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1.
Int J Mol Sci ; 25(5)2024 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-38474272

RESUMEN

Cellulose crystallinity is a crucial factor influencing stem strength and, consequently, wheat lodging. However, the genetic dissection of cellulose crystallinity is less reported due to the difficulty of its measurement. In this study, VIS/NIR spectra and cellulose crystallinity were measured for a wheat accession panel with diverse genetic backgrounds. We developed a reliable VIS/NIR model for cellulose crystallinity with a high determination coefficient (R2) (0.95) and residual prediction deviation (RPD) (4.04), enabling the rapid screening of wheat samples. A GWAS of the cellulose crystallinity in 326 wheat accessions revealed 14 significant SNPs and 13 QTLs. Two candidate genes, TraesCS4B03G0029800 and TraesCS5B03G1085500, were identified. In summary, this study establishes an efficient method for the measurement of cellulose crystallinity in wheat stems and provides a genetic basis for enhancing lodging resistance in wheat.


Asunto(s)
Celulosa , Estudio de Asociación del Genoma Completo , Triticum/genética , Sitios de Carácter Cuantitativo , Polimorfismo de Nucleótido Simple
2.
J Environ Manage ; 325(Pt B): 116694, 2023 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-36343400

RESUMEN

Poor management of crop residues leads to environmental pollution and composting is a sustainable practice for addressing the challenge. However, knowledge about composting with pure crop straw is still limited, which is a novel and feasible composting strategy. In this study, pure corn straw was in-situ composted for better management. Community structure of ß-glucosidase-producing microorganisms during composting was deciphered using high-throughput sequencing. Results showed that the compost was mature with organic matter content of 37.83% and pH value of 7.36 and pure corn straw could be composted successfully. Cooling phase was major period for cellulose degradation with the highest ß-glucosidase activity (476.25 µmol·p-Nitr/kg·dw·min) and microbial diversity (Shannon index, 3.63; Chao1 index, 500.81). Significant compositional succession was observed in the functional communities during composting with Streptomyces (14.32%), Trichoderma (13.85%) and Agromyces (11.68%) as dominant genera. ß-Glucosidase-producing bacteria and fungi worked synergistically as a network to degrade cellulose with Streptomyces (0.3045**) as the key community revealed by multi-interaction analysis. Organic matter (-0.415***) and temperature (-0.327***) were key environmental parameters regulating cellulose degradation via influencing ß-glucosidase-producing communities, and ß-glucosidase played a key role in mediating this process. The above results indicated that responses of ß-glucosidase-producing microorganisms to cellulose degradation were reflected at both network and individual levels and multi-interaction analysis could better explain the relationship between variables concerning composting cellulose degradation. The work is of significance for understanding cellulose degradation microbial communities and process during composting of pure corn straw.


Asunto(s)
Compostaje , Streptomyces , Trichoderma , beta-Glucosidasa/metabolismo , Zea mays/metabolismo , Suelo , Celulosa/metabolismo , Trichoderma/metabolismo , Streptomyces/metabolismo , Estiércol
3.
Langmuir ; 29(3): 927-31, 2013 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-23234580

RESUMEN

Spherical Au-Pt alloy nanoparticles of 10 nm average size have been prepared on a H-terminated Si(100) substrate by an extremely simple method of dip-coating. X-ray photoelectron spectroscopy and glancing-incidence X-ray diffraction confirm the formation of Au-Pt alloy. The Au(3+) ions are first reduced on the Si substrate upon dipping, and the freshly formed Au nuclei then work as a "catalyst" by promoting the reduction of PtCl(6)(2-) ions on the Au nuclei. The subsequent interdiffusion of Au and Pt atoms leads to the observed alloy formation. The present method provides an environment-friendly, low-cost route to preparing anode electrodes in fuel cells.


Asunto(s)
Aleaciones/química , Oro/química , Nanopartículas del Metal/química , Platino (Metal)/química , Silicio/química , Temperatura , Electrodos , Tamaño de la Partícula , Propiedades de Superficie
4.
Langmuir ; 28(14): 6114-23, 2012 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-22448630

