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1.
Cereb Cortex ; 34(6)2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38836835

RESUMEN

Neocortex is a complex structure with different cortical sublayers and regions. However, the precise positioning of cortical regions can be challenging due to the absence of distinct landmarks without special preparation. To address this challenge, we developed a cytoarchitectonic landmark identification pipeline. The fluorescence micro-optical sectioning tomography method was employed to image the whole mouse brain stained by general fluorescent nucleotide dye. A fast 3D convolution network was subsequently utilized to segment neuronal somas in entire neocortex. By approach, the cortical cytoarchitectonic profile and the neuronal morphology were analyzed in 3D, eliminating the influence of section angle. And the distribution maps were generated that visualized the number of neurons across diverse morphological types, revealing the cytoarchitectonic landscape which characterizes the landmarks of cortical regions, especially the typical signal pattern of barrel cortex. Furthermore, the cortical regions of various ages were aligned using the generated cytoarchitectonic landmarks suggesting the structural changes of barrel cortex during the aging process. Moreover, we observed the spatiotemporally gradient distributions of spindly neurons, concentrated in the deep layer of primary visual area, with their proportion decreased over time. These findings could improve structural understanding of neocortex, paving the way for further exploration with this method.


Asunto(s)
Aprendizaje Profundo , Neocórtex , Neuronas , Animales , Neocórtex/citología , Ratones , Ratones Endogámicos C57BL , Masculino , Imagenología Tridimensional/métodos , Tomografía Óptica/métodos
2.
Soft Matter ; 20(6): 1173-1185, 2024 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-38164656

RESUMEN

Glycyrrhizic acid (GA), a naturally derived food-grade saponin molecule, is a promising alternative to synthetic surfactants for stabilizing multiphase systems including emulsions and foams, due to its biological activity and surface-active properties. Understanding the interfacial behavior of GA, particularly in relation to its complex self-assembly behaviors in water induced by multiple environmental stimuli, is crucial to its application in multiphase systems. In this study, we comprehensively investigate the interfacial structure and rheological properties of GA systems, as a function of pH and temperature, through Langmuir-Blodgett films combined with atomic force microscopy, interfacial particle tracking, adsorption kinetics, stress-relaxation behavior and interfacial dilatational rheology. The variation of solution pH provokes pronounced changes in the interfacial properties of GA. At pH 2 and 4, GA fibril aggregates/fibrils adsorb rapidly, followed by rearrangement into large lamellar and rod-like structures, forming a loose and heterogeneous fibrous network at the interface, which exhibit a stretchable gel-like behavior. In contrast, GA at pH 6 and 8, featuring micelles or monomers in solutions, adsorb slowly to the interface and re-assemble partially into small micelle-like or irregular structures, which lead to a dense and homogeneous interfacial layer with stiffer glassy-like responses. With successively elevated temperature, the GA structures (pH 4) at the interface break into smaller fragments and further adsorption is promoted. Upon cooling, the interfacial tension of GA further decreases and a highly elastic interfacial layer may be formed. The diverse GA assemblies in bulk solution impart them with rich and intriguing interfacial behaviors, which may provide valuable mechanistic insights for the development of novel edible soft matter stabilized by GA.


Asunto(s)
Ácido Glicirrínico , Agua , Tensión Superficial , Propiedades de Superficie , Reología , Emulsiones , Agua/química , Adsorción
3.
Opt Express ; 31(3): 4537-4552, 2023 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-36785419

RESUMEN

In traditional fluorescence microscopy, it is hard to achieve a large uniform imaging field with high resolution. In this manuscript, we developed a confocal fluorescence microscope combining the microlens array with spatial light modulator to address this issue. In our system, a multi-spot array generated by a spatial light modulator passes through the microlens array to form an optical probe array. Then multi-spot adaptive pixel-reassignment method for image scanning microscopy (MAPR-ISM) will be introduced in this parallelized imaging to improve spatial resolution. To generate a uniform image, we employ an optimized double weighted Gerchberg-Saxton algorithm (ODWGS) using signal feedback from the camera. We have built a prototype system with a FOV of 3.5 mm × 3.5 mm illuminated by 2500 confocal points. The system provides a lateral resolution of ∼0.82 µm with ∼1.6 times resolution enhancement after ISM processing. And the nonuniformity across the whole imaging field is 3%. Experimental results of fluorescent beads, mouse brain slices and melanoma slices are presented to validate the applicability and effectiveness of our system.

