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1.
Molecules ; 27(11)2022 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-35684333

RESUMO

The atomic picture of cellulose dissolution in alkali/urea aqueous solution is still not clear. To reveal it, we use trehalose as the model molecule and total scattering as the main tool. Three kinds of alkali solution, i.e., LiOH, NaOH and KOH are compared. The most probable all-atom structures of the solution are thus obtained. The hydration shell of trehalose has a layered structure. The smaller alkali ions can penetrate into the glucose rings around oxygen atoms to form the first hydration layer. The larger urea molecules interact with hydroxide groups to form complexations. Then, the electronegative complexation can form the second hydration layer around alkali ions via electrostatic interaction. Therefore, the solubility of alkali aqueous solution for cellulose decreases with the alkali cation radius, i.e., LiOH > NaOH > KOH. Our findings are helpful for designing better green solvents for cellulose.


Assuntos
Trealose , Ureia , Álcalis , Celulose/química , Nêutrons , Hidróxido de Sódio/química , Solubilidade , Ureia/química , Água/química
2.
Int J Biometeorol ; 60(9): 1423-37, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26813883

RESUMO

Water shortage threatens agricultural sustainability in many arid and semiarid areas of the world. It is unknown whether improved water conservation practices can be developed to alleviate this issue while increasing crop productivity. In this study, we developed a "double mulching" system, i.e., plastic film coupled with straw mulch, integrated together with intensified strip intercropping. We determined (i) the responses of soil evaporation and moisture conservation to the integrated double mulching system and (ii) the change of soil temperature during key plant growth stages under the integrated systems. Experiments were carried out in northwest China in 2009 to 2011. Results show that wheat-maize strip intercropping in combination with plastic film and straw covering on the soil surface increased soil moisture (mm) by an average of 3.8 % before sowing, 5.3 % during the wheat and maize co-growth period, 4.4 % after wheat harvest, and 4.9 % after maize harvest, compared to conventional practice (control). The double mulching decreased total evapotranspiration of the two intercrops by an average of 4.6 % (P < 0.05), compared to control. An added feature was that the double mulching system decreased soil temperature in the top 10-cm depth by 1.26 to 1.31 °C in the strips of the cool-season wheat, and by 1.31 to 1.51 °C in the strips of the warm-season maize through the 2 years. Soil temperature of maize strips higher as 1.25 to 1.94 °C than that of wheat strips in the top 10-cm soil depth under intercropping with the double mulching system; especially higher as 1.58 to 2.11 °C under intercropping with the conventional tillage; this allows the two intercrops to grow in a well "collaborative" status under the double mulching system during their co-growth period. The improvement of soil moisture and the optimization of soil temperature for the two intercrops allow us to conclude that wheat-maize intensification with the double mulching system can be used as an effective farming model in alleviating water shortage issues experiencing in water shortage areas.


Assuntos
Agricultura/métodos , Conservação dos Recursos Naturais , Solo/química , Água/análise , China , Clima , Caules de Planta , Plásticos , Temperatura , Triticum/crescimento & desenvolvimento , Volatilização , Zea mays/crescimento & desenvolvimento
3.
J Control Release ; 366: 621-636, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38215986

RESUMO

Semaglutide is the first oral glucagon-like peptide-1 (GLP-1) analog commercially available for the treatment of type 2 diabetes. In this work, semaglutide was incorporated into poly(lactic-co-glycolic acid)-poly(ethylene glycol) (PLGA-PEG) nanoparticles (NPs) to improve its delivery across the intestinal barrier. The nanocarriers were surface-decorated with either a peptide or an affibody that target the human neonatal Fc receptor (hFcRn), located on the luminal cell surface of the enterocytes. Both ligands were successfully conjugated with the PLGA-PEG via maleimide-thiol chemistry and thereafter, the functionalized polymers were used to produce semaglutide-loaded NPs. Monodisperse NPs with an average size of 170 nm, neutral surface charge and 3% of semaglutide loading were obtained. Both FcRn-targeted NPs exhibited improved interaction and association with Caco-2 cells (cells that endogenously express the hFcRn), compared to non-targeted NPs. Additionally, the uptake of FcRn-targeted NPs was also observed to occur in human intestinal organoids (HIOs) expressing hFcRn through microinjection into the lumen of HIOs, resulting in potential increase of semaglutide permeability for both ligand-functionalized nanocarriers. Herein, our study demonstrates valuable data and insights that the FcRn-targeted NPs has the capacity to promote intestinal absorption of therapeutic peptides.


