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1.
Yi Chuan ; 45(2): 165-175, 2023 Feb 20.
Article in English | MEDLINE | ID: mdl-36927663

ABSTRACT

The currently widely used CRISPR-Cas9 genome editing technology enables the editing of target genes (knock-out or knock-in) with high accuracy and efficiency. Guided by the small guide RNA, the Cas9 nuclease induces a DNA double-strand break at the targeted genomic locus. The DNA double-strand break can be repaired by the homology-directed repair pathway in the presence of a repair template. With the repair template containing the coding sequence of a fluorescent tag, the targeted gene can be inserted with the sequence of a fluorescent tag at the designed position. The genome editing mediated labeling of endogenous proteins with fluorescent tags avoids the potential artifacts caused by gene overexpression and substantially improves the reproductivity of imaging experiments. This protocol focuses on creating mammalian cell lines with endogenous proteins tagged with fluorescent proteins or self-labeling protein tags using CRISPR-Cas9 genome editing.


Subject(s)
CRISPR-Cas Systems , Gene Editing , Animals , Gene Editing/methods , CRISPR-Associated Protein 9/genetics , Recombinational DNA Repair , DNA , Mammals/genetics
2.
Cell Discov ; 9(1): 18, 2023 Feb 13.
Article in English | MEDLINE | ID: mdl-36781849

ABSTRACT

HER2 belongs to the human epidermal growth factor receptor tyrosine kinase family. Its overexpression or hyperactivation is a leading cause for multiple types of cancers. HER2 functions mainly through dimerization with other family members, such as EGFR. However, the molecular details for heterodimer assembly have not been completely understood. Here, we report cryo-EM structures of the EGF- and epiregulin-bound EGFR/HER2 ectodomain complexes at resolutions of 3.3 Å and 4.5 Å, respectively. Together with the functional analyses, we demonstrate that only the dimerization arm of HER2, but not that of EGFR, is essential for their heterodimer formation and signal transduction. Moreover, we analyze the differential membrane dynamics and transient interactions of endogenous EGFR and HER2 molecules in genome-edited cells using single-molecule live-cell imaging. Furthermore, we show that the interaction with HER2 could allow EGFR to resist endocytosis. Together, this work deepens our understanding of the unique structural properties and dynamics of the EGFR/HER2 complex.

3.
Sensors (Basel) ; 22(6)2022 Mar 19.
Article in English | MEDLINE | ID: mdl-35336553

ABSTRACT

Detection of bacterial pathogens is significant in the fields of food safety, medicine, and public health, just to name a few. If bacterial pathogens are not properly identified and treated promptly, they can lead to morbidity and mortality, also possibly contribute to antimicrobial resistance. Current bacterial detection methodologies rely solely on laboratory-based techniques, which are limited by long turnaround detection times, expensive costs, and risks of inadequate accuracy; also, the work requires trained specialists. Here, we describe a cost-effective and portable 3D-printed electrochemical biosensor that facilitates rapid detection of certain Escherichia coli (E. coli) strains (DH5α, BL21, TOP10, and JM109) within 15 min using 500 µL of sample, and costs only USD 2.50 per test. The sensor displayed an excellent limit of detection (LOD) of 53 cfu, limit of quantification (LOQ) of 270 cfu, and showed cross-reactivity with strains BL21 and JM109 due to shared epitopes. This advantageous diagnostic device is a strong candidate for frequent testing at point of care; it also has application in various fields and industries where pathogen detection is of interest.


Subject(s)
Biosensing Techniques , Escherichia coli , Bacteria , Biosensing Techniques/methods , Limit of Detection , Printing, Three-Dimensional
4.
Dev Cell ; 56(12): 1786-1803.e9, 2021 06 21.
Article in English | MEDLINE | ID: mdl-34129835

ABSTRACT

Nuclear envelope assembly during late mitosis includes rapid formation of several thousand complete nuclear pore complexes (NPCs). This efficient use of NPC components (nucleoporins or "NUPs") is essential for ensuring immediate nucleocytoplasmic communication in each daughter cell. We show that octameric subassemblies of outer and inner nuclear pore rings remain intact in the mitotic endoplasmic reticulum (ER) after NPC disassembly during prophase. These "inherited" subassemblies then incorporate into NPCs during post-mitotic pore formation. We further show that the stable subassemblies persist through multiple rounds of cell division and the accompanying rounds of NPC mitotic disassembly and post-mitotic assembly. De novo formation of NPCs from newly synthesized NUPs during interphase will then have a distinct initiation mechanism. We postulate that a yet-to-be-identified modification marks and "immortalizes" one or more components of the specific octameric outer and inner ring subcomplexes that then template post-mitotic NPC assembly during subsequent cell cycles.


