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1.
Angew Chem Int Ed Engl ; 63(13): e202316664, 2024 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-38290006

RESUMEN

Nanoporous materials are of great interest in many applications, such as catalysis, separation, and energy storage. The performance of these materials is closely related to their pore sizes, which are inefficient to determine through the conventional measurement of gas adsorption isotherms. Nuclear magnetic resonance (NMR) relaxometry has emerged as a technique highly sensitive to porosity in such materials. Nonetheless, streamlined methods to estimate pore size from NMR relaxometry remain elusive. Previous attempts have been hindered by inverting a time domain signal to relaxation rate distribution, and dealing with resulting parameters that vary in number, location, and magnitude. Here we invoke well-established machine learning techniques to directly correlate time domain signals to BET surface areas for a set of metal-organic frameworks (MOFs) imbibed with solvent at varied concentrations. We employ this series of MOFs to establish a correlation between NMR signal and surface area via partial least squares (PLS), following screening with principal component analysis, and apply the PLS model to predict surface area of various nanoporous materials. This approach offers a high-throughput, non-destructive way to assess porosity in c.a. one minute. We anticipate this work will contribute to the development of new materials with optimized pore sizes for various applications.

2.
Nat Mater ; 20(7): 984-990, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33686276

RESUMEN

All-solid-state lithium (Li) metal and lithium-ion batteries (ASSLBs) with inorganic solid-state electrolytes offer improved safety for electric vehicles and other applications. However, current inorganic ASSLB manufacturing technology suffers from high cost, excessive amounts of solid-state electrolyte and conductive additives, and low attainable volumetric energy density. Such a fabrication method involves separate fabrications of sintered ceramic solid-state electrolyte membranes and ASSLB electrodes, which are then carefully stacked and sintered together in a precisely controlled environment. Here we report a disruptive manufacturing technology that offers reduced manufacturing costs and improved volumetric energy density in all solid cells. Our approach mimics the low-cost fabrication of commercial Li-ion cells with liquid electrolytes, except that we utilize solid-state electrolytes with low melting points that are infiltrated into dense, thermally stable electrodes at moderately elevated temperatures (~300 °C or below) in a liquid state, and which then solidify during cooling. Nearly the same commercial equipment could be used for electrode and cell manufacturing, which substantially reduces a barrier for industry adoption. This energy-efficient method was used to fabricate inorganic ASSLBs with LiNi0.33Mn0.33Co0.33O2 cathodes and both Li4Ti5O12 and graphite anodes. The promising performance characteristics of such cells open new opportunities for the accelerated adoption of ASSLBs for safer electric transportation.

3.
Nat Mater ; 18(12): 1343-1349, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31501555

RESUMEN

Metal fluoride conversion cathodes offer a pathway towards developing lower-cost Li-ion batteries. Unfortunately, such cathodes suffer from extremely poor performance at elevated temperatures, which may prevent their use in large-scale energy storage applications. Here we report that replacing commonly used organic electrolytes with solid polymer electrolytes may overcome this hurdle. We demonstrate long-cycle stability for over 300 cycles at 50 °C attained in high-capacity (>450 mAh g-1) FeF2 cathodes. The absence of liquid solvents reduced electrolyte decomposition, while mechanical properties of the solid polymer electrolyte enhanced cathode structural stability. Our findings suggest that the formation of an elastic, thin and homogeneous cathode electrolyte interphase layer on active particles is a key for stable performance. The successful operation of metal fluorides at elevated temperatures opens a new avenue for their practical applications and future successful commercialization.

4.
Angew Chem Int Ed Engl ; 59(1): 403-408, 2020 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-31604002

RESUMEN

Technologically important composites with enhanced thermal and mechanical properties rely on the reinforcement by the high specific strength ceramic nanofibers or nanowires (NWs) with high aspect ratios. However, conventional synthesis routes to produce such ceramic NWs have prohibitively high cost. Now, direct transformation of bulk Mg-Li alloys into Mg alkoxide NWs is demonstrated without the use of catalysts, templates, expensive or toxic chemicals, or any external stimuli. This mechanism proceeds through the minimization of strain energy at the boundary of phase transformation front leading to the formation of ultra-long NWs with tunable dimensions. Such alkoxide NWs can be easily converted in air into ceramic MgO NWs with similar dimensions. The impact of the alloy grain size and Li content, synthesis temperature, inductive and steric effects of alkoxide groups on the diameter, length, composition, ductility, and oxidation of the produced NWs is discussed.

