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1.
J Org Chem ; 84(11): 6765-6779, 2019 06 07.
Artículo en Inglés | MEDLINE | ID: mdl-31070032

RESUMEN

The structural revision of cyclotetrapeptide asperterrestide A has been achieved based on total synthesis and molecular modeling. For these studies, (2 R,3 S)-MePhe(3-OH) and (2 S,3 S)-MePhe(3-OH) suitably protected for peptide synthesis were prepared via a stereoselective reduction of a ketone precursor derived from L- or d-serine, using L-selectride or DIBAL-H. The synthesis of the proposed structure of asperterrestide A (1a) was accomplished by solution-phase synthesis of a linear precursor followed by macrolactamization. The NMR spectra of our synthetic 1a were not identical to those reported for the natural compound. Molecular modeling studies suggested that the correct structure 1b was the one in which the stereochemistry at the α-positions of the Ala and MePhe(3-OH) residues is the opposite to that of the proposed structure. This was confirmed by the total synthesis of 1b and its subsequent structural characterization.

2.
ACS Appl Mater Interfaces ; 16(6): 7904-7916, 2024 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-38302102

RESUMEN

Noncontact triboelectric sensors (TESs) have the potential to enhance self-powered sensing performance by eliminating the need for physical contact. This study demonstrates a strategy to construct noncontact TES that enables self-powered sensing and vibration signal acquisition with high sensitivity and wide bandwidth. The incorporation of carbon nanotubes into nitrocellulose (CNTs/NC) endows the tribopositive layer with larger inner micro/nanocapacitances, consequently augmenting the charge storage capacity. As a result, the contactless sensing performance of CNTs/NC-based TES (CNTs/NC-TES) was enhanced by 146%. Correspondingly, the related theory and working mechanism of noncontact sensing were demonstrated. Furthermore, the CNTs/NC-TES exhibits optimal distance response sensitivity of 57.10 V mm-1, a wide-bandwidth response from 0.1 to 4000 Hz, and relative humidity (RH) stability. This contactless CNTs/NC-TES has the potential for high sensitivity and wide frequency vibration monitoring in a high-RH environment.

3.
Heliyon ; 10(13): e33418, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-39040343

RESUMEN

Wang's metabolic formula (WMF) is a traditional Chinese medicine formula developed under the guidance of Professor Kungen Wang. WMF has been clinically utilized for several years. However, the therapeutic mechanism of WMF in treating metabolic-associated fatty liver disease (MAFLD) remains unclear. In this study, we performed phytochemical analysis on WMF using LC-MS. To study the role of WMF in MAFLD, we orally administered WMF (20.6 g/kg) to male MAFLD mice induced by a high-cholesterol high-fat diet (HCHFD). Then pathological, biochemical, and metabolomic analyses were performed. The main components of WMF are chlorogenic acid, geniposide, albiflorin, paeoniflorin, and calycosin-7-O-glucoside. MAFLD mice treated with WMF exhibited significant improvements in obesity, abnormal lipid metabolism, inflammation, and liver pathology. WMF decreased aspartate aminotransferase (AST), alanine aminotransferase (ALT), and triglyceride (TG) levels in the serum of MAFLD mice while increasing high-density lipoprotein cholesterol (HDL-c) levels. WMF lowered liver TG levels and inflammatory factors (IL-1ß, IL-6, TNF-α, and NF-κB). Metabolomic analysis of the liver annotated 78 differentially regulated metabolites enriched in four pathways: glycerophospholipid metabolism, retinol metabolism, PPAR signaling pathway, and choline metabolism. Western blot experiments showed that WMF increased the expression of PPAR-α, PPAR-ß, and RXR in the liver while decreasing the expression of RAR. The study demonstrates that WMF has a solid preventive and therapeutic effect on MAFLD. The anti-inflammatory and regulation of abnormal liver metabolism activities of WMF involve retinol metabolism and the PPAR signaling pathway.