Subject(s)
Cell Nucleus/genetics , Mitosis/genetics , Nuclear Pore Complex Proteins/genetics , Nuclear Pore/genetics , Cell Cycle/genetics , Endoplasmic Reticulum/genetics , Humans , Interphase/genetics , Nuclear Envelope/genetics , Nuclear Pore Complex Proteins/biosynthesis
5.
Cell ; 184(13): 3528-3541.e12, 2021 06 24.
Article in English | MEDLINE | ID: mdl-33984278

ABSTRACT

Nucleotide-binding, leucine-rich repeat receptors (NLRs) are major immune receptors in plants and animals. Upon activation, the Arabidopsis NLR protein ZAR1 forms a pentameric resistosome in vitro and triggers immune responses and cell death in plants. In this study, we employed single-molecule imaging to show that the activated ZAR1 protein can form pentameric complexes in the plasma membrane. The ZAR1 resistosome displayed ion channel activity in Xenopus oocytes in a manner dependent on a conserved acidic residue Glu11 situated in the channel pore. Pre-assembled ZAR1 resistosome was readily incorporated into planar lipid-bilayers and displayed calcium-permeable cation-selective channel activity. Furthermore, we show that activation of ZAR1 in the plant cell led to Glu11-dependent Ca2+ influx, perturbation of subcellular structures, production of reactive oxygen species, and cell death. The results thus support that the ZAR1 resistosome acts as a calcium-permeable cation channel to trigger immunity and cell death.


Subject(s)
Arabidopsis Proteins/metabolism , Arabidopsis/immunology , Arabidopsis/metabolism , Calcium/metabolism , Carrier Proteins/metabolism , Disease Resistance/immunology , Plant Immunity , Signal Transduction , Animals , Cell Death , Cell Membrane/metabolism , Cell Membrane Permeability , Glutamic Acid/metabolism , Lipid Bilayers/metabolism , Oocytes/metabolism , Plant Cells/metabolism , Protein Multimerization , Protoplasts/metabolism , Reactive Oxygen Species/metabolism , Single Molecule Imaging , Vacuoles/metabolism , Xenopus
6.
Micromachines (Basel) ; 12(4)2021 Apr 03.
Article in English | MEDLINE | ID: mdl-33916863

ABSTRACT

A chip-based electrochemical biosensor is developed herein for the detection of organophosphate (OP) in food materials. The principle of the sensing platform is based on the inhibition of dimethoate (DMT), a typical OP that specifically inhibits acetylcholinesterase (AChE) activity. Carbon nanotube-modified gold electrodes functionalized with polydiallyldimethylammonium chloride (PDDA) and oxidized nanocellulose (NC) were investigated for the sensing of OP, yielding high sensitivity. Compared with noncovalent adsorption and deposition in bovine serum albumin, bioconjugation with lysine side chain activation allowed the enzyme to be stable over three weeks at room temperature. The total amount of AChE was quantified, whose activity inhibition was highly linear with respect to DMT concentration. Increased incubation times and/or DMT concentration decreased current flow. The composite electrode showed a sensitivity 4.8-times higher than that of the bare gold electrode. The biosensor was challenged with organophosphate-spiked food samples and showed a limit of detection (LOD) of DMT at 4.1 nM, with a limit of quantification (LOQ) at 12.6 nM, in the linear range of 10 nM to 1000 nM. Such performance infers significant potential for the use of this system in the detection of organophosphates in real samples.