5.
J Sci Food Agric ; 99(4): 1577-1585, 2019 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-30146707

RESUMEN

BACKGROUND: Red pepper flakes are often contaminated with various microorganisms; however, any technologies aiming to decontaminate the flakes should also maintain their quality properties. This study investigated the effect of microwave-combined cold plasma treatment (MCPT) at different microwave power densities on microbial inactivation and preservation of red pepper flakes. Red pepper flake samples inoculated with spores of Bacillus cereus or Aspergillus flavus and without inoculation were subjected to MCPT at 900 W for 20 min at either low microwave power density (LMCPT, 0.17 W m-2 ) or high microwave power density (HMCPT, 0.25 W m-2 ). RESULTS: The numbers of B. cereus and A. flavus spores on red pepper flakes after LMCPT and HMCPT were initially reduced by 0.7 ± 0.1 and 1.4 ± 0.3 log spores cm-2 and by 1.5 ± 0.3 and 1.5 ± 0.2 log spores cm-2 respectively and remained constant for 150 days at 25 °C. Immediately after HMCPT, the concentrations of capsaicin and ascorbic acid in the flakes were significantly lower than in untreated samples; however, no difference in concentration was detected during storage. Neither LMCPT nor HMCPT affected the antioxidant activity or color of the flakes during storage. LMCPT also did not affect the sensory properties and the concentrations of capsaicin and dihydrocapsaicin of the flakes, indicating its suitability in preserving their quality properties. CONCLUSION: MCPT may provide an effective non-thermal treatment for food preservation which can improve the microbial safety and stability of red pepper flakes while maintaining intact their qualitative properties. © 2018 Society of Chemical Industry.


Asunto(s)
Capsicum/microbiología , Conservación de Alimentos/métodos , Gases em Plasma/farmacología , Aspergillus flavus/efectos de los fármacos , Aspergillus flavus/crecimiento & desarrollo , Aspergillus flavus/efectos de la radiación , Bacillus cereus/efectos de los fármacos , Bacillus cereus/crecimiento & desarrollo , Bacillus cereus/efectos de la radiación , Capsaicina/análogos & derivados , Capsaicina/análisis , Capsicum/química , Conservación de Alimentos/instrumentación , Microondas , Esporas Bacterianas/efectos de los fármacos , Esporas Bacterianas/crecimiento & desarrollo , Esporas Bacterianas/efectos de la radiación
6.
J Am Chem Soc ; 140(39): 12493-12500, 2018 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-30189731

RESUMEN

Fabrication and applications of lightweight, high load-bearing, thermally stable composite materials would benefit greatly from leveraging the high mechanical strength of ceramic nanowires (NWs) over conventional particles or micrometer-scale fibers. However, conventional synthesis routes to produce NWs are rather expensive. Recently we discovered a novel method to directly convert certain bulk bimetallic alloys to metal-organic NWs at ambient temperature and pressure. This method was demonstrated by a facile transformation of polycrystalline aluminum-lithium (AlLi) alloy particles to aluminum alkoxide NWs, which can be further transformed to mechanically robust aluminum oxide (Al2O3) NWs. However, the transformation mechanisms have not been clearly understood. Here, we conducted advanced materials characterization (via electron microscopy and nuclear magnetic resonance spectroscopies) and chemo-mechanical modeling to elucidate key physical and chemical mechanisms responsible for NWs formation. We further demonstrated that the content of Li metal in the AlLi alloy could be reduced to about 4 wt % without compromising the success of the NWs synthesis. This new mechanistic understanding may open new avenues for large-scale, low-cost manufacturing of NWs and nanofibers for a broad range of composites and flexible ceramic membranes.