4.
Opt Lett ; 48(4): 940-943, 2023 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-36790980

RESUMEN

Fluorescence microscopy typically suffers from aberration induced by system and sample, which could be circumvented by image deconvolution. We proposed a novel, to the best of our knowledge, Richardson-Lucy (RL) model-driven deconvolution framework to improve reconstruction performance and speed. Two kinds of neural networks within this framework were devised, which are partially interpretable compared with previous deep learning methods. We first introduce RL into deep feature space, which has superior generalizability to the convolutional neural networks (CNN). We further accelerate it with an unmatched backprojector, providing a five times faster reconstruction speed than classic RL. Our deconvolution approaches outperform both CNN and traditional methods regarding image quality for blurred images caused by out-of-focus or imaging system aberration.

5.
Int J Mol Sci ; 24(16)2023 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-37628974

RESUMEN

Compared to young people and adults, there are differences in the ability of elderly people to resist diseases or injuries, with some noticeable features being gender-dependent. However, gender differences in age-related viscera alterations are not clear. To evaluate a potential possibility of gender differences during the natural aging process, we used three age groups to investigate the impact on spleens, kidneys, and adrenal glands. The immunofluorescence results showed that male-specific p21 proteins were concentrated in the renal tubule epithelial cells of the kidney. Histological staining revealed an increase in the frequencies of fat vacuoles located in the renal tubule epithelial cells of the cortex, under the renal capsule in the kidneys of male mice with age. In female mice, we found that the width of the globular zone in the adrenal gland cortex was unchanged with age. On the contrary, the male displayed a reduction in width. Compared to females, the content of epinephrine in adrenal gland tissue according to ELISA analysis was higher in adults, and a greater decline was observed in aged males particularly. These data confirmed the age-dependent differences between female and male mice; therefore, gender should be considered one of the major factors for personalized treatment in clinical diagnosis and treatment.


Asunto(s)
Corteza Suprarrenal , Glándulas Suprarrenales , Femenino , Masculino , Animales , Ratones , Riñón , Corteza Cerebral , Envejecimiento
6.
Opt Express ; 30(4): 5177-5191, 2022 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-35209487

RESUMEN

Fluorescence microscopy plays an irreplaceable role in biomedicine. However, limited depth of field (DoF) of fluorescence microscopy is always an obstacle of image quality, especially when the sample is with an uneven surface or distributed in different depths. In this manuscript, we combine deep learning with Fresnel incoherent correlation holography to describe a method to obtain significant large DoF fluorescence microscopy. Firstly, the hologram is restored by the Auto-ASP method from out-of-focus to in-focus in double-spherical wave Fresnel incoherent correlation holography. Then, we use a generative adversarial network to eliminate the artifacts introduced by Auto-ASP and output the high-quality image as a result. We use fluorescent beads, USAF target and mouse brain as samples to demonstrate the large DoF of more than 400µm, which is 13 times better than that of traditional wide-field microscopy. Moreover, our method is with a simple structure, which can be easily combined with many existing fluorescence microscopic imaging technology.

7.
Molecules ; 27(19)2022 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-36235079

RESUMEN

Responsive dual-structured emulsions and gel emulsions have attracted more and more attention due to their complex microstructures, on-demand responsive properties, and controlled release of active cargoes. In this work, the effect of monoglyceride (MG)-based oil phase structuring on the formation and stability, structural properties, and thermoresponsive and cargo release behavior of gel emulsions stabilized by glycyrrhizic acid (GA) nanofibrils were investigated. Owing to the formation of GA fibrillar networks in the aqueous phase and MG crystalline networks in the oil phase, a stable dual-structured gel emulsion can be successfully developed. The microstructure of the dual-structured gel emulsions largely depended on the concentration of MG in the oil phase. At low MG concentrations (1-2 wt%), the larger formed and lamellar MG crystals may pierce the interfacial fibrillar film, inducing the formation of partially coalesced droplets. In contrast, at high MG concentrations (4 wt% or above), the smaller MG crystals with enhanced interfacial activity can lead to the formation of a bilayer shell of GA nanofibrils and MG crystals, thus efficiently inhibiting the interfacial film damage and forming a jamming structure with homogeneously distributed small droplets. Compared to pure GA nanofibril gel emulsions, the GA-MG dual-structured gel emulsions showed significantly improved mechanical performance as well as good thermoresponsive behavior. Moreover, these stable GA-MG gel emulsions can be used as food-grade delivery vehicles for encapsulating and protecting hydrophobic and hydrophilic bioactive cargoes. They also have great potential as novel and efficient aroma delivery systems showing highly controlled volatile release. The dual-structured emulsion strategy is expected to broaden the applications of natural saponin GA-based gel emulsions in the food, pharmaceutical, and personal care industries.