7.
Chin J Integr Med ; 27(1): 24-30, 2021 Jan.
Article in English | MEDLINE | ID: mdl-30656600

ABSTRACT

OBJECTIVE: To investigate the effect of Chinese compound Shensong Yangxin Capsule ( , SSYX) on myocardial microcirculation in myocardial-infarcted rabbits. METHODS: Myocardial infarction (MI) was established in rabbits by ligation of the left circumflex coronary. Thirty rabbits were randomly divided into the control group, the MI group (model), and the MI treated with SSYX group (MI+SSYX) by a random number table method. After 4 weeks of administration, low-energy real-time myocardial contrast echocardiography (RT-MCE) was conducted to assess the microcirculatory perfusion. Immunofluorescence double staining was used to detect the capillary density. The endothelial ultrastructure was observed with a transmission electron microscope. The mRNA expression levels of vascular endothelial growth factor (VEGF), endothelin 1 (ET-1), prostaglandin I2 (PGI2) and endothelial nitric oxide synthase (eNOS) were measured by real-time quantitative polymerase chain reaction (Real-time PCR). The plasmic levels of ET-1, thromboxane A2 (TXA2), nitric oxide (NO) and von willebrand factor (vWF) were examined with enzyme-linked immunosorbent assays (ELISA). RESULTS: SSYX significantly improved the myocardial blood volume, myocardial micro bubble velocity, and myocardial inflow according to the examination of RT-MCE, and it visibly ameliorated the capillary endothelial structure. Furthermore, compared with the MI group, the plasma levels of TXA2, ET-1 and vWF contents significantly decreased in the MI+SSYX group, and the ET-1 mRNA expression levels of myocardium in the border zone significantly decreased, and the VEGF, PGI2 and eNOS mRNA expression levels significantly increased (all P<0.05). CONCLUSIONS: SSYX has favorable advantages in ameliorating the impaired myocardial microcirculation following MI. The mechanisms of the effect are related to the ability of SSYX in balancing the endothelial-derived vasodilators and vasoconstrictors, and up-regulating the expression of VEGF and eNOS.


Subject(s)
Myocardial Infarction , Animals , Drugs, Chinese Herbal/pharmacology , Drugs, Chinese Herbal/therapeutic use , Medicine, Chinese Traditional , Microcirculation , Myocardial Infarction/drug therapy , Myocardium , Rabbits , Vascular Endothelial Growth Factor A
8.
J Cell Biol ; 219(3)2020 03 02.
Article in English | MEDLINE | ID: mdl-31962345

ABSTRACT

Clathrin-coated vesicles lose their clathrin lattice within seconds of pinching off, through the action of the Hsc70 "uncoating ATPase." The J- and PTEN-like domain-containing proteins, auxilin 1 (Aux1) and auxilin 2 (GAK), recruit Hsc70. The PTEN-like domain has no phosphatase activity, but it can recognize phosphatidylinositol phosphate head groups. Aux1 and GAK appear on coated vesicles in successive transient bursts, immediately after dynamin-mediated membrane scission has released the vesicle from the plasma membrane. These bursts contain a very small number of auxilins, and even four to six molecules are sufficient to mediate uncoating. In contrast, we could not detect auxilins in abortive pits or at any time during coated pit assembly. We previously showed that clathrin-coated vesicles have a dynamic phosphoinositide landscape, and we have proposed that lipid head group recognition might determine the timing of Aux1 and GAK appearance. The differential recruitment of Aux1 and GAK correlates with temporal variations in phosphoinositide composition, consistent with a lipid-switch timing mechanism.


Subject(s)
Auxilins/metabolism , Clathrin-Coated Vesicles/enzymology , Intracellular Signaling Peptides and Proteins/metabolism , Protein Serine-Threonine Kinases/metabolism , Animals , Auxilins/genetics , COS Cells , Chlorocebus aethiops , Clathrin-Coated Vesicles/genetics , HSC70 Heat-Shock Proteins/genetics , HSC70 Heat-Shock Proteins/metabolism , HeLa Cells , Humans , Intracellular Signaling Peptides and Proteins/genetics , Phosphatidylinositols/metabolism , Protein Serine-Threonine Kinases/genetics , Protein Transport , Signal Transduction , Time Factors
9.
Small ; 16(6): e1904462, 2020 02.
Article in English | MEDLINE | ID: mdl-31960583