Assuntos
Diabetes Mellitus Tipo 2 , Peptídeos Semelhantes ao Glucagon , Lactatos , Nanopartículas , Polietilenoglicóis , Recém-Nascido , Humanos , Células CACO-2 , Peptídeos , Receptores Fc
4.
Funct Plant Biol ; 512024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38669458

RESUMO

To improve light harvest and plant structural support under low light intensity, it is useful to investigate the effects of different ratios of blue light on petiole and stem growth. Two true leaves of soybean seedlings were exposed to a total light intensity of 200µmolm-2 s-1 , presented as either white light or three levels of blue light (40µmolm-2 s-1 , 67µmolm-2 s-1 and 100µmolm-2 s-1 ) for 15days. Soybean petioles under the low blue light treatment upregulated expression of genes relating to lignin metabolism, enhancing lignin content compared with the white light treatment. The low blue light treatment had high petiole length, increased plant height and improved petiole strength arising from high lignin content, thus significantly increasing leaf dry weight relative to the white light treatment. Compared with white light, the treatment with the highest blue light ratio reduced plant height and enhanced plant support through increased cellulose and hemicellulose content in the stem. Under low light intensity, 20% blue light enhanced petiole length and strength to improve photosynthate biomass; whereas 50% blue light lowered plants' centre of gravity, preventing lodging and conserving carbohydrate allocation.


Assuntos
Luz Azul , Celulose , Glycine max , Lignina , Caules de Planta , Celulose/metabolismo , Glycine max/crescimento & desenvolvimento , Glycine max/efeitos da radiação , Lignina/metabolismo , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/efeitos da radiação , Caules de Planta/crescimento & desenvolvimento , Caules de Planta/efeitos da radiação
5.
Adv Healthc Mater ; 13(20): e2304675, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38688026

RESUMO

The mitochondrial enzyme arginase-2 (Arg-2) is implicated in the pathophysiology of contrast-induced acute kidney injury (CI-AKI). Therefore, Arg-2 represents a candid target for CI-AKI prevention. Here, layer-by-layer (LbL) assembled renal-targeting polymeric nanoparticles are developed to efficiently deliver small interfering RNA (siRNA), knockdown Arg-2 expression in renal tubules, and prevention of CI-AKI is evaluated. First, near-infrared dye-loaded poly(lactic-co-glycolic acid) (PLGA) anionic cores are electrostatically coated with cationic chitosan (CS) to facilitate the adsorption and stabilization of Arg-2 siRNA. Next, nanoparticles are coated with anionic hyaluronan (HA) to provide protection against siRNA leakage and shielding against early clearance. Sequential electrostatic layering of CS and HA improves loading capacity of Arg-2 siRNA and yields LbL-assembled nanoparticles. Renal targeting and accumulation is enhanced by modifying the outermost layer of HA with a kidney targeting peptide (HA-KTP). The resultant kidney-targeting and siRNA loaded nanoparticles (PLGA/CS/HA-KTP siRNA) exhibit proprietary accumulation in kidneys and proximal tubular cells at 24 h post-tail vein injection. In iohexol-induced in vitro and in vivo CI-AKI models, PLGA/CS/HA-KTP siRNA delivery alleviates oxidative and nitrification stress, and rescues mitochondrial dysfunction while reducing apoptosis, thereby demonstrating a robust and satisfactory therapeutic effect. Thus, PLGA/CS/HA-KTP siRNA nanoparticles offer a promising candidate therapy to protect against CI-AKI.