RESUMEN

The steady-state shear and linear viscoelastic deformations of semidilute suspensions of rod-shaped nanocrystalline cellulose (NCC) particles in 1.0% hydroxyethyl cellulose and carboxymethyl cellulose solutions were investigated. Addition of NCC at the onset of semidilute suspension concentration significantly altered the rheological and linear viscoelastic properties of semidilute polymer solutions. The low-shear viscosity values of polymers solutions were increased 20-490 times (depending on polymer molecular weight and functional groups) by the presence of NCC. NCC suspensions in polymer solutions exhibited yield stresses up to 7.12 Pa. Viscoelasticity measurements also showed that NCC suspended polymer solutions had higher linear elastic moduli than the loss moduli. All of those results revealed the gel formation of NCC particles and presence of internal structures. The formation of a weak gel structure was due to the nonadsorbing macromolecules which caused the depletion-induced interaction among NCC particles. A simple interaction energy model was used to show successfully the flocculation of NCC particles in the presence of nonadsorbing polymers. The model is based on the incorporation of the depletion interaction term between two parallel plates into the DLVO theory for cubic prismatic rod shaped NCC particles.


Asunto(s)
Carboximetilcelulosa de Sodio/química , Celulosa/análogos & derivados , Nanopartículas/química , Agua/química , Celulosa/química , Coloides , Elasticidad , Soluciones , Viscosidad
5.
J Liposome Res ; 22(2): 100-9, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22007962

RESUMEN

The aims of this study were to design the formulation of curcumin (CUR) liposomes coated with N-trimethyl chitosan chloride (TMC) and to evaluate in vitro release characteristics and in vivo pharmacokinetics and bioavailability of TMC-coated CUR liposomes in rats. The structure of synthesized TMC was examined by infrared spectroscopy, with the presence of trimethyl groups, and by proton nuclear magnetic resonance spectroscopy, indicating the high degree of substitution quaternization (65.6%). Liposomes, composed of soybean phosphotidylcholine, cholestrol, and D-α-tocopheryl polyethylene glycol 1000 succinate, were prepared by a thin-film dispersion method. Characteristics of the CUR liposomes, including entrapment efficiency (86.67%), drug-loading efficiency (2.33%), morphology, particle size (221.4 nm for uncoated liposomes and 657.7 nm for TMC-coated liposomes), and zeta potential (-9.63 mV for uncoated liposomes and +15.64 mV for TMC-coated liposomes) were investigated. Uncoated CUR liposomes and TMC-coated CUR liposomes showed a similar in vitro release profile. Nearly 50% of CUR was released from liposomes, whereas 80% of CUR was released from CUR propylene glycol solution. CUR incorporated into TMC-coated liposomes exhibited different pharmacokinetic parameters and enhanced bioavailability (C(max) = 46.13 µg/L, t(1/2) = 12.05 hours, AUC = 416.58 µg/L·h), compared with CUR encapsulated by uncoated liposomes (C(max) = 32.12 µg/L, t(1/2) = 9.79 hours, AUC = 263.77 µg/L·h) and CUR suspension (C(max) = 35.46 µg/L, t(1/2) = 3.85 hours, AUC = 244.77 µg/L·h). In conclusion, oral delivery of coated CUR liposomes is a promising strategy for poorly water-soluble CUR.


Asunto(s)
Quitosano/química , Curcumina/administración & dosificación , Curcumina/farmacocinética , Portadores de Fármacos/química , Liposomas/química , Administración Oral , Animales , Disponibilidad Biológica , Quitosano/administración & dosificación , Quitosano/farmacocinética , Curcumina/química , Portadores de Fármacos/administración & dosificación , Portadores de Fármacos/farmacocinética , Liposomas/administración & dosificación , Liposomas/farmacocinética , Estructura Molecular , Ratas
6.
Spectrochim Acta A Mol Biomol Spectrosc ; 266: 120419, 2022 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-34619506

RESUMEN

Nitroaromatic compounds (NACs) can lead to various environmental pollution healh problems. In order to effectively recognize and sense NACs, a novel coordination polymers (CPs) with fluorescent characteristic [Zn3(btc)2(tpt)(H2O)2]·4H2O (1) (tpt = tris(4-pyridyl)triazine, H3btc = 1,3,5-benzenetricarboxylic acid) has been triumphantly prepared as an fluorescence probe by solvothermal method. 1 possesses remarkable PH stability ranging from 2.0 to 12.0 and is also stable in different pure organic solvents. It should be noted that 1 manifests a fluorescence quenching response against the detection of selectivity and sensitivity towards 2,4,6-trinitrophenol (TNP) in aqueous solution. It also makes analysis on the limit of detection towards TNP, which is as low as 0.94 µM compared with most reported CPs sensors for TNP. Therefore, 1 can become a satisfactory sensor for TNP detection with remarkable selectivity, strong anti-interference and favorable recyclability. In addition, the quenching mechanisms were also discussed. It was supposed that the mechanisms of photoinduced electron transfer (PET) as well as resonance energy transfer (RET) might be the main influencing factors.