Asunto(s)
Ácido Glicirrínico , Saponinas , Preparaciones de Acción Retardada , Emulsiones/química , Glicéridos , Ácido Glicirrínico/química , Monoglicéridos , Saponinas/química , Agua/química
8.
Brain Behav Immun ; 91: 568-577, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33197546

RESUMEN

The reactivity of microglia within the spinal cord in response to nerve injury, has been associated with the development and maintenance of neuropathic pain. However, the temporal changes in microglial reactivity following nerve injury remains to be defined. Importantly, the magnitude of behavioural allodynia displayed and the relationship to the phenotypic microglial changes is also unexplored. Using a heterozygous CX3CR1gfp+ transgenic mouse strain, we monitored microglial activity as measured by cell density, morphology, process movement and process length over 14 days following chronic constriction of the sciatic nerve via in vivo confocal microscopy. Uniquely this relationship was explored in groups of male mice which had graded nerve injury and associated graded behavioural mechanical nociceptive sensitivity. Significant mechanical allodynia was quantified from the ipsilateral hind paw and this interacted with the extent of nerve injury from day 5 to day 14 (p < 0.009). The extent of this ipsilateral allodynia was proportional to the nerve injury from day 5 to 14 (Spearman rho = -0.58 to -0.77; p < 0.002). This approach allowed for the assessment of the association of spinal microglial changes with the magnitude of the mechanical sensitivity quantified behaviourally. Additionally, the haemodynamic response in the somatosensory cortex was quantified as a surrogate measure of neuronal activity. We found that spinal dorsal horn microglia underwent changes unilateral to the injury in density (Spearman rho = 0.47; p = 0.01), velocity (Spearman rho = -0.68; p = 0.00009), and circularity (Spearman rho = 0.55; p = 0.01) proportional to the degree of the neuronal injury. Importantly, these data demonstrate for the first time that the mechanical allodynia behaviour is not a binary all or nothing state, and that microglial reactivity change proportional to this behavioural measurement. Increased total haemoglobin levels in the somatosensory cortex of higher-grade injured animals was observed when compared to sham controls suggesting increased neuronal activity in this brain region. The degree of phenotypic microglial changes quantified here, may explain how microglia can induce both rapid onset and sustained functional changes in the spinal cord dorsal horn, following peripheral injury.


Asunto(s)
Neuralgia , Traumatismos de los Nervios Periféricos , Animales , Hiperalgesia , Masculino , Ratones , Microglía , Traumatismos de los Nervios Periféricos/complicaciones , Ratas , Ratas Sprague-Dawley , Médula Espinal
9.
J Nanobiotechnology ; 19(1): 224, 2021 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-34320999

RESUMEN

Systemic chemotherapy is still the primary treatment for advanced-stage nasopharyngeal carcinoma (NPC), but only limited therapeutic success has been achieved in the past decade because of drug resistance and systemic toxicity. Curcumin (Cur) is an effective alternative to chemotherapeutics because it showed remarkable therapeutic potential in the treatment of NPC. However, lack of tissue specificity and poor penetration in solid tumors are the major obstacles to effective therapy. Therefore, in this work, a self-assembled sub-30 nm therapeutic lipid nanoparticle loaded with Cur, named as Cur@α-NTP-LN, was constructed, specifically targeting scavenger receptor class B member 1 (SR-B1) and enhancing its therapeutic effects on NPC in vivo. Our results showed that Cur@α-NTP-LNs were effective and superior to free Cur on NPC cell-specific targeting, suppressing cell proliferation and inducing cell apoptosis. In vivo and ex vivo optical imaging revealed that Cur@α-NTP-LNs exerted high targeting efficiency, specifically accumulating in NPC xenograft tumors and delivering Cur into the tumor center after systemic administration. Furthermore, Cur@α-NTP-LNs exhibited a remarkable inhibitory effect on the growth of NPC subcutaneous tumors, with over 71 and 47% inhibition compared to Cur- and α-NTP-LNs-treated groups, respectively. In addition, Cur@α-NTP-LNs almost blocked NPC metastasis in a lung metastasis model of NPC and significantly improved the survival rate. Thus, the sub-30 nm Cur@α-NTP-LNs enhanced the solubility of Cur and demonstrated the ability of targeted Cur delivery into the center of the solid NPC tumor, performing synergistic inhibitory effects on the growth of NPC tumor and its metastasis with high efficiency.


