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1.
J Environ Manage ; 358: 120909, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38642487

RESUMO

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.

2.
Int J Biol Macromol ; 265(Pt 1): 130807, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38484808

RESUMO

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.


Assuntos
Celulose , Água , Elasticidade , Compostos Radiofarmacêuticos , Interações Hidrofóbicas e Hidrofílicas
3.
Org Lett ; 26(6): 1249-1254, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38305700

RESUMO

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.

4.
Immun Inflamm Dis ; 12(2): e1132, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38415922

RESUMO

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.


Assuntos
MAP Quinases Reguladas por Sinal Extracelular , Neuralgia , Humanos , Animais , Ratos , Fator A de Crescimento do Endotélio Vascular , Fator de Crescimento Insulin-Like I/genética , Fator de Crescimento Epidérmico , Osteopontina , Interleucina-6 , Qualidade de Vida , Neuralgia/etiologia , Interleucina-1beta , Transdução de Sinais , Nervo Isquiático
5.
Int J Biol Macromol ; 258(Pt 2): 128918, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38134986

RESUMO

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.


Assuntos
Agricultura , Carvão Vegetal , Análise por Conglomerados , Poliésteres
6.
Polymers (Basel) ; 15(2)2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36679241

RESUMO

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.

7.
J Environ Public Health ; 2022: 3183195, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36200081

RESUMO

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.


Assuntos
Big Data , Relações Interprofissionais , Humanos , Estudantes , Tecnologia , Universidades
8.
Chem Commun (Camb) ; 58(21): 3477-3480, 2022 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-35191446

RESUMO

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.

10.
Psychiatry Res ; 305: 114242, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34715440

RESUMO

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.


Assuntos
Sintomas Prodrômicos , Transtornos Psicóticos , China , Cognição , Progressão da Doença , Humanos , Transtornos Psicóticos/psicologia , Estudantes
11.
J Pharm Pharmacol ; 73(12): 1643-1651, 2021 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-34061162

RESUMO

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.


Assuntos
Analgésicos/farmacologia , Benzodiazepinas/farmacologia , Microglia/efeitos dos fármacos , Neuralgia/metabolismo , Receptores da Bradicinina/metabolismo , Analgésicos/uso terapêutico , Animais , Autofagia , Benzodiazepinas/uso terapêutico , Linhagem Celular , Citocinas/metabolismo , Modelos Animais de Doenças , Adjuvante de Freund , Hiperalgesia , Lisossomos/metabolismo , Camundongos , NF-kappa B/metabolismo , Neuralgia/tratamento farmacológico , Ratos Sprague-Dawley , Transdução de Sinais
12.
AAPS PharmSciTech ; 18(8): 2889-2897, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28424978

RESUMO

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.


Assuntos
Química Farmacêutica/métodos , Estradiol/síntese química , Excipientes Farmacêuticos/química , Povidona/química , Varredura Diferencial de Calorimetria/métodos , Fenômenos Químicos , Cristalização , Concentração de Íons de Hidrogênio , Microscopia Eletrônica de Varredura/métodos , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Difração de Raios X/métodos
13.
Asian Pac J Cancer Prev ; 14(7): 4261-5, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23991987

RESUMO

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.


Assuntos
Antimetabólitos Antineoplásicos/uso terapêutico , Desoxicitidina/análogos & derivados , Neoplasias Pancreáticas/mortalidade , Proteínas Supressoras de Tumor/metabolismo , Desoxicitidina/uso terapêutico , Humanos , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/metabolismo , Prognóstico , Ribonucleosídeo Difosfato Redutase , Taxa de Sobrevida , Gencitabina
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