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1.
Int J Biol Macromol ; 278(Pt 2): 134886, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39168195

RESUMEN

The development of multifunctional coatings is a trend. Here, a conductive and superhydrophobic coating with nest-like structure was prepared on the wood or polyurethane (PU) sponge by spraying or soaking methods. The coating contains lignin and carboxylated multi-wall carbon nanotubes (MWCNT) as the main materials, both methyl trimethoxysilane (MTMS) and polydimethylsiloxane (PDMS) as the modifiers. And benefiting from the protective effect of the nest-like structure, the coating exhibits excellent abrasion resistance (withstanding 43 abrasion cycles), stability, and UV resistance (little change in water contact angle after 240 h of ultraviolet (UV) irradiation) by optimizing the proportions. Additionally, the coating provides eminent deicing (complete removal after 142.7 s) and self-cleaning on the wood, as well as the superior sensing performance and oil absorption (15.0-49.6 g/g for various oils) on the PU sponge. When assembled into compressible piezoresistive sensor, it could clearly sense the signals of rapid, short, circulation, different speed and deformation, possessing a prosperous wearable device prospect. It is envisaged that the coating supplies a new platform for superhydrophobicity, wearable electronics and oil absorption.


Asunto(s)
Interacciones Hidrofóbicas e Hidrofílicas , Lignina , Nanotubos de Carbono , Dispositivos Electrónicos Vestibles , Nanotubos de Carbono/química , Lignina/química , Aceites/química , Conductividad Eléctrica , Poliuretanos/química , Silanos/química , Dimetilpolisiloxanos/química
2.
J Environ Manage ; 358: 120909, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38642487

RESUMEN

Achieving an equilibrium between exceptional oil absorption and remarkable elasticity has emerged as a formidable challenge for magnetic porous materials designed for oil absorption. Here, we propose an original, magnetic and superhydrophobic cellulose nanofibril (CNF) based aerogel system with a rope-ladder like skeleton by to greatly improve the issue. Within this system, CNF as the skeleton was combined with multiwalled carbon nanotubes (MWCNT)@Fe3O4 as the magnetic and enhanced component, both methyltrimethoxysilane (MTMS) and acetonitrile-extracted lignin (AEL) as the soft-hard associating constituents. The resultant CNF based aerogel shows a rope-ladder like pore structure to contribute to high elasticity and excellent oil absorption (28.34-61.09 g/g for various oils and organic solvents) under the synergistic effect of Fe3O4@MWCNT, AEL and MTMS, as well as good specific surface area (27.97 m2/g), low density (26.4 mg/cm3). Notably, despite the introduced considerable proportion (0.5 times of mass-CNF) of Fe3O4@MWCNT, the aerogel retained an impressive compression-decompression rate (88%) and the oil absorption efficiency of above 87% for various oils due to the soft-hard associating structure supported by both MTMS and AEL. This study provides a prospective strategy to balance between high elasticity and excellent oil absorption of CNF based aerogel doping inorganic particles.


Asunto(s)
Celulosa , Interacciones Hidrofóbicas e Hidrofílicas , Nanofibras , Celulosa/química , Nanofibras/química , Aceites/química , Geles/química , Nanotubos de Carbono/química , Elasticidad , Porosidad
3.
Int J Biol Macromol ; 265(Pt 1): 130807, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38484808

RESUMEN

Magnetic superhydrophobic materials have broad application prospect in oil-water separation. In this study, a magnetic and superhydrophobic aerogel with lamellar structure was successfully prepared using cellulose nanofibrils (CNF) as the skeleton, Fe3O4 as the magnetic ion, 1H, 1H, 2H, 2H trialkylfluorooctane triethoxysilane (FS) and 3-(2-aminoethyl amino)-propyl trimethoxysilane (AS) as the combined modifier. The prepared aerogel shows lower density (38.63 mg/cm3), excellent magnetic (15.13 emu/g), high elasticity and good oil sorption properties (21 g/g). In addition, FS/AS also exhibits excellent mechanical properties and superhydrophobic ability (water contact angle (WCA) of 151.9 ± 1.4°), as it provides sufficient toughness and low surface energy for the layer-branch structure. It should be noted that the entire preparation process is carried out in the aqueous phase, without the use of any organic solvents, providing a green oil-water separation strategy.