7.
ACS Appl Mater Interfaces ; 14(11): 13820-13827, 2022 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-35286060

RESUMEN

We report on a new synthesis pathway for Mg n-propoxide nanowires (NWs) from Mg ethoxide nanoparticles using a simple alkoxy ligand exchange reaction followed by condensation polymerization in n-propanol. In order to uncover the morphology-structure correlation in the metal alkoxide family, we employed a powerful range of state-of-the-art characterization techniques. The morphology transformation from nanoparticles to nanowires was demonstrated by time-lapse SEM micrographs. Fourier transform infrared spectroscopy (FTIR) and nuclear magnetic resonance spectroscopy (such as 1H NMR and solid-state 13C cross-polarization (CP)-MAS NMR) illustrated the replacement of ethyl by n-propyl and metal alkoxide condensation polymerization. We identified chemical formulas of the products also using NMR spectroscopy. The crystal structure simulation of Mg ethoxide particles and Mg n-propoxide NWs provided insights on how the ligand exchange and the associated increase in the fraction of OH groups greatly enhanced Mg alkoxide bonding and enabled a higher degree of coordination polymerization to facilitate the formation and growth of the Mg n-propoxide NWs. The discovered synthesis method could be extended for the fabrication of other metal alkoxide (nano) structures with various morphologies.

8.
Chem Mater ; 34(9): 3893-3901, 2022 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-35573112

RESUMEN

Mg-Al mixed metal oxides (MMOs), derived from the decomposition of layered double hydroxides (LDHs), have been purposed as adsorbents for CO2 capture of industrial plant emissions. To aid in the design and optimization of these materials for CO2 capture at 200 °C, we have used a combination of solid-state nuclear magnetic resonance (ssNMR) and density functional theory (DFT) to characterize the CO2 gas sorption products and determine the various sorption sites in Mg-Al MMOs. A comparison of the DFT cluster calculations with the observed 13C chemical shifts of the chemisorbed products indicates that mono- and bidentate carbonates are formed at the Mg-O sites with adjacent Al substitution of an Mg atom, while the bicarbonates are formed at Mg-OH sites without adjacent Al substitution. Quantitative 13C NMR shows an increase in the relative amount of strongly basic sites, where the monodentate carbonate product is formed, with increasing Al/Mg molar ratios in the MMOs. This detailed understanding of the various basic Mg-O sites presented in MMOs and the formation of the carbonate, bidentate carbonate, and bicarbonate chemisorbed species yields new insights into the mechanism of CO2 adsorption at 200 °C, which can further aid in the design and capture capacity optimization of the materials.

9.
Nanotechnology ; 22(5): 055701, 2011 Feb 04.
Artículo en Inglés | MEDLINE | ID: mdl-21178225

RESUMEN

The Fe(3)O(4)-Ca(3)(PO(4))(2) core-shell nanoparticles were prepared by one-pot non-aqueous nanoemulsion with the assistance of a biocompatible triblock copolymer, poly(ethylene glycol)-block-poly(propylene glycol)-block-poly(ethylene glycol) (PEO-PPO-PEO), integrating the magnetic properties of Fe(3)O(4) and the bioactive functions of Ca(3)(PO(4))(2) into single entities. The Fe(3)O(4) nanoparticles were pre-formed first by thermal reduction of Fe(acac)(3) and then the Ca(3)(PO(4))(2) layer was coated by simultaneous deposition of Ca(2+) and PO(4)(3-). The characterization shows that the combination of the two materials into a core-shell nanostructure retains the magnetic properties and the Ca(3)(PO(4))(2) shell forms an hcp phase (a = 7.490 Å, c = 9.534 Å) on the Fe(3)O(4) surface. The magnetic hysteresis curves of the nanoparticles were further elucidated by the Langevin equation, giving an estimation of the effective magnetic dimension of the nanoparticles and reflecting the enhanced susceptibility response as a result of the surface covering. Fourier transform infrared (FTIR) analysis provides the characteristic vibrations of Ca(3)(PO(4))(2) and the presence of the polymer surfactant on the nanoparticle surface. Moreover, the nanoparticles could be directly transferred to water and the aqueous dispersion-collection process of the nanoparticles was demonstrated for application readiness of such core-shell nanostructures in an aqueous medium. Thus, the construction of Fe(3)O(4) and Ca(3)(PO(4))(2) in the core-shell nanostructure has conspicuously led to enhanced performance and multi-functionalities, offering various possible applications of the nanoparticles.