4.
J Colloid Interface Sci ; 629(Pt B): 492-500, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36174292

RESUMEN

The low ionic conductivity at room temperature and poor dimensional stability at high temperature of polyethylene oxide (PEO)-based solid electrolytes greatly limit the development and utilization of solid polymer electrolytes (SPEs). To reconcile the contradiction between electrochemical performance and mechanical strength of PEO-based SPEs, a cross-linking structure with active -CH2CH2O- soft chains that doped with rigid segments is designed and prepared through a method of green ultraviolet irradiation without solvent. The obtained solid film shows a high ionic conductivity of 0.2 mS·cm-1 and an ionic transference number of 0.51 at room temperature. The activation energy value of 1.92 kJ·mol-1 gives evidence for a favorable migration mechanism of PTP-SPE. A combination of flexibility and strength can be realized by molecular structure design with a tensile elongation of 40%. The reversible overpotential in galvanostatic cycling over 500 h of a Li||Li symmetrical cell indicates that the compact PTP-SPE can inhibit the formation of lithium dendrites. This work provides a new strategy for designing high-performance composite solid electrolytes at room temperature.

5.
ACS Appl Mater Interfaces ; 15(46): 54166-54175, 2023 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-37943181

RESUMEN

Oil spills are one of the most dangerous sources that cause serious environmental pollution and fire and explosion. In this work, multifunctional separator silica@polydivinylbenzene/poly 2,6-dimethyl-1, 4-phenyl ether (silica@PDVB/PPE) Janus particles were fabricated via seed emulsion polymerization, causing phase segregation as well as selective modification. The epoxy modified silica is partially covalently bonded to the fabric substrate surface by simple spraying to achieve a strong composite coating. The low surface energy PDVB/PPE forms a micronano rough layered surface, which can achieve a super hydrophobic and lipophile surface (WCA = 155°) and obtain a high flux separation of water and oil at 32,700 L·m-2·h-1. At the same time, the Janus composite fabric coating has the advantages of high heat resistance and flame retardant, which is realized by halogen-free flame-retardant unsaturated polyphosphate (PPE), making Janus fabric have potential value in separating oil-water mixtures and fire protection applications. In addition, the coating shows excellent chemical durability. After soaking in various aqueous solvents and organic solvents for 30 h, it can still maintain superhydrophobicity and flame retardant. The coating still has water repellency and flame retardant after 50 washings and mechanical wear and has good mechanical durability.

6.
J Colloid Interface Sci ; 617: 73-83, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35259513

RESUMEN

Because of different atomic arrangements and/or different exposed atoms on different surfaces of crystalline particles, different physical and chemical properties can be resulted and exhibited. In this work, we prepared BiOCl with {110} crystal facet by introducing urea as the structure-directing agent, and constructed oxygen vacancies (OVs) in BiOCl (110) to form BiOCl (110)-OV. Control of exposure surface can improve photocatalyst activity and the defect level caused by OVs can improve charge separation and light absorption, thereby further enhancing the production of free radicals and the activation of pollutants. Due to the synergistic effect of the hierarchical microsphere structure of BiOCl and OVs, the degradation rate of tetracycline hydrochloride (20 mg/L) in the presence of BiOCl (110)-OV can reach 95.1% after 15 min of the simulated sunlight illumination. This research provides novel ideas for the design and development of photocatalyst with hierarchical structure and oxygen vacancy defects.


Asunto(s)
Bismuto , Oxígeno , Bismuto/química , Catálisis , Microesferas , Fotólisis
7.
Chemosphere ; 289: 133262, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34906528

