout , Microtubule-Associated Proteins/genetics , Microtubule-Associated Proteins/metabolism , NIH 3T3 Cells , Phenotype , Placenta Accreta/genetics , Placenta Accreta/pathology , Pregnancy , Promoter Regions, Genetic , Signal Transduction , Trophoblasts/pathology
20.
Materials (Basel) ; 10(7)2017 Jul 15.
Article in English | MEDLINE | ID: mdl-28773167

ABSTRACT

Topological materials have attracted considerable experimental and theoretical attention. They exhibit strong spin-orbit coupling both in the band structure (intrinsic) and in the impurity potentials (extrinsic), although the latter is often neglected. In this work, we discuss weak localization and antilocalization of massless Dirac fermions in topological insulators and massive Dirac fermions in Weyl semimetal thin films, taking into account both intrinsic and extrinsic spin-orbit interactions. The physics is governed by the complex interplay of the chiral spin texture, quasiparticle mass, and scalar and spin-orbit scattering. We demonstrate that terms linear in the extrinsic spin-orbit scattering are generally present in the Bloch and momentum relaxation times in all topological materials, and the correction to the diffusion constant is linear in the strength of the extrinsic spin-orbit. In topological insulators, which have zero quasiparticle mass, the terms linear in the impurity spin-orbit coupling lead to an observable density dependence in the weak antilocalization correction. They produce substantial qualitative modifications to the magnetoconductivity, differing greatly from the conventional Hikami-Larkin-Nagaoka formula traditionally used in experimental fits, which predicts a crossover from weak localization to antilocalization as a function of the extrinsic spin-orbit strength. In contrast, our analysis reveals that topological insulators always exhibit weak antilocalization. In Weyl semimetal thin films having intermediate to large values of the quasiparticle mass, we show that extrinsic spin-orbit scattering strongly affects the boundary of the weak localization to antilocalization transition. We produce a complete phase diagram for this transition as a function of the mass and spin-orbit scattering strength. Throughout the paper, we discuss implications for experimental work, and, at the end, we provide a brief comparison with transition metal dichalcogenides.

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