ABSTRACT

Perovskite structured CsPbX3 (X = Cl, Br, or I) quantum dots (QDs) have attracted considerable interest in the past few years due to their excellent optoelectronic properties. Surface passivation is one of the main pathways to optimize the optoelectrical performance of perovskite QDs, in which the amino group plays an important role for the corresponding interaction between lead and halide. In this work, it is found that ammonia gas could dramatically increase photoluminescence of purified QDs and effectively passivate surface defects of perovskite QDs introduced during purification, which is a reversible process. This phenomenon makes perovskite QDs a kind of ideal candidate for detection of ammonia gas at room temperature. This QD film sensor displays specific recognition behavior toward ammonia gas due to its significant fluorescence enhancement, while depressed luminescence in case of other gases. The sensor, in turn-on mode, shows a wide detection range from 25 to 350 ppm with a limit of detection as low as 8.85 ppm. Meanwhile, a fast response time of ≈10 s is achieved, and the recovery time is ≈30 s. The fully reversible, high sensitivity and selectivity characteristics make CsPbBr3 QDs ideal active materials for room-temperature ammonia sensing.

10.
Int J Mol Med ; 44(4): 1255-1266, 2019 Oct.
Article in English | MEDLINE | ID: mdl-31432099

ABSTRACT

The primary mechanism underlying sepsis­induced cardiac dysfunction is loss of endothelial barrier function. Neuregulin­1 (NRG­1) exerts its functions on multiple targets. The present study aimed to identify the protective effects of NRG­1 in myocardial cells, including endothelial, anti­inflammatory and anti­apoptotic effects. Subsequent to lipopolysaccharide (LPS)­induced sepsis, rats were administered with either a vehicle or recombinant human NRG­1 (rhNRG­1; 10 µg/kg/day) for one or two days. H9c2 cardiomyoblasts were subjected to LPS (10 µg/ml) treatment for 12 and 24 h with or without rhNRG­1 (1 µg/ml). Survival rates were recorded at 48 h following sepsis induction. The hemodynamic method was performed to evaluate cardiac function, and myocardial morphology was observed. Von Willebrand Factor levels were detected using an immunofluorescence assay. Serum levels of tumor necrosis factor α, interleukin­6, intercellular cell adhesion molecule­1 and vascular endothelial growth factor were detected using an enzyme­linked immunosorbent assay; the reductase method was performed to detect serum nitric oxide levels. Apoptosis rates were determined using terminal deoxynucleotidyl transferase dUTP nick end labeling staining. Ras homolog family member A (RhoA) and Rho­associated protein kinase 1 (ROCK1) protein levels were assessed using western blotting. Transmission electron microscopy was used to observe endothelial cells and myocardial ultrastructure changes. Results revealed that NRG­1­treated rats displayed less myocardial damage compared with sham rats. NRG­1 administration strengthened the barrier function of the vasculature, reduced the secretion of endothelial­associated biomarkers and exerted anti­inflammatory and anti­apoptotic effects. In addition, NRG­1 inhibited RhoA and ROCK1 signaling. The results revealed that NRG­1 improves cardiac function, increases the survival rate of septic rats and exerts protective effects via multiple targets throughout the body. The present results contribute to the development of a novel approach to reverse damage to myocardial and endothelial cells during sepsis.


Subject(s)
Cardiotonic Agents/pharmacology , Endothelial Cells/drug effects , Endothelial Cells/metabolism , Heart Diseases/etiology , Heart Diseases/physiopathology , Neuregulin-1/pharmacology , Sepsis/complications , Animals , Apoptosis/drug effects , Biomarkers , Capillary Permeability/drug effects , Cytokines/metabolism , Heart Diseases/drug therapy , Heart Diseases/mortality , Heart Function Tests , Humans , Inflammation Mediators , Myocardium/metabolism , Myocardium/pathology , Myocardium/ultrastructure , Myocytes, Cardiac/drug effects , Myocytes, Cardiac/metabolism , Myocytes, Cardiac/ultrastructure , Oxidative Stress/drug effects , Protein Binding , Rats , Reactive Oxygen Species/metabolism , Recombinant Proteins/pharmacology
11.
Exp Ther Med ; 17(4): 3141-3149, 2019 Apr.
Article in English | MEDLINE | ID: mdl-30936986