RESUMEN

High electron transfer rates and a higher number of electron transfer active sites play important roles in inhibiting the recombination of photogenerated electron-hole pairs. In the experiments described in this article, the g-C3N4/BC/Bi25FeO40 composite material was prepared to use biochar (BC) as the conductive channel. The presence of BC significantly increases the electron transfer rate due to its excellent electrical conductivity and can provide more electron transfer active sites. At the same time, BC provides a larger surface area and has a loose porous structure, which lead to excellent adsorption performance. Based on various characterization results, it was confirmed that the Z-scheme heterojunction was successfully constructed between g-C3N4 and Bi25FeO40. The photocatalytic experiment results showed that the degradation efficiency of g-C3N4/BC/Bi25FeO40 on the tetracycline hydrochloride (TCH) could reach 92.2% within 60 min. Parameters such as circulation stability, pH value of the solution and the amount of composite materials were studied. The synthesized composite material has good reusability and high efficiency in a wide pH range of 3-11. Its excellent photocatalytic activity is attributed to the formation of an effective Z-scheme heterostructure, as well as the rapid photoelectron transfer and excellent adsorption capacity of BC. This work provides a way to design new photocatalysts using semiconductor composite materials and BC materials.


Asunto(s)
Electrones , Tetraciclina , Catálisis , Carbón Orgánico , Luz
8.
J Interferon Cytokine Res ; 42(11): 580-589, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36346319

RESUMEN

Type I interferons (IFN-Is) play central roles in regulating immune responses. The role of IFNAR2 in IFN-I signaling is an open question since a previous report showed that IFNß was still functional in the absence of IFNAR2 in mice. In this study, we report that IFN-I signaling in human monocyte-derived THP1 cells absolutely depends on IFNAR2, as determined by using a knockout mutant made by CRISPR/Cas9. Additionally, we demonstrated that a 7-bp deletion mutant (Δ7) of IFNAR2 remains responsive to IFNß stimulation and upregulates a subset of interferon-stimulated genes (s-ISGs). The s-ISGs largely overlap with tonic ISGs, which depend on the basal expression level of IFN-I. We also showed that IFN signaling in Δ7 still depends on IFNAR2. Then, we found that the 7-bp deletion in the genome results in the loss of the entire third exon (42 bp) from the mRNA and in the expression of a functionally impaired IFNAR2. These findings clarified the requirement of IFNAR2 for human IFN-I signaling and highlighted that caution should be used with CRISPR/Cas9 technology to prevent misleading interpretations caused by residual protein expression due to exon skipping or other mechanisms.


Asunto(s)
Interferón Tipo I , Receptor de Interferón alfa y beta , Humanos , Antivirales/farmacología , Sistemas CRISPR-Cas , Exones/genética , Interferón Tipo I/metabolismo , Interferón beta/genética , Interferón beta/metabolismo , Receptor de Interferón alfa y beta/genética , Receptor de Interferón alfa y beta/metabolismo
9.
Molecules ; 15(7): 4589-98, 2010 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-20657379

RESUMEN

Three new compounds were isolated from the dried bulbs of Allium macrostemon Bunge. Their structures were elucidated from their spectral data as (25R)-26-O-beta-D-glucopyranosyl-5alpha-furostane-3beta,12beta,22,26-tetraol-3-O-beta-D-glucopyranos-yl (1-->2) [beta-D-glucopyranosyl (1-->3)]-beta-D-glucopyranosyl (1-->4)-beta-D-galactopyranoside (1), (25R)-26-O-beta-D-glucopyranosyl-5alpha-furostane-3beta,12alpha,22,26-tetraol-3-O-beta-D-glucopyranosyl (1-->2) [beta-D-glucopyranosyl (1-->3)]-beta-D-glucopyranosyl (1-->4)-beta-D-galacto- pyranoside (2) and (25R)-26-O-beta-D-glucopyranosyl-5beta-furostane-3beta,12alpha,22,26-tetraol-3-O-beta-D-glucopyranosyl (1-->2)-beta-D-galactopyranoside (3), respectively. The inhibition effect of all compounds on CD40 ligand (CD40L) expression on the membrane of activated platelets stimulated by ADP was tested. Compounds 1 and 2 exhibited significant inhibitory activities in a dose dependent manner (P < 0.05), suggesting their potential application as CD40L inhibitors.