Asunto(s)
Curcumina/farmacología , Portadores de Fármacos/farmacología , Sistemas de Liberación de Medicamentos/métodos , Liposomas/farmacología , Carcinoma Nasofaríngeo/tratamiento farmacológico , Neoplasias Nasofaríngeas/tratamiento farmacológico , Administración Cutánea , Animales , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Humanos , Neoplasias Pulmonares , Ratones , Nanopartículas , Metástasis de la Neoplasia , Tamaño de la Partícula , Péptidos , Solubilidad
10.
J Sep Sci ; 44(23): 4255-4263, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34648229

RESUMEN

Levetiracetam is an antiepileptic drug that is primarily approved by the Food and Drug Administration for the treatment of focal and generalized seizures. This study describes the development and validation of a highly selective and sensitive liquid chromatography-tandem mass spectrometry method with triple-stage fragmentation to determine levetiracetam in epileptic patient serum. After simple protein precipitation, the analytes were separated on a short reversed-phase column (Agilent Poroshell 120 SB-C18 column, 4.6 × 50 mm, 2.7 µm) using isocratic elution with 25% 0.1% formic acid in water (solvent A) and 75% methanol (solvent B) at a flow rate of 0.8 ml/min. The linear range is 0.5-50 µg/mL (R2  > 0.99). All the validation data, such as lower limit of quantification, linearity, specificity, recoveries, matrix effects, and other parameters, fit the request of biological method validation guidance. Passing-Bablok regression coefficients demonstrated that there is no constant bias and no proportional bias between the liquid chromatography-tandem mass spectrometry methods with triple-stage fragmentation and liquid multiple reaction monitoring. Bland-Altman plot showed that the developed liquid chromatography-tandem mass spectrometry method with triple-stage fragmentation method is reliable and accurate to determine levetiracetam in human serum.


Asunto(s)
Anticonvulsivantes/sangre , Levetiracetam/sangre , Cromatografía Líquida de Alta Presión , Monitoreo de Drogas , Humanos , Espectrometría de Masas en Tándem
11.
Molecules ; 26(19)2021 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-34641618

RESUMEN

The naturally occurring saponins exhibit remarkable interfacial activity and also possess many biological activities linking to human health benefits, which make them particularly attractive as bifunctional building blocks for formulation of colloidal multiphase food systems. This review focuses on two commonly used food-grade saponins, Quillaja saponins (QS) and glycyrrhizic acid (GA), with the aim of clarifying the relationship between the structural features of saponin molecules and their subsequent self-assembly and interfacial properties. The recent applications of these two saponins in various colloidal multiphase systems, including liquid emulsions, gel emulsions, aqueous foams and complex emulsion foams, are then discussed. A particular emphasis is on the unique use of GA and GA nanofibrils as sole stabilizers for fabricating various multiphase food systems with many advanced qualities including simplicity, ultrastability, stimulability, structural viscoelasticity and processability. These natural saponin and saponin-based colloids are expected to be used as sustainable, plant-based ingredients for designing future foods, cosmetics and pharmaceuticals.


Asunto(s)
Ácido Glicirrínico/química , Plantas/química , Saponinas de Quillaja/química , Coloides/química , Cosméticos/química , Tecnología de Alimentos , Estructura Molecular , Fitoquímicos/química
12.
J Food Sci Technol ; 58(6): 2447-2451, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33967341

RESUMEN

Hot-melt extrusion (HME) technology was employed to improve water dispersibility of phytosterol (P) using glycerol (G), lecithin (L), and gum arabic (A) as emulsifiers and stabilizers. The structural properties and water dispersibility of HME products were investigated. In contrast to physical mixtures, better water dispersibility and storage stability were observed for HME products, especially P:L:G:A extrudate. These improvements may be mainly associated with decreased crystallinity of phytosterol due to the occurrence of co-crystallization of phytosterol with glycerol during HME process, as confirmed by DSC and XRD data. In addition, HME-induced lecithin-arabic gum reaction products effectively stabilize phytosterol microparticle in aqueous dispersion by providing a steric hindrance. These results suggest that HME could be an effectively and potentially solvent-free technique to produce water-dispersible phytosterol on a large scale.