ABSTRACT

Neuregulin-1 (NRG-1) is considered to be a potential therapeutic agent for cardiovascular diseases due to its diverse protective effects. The aim of the present study was to investigate the effect of NRG-1 on cardiac electrophysiology in rats with myocardial infarction (MI). The rats were randomly divided into three groups: The sham operation group (SO; n=8); MI group (n=8); and the MI with recombinant human NRG (rhNRG)-1 administration group (NRG-1 group; 10 µg/kg; n=8). A rat MI model was established via ligation of the left anterior descending coronary artery. The rats in the NRG-1 group received a 10 µg/kg rhNRG-1 injection through the tail vein 30 min prior to ligation. Following 24 h of intervention, the field potential (FP) parameters, including the interspike interval (ISI), field potential duration (FPD), FPrise, FPmin, FPmax and conduction velocity (CV), were measured using microelectrode array technology. Subsequently, burst pacing was performed to assess ventricular arrhythmia (VA) susceptibility in the left ventricle. FP parameters in the MI group were significantly different when compared with those observed in the SO group. ISI, FPD, FPrise and FPmax in the infarct, peri-infarct and normal zones, as well as the CV of the infarct and peri-infarct zones, were all significantly decreased, and FPmin in the normal zone was increased (P<0.05). However, when compared with the MI group, NRG-1 prolonged the ISI and FPD in the 3 zones, and increased FPrise in the infarct zone, FPmax in the normal zone and CV in the peri-infarct zone; it also decreased FPmin in the normal zone (P<0.05). Furthermore, the incidence of VA was significantly reduced in the NRG-1 group when compared with the MI group (P<0.05). In conclusion, NRG-1 improved cardiac electrophysiological properties and reduced VA susceptibility in acute MI.

12.
Chem Commun (Camb) ; 54(51): 7093-7094, 2018 06 21.
Article in English | MEDLINE | ID: mdl-29881839

ABSTRACT

Correction for 'A microporous Cu-MOF with optimized open metal sites and pore spaces for high gas storage and active chemical fixation of CO2' by Chao-Ying Gao et al., Chem. Commun., 2016, 52, 11147-11150.

13.
Zhonghua Wei Zhong Bing Ji Jiu Yi Xue ; 30(2): 140-144, 2018 Feb.
Article in Chinese | MEDLINE | ID: mdl-29402363

ABSTRACT

OBJECTIVE: To explore the protective effect of neuregulin-1 (NRG-1) on heart function and myocardium in rats with sepsis and its mechanism. METHODS: Healthy male Sprague-Dawly (SD) rats were divided into three groups according to random number table method, with 6 rats in each group. Sepsis model was established by cecal ligation and puncture (CLP group); rats in sham operation group (sham group) underwent the same procedure except ligation. Rats in NRG-1 pre-treatment group (NRG group) were intravenously injected with recombinant human NGR-1 (rhNRG-1) at the dose of 10 µg/kg through tail vein; rats in CLP group and sham group were treated with the same amount of saline. At 24 hours after CLP, hemodynamic method was used to evaluate the cardiac function, and myocardial morphology was observed with hematoxylin and eosin (HE) staining, enzyme linked immunosorbent assay (ELISA) was used to detect the levels of cardiac troponin T (cTnT), tumor necrosis factor-α (TNF-α), interleukin-1ß (IL-1ß) in serum and macrophage migration inhibitor factor (MIF) in myocardial tissue. RESULTS: (1) heart function: compared with the sham group, the mean arterial pressure (MAP), left ventricular systolic pressure (LVSP) and left ventricular pressure maximal rate of rise and fall (±dp/dt max) were significantly decreased in CLP group and NRG group, while the MAP, LVSP and ±dp/dt max in NRG group were significantly higher than those in CLP group [MAP (mmHg, 1 mmHg = 0.133 kPa): 125.78±8.15 vs. 113.05±5.85, LVSP (mmHg): 151.27±6.79 vs. 139.39±8.05, +dp/dt max (kPa/s): 4 389.59±332.38 vs. 3 706.85±451.31, -dp/dt max (kPa/s): 4 291.42±323.72 vs. 3 691.17±515.44, all P < 0.05]. (2) Myocardial injury: compared with the sham group, the levels of serum cTnT in CLP group and NRG group were significantly increased, while the levels of serum cTnT in NRG group were significantly lower than those in CLP group (ng/L: 206.37±67.28 vs. 344.13±80.95, P < 0.05), and the HE staining showed that myocardial pathological changes in NRG group were improved compared with the CLP group. (3) Inflammatory mediators level: compared with the sham group, the levels of serum TNF-α, IL-1ß and myocardial MIF were significantly increased in CLP group and NRG group, while the indicators in NRG group were lower than those in CLP group [TNF-α (ng/L): 52.77±3.43 vs. 97.19±13.98, IL-1ß (ng/L): 40.25±5.48 vs. 56.05±6.88, MIF (µg/L): 1.92±0.16 vs. 2.87±0.10, all P < 0.05]. CONCLUSIONS: NRG-1 can reduce circulating levels of inflammatory factors in rats with sepsis, adjust myocardial MIF level, and alleviate myocardial cell injury, thereby improving cardiac function, and play a role in myocardial protection.