Assuntos
Injúria Renal Aguda , Arginase , Meios de Contraste , Nanopartículas , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , RNA Interferente Pequeno , Nanopartículas/química , Injúria Renal Aguda/induzido quimicamente , Injúria Renal Aguda/prevenção & controle , Injúria Renal Aguda/metabolismo , Animais , RNA Interferente Pequeno/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Meios de Contraste/química , Camundongos , Arginase/metabolismo , Arginase/genética , Quitosana/química , Técnicas de Silenciamento de Genes , Rim/metabolismo , Rim/efeitos dos fármacos , Rim/patologia , Ácido Hialurônico/química , Masculino , Humanos , Ácido Láctico/química , Ácido Poliglicólico/química , Nanopartículas em Multicamadas
6.
Adv Sci (Weinh) ; 11(32): e2404171, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39031840

RESUMO

Hepatic ischemia-reperfusion injury (HIRI) is a prevalent issue during liver resection and transplantation, with currently no cure or FDA-approved therapy. A promising drug, Cyclosporin A (CsA), ameliorates HIRI by maintaining mitochondrial homeostasis but has systemic side effects due to its low bioavailability and high dosage requirements. This study introduces a biomimetic CsA delivery system that directly targets hepatic lesions using mesenchymal stem cell (MSC) membrane-camouflaged liposomes. These hybrid nanovesicles (NVs), leveraging MSC-derived proteins, demonstrate efficient inflammatory chemotaxis, transendothelial migration, and drug-loading capacity. In a HIRI mouse model, the biomimetic NVs accumulated at liver injury sites entered hepatocytes, and significantly reduced liver damage and restore function using only one-tenth of the CsA dose typically required. Proteomic analysis verifies the protection mechanism, which includes reactive oxygen species inhibition, preservation of mitochondrial integrity, and reduced cellular apoptosis, suggesting potential for this biomimetic strategy in HIRI intervention.


Assuntos
Ciclosporina , Modelos Animais de Doenças , Lipossomos , Células-Tronco Mesenquimais , Traumatismo por Reperfusão , Animais , Ciclosporina/farmacologia , Ciclosporina/administração & dosagem , Traumatismo por Reperfusão/prevenção & controle , Camundongos , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/efeitos dos fármacos , Biomimética/métodos , Fígado/metabolismo , Fígado/efeitos dos fármacos , Sistemas de Liberação de Medicamentos/métodos , Masculino , Camundongos Endogâmicos C57BL
7.
Bioresour Technol ; 373: 128752, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36804856

RESUMO

The fermented corn stover residues are abundant renewable lignin-rich bioresources that show great potential to produce aromatic phenols. However, selective catalytic hydrogenolysis of this residual material still remains challenge to obtain high yields. Herein, a novel strategy to produce monophenolic compounds from the fermented stover over a commercial Pd/C catalyst was proposed. Taking the reaction temperature as the key variable, the highest monomer yield was 28.5 wt% at 220 °C in compaction with that of the pristine corn stover (22.8 wt%). The enhanced monophenol yield was due to the higher contents of lignin and less recalcitrance in the fermented stover. Moreover, the van Krevelen diagram revealed a slight selective CO bond scission of lignin macromolecular during fermentation as well as the dehydration and deoxygenation in hydrogenolysis reaction. Overall, this work opens a new avenue for the valorization of lignin through reductive catalytic fractionation of agricultural wastes.