10.
Eur Spine J ; 20(8): 1297-303, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21249507

RESUMEN

Even though a number of studies have evaluated postural adjustments based on kinematic changes in subjects with low back pain (LBP), kinematic stability has not been examined for abnormal postural responses during the one leg standing test. The purpose of this study was to evaluate the relative kinematic stability of the lower extremities and standing duration in subjects with and without chronic LBP. In total, 54 subjects enrolled in the study, including 28 subjects without LBP and 26 subjects with LBP. The average age of the subjects was 37.8 ± 12.6 years and ranged from 19 to 63 years. The outcome measures included normalized holding duration and relative kinematic stability. All participants were asked to maintain the test position without visual input (standing on one leg with his/her eyes closed and with the contra lateral hip flexed 90°) for 25 s. The age variable was used as a covariate to control confounding effects for the data analyses. The control group demonstrated significantly longer holding duration times (T = -2.78, p = 0.007) than the LBP group (24.6 ± 4.2 s vs. 20.5 ± 6.7 s). For the relative kinematic stability, there was a difference in dominance side (F = 9.91, p = 0.003). There was a group interaction between side and lower extremities (F = 11.79, p = 0.001) as well as an interaction between age and dominance side (F = 7.91, p = 0.007). The relative kinematic stability had a moderate negative relationship with age (r = -0.60, p = 0.007) in subjects without LBP. Clinicians need to understand the effects of age and relative stability, which decreased significantly in the single leg holding test, in subjects with LBP in order to develop effective rehabilitation strategies.


Asunto(s)
Fenómenos Biomecánicos/fisiología , Dolor Crónico/fisiopatología , Evaluación de la Discapacidad , Trastornos Neurológicos de la Marcha/fisiopatología , Dolor de la Región Lumbar/fisiopatología , Equilibrio Postural/fisiología , Adulto , Dolor Crónico/diagnóstico , Femenino , Trastornos Neurológicos de la Marcha/diagnóstico , Trastornos Neurológicos de la Marcha/etiología , Humanos , Pierna/fisiopatología , Dolor de la Región Lumbar/complicaciones , Dolor de la Región Lumbar/diagnóstico , Masculino , Persona de Mediana Edad , Soporte de Peso/fisiología , Adulto Joven
11.
ACS Appl Mater Interfaces ; 13(36): 42370-42381, 2021 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-34486371

RESUMEN

Natural killer (NK) cells serve as key innate effectors and their activity has been considered a prognostic biomarker in diverse human diseases. Currently, NK cell functional assays have several problems primarily related to adequate preparation, labeling, or treatment of target cells, which are cumbersome and often hamper consistent sensitivity for NK cells. Here, bispecific antibodies (BsAb's) targeting NKG2D and 2B4 receptors, whose combination mounts selective cytotoxicity and IFN-γ production of NK cells, are developed as acellular, consistent, and easy-to-use strategies for assessing NK cell functions. These NK cell activator BsAb's (NKABs) are constructed in symmetric dual bivalent formats with different interdomain spacings [immunoglobulin G (IgG)-single-chain variable fragment (scFv) and dual-variable domain (DVD)-Ig] and kappa constant (Cκ)-scFv format linking two scFv's with a Cκ domain. These NKABs are specific and superior to a combination of monospecific antibodies for NK cell activation. NKAB elicits both direct cytotoxicity and IFN-γ production via integration of NKG2D and 2B4 signals. Moreover, stimulation with NKAB IgG-scFv and Cκ-scFv reveals defective NK cell functions in X-linked lymphoproliferative disease involving 2B4 dysfunction in NK cells and multiple myeloma in peripheral blood mononuclear cells and whole blood, respectively. Hence, this work provides a proof of concept that NKAB facilitates the reliable and comprehensive measurement of NK cell function in clinical settings for diagnostic and prognostic purposes.


Asunto(s)
Anticuerpos Biespecíficos/inmunología , Células Asesinas Naturales/metabolismo , Activación de Linfocitos/inmunología , Subfamilia K de Receptores Similares a Lectina de Células NK/inmunología , Familia de Moléculas Señalizadoras de la Activación Linfocitaria/inmunología , Células HEK293 , Humanos , Interferón gamma/metabolismo , Células Asesinas Naturales/inmunología , Trastornos Linfoproliferativos/diagnóstico , Trastornos Linfoproliferativos/inmunología , Mieloma Múltiple/diagnóstico , Mieloma Múltiple/inmunología , Prueba de Estudio Conceptual , Anticuerpos de Cadena Única/inmunología
12.
ACS Sens ; 6(3): 693-697, 2021 03 26.
Artículo en Inglés | MEDLINE | ID: mdl-33606518