Asunto(s)
Celulosa , Agua , Elasticidad , Radiofármacos , Interacciones Hidrofóbicas e Hidrofílicas
4.
Immun Inflamm Dis ; 12(2): e1132, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38415922

RESUMEN

BACKGROUND: Neuropathic pain (NP) is a chronic pathological pain that affects the quality of life and is a huge medical burden for affected patients. In this study, we aimed to explore the effects of secreted phosphoprotein 1 (SPP1) on NP. METHODS: We established a chronic constriction injury (CCI) rat model, knocked down SPP1 via an intrathecal injection, and/or activated the extracellular signal-regulated kinase (ERK) pathway with insulin-like growth factor 1 (IGF-1) treatment. Pain behaviors, including paw withdrawal threshold (PWT), paw withdrawal latency (PWL), lifting number, and frequency, were assessed. After sacrificing rats, the L4-L5 dorsal root ganglion was collected. Then, SPP1 levels were determined using quantitative polymerase chain reaction (qPCR) and western blot analysis. The levels of interleukin (IL)-1ß, tumor necrosis factor (TNF)-α, IL-6, IL-10, epidermal growth factor (EGF), vascular endothelial growth factor (VEGF), and transforming growth factor (TGF)-ß were determined using qPCR and enzyme-linked immunosorbent assay. The levels of ERK pathway factors were determined via western blot analysis. RESULTS: We found that CCI decreased PWT and PWL, increased the lifting number and frequency, and upregulated SPP1 levels. The loss of SPP1 reversed these CCI-induced effects. Additionally, CCI upregulated IL-1ß, TNF-α, IL-6, EGF, and VEGF levels, downregulated TGF-ß levels, and activated the ERK pathway, while silencing of SPP1 abrogated these CCI-induced effects. Moreover, IGF-1 treatment reversed the effects of SPP1 loss. CONCLUSIONS: The data indicate that silencing SPP1 attenuates NP via inactivation of the ERK pathway, suggesting that SPP1 may be a promising target for NP treatment.


Asunto(s)
Quinasas MAP Reguladas por Señal Extracelular , Neuralgia , Humanos , Animales , Ratas , Factor A de Crecimiento Endotelial Vascular , Factor I del Crecimiento Similar a la Insulina/genética , Factor de Crecimiento Epidérmico , Osteopontina , Interleucina-6 , Calidad de Vida , Neuralgia/etiología , Interleucina-1beta , Transducción de Señal , Nervio Ciático
5.
Org Lett ; 26(6): 1249-1254, 2024 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-38305700

RESUMEN

An efficient copper catalytic system has been established for the synthesis of highly functional indolizines through oxidative [3 + 2] cycloaddition of enamines and pyridotriazoles. This modular platform is compatible with a broad range of functional groups, including natural and complex skeletons, allowing for late-stage modifications. It features a step-economical, highly regioselective, and easy-handling procedure and has been applied in constructing small molecules of potent activity toward inhibiting the VEGF-NRP1 interaction through a one-pot reaction of pyridotriazoles, amines, and aldehydes.

6.
Int J Biol Macromol ; 258(Pt 2): 128918, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38134986

RESUMEN

Applications for polylactic acid (PLA) are significantly impacted by its poor mechanical properties and lack of thermal stability. The goal of this work is to bridge the gap of poor compatibility among the components and enhance their interface interlocking capability to improve the toughness and thermal stability. Ultrafine bamboo charcoal (UFBC) was treated through deep eutectic solvent (DES) method to deposit sodium lignosulfonate (LS) on its surface. LS was used with PLA as a bio-coupling agent to create an eco-friendly PLA composite film with a wide range of characteristics. Benefiting from the penetration of PLA to the internal pores in UFBC, the resultant L-UFBC/PLA film has a good mechanical interlocking structure. Ls can increase the compatibility and strengthen the interface interlocking capability through DES method, which greatly improves the mechanical properties of the system. In comparison to pure PLA one, the elongation at break was 136.24 % greater, and the crystallinity (Xc) increased from 1.09 % to 3.33 %. Furthermore, the thermal stability of the system was also improved, and the residual at 600 °C rose by 4.83 %. These characteristics offer the prepared L-UFBC/PLA film a wide range of potential applications in the packaging, medical, agricultural, and other sectors.


Asunto(s)
Agricultura , Carbón Orgánico , Análisis por Conglomerados , Poliésteres
7.
Polymers (Basel) ; 15(2)2023 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-36679241