Assuntos
Lignina , Zea mays , Lignina/química , Zea mays/química , Catálise , Fracionamento Químico , Fenóis
8.
Food Chem ; 404(Pt A): 134371, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36244073

RESUMO

For monitoring of the residual of parathion pesticide in food, herein, a sensitive and reliable electrochemical immunosensor based on cross-linked polyvinyl alcohol/citric acid nanofiber membrane (PVA/CA NFM) and horseradish peroxidase labeled anti-parathion nanobody was constructed. Firstly, the cross-linked PVA/CA NFM with extra-high surface area and uniform morphology was prepared and characterized. Then, the immunosensor was assembled and its analytical performances were evaluated. It exhibited high specificity and sensitivity to parathion with the liner range and limit of detection being 0.01-100 ng/mL and 2.26 pg/mL, respectively. Moreover, the biosensor kept almost 75% of its initial activity after regenerating 4 times, and remained 85% after 9 weeks of storage. Finally, the average recoveries from food samples were 96.20%-114.61% with the coefficient of variation being 1.06%-5.28%, which was correlate well with UPLC (R2 = 0.9964). Therefore, the sensor was demonstrated to be a feasible alternative for sensitive assay of parathion.


Assuntos
Técnicas Biossensoriais , Nanocompostos , Paration , Técnicas Eletroquímicas , Limite de Detecção , Imunoensaio , Nanocompostos/química , Álcool de Polivinil/química , Ouro/química
9.
Sci Total Environ ; 826: 154220, 2022 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-35240178

RESUMO

Modern agricultural production is an energy- and carbon-intensive system. Enhancing energy and carbon efficiencies and reducing carbon footprints are important issues of sustainable development in modern agriculture. This study aimed to comprehensively assess energy and carbon budgeting and carbon footprints in wheat-maize intercropping, monoculture maize, and monoculture wheat with straw and plastic film management approaches, as based on a field experiment conducted in northwestern China. The results showed that intercropping had a greater grain yield by 12.8% and 131.0% than monoculture maize and wheat, respectively. Intercropping decreased energy and carbon inputs, increased energy and carbon outputs, thus improving energy and carbon efficiency, compared to monoculture maize. Intercropping reduced carbon footprint (CF) and yield-scale on the carbon footprint (CFy) via decreasing soil CO2 equivalent emissions over monoculture maize. For the intercropping treatments, NTSMw/NTm (no-tillage with straw mulching and residual plastic film re-mulching) and NTSSw/NTm (no-tillage with straw standing and residual plastic film re-mulching) treatments increased grain yields by 14.9% and 13.8% over CTw/CTm (conventional tillage with no straw returning and annual new plastic film mulching). The lower energy inputs and higher energy outputs were observed in NTSMw/NTm and NTSSw/NTm treatments, thus, NTSMw/NTm and NTSSw/NTm had greater energy use efficiency by 36.9% and 34.9% than CTw/CTm. NTSMw/NTm and NTSSw/NTm treatments decreased carbon inputs and increased carbon outputs, thus improving carbon efficiency by 56.6% and 53.1%, compared to CTw/CTm. NTSMw/NTm and NTSSw/NTm treatments decreased CF by 16.8% and 14.3%, and decreased CFy by 27.6% and 24.8% compared to CTw/CTm, respectively, because of the decrease in soil CO2 equivalent emissions. Our study indicated that system productivity, as well as energy and carbon efficiencies were enhanced, and carbon footprints were reduced by NTSMw/NTm and NTSSw/NTm treatments, and NTSMw/NTm had a more robust effect, indicating this treatment is the most sustainable cropping system in arid areas.


Assuntos
Triticum , Zea mays , Agricultura/métodos , Carbono , Dióxido de Carbono , Pegada de Carbono , China , Plásticos , Solo
10.
Talanta ; 241: 123240, 2022 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-35065346