RESUMEN

Natural killer (NK) cells are a subset of innate lymphoid cells playing an important role in immune surveillance and early defense against infection and cancer. They recognize and directly kill infected or transformed cells. At the same time, they produce various cytokines and chemokines to regulate other immune cells. NK cell activity can be a useful marker for health screenings because impaired NK cell functions may indicate a more susceptible environment for infection or tumor development. Currently, most NK cell activity assays are focused on measuring either cytokine secretion, in particular, interferon γ (IFN-γ), or cytotoxicity against target cells such as K562, thus only providing partial information on NK cell activity. In order to develop a comprehensive test for measuring NK cell function, cytotoxicity and cytokine secretion ability should be measured simultaneously. In addition, current NK cell assays are performed by stimulating NK cells with cocktails of cytokines, antibody-coated beads, or live target cells. In this study, we developed multifunctional microparticles for NK cell activity assay (MNAs) that allow simultaneous stimulation and sensing various NK cell activities, including cytokine secretion and cytotoxicity. The surfaces of MNAs are decorated with multiple functional biomolecules, including antibodies that stimulate NK cells by engaging NK cell activating receptors, antibodies that can capture cytokines secreted by NK cells, and a peptide sensor that reacts with granzyme B, a key molecule released by NK cells for cytotoxicity. The performances of MNAs are assessed using flow cytometry and live cell imaging. NK cell activity is measured by simply mixing MNAs with NK cells and performing flow cytometry, and the results are comparable to those measured by standard NK cell activity assays.


Asunto(s)
Inmunidad Innata , Células Asesinas Naturales , Citocinas , Citometría de Flujo , Interferón gamma
13.
Nutrients ; 12(4)2020 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-32344605

RESUMEN

Kokumi taste substances exemplified by γ-glutamyl peptides and Maillard Peptides modulate salt and umami tastes. However, the underlying mechanism for their action has not been delineated. Here, we investigated the effects of a kokumi taste active and inactive peptide fraction (500-10,000 Da) isolated from mature (FIIm) and immature (FIIim) Ganjang, a typical Korean soy sauce, on salt and umami taste responses in humans and rodents. Only FIIm (0.1-1.0%) produced a biphasic effect in rat chorda tympani (CT) taste nerve responses to lingual stimulation with 100 mM NaCl + 5 µM benzamil, a specific epithelial Na+ channel blocker. Both elevated temperature (42 °C) and FIIm produced synergistic effects on the NaCl + benzamil CT response. At 0.5% FIIm produced the maximum increase in rat CT response to NaCl + benzamil, and enhanced salt taste intensity in human subjects. At 2.5% FIIm enhanced rat CT response to glutamate that was equivalent to the enhancement observed with 1 mM IMP. In human subjects, 0.3% FIIm produced enhancement of umami taste. These results suggest that FIIm modulates amiloride-insensitive salt taste and umami taste at different concentration ranges in rats and humans.


Asunto(s)
Peces/fisiología , Sodio/metabolismo , Papilas Gustativas/metabolismo , Gusto/fisiología , Animales , Fenómenos Electrofisiológicos , Humanos , Ratones , Modelos Animales , Ratas , Cloruro de Sodio Dietético , Gusto/efectos de los fármacos , Percepción del Gusto/efectos de los fármacos
14.
Front Immunol ; 10: 1354, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31281312

RESUMEN

Natural killer (NK) cells are key effectors in cancer immunosurveillance and can be used as a prognostic biomarker in diverse cancers. Nonetheless, the role of NK cells in pancreatic cancer (PC) remains elusive, given conflicting data on their association with disease prognosis. In this study, using conventional K562 target cells and complementary engineered target cells providing defined and synergistic stimulation for NK cell activation, a correlation between impaired NK cell cytotoxic degranulation and PC progression was determined. Peripheral blood mononuclear cells (PBMCs) from 31 patients with newly diagnosed PC, 24 patients with non-malignant tumors, and 37 healthy controls were analyzed by flow cytometry. The frequency, phenotype, and effector functions of the NK cells were evaluated, and correlations between NK cell functions and disease stage and prognosis were analyzed. The results demonstrated that effector functions, but not frequency, of NK cells was progressively decreased on a per-cell basis during PC progression. Impaired cytotoxic degranulation, but not IFN-γ production, was associated with clinical features indicating disease progression, such as high serum CA19-9 and high-grade tumors. Significantly, this impairment correlated with cancer recurrence and mortality in a prospective analysis. Furthermore, the impaired cytotoxic degranulation was unrelated to NKG2D downregulation but was associated with increased circulating and tumor-associated TGF-ß1 expression. Thus, NK cell cytotoxic activity was associated with PC progression and may be a favorable biomarker with predictive and prognostic value in PC.