RESUMEN

It is of great significance to develop green, sustainable additives to improve the thermal stability and flame retardancy of biopolymers. In this work, a synergistic modification of P/N elements to bamboo biochar (mBC) was successfully achieved by grafting a reaction of phytic acid and urea with preoxidized bamboo biochar. Fourier transform infrared spectroscopy, X-ray diffraction, nuclear magnetic resonance and scanning electron microscope determinations of the mBC demonstrated a successive grafting of phytic acid and urea to the originally porous surface. The ground mBC was blended with polylactic acid (PLA) to prepare mBC/PLA composites by extrusion and hot pressing. Mechanical strength studies showed a compromise in rigidity, which might originate from the mBC overdose and its limited miscibility with the resin. The thermogravimetric results supported the fact that the enhancement of thermal stability and flame retardancy of the composites with the mBC dosage, which showed that the mBC dosage in the PLA composites was not only lower than that of the conventional flame retardants, but also outperformed the counterparts using BC modified by inorganic phosphoric acid and urea. The mBC was prone to accelerate the earlier decomposition of the composites (30 °C lower in decomposition) and generate a continuous, dense residual carbon layer, which provides an effective shield resisting the mass and heat transfer between the combustion area and the underlying composite matrix. Only 10 wt% of mBC dosage could achieve a V-0 rating (UL94) for the composite, with a higher limiting oxygen index up to 28.3% compared to 20.7% for that of the virgin PLA; the cone colorimetric results also suggested that the flame retardancy had been greatly improved for all composites. In this work, biobased P-/N-containing bamboo biochar would be expected as a nontoxic biochar-based flame retardant that serves as green filler in polymer composites.

8.
J Environ Public Health ; 2022: 3183195, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36200081

RESUMEN

Big data improves opportunities for enhancing and improving university students' IPE. In order to improve the accessibility of IPE for university students, this study integrates big-data techniques into the IPE (Ideological and Political Education) model of university students and builds the IPE platform. This study presents the idea of user rating sparsity and employs a two-step training strategy to address the issues of user cold start and sparse data in light of the drawbacks of conventional methods. This algorithm produces a very small data structure, which saves a lot of storage space. This study also uses hybrid recommendation technology, which effectively enables platform users to select customized update resources based on their interest information. According to test results, this method's suggestion accuracy can reach 95.69%, and it has a high user rating. This demonstrates that the method is reliable and accomplishes the desired result. This paper fully utilizes mega data to improve the accessibility of IPE for university students.


Asunto(s)
Macrodatos , Relaciones Interprofesionales , Humanos , Estudiantes , Tecnología , Universidades
9.
Chem Commun (Camb) ; 58(21): 3477-3480, 2022 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-35191446

RESUMEN

A cascade strategy to synthesise gem-difluorinated 2H-furans from reactions of BrCF2CO2Et with enaminones has been described. The reactions tolerate a wide variety of functional groups under metal-free conditions. An active aminocyclopropane is proposed to be a key intermediate through the cyclopropanation of difluorocarbene with enaminones, which further triggers a regioselective C-C bond cleavage in situ to afford the corresponding gem-difluorinated 2H-furans.

11.
Psychiatry Res ; 305: 114242, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34715440

RESUMEN

The purpose of our study was to explore the value of measuring cognitive functions for predicting the conversion to psychosis in Chinese college students with a clinical high risk (CHR). A total of 115 CHR students and 99 healthy controls were enrolled. All included participants were recruited from colleges in Wuhan, China. The MATRICS Consensus Cognitive Battery was used to evaluate cognitive function. CHR individuals were followed for 2 years, and the cognitive function of CHR individuals who later converted to psychosis (CHR-C) was compared to CHR individuals who did not convert (CHR-NC). Of the 107 CHR individuals that completed the 2- year follow-up, 29 (27.1%) developed a psychotic disorder. CHR individuals demonstrated poorer performance on all cognitive function tests compared to controls. CHR-C participants exhibited poorer performance on all cognitive tests except the Trail Making Test A and Continuous Performance Test-Identical Pairs compared to CHR-NC participants. The most significant differences displayed between CHR-C and CHR-NC groups were in visual learning, working memory, and reasoning and problem solving. The degree of cognitive impairment in visual learning and working memory may be a predictive marker for individuals who are at risk of developing psychosis.


Asunto(s)
Síntomas Prodrómicos , Trastornos Psicóticos , China , Cognición , Progresión de la Enfermedad , Humanos , Trastornos Psicóticos/psicología , Estudiantes
12.
J Pharm Pharmacol ; 73(12): 1643-1651, 2021 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-34061162

RESUMEN

OBJECTIVES: Neuropathic pain (NP) represents a broad scope of various pathological ramifications of the nervous system. Remimazolam is a proved sedative in treating neuropathic pain. Considering the Bradykinin receptor's vital role and the potentials of Bradykinin receptor B1 (BDKRB1) in the neuropathic pain-signalling pathway, we nominated them as a primary target for remimazolam. METHODS: In this study, rats were injected with complete freund's adjuvant (CFA) to construct NP models in vivo. BV2 microglia cells were treated with LPS to establish NP model in vitro. qRT-PCR, ELISA, western blot and immunofluorescence were applied to determine gene expression. KEY FINDINGS: Our findings revealed that BDKRB1 was overexpressed in NP models in vivo, while R715 (an antagonist of BDKRB1) suppressed the levels of BDKRB1 and inhibited the hyperpathia induced by spinal nerve litigation surgery. Moreover, remimazolam inactivated BDKRB1 signalling via suppressing NF-κB translocation and decreased the release of pro-inflammatory cytokines. Additionally, remimazolam suppressed the translocation of NF-κB, and inhibited autophagic lysosome formation in vivo and in vitro. However, R838 (an agonist of BDKRB1) reversed the effects of remimazolam. CONCLUSIONS: Remimazolam downregulated BDKRB1, inhibited BDKRB1/RAS/MEK signalling pathway and regulated the autophagic lysosome induction, exhibiting a better outcome in the NP.