RESUMO

Molecularly imprinted polymers (MIPs) are artificial chemical receptors, and can recognize template molecules with a high selectivity and affinity. As "antibody mimics", MIPs have been widely studied in various fields. However, the general applicability of MIPs is limited by the type of functional monomers. Herein, we developed caffeic acid (CA, a natural polyphenol) as novel a functional monomer. An innovative poly(caffeic acid)-coated molecularly imprinted magnetic nanoparticles (PCA-MIMN) with transferrin (TRF) as a model glycoprotein template was fabricated by autoxidation of CA with hexamethylenediamine (HMDA) in an aerobic environment as imprinted layer. The successful fabrication of PCA-MIMN was proved in detail by diversified characterization. The PCA-MIMN exhibited not only outstanding binding affinity and specificity for target glycoprotein, but also excellent hydrophilicity due to the externally generous hydrophilic groups. To evaluate the preeminent performance, the PCA-MIMN was linked with pH-triggered allochroic-graphene oxide (AGO), which was used for determination of TRF in real samples. The proposed PCA-MIMN linked AGO strategy exhibited ultrahigh sensitivity with limit of detection of 0.38 pg mL-1 for TRF. Finally, the proposed strategy was successfully applied in determination of TRF in spiked human serum sample with recovery and relative standard deviation in the range of 97.2%-103.9% and 4.6%-5.8%, respectively. This work demonstrates that the "autoxidation of CA with HMDA" may be a universal tool for synthesis of highly specific MIPs, and the type of functional monomers will increase exponentially due to the presence of numerous polyphenols in nature.


Assuntos
Nanopartículas de Magnetita , Impressão Molecular , Adsorção , Ácidos Cafeicos , Glicoproteínas , Humanos , Nanopartículas de Magnetita/química , Polímeros/química
11.
Huan Jing Ke Xue ; 43(8): 3990-3997, 2022 Aug 08.
Artigo em Zh | MEDLINE | ID: mdl-35971697

RESUMO

The pollution level, emission characteristics, and emission factors of PCDD/Fs from a number of steel plants were investigated in a particular province of China. The results showed that the concentration of PCDD/Fs was at a low level and decreased by 1-2 orders of magnitude compared with that in 2005-2019. In detail, the concentrations of PCDD/Fs ranged from 0.003-0.557 ng·m-3(I-TEQ), and the mean value was 0.165 ng·m-3 for the sintering process. Moreover, the concentrations of PCDD/Fs ranged from 0.006 to 0.057 ng·m-3, and the mean value was 0.025 ng·m-3 for the electric furnace process. In addition, the concentration of PCDD/Fs in the iron and steel industry from 2005 to 2020 increased first and then decreased, especially after the implementation of the new emission standard and the ultra-low emission control of conventional pollutants such as smoke, showing a significant decline. The results of fingerprint analysis showed that 2,3,7,8-TCDF was the largest congener contributing to the mass concentration, and lower chlorinated PCDFs were increased. This result differed from those of previous studies in which highly chlorinated PCDFs and PCDDs dominated, indicating that the generation source of PCDD/Fs had changed. The congener and isomer profiles of PCDD/Fs in flue gas from the sintering process were similar to those in the flue gas from the electric furnace process. Additionally, showing the characteristics of the typical high-temperature thermal process, the de novo synthesis may be the dominant mechanism of formation of PCDD/Fs in the sintering process and electric furnace process. The emission factor was 0.003-0.5 µg·t-1 (I-TEQ), and the average emission factor was (0.18±0.22) µg·t-1 for the sintering process. The emission factor was 0.04-0.5 µg·t-1, and the average emission factor was (0.27±0.23) µg·t-1 for the electric furnace process. These values were far lower than those of the standard toolkit for identification and quantification of dioxin and furan emissions released by UNEP in 2013 and the emission factors in the dioxin emission inventory of China in 2004. It is suggested that the emission factors of PCDD/Fs in the iron and steel industry of China should be studied and updated.