Asunto(s)
Biomarcadores de Tumor/inmunología , Células Asesinas Naturales/inmunología , Neoplasias Pancreáticas/inmunología , Neoplasias Pancreáticas/patología , Factor de Crecimiento Transformador beta1/inmunología , Degranulación de la Célula/inmunología , Citotoxicidad Inmunológica/inmunología , Progresión de la Enfermedad , Humanos , Células Asesinas Naturales/patología
15.
Int Immunopharmacol ; 67: 152-159, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30551032

RESUMEN

This study identified 8-azaguanine (8-AG) as a novel immunomodulatory drug (IMiD) through a high-throughput screen of the Preswick Chemical Library in a model of human NK cell cytotoxicity against blood cancer cells. 8-AG, originally developed as an antineoplastic agent, significantly increased the cytotoxicity of NK cells and was superior in this activity to previously known IMiDs, such as fluoxetine and amphotericin B, identified from the same library. IFN-γ expression was also slightly increased by 8-AG. Mechanistically, 8-AG increased conjugate formation between NK and target cells and subsequent cytolytic granule polarization, but not calcium mobilization, regulation of activating receptors, or expression of perforin or granzyme B. Thus, the antineoplastic activity of 8-AG should be re-evaluated in light of this novel potentiating effect on NK cells.


Asunto(s)
Antineoplásicos/uso terapéutico , Azaguanina/uso terapéutico , Neoplasias Hematológicas/tratamiento farmacológico , Factores Inmunológicos/uso terapéutico , Células Asesinas Naturales/inmunología , Anfotericina B/uso terapéutico , Células Cultivadas , Gránulos Citoplasmáticos/metabolismo , Citotoxicidad Inmunológica , Ensayos de Selección de Medicamentos Antitumorales , Fluoxetina/uso terapéutico , Granzimas/metabolismo , Humanos , Activación de Linfocitos , Perforina/genética , Perforina/metabolismo , Bibliotecas de Moléculas Pequeñas
16.
J Food Sci ; 83(4): 1011-1016, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29577288

RESUMEN

Films containing microencapsulated cinnamon oil (CO) were developed using a large-scale production system to protect against the Indian meal moth (Plodia interpunctella). CO at concentrations of 0%, 0.8%, or 1.7% (w/w ink mixture) was microencapsulated with polyvinyl alcohol. The microencapsulated CO emulsion was mixed with ink (47% or 59%, w/w) and thinner (20% or 25%, w/w) and coated on polypropylene (PP) films. The PP film was then laminated with a low-density polyethylene (LDPE) film on the coated side. The film with microencapsulated CO at 1.7% repelled P. interpunctella most effectively. Microencapsulation did not negatively affect insect repelling activity. The release rate of cinnamaldehyde, an active repellent, was lower when CO was microencapsulated than that in the absence of microencapsulation. Thermogravimetric analysis exhibited that microencapsulation prevented the volatilization of CO. The tensile strength, percentage elongation at break, elastic modulus, and water vapor permeability of the films indicated that microencapsulation did not affect the tensile and moisture barrier properties (P > 0.05). The results of this study suggest that effective films for the prevention of Indian meal moth invasion can be produced by the microencapsulation of CO using a large-scale film production system. PRACTICAL APPLICATION: Low-density polyethylene-laminated polypropylene films printed with ink incorporating microencapsulated cinnamon oil using a large-scale film production system effectively repelled Indian meal moth larvae. Without altering the tensile and moisture barrier properties of the film, microencapsulation resulted in the release of an active repellent for extended periods with a high thermal stability of cinnamon oil, enabling commercial film production at high temperatures. This anti-insect film system may have applications to other food-packaging films that use the same ink-printing platform.