13.
J Sep Sci ; 43(12): 2264-2269, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32160411

RESUMEN

Amantadine plasma concentrations correlate well with desired therapeutic effects and adverse outcomes; information on amantadine exposure could be useful when multiple amantadine clearance pathways are impaired or non-compliance is suspected. Micro-sampling strategies, like dried plasma spot, would be particularly useful because ambulatory patients that do not attend a clinic can easily sample a few drops of blood by themselves at the required time of the dosing interval. We developed and validated a dried-plasma-spot-based high performance liquid chromatography-tandem mass spectrometry assay to quantify amantadine. This assay met relevant validation requirements within a hematocrit range of 20-50% and was linear from 100 to 2000 ng/mL. Amantadine was stable in dried plasma spots for up to 21 days at room temperature, regardless of whether the dried plasma spot was protected from light or not. The correlation between paired dried and wet plasma concentrations was assessed in 52 patients. Deming regression coefficients between wet plasma and simultaneously pipetted dried plasma spots were used to predict plasma concentrations. Bland-Altman plots revealed a strong agreement between dried and wet plasma concentrations, supporting the clinical usefulness of dried plasma spots for amantadine monitoring with a self-sampling strategy at a convenient time and place for the patient.


Asunto(s)
Amantadina/sangre , Pruebas con Sangre Seca , Amantadina/química , Cromatografía Líquida de Alta Presión , Humanos , Estructura Molecular , Espectrometría de Masas en Tándem
14.
Nano Lett ; 19(8): 5806-5817, 2019 08 14.
Artículo en Inglés | MEDLINE | ID: mdl-31331172

RESUMEN

Constructing a tumor microenvironment stimuli activatable theranostic nanoparticle with simple components and preparation procedures for multimodality imaging and therapy remains a major challenge for current theranostic systems. Here we report a novel and simple glutathione (GSH)-responsive turn-on theranostic nanoparticle for dual-modal imaging and combination therapy. The theranostic nanoparticle, DHP, consisting of a disulfide-bond-linked hydroxyethyl starch paclitaxel conjugate (HES-SS-PTX) and a near-infrared (NIR) cyanine fluorophore DiR, is prepared with a simple one-step dialysis method. As DiR is encapsulated within the hydrophobic core formed by HES-SS-PTX, the fluorescence of DiR is quenched by the aggregation-caused quenching (ACQ) effect. Nonetheless, once DHP is internalized by cancer cells, the disulfide bond of HES-SS-PTX can be cleaved by intracellular GSH, leading to the synchronized release of conjugated PTX and loaded DiR. The released PTX could exert its therapeutic effect, while DiR could adsorb onto nearby endosome/lysosome membranes and regain its fluorescence. Thus, DHP could monitor the release and therapeutic effect of PTX through the fluorescence recovery of DiR. Remarkably, DHP can also be used as an in vivo probe for both fluorescent and photoacoustic imaging and at the same time achieves potent antitumor efficacy through chemo-photothermal combination therapy. This study provides novel insights into designing clinically translatable turn-on theranostic systems.


Asunto(s)
Antineoplásicos Fitogénicos/uso terapéutico , Colorantes Fluorescentes/uso terapéutico , Glutatión/metabolismo , Nanopartículas/uso terapéutico , Neoplasias/terapia , Paclitaxel/uso terapéutico , Animales , Línea Celular Tumoral , Terapia Combinada , Hipertermia Inducida , Ratones , Ratones Endogámicos BALB C , Neoplasias/diagnóstico por imagen , Neoplasias/metabolismo , Imagen Óptica , Técnicas Fotoacústicas , Fototerapia , Nanomedicina Teranóstica
15.
Bioconjug Chem ; 30(4): 1199-1209, 2019 04 17.
Artículo en Inglés | MEDLINE | ID: mdl-30888794