Assuntos
Poluentes Atmosféricos , Dioxinas , Dibenzodioxinas Policloradas , Poluentes Atmosféricos/análise , Dibenzofuranos/análise , Dibenzofuranos Policlorados/análise , Dioxinas/análise , Monitoramento Ambiental , Incineração , Ferro/análise , Dibenzodioxinas Policloradas/análise , Aço/análise
12.
ACS Appl Mater Interfaces ; 13(28): 32690-32702, 2021 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-34229434

RESUMO

The synergistic nanotheranostics of reactive oxygen species (ROS) augment or phototherapy has been a promising method within synergistic oncotherapy. However, it is still hindered by sophisticated design and fabrication, lack of a multimodal synergistic effect, and hypoxia-associated poor photodynamic therapy (PDT) efficacy. Herein, a kind of porous shuttle-shape platinum (IV) methylene blue (Mb) coordination polymer nanotheranostics-loaded 10-hydroxycamptothecin (CPT) is fabricated to address the abovementioned limitations. Our nanoreactors possess spatiotemporally controlled O2 self-supply, self-sufficient singlet oxygen (1O2), and outstanding photothermal effect. Once they are taken up by tumor cells, nanoreactors as a cascade catalyst can efficiently catalyze degradation of the endogenous hydrogen peroxide (H2O2) into O2 to alleviate tumor hypoxia. The production of O2 can ensure enhanced PDT. Subsequently, under both stimuli of external red light irradiation and internal lysosomal acidity, nanoreactors can achieve the on-demand release of CPT to augment in situ mitochondrial ROS and highly efficient tumor ablation via phototherapy. Moreover, under the guidance of near-infrared (NIR) fluorescent imaging, our nanoreactors exhibit strongly synergistic potency for treatment of hypoxic tumors while reducing damages against normal tissues and organs. Collectively, shuttle-shape platinum-coordinated nanoreactors with augmented ROS capacity and enhanced phototherapy efficiency can be regarded as a novel tumor theranostic agent and further promote the research of synergistic oncotherapy.


Assuntos
Antineoplásicos/uso terapêutico , Camptotecina/análogos & derivados , Portadores de Fármacos/química , Nanoestruturas/química , Neoplasias/tratamento farmacológico , Hipóxia Tumoral/efeitos dos fármacos , Animais , Antineoplásicos/química , Camptotecina/química , Camptotecina/uso terapêutico , Catálise/efeitos da radiação , Linhagem Celular Tumoral , Portadores de Fármacos/efeitos da radiação , Liberação Controlada de Fármacos , Feminino , Humanos , Peróxido de Hidrogênio/química , Peróxido de Hidrogênio/metabolismo , Luz , Azul de Metileno/análogos & derivados , Azul de Metileno/efeitos da radiação , Camundongos Endogâmicos BALB C , Nanoestruturas/efeitos da radiação , Neoplasias/metabolismo , Oxigênio/metabolismo , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/uso terapêutico , Terapia Fototérmica , Platina/química , Platina/efeitos da radiação , Polímeros/síntese química , Polímeros/química , Polímeros/efeitos da radiação , Porosidade , Oxigênio Singlete/metabolismo , Nanomedicina Teranóstica
13.
Int J Pharm ; 594: 120184, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33340597

RESUMO

D-a-tocopheryl polyethylene glycol succinate (TPGS) as a FDA-approved safe adjuvant has shown an excellent application in the targeting delivery of antitumor drugs and overcoming multidrug resistance. Beside, TPGS can result in apoptogenic activity toward many tumor types because it can induce mitochondrial dysfunction. Therefore, TPGS can serve as an antineoplastic agent. However, the current research on the selective antitumor activity of TPGS is ignored. To reveal the issue, herein we develop a mitochondria-targeting drug-free TPGS nanomicelles with the hydrodynamic diameter of about 100 nm and outstanding serum stability by weak interaction-driven self-assembly of the amphiphilic TPGS polymer. Moreover, such drug-free TPGS nanomicelles intravenously injected into tumor-bearing mice exhibit long blood circulation time, superior tumor enrichment, and inhibit the tumor growth via inducing excessive reactive oxygen species (ROS) generation within tumor cells. Further in vitro and in vivo researches jointly demonstrate that drug-free TPGS nanomicelles have more significant antitumor effect on HeLa cells compared with that of other tumor cells. On the contrary, drug-free TPGS nanomicelles display the low toxicity toward normal cells and tissues. Taken together, these new findings confirm that TPGS drug-free nanomicelles represent simple, multifunctional, safe, and efficient antineoplastic agents, which can be expected to bring new light on the development of drug-free polymers for tumor therapy.


