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1.
Biomacromolecules ; 24(12): 5698-5706, 2023 12 11.
Artigo em Inglês | MEDLINE | ID: mdl-37945526

RESUMO

The development of cell-penetrating polymers with endocytosis-independent cell uptake pathways has emerged as a prominent strategy to enhance the transfection efficiency. Inspired by the rigid α-helical structure that endows polypeptides with cell-penetrating ability, we propose that a rigid backbone can facilitate the corresponding polymer vector's performance in gene delivery by bypassing the difficult endosomal escape process. Meanwhile, the installation of aromatic domains, as a way to promote gene transfection efficiency, is employed through the construction of a poly(benzyl ether) (PBE)-based scaffold in this work. We demonstrate that the direct membrane translocation capability of the synthesized PBE contributes to its enhanced transfection performance and excellent biocompatibility profile, rendering the imidazolium-functionalized PBE scaffold with higher activity and biocompatibility. Molecular details of the PBE-lipid interaction are also revealed in molecular dynamics simulations, indicating the important roles of individual structural elements on the polymeric scaffold in the membrane penetration process.


Assuntos
Técnicas de Transferência de Genes , Polímeros , Terapia Genética , Transfecção , Peptídeos/química
2.
Ecotoxicol Environ Saf ; 252: 114646, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36791501

RESUMO

Mitophagy has distinct functions, which can lead to either protection or damage of tissues. Though current evidence indicated that NaF triggers mitophagy, the role and regulation of mitophagy in sodium fluoride (NaF)-induced liver injury still remain unclear. Therefore, we exployed the cell and mouse models and confirmed that NaF treatment activates mitophagy. Knocking down PTEN-induced putative kinase protein 1 (PINK1) expression attenuated mitophagy and increased the degree of mitochondrial impairment, oxidative stress, and apoptosis in NaF-treated HepG2 cells. In vivo experiments indicated that PINK1 deficiency weakened NaF-induced mitophagy. Moreover, PINK1-deficient mices aggravated NaF-induced hepatic mitochondrial injury, oxidative stress, and inflammation in livers, evidenced by the increased number of abnormal mitochondria, decreased adenosine triphosphate (ATP) and glutathione (GSH) levels, elevated reactive oxygen species (ROS) and malondialdehyde (MDA) content, enhanced hepatic macrophage infiltration and inflammatory cytokine levels. Notably, NaF exposure activated Nrf2 signaling both in vitro and in vivo. Nrf2 siRNA transfection blocked the upregulation of PINK1 expression and the induction of mitophagy in NaF-treated HepG2 cells. Also, ML385 (Nrf2 inhibitor) partially blocked the upregulation of PINK1 expression caused by NaF in mice livers. To sum up, the present study provided the demonstration that Nrf2/PINK1-mediated mitophagy activation offers a hepatoprotective effect by inhibiting NaF-induced mitochondrial dysfunction, oxidative stress, and inflammation.


Assuntos
Mitofagia , Fluoreto de Sódio , Camundongos , Animais , Fluoreto de Sódio/toxicidade , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Proteínas Quinases/genética , Proteínas Quinases/metabolismo , Mitocôndrias , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo , Inflamação/induzido quimicamente , Inflamação/metabolismo , Fígado/metabolismo , Glutationa/metabolismo
3.
Molecules ; 28(20)2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37894574

RESUMO

Chondroitin sulfate (CS) is a natural macromolecule polysaccharide that is extensively distributed in a wide variety of organisms. CS is of great interest to researchers due to its many in vitro and in vivo functions. CS production derives from a diverse number of sources, including but not limited to extraction from various animals or fish, bio-synthesis, and fermentation, and its purity and homogeneity can vary greatly. The structural diversity of CS with respect to sulfation and saccharide content endows this molecule with distinct complexity, allowing for functional modification. These multiple functions contribute to the application of CS in medicines, biomaterials, and functional foods. In this article, we discuss the preparation of CS from different sources, the structure of various forms of CS, and its binding to other relevant molecules. Moreover, for the creation of this article, the functions and applications of CS were reviewed, with an emphasis on drug discovery, hydrogel formation, delivery systems, and food supplements. We conclude that analyzing some perspectives on structural modifications and preparation methods could potentially influence future applications of CS in medical and biomaterial research.