RESUMEN

Noninvasive visualization of deep tissue lymphatic metastasis is crucial for diagnosing malignant tumors and predicting prognosis. However, the limited diffusivity and specificity of imaging contrast agents that are transported in lymph vessels (LVs), even for those agents delivered by nanocarriers, make long-distance tracing of the lymphatic system in vivo challenging. Here, we develop a computed tomography (CT)/fluorescence dual-modality phospholipid nanoprobe (PL(I/D)NP) with a negative charge and sub-60 nm size. By using micro-CT, we noninvasively traced the LVs from the subcutaneous injection site in feet to the thoracic ducts with an entire length of ∼68 mm and measured the volume of the lymph nodes (LNs) and their separation distance along the LVs. For diagnostic imaging of tumor lymphatic metastasis, all LNs with metastasis were identified in vivo. Thus, with their long-distance diffusivity, high lymphatic capillary specificity, and quantifiability, the PL(I/D)NPs combined with noninvasive imaging accurately depicted the changes in the lymphatic system under pathologic conditions, especially cancer metastasis, which indicates their high potential for clinical applicability.


Asunto(s)
Colorantes Fluorescentes/química , Metástasis Linfática/diagnóstico por imagen , Sistema Linfático/diagnóstico por imagen , Nanopartículas/química , Microtomografía por Rayos X/métodos , Animales , Medios de Contraste , Humanos , Sistema Linfático/anatomía & histología , Ratones
16.
J Exp Bot ; 70(2): 545-561, 2019 01 07.
Artículo en Inglés | MEDLINE | ID: mdl-30380099

RESUMEN

Manual phenotyping of rice tillers is time consuming and labor intensive, and lags behind the rapid development of rice functional genomics. Thus, automated, non-destructive methods of phenotyping rice tiller traits at a high spatial resolution and high throughput for large-scale assessment of rice accessions are urgently needed. In this study, we developed a high-throughput micro-CT-RGB imaging system to non-destructively extract 739 traits from 234 rice accessions at nine time points. We could explain 30% of the grain yield variance from two tiller traits assessed in the early growth stages. A total of 402 significantly associated loci were identified by genome-wide association study, and dynamic and static genetic components were found across the nine time points. A major locus associated with tiller angle was detected at time point 9, which contained a major gene, TAC1. Significant variants associated with tiller angle were enriched in the 3'-untranslated region of TAC1. Three haplotypes for the gene were found, and rice accessions containing haplotype H3 displayed much smaller tiller angles. Further, we found two loci containing associations with both vigor-related traits identified by high-throughput micro-CT-RGB imaging and yield. The superior alleles would be beneficial for breeding for high yield and dense planting.


Asunto(s)
Oryza/crecimiento & desarrollo , Oryza/genética , Biomasa , Sequías , Grano Comestible/crecimiento & desarrollo , Genoma de Planta , Estudio de Asociación del Genoma Completo , Microtomografía por Rayos X
17.
J Sci Food Agric ; 99(6): 3176-3185, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30548612

RESUMEN

BACKGROUND: During the last decade buckwheat was reported to have positive health effects. The present study investigated a high-polyphenol buckwheat protein (Fagopyrum esculentum Moench) prepared by enzyme-assisted processing, together with its physicochemical properties, in vitro digestibility, and antioxidant activity. RESULTS: Buckwheat protein prepared from the synergistic enzymatic action of α-amylase and amyloglucosidase (E-BWP) had much higher polyphenol content than buckwheat protein prepared by isoelectric precipitation (I-BWP) or salt extraction (S-BWP). Rutin degraded during the process, giving quercetin. The protein constituents and amino acid composition of E-BWP were very similar to those of native buckwheat and were able to meet the WHO/FAO requirements for both children and adults. During in vitro digestion, E-BWP showed anti-digestive behavior with a nitrogen release that was lower than that of I-BWP or S-BWP. The positive effect of the polyphenol content of E-BWP resulted in a higher 1,1-diphenyl-2-picrylhydrazyl (DPPH) content and greater reducing activity. CONCLUSION: Buckwheat protein with high polyphenol content was successfully developed by enzyme-assisted processing. It had a well-balanced amino acid profile, antidigestive behavior, and high antioxidant activities. The results suggest that enzyme-assisted processing is promising in the production of polyphenol-enriched cereal protein, contributing higher functionality with good nutritional and antioxidant properties. © 2018 Society of Chemical Industry.