Subject(s)
Sepsis , Animals , Disease Models, Animal , Inflammation Mediators , Interleukin-1beta , Male , Neuregulin-1 , Rats , Rats, Sprague-Dawley , Tumor Necrosis Factor-alpha
14.
Neural Regen Res ; 12(11): 1905-1910, 2017 Nov.
Article in English | MEDLINE | ID: mdl-29239338

ABSTRACT

Sympathetic nerve and vagus nerve remodeling play an important part in cardiac function post-myocardial infarction (MI). Increasing evidence indicates that neuregulin-1 (NRG-1) improves cardiac function following heart failure. Since its impact on cardiac function and neural remodeling post-MI is poorly understood, we aimed to investigate the role of NRG-1 in autonomic nervous system remodeling post-MI. Forty-five Sprague-Dawley rats were equally randomized into three groups: sham (with the left anterior descending coronary artery exposed but without ligation), MI (left anterior descending coronary artery ligation), and MI plus NRG-1 (left anterior descending coronary artery ligation followed by intraperitoneal injection of NRG-1 (10 µg/kg, once daily for 7 days)). At 4 weeks after MI, echocardiography was used to detect the rat cardiac function by measuring the left ventricular end-systolic inner diameter, left ventricular diastolic diameter, left ventricular end-systolic volume, left ventricular end-diastolic volume, left ventricular ejection fraction, and left ventricular fractional shortening. mRNA and protein expression levels of tyrosine hydroxylase, growth associated protein-43 (neuronal specific protein), nerve growth factor, choline acetyltransferase (vagus nerve marker), and vesicular acetylcholine transporter (cardiac vagal nerve fiber marker) in ischemic myocardia were detected by real-time PCR and western blot assay to assess autonomous nervous remodeling. After MI, the rat cardiac function deteriorated significantly, and it was significantly improved after NRG-1 injection. Compared with the MI group, mRNA and protein levels of tyrosine hydroxylase and growth associated protein-43, as well as choline acetyltransferase mRNA level significantly decreased in the MI plus NRG-1 group, while mRNA and protein levels of nerve growth factor and vesicular acetylcholine transporters, as well as choline acetyltransferase protein level slightly decreased. Our results indicate that NRG-1 can improve cardiac function and regulate sympathetic and vagus nerve remodeling post-MI, thus reaching a new balance of the autonomic nervous system to protect the heart from injury.