Assuntos
Antineoplásicos , Polietilenoglicóis , Animais , Antineoplásicos/farmacologia , Morte Celular , Linhagem Celular Tumoral , Células HeLa , Humanos , Camundongos , Micelas , Mitocôndrias , Espécies Reativas de Oxigênio , Vitamina E
14.
Adv Mater ; 33(18): e2100849, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33797149

RESUMO

Gene silencing holds promise for cancer therapeutics because of its potential to inhibit genes involved in tumor development. However, gene silencing is still restricted by its limited efficacy and safety. Nanoscale coordination polymers (CPs) emerge as promising nanocarriers for gene delivery, but their responsiveness and potential therapeutic properties have rarely been explored simultaneously. Here, multifunctional ultrathin 2D nanosheets of Cu(I) 1,2,4-triazolate CP with a thickness of 4.5 ± 0.8 nm are synthesized using a bottom-up method. These CP nanosheets can act as both an effective DNAzyme nanocarrier for gene therapy and an intrinsic photosensitizer for hypoxia-tolerant type I photodynamic therapy (PDT), which is ascribed to the Fenton-like reaction. Because of the glutathione (GSH)-responsiveness of the CP nanosheets, DNAzyme-loaded CP nanosheets exhibit excellent cancer-cell-targeting gene silencing of the early growth response factor-1 (EGR-1), with messenger RNA inhibited by 84% in MCF-7 (human breast cancer cells) and only 6% in MCF-10A (normal human mammary epithelial cells). After tail intravenous injection into MCF-7-tumor-bearing mice, the CP nanosheets loaded with chlorin-e6-modified DNAzyme under photoirradiation show a high antitumor efficacy (88.0% tumor regression), demonstrating a promising therapeutic platform with efficient and selective gene silencing and PDT of cancer.


Assuntos
Cobre/química , Nanoestruturas/química , Fotoquimioterapia , Polímeros/química , Animais , Sobrevivência Celular/efeitos dos fármacos , Feminino , Inativação Gênica , Glutationa/metabolismo , Humanos , Células MCF-7 , Camundongos
16.
Sci Rep ; 9(1): 6364, 2019 04 24.
Artigo em Inglês | MEDLINE | ID: mdl-31019222

RESUMO

In arid regions, higher irrigation quota for conventional farming causes substantial conflict between water supply and demand for crop production. Innovations in cropping systems are needed to alleviate this issue. A field experiment was conducted in northwestern China to assess whether straw and plastic managements in wheat/maize intercropping could alleviate these issues. Integrating no tillage with two-year plastic and straw mulching (NTMI2) improved grain yields by 13.8-17.1%, compared to conventional tillage without straw residue and annual new plastic mulching (CTI). The NTMI2 treatment reduced soil evaporation by 9.0-17.3% and the proportion of evaporation to evapotranspiration (E/ET) by 8.6-17.5%, compared to CTI. The NTMI2 treatment weakened wheat competition of soil moisture from maize strip during wheat growth period, and enhanced wheat compensation of soil moisture for maize growth after wheat harvest, compared with CTI. Thus, soil water movement potential of NTMI2 was lowest during wheat growth period, but it was highest during maize-independent growth stage after wheat harvest. The NTMI2 treatment increased evapotranspiration before maize silking, decreased from maize silking to early-filling stage, and increased after the early-filling stage of maize, this effectively coordinated water demand contradiction of intercrops at early and late stages. The NTMI2 treatment improved WUE by 12.4-17.2%, compared with CTI. The improved crop yields and WUE was attributed to the coordinated water competition and compensation, and the decreased soil evaporation and E/ET.