Asunto(s)
Analgésicos/farmacología , Benzodiazepinas/farmacología , Microglía/efectos de los fármacos , Neuralgia/metabolismo , Receptores de Bradiquinina/metabolismo , Analgésicos/uso terapéutico , Animales , Autofagia , Benzodiazepinas/uso terapéutico , Línea Celular , Citocinas/metabolismo , Modelos Animales de Enfermedad , Adyuvante de Freund , Hiperalgesia , Lisosomas/metabolismo , Ratones , FN-kappa B/metabolismo , Neuralgia/tratamiento farmacológico , Ratas Sprague-Dawley , Transducción de Señal
13.
AAPS PharmSciTech ; 18(8): 2889-2897, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28424978

RESUMEN

Micro-particles of 17ß-estradiol (ED) were prepared with polyvinylpyrrolidone (PVP) by in situ pH-dependent solubility technique. Products were characterized using multiple instruments, and molecular interactions between ED and PVP were explored. Powder X-ray diffraction and thermal analysis revealed crystalline ED in the micro-particles is hemihydrated. PVP was also present in the micro-particles. Laser particle size analysis and scanning electron microscopy revealed thin slice morphology, which might have resulted from the influence of PVP. Moreover, the results of contact angle, specific surface area, and dynamic vapor sorption showed that the surface properties of products were improved. These physicochemical properties of the micro-particles resulted in an obvious improvement in dissolution rate. Fourier transform infrared spectroscopy and 1H nuclear magnetic resonance revealed hydrogen bonding between ED and PVP. A method was established for the preparation of micro-particles through the addition of PVP during the reaction process.


Asunto(s)
Química Farmacéutica/métodos , Estradiol/síntesis química , Excipientes Farmacéuticos/química , Povidona/química , Rastreo Diferencial de Calorimetría/métodos , Fenómenos Químicos , Cristalización , Concentración de Iones de Hidrógeno , Microscopía Electrónica de Rastreo/métodos , Solubilidad , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Difracción de Rayos X/métodos
14.
Asian Pac J Cancer Prev ; 14(7): 4261-5, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23991987

RESUMEN

Increasing scientific evidence suggests that ribonucleotide reductase M1 (RRM1) may be a powerful predictor of survival in patients with pancreatic cancer treated with adjuvant gemcitabine-based chemotherapy after operative resection, but many existing studies have yielded inconclusive results. This meta-analysis aimed to assess the prognostic role of RRM1 in predicting survival in patients with pancreatic cancer treated with gemcitabine. An extensive literature search for relevant studies was conducted on PubMed, Embase, Web of Science, Cochrane Library, and CBM databases from their inception through May 1st, 2013. This meta-analysis was performed using the STATA 12.0 software and crude hazard ratios (HRs) with 95% confidence intervals (CIs) were calculated. Eight clinical studies were included in this meta-analysis with a total of 665 pancreatic cancer patients treated with adjuvant gemcitabine-based chemotherapy, including 373 patients in the high RRM1 expression group and 292 patients in the low RRM1 expression group. Our meta-analysis revealed that high RRM1 expression was associated with improved overall survival (OS) of pancreatic cancer patients (HR=1.56, 95%CI=0.95-2.17, P<0.001). High RRM1 expression also was linked to longer disease-free survival (DFS) than low RRM1 expression (HR=1.37, 95%CI=0.25-2.48, P=0.016). In conclusion, our meta-analysis suggests that high RRM1 expression may be associated with improved OS and DFS of pancreatic cancer patients treated with adjuvant gemcitabine-based chemotherapy. Detection of RRM1 expression may be a promising biomarker for gemcitabine response and prognosis in pancreatic cancer patients.


Asunto(s)
Antimetabolitos Antineoplásicos/uso terapéutico , Desoxicitidina/análogos & derivados , Neoplasias Pancreáticas/mortalidad , Proteínas Supresoras de Tumor/metabolismo , Desoxicitidina/uso terapéutico , Humanos , Neoplasias Pancreáticas/tratamiento farmacológico , Neoplasias Pancreáticas/metabolismo , Pronóstico , Ribonucleósido Difosfato Reductasa , Tasa de Supervivencia , Gemcitabina
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