Asunto(s)
Luminiscencia , Polímeros , Picratos , Zinc
7.
J Drug Target ; 25(6): 471-484, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28135859

RESUMEN

This review focuses on recent investigations that used Pluronic P123 (P123) as pharmaceutical ingredients in vesicle, micelle, mixed micelle, in situ gel, tablet and emulsion. The main results from these studies show that P123 can significantly increase the stability of incorporated hydrophobic drugs with enhanced in vitro cytotoxicity and cellular uptake of anticancer drugs. Moreover, modified forms of P123 with RGD, folate or other targeted marker have shown its therapeutic potentials in various types of tumors and cancers. Furthermore, modified forms of P123 alone and/or mixed with other copolymers have less toxic effects and more tumor-specific delivery of anticancer drugs. They are promising materials as a nanoplatform for the drug delivery. Finally, the future perspectives of the field are briefly discussed.


Asunto(s)
Antineoplásicos/administración & dosificación , Sistemas de Liberación de Medicamentos , Poloxaleno/administración & dosificación , Animales , Antineoplásicos/efectos adversos , Antineoplásicos/farmacología , Portadores de Fármacos/química , Estabilidad de Medicamentos , Humanos , Interacciones Hidrofóbicas e Hidrofílicas , Oligopéptidos/administración & dosificación , Poloxaleno/efectos adversos , Poloxaleno/química
8.
Carbohydr Polym ; 152: 487-495, 2016 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-27516296

RESUMEN

High solids content polyurethane (PU) nanocomposites with enhanced thermal and mechanical properties were produced by incorporating of low fractions of cellulose nanocrystals (CNC) in a solvent-free process. This involved the use of a simple procedure to produce well dispersed and stable suspensions of CNC in biobased polyols, which were then used to produce PU-CNC nanocomposites. Transmission electron microscopy revealed that individual CNC particles were dispersed homogenously within the PU matrix. FTIR results suggested that CNC particles are covalently bonded to the PU molecular chains during polymerization. The thermal mechanical properties of the nanocomposites are significantly improved over pure PU as indicated by differential scanning calorimetry and dynamic mechanical analysis. Compared to pure PU, the PU nanocomposites made with the addition of only 0.5% of CNC had glass transition temperatures that were 6°C higher, their Young's moduli were about 10% higher and their abrasion resistance was higher by about 25%. The optimal composition contains only 0.5% CNC (w/w) which indicates that there is good potential for utilization of low levels of CNC for reinforcement of PU composites made using biobased polyols.


Asunto(s)
Celulosa/química , Nanocompuestos/química , Nanopartículas/química , Polímeros/química , Poliuretanos/química
9.
Carbohydr Polym ; 152: 214-221, 2016 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-27516267

RESUMEN

Edible films of Flammulina velutipes polysaccharide were prepared and characterized in terms of rheological, optical, morphologic, mechanical and barrier properties to evaluate their potential application in food packaging. Results suggested that FVP film prepared by the solution of 1:150 (w/v) had the optimal mechanical property, smooth and uniform surface, and good barrier property to water (37.92±2.00gmm/m(2)hkPa) and oxygen (37.92±2.01meq/kg). The capacity of film-formation might be related to inter-molecular and intra-molecular hydrogen bonds of FVP and formation of ß-glycosidic bonds during the process of film-formation. These findings will contribute to a theoretical basis for the development of FVP film in food packaging.


Asunto(s)
Carbohidratos de la Dieta/síntesis química , Flammulina/química , Embalaje de Alimentos , Membranas Artificiales , Polisacáridos/química , Aditivos Alimentarios/síntesis química , Aditivos Alimentarios/química , Embalaje de Alimentos/métodos , Permeabilidad , Polisacáridos/síntesis química , Reología , Resistencia a la Tracción , Agua/química
10.
J Biomed Nanotechnol ; 11(3): 436-46, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26307827