Asunto(s)
Allium/química , Ligando de CD40/antagonistas & inhibidores , Glicósidos/análisis , Activación Plaquetaria/efectos de los fármacos , Adenosina Difosfato/farmacología , Plaquetas/efectos de los fármacos , Conformación de Carbohidratos , Relación Dosis-Respuesta a Droga , Glicósidos/aislamiento & purificación , Glicósidos/farmacología , Estructura Molecular , Análisis Espectral , Esteroides
10.
J Environ Sci (China) ; 21(6): 764-9, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19803080

RESUMEN

Mechanism of treatment and remediation of synthetic Cu2+ polluted water body by membrane and electro-winning combination process was investigated. The influences of electrolysis voltage, pH, and electrolysis time on the metal recovery efficiencies were studied. Relationship between trans-membrane pressure drop (DeltaP), additions ratio, initial Cu2+ concentration on operating efficiency, stability of membrane and the possibility of water reuse were also investigated. The morphology of membrane and electrodes were observed using scanning electron microscopy (SEM), the composition of surface deposits was ascertained using combined energy dispersive X-ray spectroscopy (EDX) and atomic absorption spectrophotometer. The results showed that using low pressure reverse osmosis (LPRO), Cu2+ concentration could increase from 20 to 100 mg/L or even higher in concentrated solutions and permeate water conductivity could be less than 20 microS/cm. The addition of sodium dodecy/sulfate sodium dodecyl sulfate improved Cu2+ removal efficiency, while EDTA had little side influence. In electro-reduction process, using plante electrode cell, Cu2+ concentration could be further reduced to 5 mg/L, and the average current efficiency ranged from 9% to 40%. Using 3D electrolysis treatment, Cu2+ concentration could be reduced to 0.5 mg/L with a current efficiency range 60%-70%.


Asunto(s)
Cobre/química , Técnicas Electroquímicas , Contaminantes Químicos del Agua/química , Purificación del Agua , Abastecimiento de Agua/análisis , Quelantes/química , Ácido Edético/química , Humanos , Residuos Industriales , Dodecil Sulfato de Sodio/química , Tensoactivos/química , Contaminación del Agua , Purificación del Agua/instrumentación , Purificación del Agua/métodos
11.
Sci Rep ; 7: 45395, 2017 03 28.
Artículo en Inglés | MEDLINE | ID: mdl-28350008

RESUMEN

Tumour-induced dendritic cell (DC) dysfunction plays an important role in cancer immune escape. However, the underlying mechanisms are not yet fully understood, reflecting the lack of appropriate experimental models both in vivo and in vitro. In the present study, an in vitro study model for tumour-induced DC dysfunction was established by culturing DCs with pooled sera from multiple non-small cell lung cancer (NSCLC) patients. The results demonstrated that tumour-induced human monocyte-derived DCs exhibited systematic functional deficiencies. Transcriptomics analysis revealed that the expression of major functional cluster genes, including the MHC class II family, cytokines, chemokines, and co-stimulatory molecules, was significantly altered in tumour-induced DCs compared to that in control cells. Further examination confirmed that both NF-κB and STAT3 signalling pathways were simultaneously repressed by cancer sera, suggesting that the attenuated NF-κB and STAT3 signalling could be the leading cause of DC dysfunction in cancer. Furthermore, reversing the deactivated NF-κB and STAT3 signalling could be a strategy for cancer immunotherapy.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/inmunología , Células Dendríticas/inmunología , Neoplasias Pulmonares/inmunología , FN-kappa B/antagonistas & inhibidores , Factor de Transcripción STAT3/antagonistas & inhibidores , Escape del Tumor/inmunología , Adulto , Anciano , Presentación de Antígeno/inmunología , Antígenos de Neoplasias/inmunología , Carcinoma de Pulmón de Células no Pequeñas/patología , Femenino , Perfilación de la Expresión Génica , Antígenos de Histocompatibilidad Clase II/inmunología , Humanos , Neoplasias Pulmonares/patología , Masculino , Persona de Mediana Edad , Transducción de Señal/inmunología
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