Assuntos
Materiais Biocompatíveis , Sulfatos de Condroitina , Animais , Sulfatos de Condroitina/química , Polissacarídeos , Fermentação , Suplementos Nutricionais
4.
J Environ Sci (China) ; 76: 199-207, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30528010

RESUMO

Methylsiloxanes are a class of silicone compounds that have been widely used in various industrial processes and personal care products for several decades. This study investigated the spatial distribution of three cyclic methylsiloxanes (D4-D6) and twelve linear methylsiloxanes (L5-L16) in mollusks collected from seven cities along the Bohai Sea. D4-D6 (df = 71%-81%) and L8-L16 (df = 32%-40%) were frequently detectable in the mollusk samples, while L5-L7 were not found in any mollusk samples. Cyclic methylsiloxanes (D4-D6) were found in mollusks with the mean concentrations of 15.7 ±â€¯12.3 ng/g ww for D4, 24.6 ±â€¯15.8 ng/g ww for D5 and 34.0 ±â€¯23.0 ng/g ww for D6. Among the seven sampling cities, the cyclic methylsiloxanes were predominant in mollusks, with the total cyclic methylsiloxanes (sum of D4-D6, ∑CMS) accounting for 74.2%-80.7% of the total methylsiloxanes. ∑CMS along the coastline demonstrated a clear gradient, with the highest concentrations in mollusks at the sampling sites located in the western part of the Bohai Sea and the lowest concentrations in mollusks from cities located in the eastern part of the Bohai Sea. The biota-sediment accumulation factors for cyclic methylsiloxanes (D4-D6) and linear methylsiloxanes (L8-L16) were estimated as 0.42 ±â€¯0.06-0.53 ±â€¯0.06 and 0.13 ±â€¯0.03-0.19 ±â€¯0.05, respectively.


Assuntos
Monitoramento Ambiental , Moluscos/química , Oceanos e Mares , Siloxanas/análise , Siloxanas/química , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/química , Animais , China , Análise Espacial
5.
Molecules ; 23(4)2018 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-29642578

RESUMO

In this study, highly-efficient hydrolysis of bagasse into xylose and arabinose sugars (C5 sugars) was developed by microwave-assisted oxalic acid pretreatment under mild reaction conditions. The effects of acid and hydrolysis conditions on the C5 sugar yields were discussed. The results showed that oxalic acid performed better than hydrochloric acid and maleic acid, and was a promising alternative to sulfuric acid for xylose production at the same acid concentration. The maximum yields of xylose (95.7%) and arabinose (91.5%) were achieved via the microwave-assisted oxalic acid pretreatment (120 °C, 10 min, 0.4 mol/L, solid-liquid ratio of 1:50 g/mL), indicating that almost all xylan-type hemicelluloses were released from the cell wall and hydrolyzed into C5 sugars. After pretreatment, more than 90% of the cellulose in the residual bagasse was converted to glucose (92.2%) by enzymatic hydrolysis. This approach could realize the highly-efficient hydrolysis of xylan from bagasse into C5 sugars, which would enhance the enzyme hydrolysis of treated bagasse into glucose.


Assuntos
Arabinose/química , Celulose/química , Ácido Oxálico/química , Xilose/química , Parede Celular/química , Ácido Clorídrico/química , Hidrólise , Maleatos/química , Micro-Ondas
6.
Environ Sci Technol ; 51(21): 12337-12346, 2017 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-29022336

RESUMO

In one yearly cycle (2016), D4 and D5 were detected in biogas samples (n = 36, 0.105-2.33 mg/m3) from a Chinese municipal landfill, while D4-D6 were detected in influents/effluents of leachate storage pond (n = 72, < LOQ-30.5 µg/L). Mass loads of cVMS in both biogas (591-6575 mg/d) and leachate influents (659-5760 mg/d) increased from January to July (summer), and then decreased from July to December (winter). Removal experiments indicated that 1) hydrolysis and volatilization were predominant removal mechanism for D4 and D5, respectively, in leachate storage pond, responsible for their more significant removal (94.5-100%) in August; 2) indirect phototransformation (t1/2 = 25.5-87.0 days), such as hydroxylation by OH radical generated in leachates, was the predominant (50.0-75.5%) removal pathway for D6, which led to the largest removal efficiencies (65.2-73.7%) in June, the month with the largest sun light intensity and highest photosensitizer (e.g., Fe2+ and NO3-) concentrations. Monohydroxylated products of D5 and D6, D4TOH and D5TOH, were detected in leachate effluents (39.6-187 ng/L) during May-July. Compared to D5 and D6, volatilization half-lives of D4TOH (86.3 days) and D5TOH (177 days) in leachates were 2.9 and 1.4 times longer, while their hydrolysis half-lives (7.50 days for D4TOH and 21.5 days for D5TOH) were 7.1 and 10 times shorter, respectively.