RESUMEN

Curcumin (Cur), a hydrophobic polyphenolic compound, possesses a wide range of biological activities. However, its prominent application in cancer treatment is limited due to low aqueous solubility and rapid metabolism. Recently, micelle-based drug delivery system has been proven to be an attractive alternative for poorly soluble drugs. In order to improve the application of Cur as an anti-cancer agent, in this study, we synthesized the αvß3 integrin-targeted peptide (RGD) functionalized polymer (RGD-PEG-PLA). The RGD conjugated Cur loaded micelles (Cur-RPP) were prepared using the thin-film hydration method with modification and the preparation process was optimized with a central composite design. The obtained Cur-RPP presented spherical shape with a particle size of 20 nm and high drug loading (4.70%). Compared with the Cur propylene glycol solution, the in vitro release of Cur from the prepared micelles showed the sustained-release property. Cellular uptake of Cur-RPP was found to be higher than that of non-RGD modified micelles due to the binding effect between αvß3 integrin and RGD in human umbilical vein endothelial cells (HUVEC) and mouse melanoma cell lines (B16). In B16 tumor-bearing mice, Cur-RPP showed the stronger inhibiting effect on growth of tumor compared with non-RGD modified micelles. It could be concluded from these results that the RGD modified micelles might be a potential carrier for Cur.


Asunto(s)
Curcumina/administración & dosificación , Nanocápsulas/administración & dosificación , Neoplasias Experimentales/tratamiento farmacológico , Neoplasias Experimentales/metabolismo , Oligopéptidos/farmacocinética , Polietilenglicoles/química , Animales , Antineoplásicos/administración & dosificación , Antineoplásicos/química , Supervivencia Celular/efectos de los fármacos , Difusión , Masculino , Ratones , Micelas , Nanocápsulas/química , Nanocompuestos/química , Nanocompuestos/ultraestructura , Neoplasias Experimentales/patología , Oligopéptidos/química , Resultado del Tratamiento
11.
J Biomed Nanotechnol ; 11(5): 865-76, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-26349398

RESUMEN

The purpose of this study was to formulate nanoparticles with an elaborate structure for oral delivery of exendin-4 using a simple preparation process. The nanoparticles possessed a mixed lipid shell and an aqueous core which contained drug-loaded micelles. Formulation was optimized by a central composite design and the structure of the nanoparticles was validated. The efficacy for delivery of exendin-4 was evaluated both in vitro and in vivo. The drug encapsulation efficiency of the nanoparticles reached 97.7%. The nanoparticles greatly enhanced the cellular uptake and transport of encapsulated exendin-4 in vitro. The in situ study showed that exendin-4 could be transported across the epithelium into intestinal capillaries, while the lipid materials largely remained in the epithelium. Pharmacodynamic studies in diabetic KKAy mice demonstrated that the exendin-4-loaded nanoparticles exhibited a marked hypoglycemia effect with a pharmacological availability of 12.7% after intestinal administration.


Asunto(s)
Hipoglucemiantes , Absorción Intestinal , Nanopartículas , Péptidos/administración & dosificación , Péptidos/farmacocinética , Ponzoñas/administración & dosificación , Ponzoñas/farmacocinética , Animales , Células CACO-2 , Diabetes Mellitus Experimental/tratamiento farmacológico , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/patología , Portadores de Fármacos/química , Exenatida , Humanos , Hipoglucemiantes/administración & dosificación , Hipoglucemiantes/farmacocinética , Absorción Intestinal/efectos de los fármacos , Liposomas/química , Masculino , Ratones , Ratones Obesos , Ratones Transgénicos , Micelas , Nanopartículas/metabolismo , Ratas , Ratas Sprague-Dawley , Agua/química
12.
ACS Appl Mater Interfaces ; 4(11): 5945-8, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23039103

RESUMEN

Self-assembly of thiol-modified oligonucleotides on Au films has great importance for biosensor applications. Prior to the self-assembly, a piranha treatment (PT) is commonly used to clean the Au surface. Here we report that near-surface oxidized sulfur modifications on Au thin films by PT for longer than 60 s have serious effects on the self-assembled monolayer (SAM) formation of thiol-modified single-stranded thrombin binding aptamer (s-TBA), and a PT time of 10-30 s is optimal for s-TBA SAM formation. These results have important implication to SAM formation of biomolecules, especially for the thiol-modified ones where a careful consideration of this key step could significantly enhance the SAM formation and biosensor performance.


Asunto(s)
Técnicas Biosensibles/métodos , Oro/química , Membranas Artificiales , Compuestos de Sulfhidrilo/análisis , Compuestos de Sulfhidrilo/química , Azufre/química , Calor , Ensayo de Materiales , Oxidación-Reducción , Propiedades de Superficie
13.
Colloids Surf B Biointerfaces ; 97: 101-8, 2012 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-22609589

RESUMEN

In this study, curcumin (Cur) loaded mixed micelles (Cur-PF), composed of Pluronic P123 (P123) and Pluronic F68 (F68), was prepared using the thin-film hydration method and evaluated in vitro. The preparation process was optimized with a central composite design (CCD). The average size of the mixed micelles was 68.2 nm, and the encapsulating efficiency for Cur was 86.93%, and 6.996% for drug-loading. Compared with the Cur propylene glycol solution, the in vitro release of Cur from Cur-PF presented the sustained-release property. The in vitro cytotoxicity assay showed that the IC(50) values on MCF-7 cells for Cur-PF and free Cur in DMSO solution were 5.04 µg/mL and 8.35 µg/mL, while 2.52 µg/mL and 8.27 µg/mL on MCF-7/ADR cells. It could be concluded from the results that P123/F68 mixed micelles might serve as a potential nanocarrier to improve the solubility and biological activity of Cur.