Assuntos
Agricultura/métodos , Triticum/crescimento & desenvolvimento , Água/metabolismo , Zea mays/crescimento & desenvolvimento , Irrigação Agrícola/instrumentação , Irrigação Agrícola/métodos , Agricultura/instrumentação , Biomassa , China , Secas/prevenção & controle , Plásticos , Solo/química , Triticum/metabolismo , Zea mays/metabolismo
17.
Colloids Surf B Biointerfaces ; 155: 497-506, 2017 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-28475986

RESUMO

High photoluminescence (PL) quantum yield (QY), photostability CdSe@ZnS/ZnS core/multishell quantum dots (CM-QDs) were first applied for bioimaging. The solubility, stability and biocompatible of the fluorescence imaging probes were constructed by self-assembly of CM-QDs and pH-responsive methoxy poly(ethylene glycol)-poly(ß-amino ester/amidoamine)-dodecylamine (mPEG-PAEA-DDA) multiblock copolymers. The resulting CM-QDs-loaded mPEG-PAEA-DDA micelles (CM-QDs-PEG-PAEA-DDA) exhibited lower cell cytotoxicity and higher fluorescence intensity than the core/shell CdSe@ZnS QDs-encapsulated mPEG-PAEA-DDA micelles (CS-QDs-PEG-PAEA-DDA). Moreover, the in vivo fluorescence imaging ability confirmed that the CM-QDs-PEG-PAEA-DDA can be employed as a pH-triggerable targeting imaging probe for detection of a rat bearing cerebral ischemia disease. Therefore, we believed that the CM-QDs-PEG-PAEA-DDA may be the next generation of fluorescence imaging probes for targeted diagnosis acidic pathological areas, using pH as a stimulus.


Assuntos
Isquemia Encefálica/diagnóstico por imagem , Micelas , Imagem Óptica/métodos , Polímeros/química , Pontos Quânticos/química , Acetatos/química , Animais , Cádmio/química , Sobrevivência Celular/efeitos dos fármacos , Células Hep G2 , Humanos , Concentração de Íons de Hidrogênio , Microscopia Eletrônica de Transmissão , Sondas Moleculares/química , Polímeros/farmacologia , Pontos Quânticos/ultraestrutura , Ratos , Compostos de Selênio/química , Compostos de Zinco/química
18.
Artigo em Inglês | MEDLINE | ID: mdl-21439867

RESUMO

Cobalt chrome alloy is a common material in prosthodontic restorations; however, instances of palmoplantar pustulosis owing to cobalt allergy are rare. Here, we report an unusual case of palmoplantar pustulosis in the hands and feet of a 58-year-old male patient caused by a cobalt allergy. The patient developed palmoplantar pustulosis characterized by redness, pustules, vesicles, and scaly erythema on his hands and feet 1 month after obtaining cobalt chromium alloy cast crowns on his molar teeth. The symptoms persisted for 1 year. He underwent standard patch testing, which showed a strong positive reaction to cobalt chloride. After the crowns were removed, the symptoms disappeared in 3 weeks. This study may serve to remind dental practitioners to be aware of potential allergic reactions to dental materials used in prosthodontic treatment and to enable them to recognize a metal allergy if it appears.


Assuntos
Cobalto/efeitos adversos , Coroas/efeitos adversos , Ligas Dentárias/efeitos adversos , Dermatite Alérgica de Contato/etiologia , Psoríase/etiologia , Restauração Dentária Permanente/efeitos adversos , Dermatite Alérgica de Contato/patologia , Remoção de Dispositivo , Humanos , Hipersensibilidade/etiologia , Hipersensibilidade/patologia , Ativação Linfocitária , Masculino , Pessoa de Meia-Idade , Testes do Emplastro , Psoríase/patologia
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