Assuntos
Instalações de Eliminação de Resíduos , Poluentes Químicos da Água , Hidroxilação , Siloxanas , Volatilização
7.
Environ Sci Technol ; 50(23): 12732-12741, 2016 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-27648832

RESUMO

Simulated experiments indicated that chlorinated volatile methylsiloxanes, detected by Q-TOF GC/MS, could be generated in a pulp-bleaching process, where poly(dimethylsiloxane)s fluids with volatile methylsiloxanes as impurities and molecular chlorine were used as a defoamer and bleaching agent, respectively. In the producing processes of one papermaking factory, the mean total concentrations of monochlorinated D4, D5, and D6, i.e., D3D(CH2Cl), D4D(CH2Cl), and D5D(CH2Cl), were 0.0430-287 µg/L in aqueous samples, while they were 0.0329-270 µg/g in solid samples. In the coupled papermaking-wastewater treatment processes, D3D(CH2Cl), D4D(CH2Cl), and D5D(CH2Cl) were detected in all water (0.113-8.68 µg/L) and solid samples (0.888-26.2 µg/g), with solid-water partition values (468-3982 L/kg) 1.08-4.82 times higher than those of their corresponding nonchlorinated analogs. The removing efficiencies of D3D(CH2Cl)-D5D(CH2Cl) in the whole wastewater treatment processes were 77.1-81.6%, and sorption to sludge (35.7-74.1%) and removal in the primary clarifier (7.19-32.5%) had major contributions to their total removal. Elimination experiments showed that 1) hydrolysis half-lives of D3D(CH2Cl)-D5D(CH2Cl) (0.9-346 h) in the primary clarifier (pH = 7.8-9.2) were 2.16-3.60 times shorter than those of their nonchlorinated analogs; 2) D3D(CH2Cl)-D5D(CH2Cl) were hardly degraded in oxic sludge treatment process, and their volatilization half-lives (7.38-21.1 h) in oxic sludge were 1.21-1.50 times longer than those of their nonchlorinated analogs.


Assuntos
Águas Residuárias/química , Poluentes Químicos da Água , Esgotos/química , Siloxanas/química , Volatilização , Eliminação de Resíduos Líquidos
8.
Int J Biol Macromol ; 263(Pt 2): 130251, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38368991

RESUMO

Compared with traditional papermaking, foam forming is a new papermaking technology that uses foam instead of water to disperse fibres, which can effectively solve the problem of poor evenness of ceramic paper, but the instability of foam itself affects the application of foam forming technology. Herein, a highly stable foaming agent for foam forming technology was prepared via physical reaction of lauryl dimethyl amine oxide (OB-2) with filamentous nanocellulose (cellulose nanofiber (CNF-C) and bacterial cellulose (BC)). Then, the quartz paper was prepared by foam forming technology. Firstly, hydrogen bond interactions between hydroxyl groups of the filamentous nanocellulose and hydrophilic moieties on OB-2 enabled the formation of a 3D nanonetwork layer on the surface of the bubble, which extended the half-life of the bubble and effectively prevented the bubble from bursting or coalescing. Then, the foam was extruded and cracked, and the filamentous nanocellulose was retained on the quartz fibres to prepare filamentous nanocellulose/quartz fibre paper by foam forming technology. The quartz paper exhibited excellent evenness and mechanical properties. In conclusion, the research of foam forming technology is of great significance to the application and development of special paper.