Asunto(s)
Curcumina/química , Curcumina/farmacología , Micelas , Poloxaleno/química , Poloxámero/química , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Humanos
14.
J Biomed Nanotechnol ; 7(3): 358-65, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21830476

RESUMEN

The objective of this study was to develop a polymeric delivery system to improve the solubility and biological activity of Quercetin (QT). QT loaded mixed micelles, composed of Pluronic P123 (P123) and D-a-tocopheryl polyethylene glycol succinate (TPGS) with proportion of 7:3 (QT-P/T), were prepared by thin-film hydration method. The average size of the mixed micelles was 18.43 nm, and the encapsulating efficiency for QT was 88.94 +/- 3.71%, drug-loading was 10.59 +/- 0.38%. The solubility of QT in QT-P/T was 5.56 mg/mL, which was about 2738-fold that of crude QT in water. Compared with the QT propylene glycol solution, the in vitro release of QT from QT-P/T presented the sustained-release property. The in vitro cytotoxicity assay showed that the IC50 values on MCF-7 cells for QT-P/T and QT loaded P123 micelles (QT-P123) were 7.13 microg/mL and 10.73 microg/mL, respectively, while 7.23 microg/mL and 14.47 microg/mL on MCF-7/ADR cells. From the results, it can be concluded that, P123/TPGS mixed micelles may serve as a pharmaceutical nano carrier with improved solubility and biological activity for QT.


Asunto(s)
Antineoplásicos/farmacología , Micelas , Poloxaleno , Polietilenos , Quercetina/farmacología , Succinatos , Tocoferoles/farmacología , Neoplasias de la Mama/tratamiento farmacológico , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Química Farmacéutica , Sistemas de Liberación de Medicamentos , Femenino , Humanos , Concentración 50 Inhibidora , Microscopía Electrónica de Transmisión , Estructura Molecular , Tamaño de la Partícula , Poloxaleno/química , Polietilenos/química , Succinatos/química
15.
Neurosci Lett ; 485(1): 16-20, 2010 Nov 12.
Artículo en Inglés | MEDLINE | ID: mdl-20732384

RESUMEN

Stress exposure in addicted individuals is known to provoke drug craving, presumably through a memory-like process, but less is known about the effects of stress on non-drug-related affective memory retrieval per se in such individuals, which is likely to provide important insights into therapy for relapse. In present study, we explored the effect of stress on retrieval of neutral and emotionally valenced (positive and negative) words in abstinent heroin addicts. In present study, 28 male inpatient abstinent heroin addicts and 20 sex-, age-, education- and economic status-matched healthy control participants were assessed for 24h delayed recall of valenced and neutral word lists on two occasions 4 weeks apart-once in a nonstress control condition, once after exposure to the Trier Social Stress Test in a counterbalanced design. In addition, attention, working memory, blood pressure, heart rate and salivary cortisol were assessed. We found acute stress at the time of word list recall enhanced retrieval of positively valenced words, but no effect on negative and neutral word retrieval in abstinent heroin addicts was observed. No changes were detected for attention and working memory. The stressor induced a significant increase in salivary free cortisol, blood pressure and heart rate. Stress can enhance non-drug-related positive memory in abstinent heroin addicts. Our findings will provide richer information in understanding dysregulation of their emotional memory processing under stress and hopefully provide insight into designing improved treatments for drug addiction.


Asunto(s)
Dependencia de Heroína/psicología , Recuerdo Mental , Estrés Psicológico/psicología , Adulto , Atención , Presión Sanguínea , Estudios de Casos y Controles , Frecuencia Cardíaca , Dependencia de Heroína/complicaciones , Dependencia de Heroína/fisiopatología , Humanos , Hidrocortisona/análisis , Masculino , Memoria a Corto Plazo , Saliva/química , Semántica , Estrés Psicológico/complicaciones , Estrés Psicológico/fisiopatología , Adulto Joven
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