Asunto(s)
Antioxidantes/química , Fagopyrum/química , Fagopyrum/metabolismo , Glucano 1,4-alfa-Glucosidasa/química , Proteínas de Plantas/química , Polifenoles/análisis , alfa-Amilasas/química , Antioxidantes/metabolismo , Biocatálisis , Digestión , Manipulación de Alimentos , Humanos , Proteínas de Plantas/metabolismo , Polifenoles/metabolismo , Semillas/química , Semillas/metabolismo
18.
J Food Sci Technol ; 56(2): 905-913, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30906048

RESUMEN

The complexation of corn protein hydrolyzate (CPH) with tannic acid (TA) was utilized to improve the foaming properties of CPH itself, and the air-water interfacial behavior of CPH-TA complex was also investigated. The results showed that the surface hydrophobicity of pure CPH was significantly decreased in bulk solution after the complexation with TA. Compared with pure CPH, the foams stabilized by CPH-TA complex showed higher interfacial thickness between the bubbles, which well explained the better long term stability of the corresponding foams. Therefore, the complexation maintained the good foaming capacity of CPH itself, but considerably increased its foam stability. Moreover, the air-water interfacial behavior study demonstrated that the complexation slightly decreased the interfacial activity of CPH itself, but considerably increased its interfacial viscoelasticity, suggesting more stable of the air-water interface stabilized by CPH-TA complex compared with that stabilized by CPH alone. These findings indicated that foaming properties of the surface active components were closely related with its air-water interfacial behavior. The study suggested that CPH-TA complex could be used as a stabilizer in constructing the peptides-based foams.

19.
Small ; 14(50): e1803602, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30370690

RESUMEN

By integrating the characteristics of each therapy modality and material chemistry, a multitherapy modality is put forward: tumor starvation triggered synergism with sensitized chemotherapy. Following starvation-induced amplification of pathological abnormalities in tumors, chemotherapy is arranged to be locally activated and accurately reinforced to perfect multitherapy synergism from spatial and temporal perspectives. To this end, glucose oxidase (GOD) and a hypoxic prodrug of tirapazamine (TPZ) are loaded in acidity-decomposable calcium carbonate (CaCO3 ) nanoparticles concurrently tethered by hyaluronic acid. This hybrid nanotherapeutic shows a strong tendency to accumulate in tumors postinjection due to the cooperation between passive and active targeting mechanisms. The GOD-driven oxidation reaction deprives tumors of glucose for starvation therapy and concomitantly induces tumorous abnormality amplifications including elevated acidity and exacerbated hypoxia. Programmatically, the acidity amplification causes CaCO3 decomposition, offering not only spatial control over the liberation of embedded TPZ just within tumors but also the temporal control over timely chemotherapy initiation to match the occurrence of hypoxia amplification and thus benefiting perfect synergism between starvation therapy and chemotherapy.


Asunto(s)
Antineoplásicos/química , Carbonato de Calcio/química , Nanopartículas/química , Profármacos/química , Tirapazamina/química , Glucosa Oxidasa/metabolismo , Ácido Hialurónico/química
20.
Langmuir ; 34(13): 3971-3980, 2018 04 03.
Artículo en Inglés | MEDLINE | ID: mdl-29546991

RESUMEN

Nanofibrils from the self-assembly of the naturally occurring saponin glycyrrhizic acid (GA) can be used to produce an oil-in-water emulsion foam with a long-term stability. Through homogenization and aeration followed by rapid cooling, stable emulsion foams can be produced from the mixtures of sunflower oil and saponin nanofibrils. At high temperatures, the GA fibrils form a multilayer assembly at the interface, creating an interfacial fibrillar network to stabilize the oil droplets and air bubbles generated during homogenization. A subsequent rapid cooling can trigger the self-assembly of free GA fibrils in the continuous phase, forming a fibrillar hydrogel and thus trapping the oil droplets and air bubbles. The viscoelastic bulk hydrogel showed a high yield stress and storage modulus, which lead to a complete arrest of the liquid drainage and a strong slowdown of the bubble coarsening in emulsion foams. The jamming of the emulsion droplets in the liquid channels as well as around the bubbles was also found to be able to enhance the foam stability. We show that such stable foam systems can be destroyed rapidly and on demand by heating because of the melting of the bulk hydrogel. The reversible gel-sol phase transition of the GA hydrogel leads to thermoresponsive emulsion foams, for which the foam stability can be switched from stable to unstable states by simply raising the temperature. The emulsion foams can be further developed to be photoresponsive by incorporating internal heat sources such as carbon black particles, which can absorb UV irradiation and convert the absorbed light energy into heat. This new class of smart responsive emulsion foams stabilized by the natural, sustainable saponin nanofibrils has potential applications in the food, pharmaceutical, and personal care industries.

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