15.
Nature ; 552(7685): 410-414, 2017 12 21.
Article in English | MEDLINE | ID: mdl-29236694

ABSTRACT

Vesicular carriers transport proteins and lipids from one organelle to another, recognizing specific identifiers for the donor and acceptor membranes. Two important identifiers are phosphoinositides and GTP-bound GTPases, which provide well-defined but mutable labels. Phosphatidylinositol and its phosphorylated derivatives are present on the cytosolic faces of most cellular membranes. Reversible phosphorylation of its headgroup produces seven distinct phosphoinositides. In endocytic traffic, phosphatidylinositol-4,5-biphosphate marks the plasma membrane, and phosphatidylinositol-3-phosphate and phosphatidylinositol-4-phosphate mark distinct endosomal compartments. It is unknown what sequence of changes in lipid content confers on the vesicles their distinct identity at each intermediate step. Here we describe 'coincidence-detecting' sensors that selectively report the phosphoinositide composition of clathrin-associated structures, and the use of these sensors to follow the dynamics of phosphoinositide conversion during endocytosis. The membrane of an assembling coated pit, in equilibrium with the surrounding plasma membrane, contains phosphatidylinositol-4,5-biphosphate and a smaller amount of phosphatidylinositol-4-phosphate. Closure of the vesicle interrupts free exchange with the plasma membrane. A substantial burst of phosphatidylinositol-4-phosphate immediately after budding coincides with a burst of phosphatidylinositol-3-phosphate, distinct from any later encounter with the phosphatidylinositol-3-phosphate pool in early endosomes; phosphatidylinositol-3,4-biphosphate and the GTPase Rab5 then appear and remain as the uncoating vesicles mature into Rab5-positive endocytic intermediates. Our observations show that a cascade of molecular conversions, made possible by the separation of a vesicle from its parent membrane, can label membrane-traffic intermediates and determine their destinations.


Subject(s)
Clathrin-Coated Vesicles/chemistry , Clathrin-Coated Vesicles/metabolism , Clathrin/metabolism , Coated Pits, Cell-Membrane/metabolism , Endocytosis , Endosomes/metabolism , Phosphatidylinositols/metabolism , Animals , Auxilins/metabolism , COS Cells , Cell Line , Cell Membrane/chemistry , Cell Membrane/metabolism , Chlorocebus aethiops , Coated Pits, Cell-Membrane/chemistry , Endosomes/chemistry , Humans , Phosphatidylinositol 4,5-Diphosphate/metabolism , Phosphatidylinositol Phosphates/metabolism , Phosphatidylinositols/analysis , Phosphatidylinositols/chemistry , Phosphoric Monoester Hydrolases/metabolism , Phosphorylation , Phosphotransferases/metabolism , rab5 GTP-Binding Proteins/metabolism
16.
Chin Med J (Engl) ; 130(14): 1639-1647, 2017 Jul 20.
Article in English | MEDLINE | ID: mdl-28685712

ABSTRACT

BACKGROUND: Pharmacological therapy for congestive heart failure (CHF) with ventricular arrhythmia is limited. In the study, our aim was to evaluate the effects of Chinese traditional medicine Shensong Yangxin capsules (SSYX) on heart rhythm and function in CHF patients with frequent ventricular premature complexes (VPCs). METHODS: This double-blind, placebo-controlled, multicenter study randomized 465 CHF patients with frequent VPCs to the SSYX (n = 232) and placebo groups (n = 233) for 12 weeks of treatment. The primary endpoint was the VPCs monitored by a 24-h ambulatory electrocardiogram. The secondary endpoints included the left ventricular ejection fraction (LVEF), left ventricular end-diastolic diameter, N-terminal pro-brain natriuretic peptide (NT-proBNP), New York Heart Association (NYHA) classification, 6-min walking distance (6MWD), Minnesota Living with Heart Failure Questionnaire (MLHFQ) scores, and composite cardiac events (CCEs). RESULTS: The clinical characteristics were similar at baseline. SSYX caused a significantly greater decline in the total number of VPCs than the placebo did (-2145 ± 2848 vs. -841 ± 3411, P < 0.05). The secondary endpoints of the LVEF, NYHA classification, NT-proBNP, 6MWD, and MLHFQ scores showed a greater improvements in the SSYX group than in the placebo group (ΔLVEF at 12th week: 4.75 ± 7.13 vs. 3.30 ± 6.53; NYHA improvement rate at the 8th and 12th week: 32.6% vs. 21.8%, 40.5% vs. 25.7%; mean level of NT-proBNP in patients with NT-proBNP ≥125 pg/ml at 12th week: -122 [Q1, Q3: -524, 0] vs. -75 [Q1, Q3: -245, 0]; Δ6MWD at 12th week: 35.1 ± 38.6 vs. 17.2 ± 45.6; ΔMLHFQ at the 4th, 8th, and 12th week: -4.24 ± 6.15 vs. -2.31 ± 6.96, -8.19 ± 8.41 vs. -3.25 ± 9.40, -10.60 ± 9.41 vs. -4.83 ± 11.23, all P < 0.05). CCEs were not different between the groups during the study period. CONCLUSIONS: In this 12-week pilot study, SSYX was demonstrated to have the benefits of VPCs suppression and cardiac function improvement with good compliance on a background of standard treatment for CHF. TRIAL REGISTRATION: www.chictr.org.cn, ChiCTR-TRC-12002061 (http://www.chictr.org.cn/showproj.aspx?proj=7487) and Clinicaltrials.gov, NCT01612260 (https://clinicaltrials.gov/ct2/show/NCT01612260).