Assuntos
Nanofibras , Quartzo , Celulose/química , Nanofibras/química , Tensoativos , Água
9.
Food Chem ; 453: 139680, 2024 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-38788648

RESUMO

Hydrophobic coatings have wide applications, but face challenges in food flexible packaging in terms of poor adhesion and inadequate wear resistance. Health hazards and poor adhesion drive the search for novel hydrophobic coatings substitutes. Here, we introduced rationally synthesized carnauba wax-SiO2 microspheres as a component to composite polyethylene (PE) film construction, and created a wear-resistant hydrophobic composite PE film via the blown film technique. The resultant hydrophobic composite film demonstrated an enhanced water contact angle from 86° to above 100°, coupled with favorable mechanical properties such as wear resistance, tensile strength and effective barrier performance against water vapor and oxygen. Upon implementation in the preservation of a Cantonese delicacy, Chaoshan fried shrimp rolls, it was observed that at 25 °C, the carnauba wax-SiO2-PE composite packaging film extended the shelf life of the product by 3 days compared to pure PE film.


Assuntos
Embalagem de Alimentos , Conservação de Alimentos , Interações Hidrofóbicas e Hidrofílicas , Polietileno , Ceras , Polietileno/química , Embalagem de Alimentos/instrumentação , Animais , Ceras/química , Conservação de Alimentos/métodos , Conservação de Alimentos/instrumentação , Resistência à Tração , Dióxido de Silício/química , Penaeidae/química
10.
Biotechnol Genet Eng Rev ; : 1-11, 2023 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-37078549

RESUMO

To investigate the value of bracketless invisible orthodontic treatment combined with restoration in patients with anterior esthetic restoration. Sixty-two patients requiring esthetic restoration of anterior teeth admitted to our hospital from May 2019 to August 2022 were selected and divided into observation group and control group according to random number table, with 31 cases in each group. The patients in the control group were treated with repair, while patients in the observation group were treated with bracketless invisible correction treatment combined with repair. The patients in both groups were treated with repair. After 2 weeks, dental esthetics, periodontal index related parameters, patients' esthetic acceptance of restorations, and satisfaction were compared. The aesthetic restoration effect of teeth in the observation group was significantly better than that in the control group after treatment, and the difference was statistically significant (P < 0.05). There was no significant difference in GI, SPD, PLI, and SBI levels before and after treatment between the two groups (P > 0.05). The acceptance rate of prosthesis aesthetics in the observation group was 100.00%, which was significantly higher than that in the control group (83.87%), and the difference was statistically significant (P < 0.05). The satisfaction scores of restoration color, shape and coordination with adjacent teeth in the observation group were higher than those in the control group, and the differences were statistically significant (P < 0.05). Compared with simple restorative treatment, combined with bracketless invisible orthodontic treatment helps to further improve the esthetic restoration effect of anterior teeth, has less impact on the periodontal health of patients, and has higher patient acceptance and satisfaction.

11.
Water Res ; 220: 118612, 2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35613483

RESUMO

Membrane separation is an effective solution for pollutant removal, however, achieving high permeability and antifouling ability remains a pressing challenge for its widespread application. In this study, a novel method of coating flat ceramic membranes (CMs) with a conductive film (Sb-SnO2) was developed to enhance the filtration and antifouling performance of CMs when the membrane filtration was coupled with electrocoagulation. After comparing the parameters, including the film sheet resistance and pure water flux, with those of other coating methods (i.e., gel coating and immersion hydrolysis), a well-fixed conductive coating with optimal permeability and stability was generated using spray pyrolysis with a substrate ceramic membrane surface temperature of 475 °C, precursor concentration of 0.5 M (calculate as SnO2), and spraying amount of 50 mL (120 cm2), during membrane modification. Batch filtration experiments using wastewater from the mechanical industry demonstrated that the conductive ceramic membrane (CCM) cathode integrated with electrocoagulation at an electric field of 2.8 V/cm (3.0 mA/cm2) achieved permeate fluxes that were 0.34, 0.70, 0.75 and 1.41 times higher than those of sole CM separation after four cycles. Moreover, the membrane separation process was dominated by the standard pore-blocking model, and its correlation coefficient decreased with the exertion of the electric field, indicating that membrane filtration fouling changed from irreversible to reversible. This CCM combined with electrocoagulation exhibited significant potential for alleviating membrane fouling and widespread application, and could act as a promising technology for industrial wastewater treatment.