Subject(s)
Heart Failure/drug therapy , Medicine, Chinese Traditional/methods , Ventricular Premature Complexes/drug therapy , Adolescent , Adult , Aged , Double-Blind Method , Drugs, Chinese Herbal/therapeutic use , Female , Heart Failure/metabolism , Heart Rate/drug effects , Humans , Male , Middle Aged , Ventricular Function, Left/drug effects , Ventricular Premature Complexes/metabolism , Young Adult
17.
Dalton Trans ; 46(20): 6756-6761, 2017 May 23.
Article in English | MEDLINE | ID: mdl-28489100

ABSTRACT

A novel 3D copper-phosphonate network, with the general formula Cu7(H1L)2(TPT)3(H2O)6, namely compound 1, has been synthesized using a rigid tetrahedral linker tetraphenylsilane tetrakis-4-phosphonic acid (H8L) and a nitrogen-containing ancillary ligand (TPT: [5-(4-(1H-1,2,4-triazol-1-yl)phenyl)-1H-tetrazole]) under hydrothermal conditions. The compound was fully characterized using PXRD, ICP, IR, TGA and elemental analysis. Compound 1 can be used as an efficient catalyst for the CO2 coupling reaction that is greatly superior to many conventional MOF-based catalysts, where porosity is always mentioned and used. In addition, it shows excellent catalytic performance for ring-opening reactions with epoxides under ambient conditions. Additionally, compound 1 can be recycled at least three times without a significant compromise in the activity in the two catalytic reactions.

18.
Chem Commun (Camb) ; 53(30): 4199-4202, 2017 Apr 11.
Article in English | MEDLINE | ID: mdl-28256652

ABSTRACT

The magnetic nanocomposite Fe3O4@ZIF-8 was for the first time used as an excellent adsorbent for the fast adsorption and separation of UO22+ ions from aqueous solutions. This material exhibited an unprecedented adsorption capacity of 523.5 mg U per g and a remarkable selectivity towards UO22+/Ln3+ at pH = 3.

19.
Small ; 13(16)2017 04.
Article in English | MEDLINE | ID: mdl-28151583

ABSTRACT

Sub-nanometer Pt@Rh nanoparticles highly dispersed on MIL-125-derived porous TiO2 nanoplates are successfully prepared for the first time by a photochemical route, where the porous TiO2 nanoplates with a relatively high specific surface area play a dual role as both effective photoreductant and catalyst support. The resulting Pt@Rh/p-TiO2 can be utilized as a highly active catalyst.

20.
Chemistry ; 23(12): 2852-2857, 2017 Feb 24.
Article in English | MEDLINE | ID: mdl-28066946

ABSTRACT

A series of heterometallic lanthanide (Ln)-Ru coordination polymers, denoted Gd-1, Yb-2, and Nd-3, were prepared by solvothermal reaction of a carboxylate derivative of [Ru(bpy)3 ]2+ (Rubpy, bpy=2,2'-bipyridine), oxalic acid, and Ln(OAc)3 by using the metalloligand strategy. Single-crystal X-ray diffraction indicated that the resulting isostructural heterometallic complexes have 1D butterfly-shaped Ln-Ru-based coordination chains but show slight differences in the coordination environments of the Ln centers. The introduced Ru(bpy) metalloligands could act as good light-harvesting antennas to effectively sensitize near-infrared (NIR) luminescence by energy transfer from the triplet metal-to ligand charge transfer state of Rubpy units to Ln (Yb or Nd) under the excitation in the visible-light region. Additionally, dopant-concentration-dependent behavior of the Ru-based emission and sensitized NIR emission was demonstrated in Gd-1. Finally, the magnetocaloric effect of Gd-1 was studied. The preparation of such heterometallic coordination polymers offers a versatile platform to investigate dimensionally controlled properties.

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