Assuntos
Águas Residuárias , Purificação da Água , Cerâmica , Eletrocoagulação , Filtração/métodos , Membranas Artificiais , Águas Residuárias/química , Purificação da Água/métodos
12.
Int J Biol Macromol ; 132: 978-986, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-30880050

RESUMO

The effects of nano-ZnO and nano-SiO2 on the properties of PVA/xylan composite films were investigated in this work. Results showed that nano-ZnO and nano-SiO2 could effectively improve the mechanical strength, moisture and oxygen barrier properties and surface hydrophobic property of the composite films. The results of FTIR and XRD indicated the interaction of hydrogen bonds between nanoparticles and PVA and xylan. When the contents of nano-ZnO and nano-SiO2 in the composite films were 3%, the tensile strength was increased to 20.4 MPa and 22.5 MPa, respectively, while water vapor permeability (3.14 and 3.03 × 10-11 g·m-1·s-1·Pa-1) and oxygen permeability (5.28 and 5.003 cm3·m-2·24 h-1·0.1 MPa-1) reached the minima. With the increase of nano-ZnO and nano-SiO2 dosage, the solubility of composite films was increased. When the contents of nano-ZnO and nano-SiO2 were 3% and 4%, respectively, the contact angles of the films was increased up to 101° and 78°. Besides, the composite films with nano-ZnO exhibited UV shielding performance, whereas the ones with nano-SiO2 had similar UV light-transparency to the pure PVA/xylan composite films.


Assuntos
Nanocompostos/química , Nanopartículas/química , Álcool de Polivinil/química , Dióxido de Silício/química , Xilanos/química , Óxido de Zinco/química , Oxigênio/química , Permeabilidade , Solubilidade , Vapor , Propriedades de Superfície , Temperatura , Resistência à Tração
13.
Environ Sci Pollut Res Int ; 25(5): 4803-4810, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29198030

RESUMO

Bituminous coal-based magnetic activated carbon (MAC) was prepared, characterized, and used successfully for removal of cyclic volatile methylsiloxanes (cVMSs) from treated landfill leachate. Batch adsorption studies were performed at different adsorption dosages and contact times. With adsorptive dosage of 0.75 g/L and contact time of 60 min, the removal efficiencies achieved by MAC for octamethylcyclotetrasiloxane (D4), decamethylcyclopentasiloxane (D5), and dodecamethylcyclohexasiloxane (D6) are 100, 82.8, and 71.4%, respectively. The specific magnetization coefficients of MAC before and after adsorption are 4.6 × 10-7 and 5.2 × 10-7 m3/kg, between 1.26 × 10-7 and 3.8 × 10-5 m3/kg, which suggests that MAC can be recycled by the high-intensity magnetic separators.


Assuntos
Carvão Vegetal/química , Carvão Mineral , Óxido Ferroso-Férrico/química , Siloxanas/análise , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Adsorção , Alcatrão/química
14.
Sci Rep ; 7(1): 11248, 2017 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-28900140

RESUMO

Seed germination behavior is an important factor in the distribution of species. Many studies have shown that germination is controlled by phylogenetic constraints, however, it is not clear whether phylogenetic constraints or environmental cues explain seed germination of a genus from a common ancestor. In this study, seed germination under different temperature- and water-regimes [induced by different osmotic potentials of polyethylene glycol (PEG)] was investigated in the phylogenetically-related Caragana species that thrive in arid, semiarid, semihumid and humid environments. The results showed that the final percentage germination (FPG) decreased from 95% in species from arid habitats to 0% in species from humid habitats, but with no significant phylogenetic signal. Rather, the response of seed germination to temperature and PEG varied greatly with species from arid to humid habitats and was tightly linked to the ecological niche of the species, their seed coat structure and abscisic acid concentration. The findings are not consistent with the hypothesis that within a family or a genus, seed germination strategies can be a stable evolutionary trait, thus constraining interspecific variation, but the results clearly show that seed germination of Caragana species distributed across a range of habitats has adapted to the environment of that habitat.


Assuntos
Caragana/crescimento & desenvolvimento , Sinais (Psicologia) , Exposição Ambiental , Germinação , Sementes/crescimento & desenvolvimento , Caragana/genética , Clima , Umidade , Pressão Osmótica , Filogenia , Polietilenoglicóis/metabolismo , Sementes/genética , Temperatura
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