Asunto(s)
Acroleína/análogos & derivados , Embalaje de Alimentos/métodos , Conservación de Alimentos/métodos , Repelentes de Insectos , Mariposas Nocturnas , Aceites Volátiles , Polietileno , Acroleína/química , Acroleína/farmacología , Animales , Composición de Medicamentos , Emulsiones , Humanos , Repelentes de Insectos/química , Repelentes de Insectos/farmacología , Insectos/efectos de los fármacos , Larva , Mariposas Nocturnas/efectos de los fármacos , Aceites Volátiles/química , Aceites Volátiles/farmacología , Permeabilidad , Polipropilenos , Alcohol Polivinílico , Temperatura , Resistencia a la Tracción
17.
Front Immunol ; 9: 2785, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30546365

RESUMEN

Ginsenosides are the principal active components of ginseng and are considered attractive candidates for combination cancer therapy because they can kill tumors and have favorable safety profiles. However, the overall benefit of ginsenosides remains unclear, particularly in cancer immunosurveillance, considering the controversial results showing repression or promotion of immune responses. Here we identify a potentiating role of ginsenoside F1 (G-F1) in cancer surveillance by natural killer (NK) cells. Among 15 different ginsenosides, G-F1 most potently enhanced NK cell cytotoxicity in response to diverse activating receptors and cancer cells. G-F1 also improved cancer surveillance in mouse models of lymphoma clearance and metastatic melanoma that rely on NK cell activity. G-F1-treated NK cells exhibited elevated cytotoxic potential such as upregulation of cytotoxic mediators and of activation signals upon stimulation. NK cell potentiation by G-F1 was antagonized by insulin-like growth factor (IGF)-1 blockade and recapitulated by IGF-1 treatment, suggesting the involvement of IGF-1. Thus, our results suggest that G-F1 enhances NK cell function and may have chemotherapeutic potential in NK cell-based immunotherapy. We anticipate our results to be a starting point for further comprehensive studies of ginsenosides in the immune cells mediating cancer surveillance and the development of putative therapeutics.


Asunto(s)
Ginsenósidos/farmacología , Inmunidad Celular/efectos de los fármacos , Factor I del Crecimiento Similar a la Insulina/inmunología , Células Asesinas Naturales , Linfoma , Neoplasias Experimentales , Animales , Humanos , Inmunoterapia , Células Asesinas Naturales/inmunología , Células Asesinas Naturales/patología , Linfoma/inmunología , Linfoma/patología , Linfoma/terapia , Ratones , Neoplasias Experimentales/inmunología , Neoplasias Experimentales/terapia
18.
J Food Sci ; 81(1): E86-96, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26646616

RESUMEN

The effects of cold plasma (CP) treatment on the physicochemical and biodegradable properties of polylactic acid (PLA) films were studied. The PLA films were exposed to CP for 40 min at 900 W and 667 Pa using oxygen as the plasma-forming gas. The tensile, optical, and dynamic mechanical thermal properties, surface morphology, printability, water contact angle, chemical structure, weight change, and biodegradability properties of the films were evaluated during storage for up to 56 d. The tensile and optical properties of the PLA films were not significantly affected by CP treatment (CPT; P > 0.05). The surface roughness and water contact angle of PLA films increased by CPT and further increased during storage for 56 d. The printability of the PLA films increased following CPT and remained stable throughout the storage period. CP-induced hydrophilicity was also sustained during the storage period. The PLA films lost 1.9% of their weight after CPT, but recovered 99.5% of this loss after 14 d in storage. Photodegradation, thermal, and microbial biodegradable properties of the films were significantly improved by CPT (P < 0.05). Accelerated biodegradation of CP-treated PLA sachets with and without cheese was observed in compost. These results demonstrate the potential of CPT for modifying the stiffness, water contact angle, and chemical structure of PLA films and improving the printability and biodegradability of the films for food packaging.


Asunto(s)
Plásticos Biodegradables , Embalaje de Alimentos/métodos , Almacenamiento de Alimentos/métodos , Ácido Láctico/química , Oxígeno/química , Gases em Plasma/química , Polímeros/química , Queso , Conservación de Alimentos/métodos , Interacciones Hidrofóbicas e Hidrofílicas , Poliésteres , Suelo , Resistencia a la Tracción , Agua/química
19.
J Food Sci ; 79(10): E2023-30, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25250888

RESUMEN

UNLABELLED: Insect-resistant laminate films containing microencapsulated cinnamon oil (CO) were developed to protect food products from the Indian meal moth (Plodia interpunctella). CO microencapsulated with polyvinyl alcohol was incorporated with a printing ink and the ink mixture was applied to a low-density polyethylene (LDPE) film as an ink coating. The coated LDPE surface was laminated with a polypropylene film. The laminate film impeded the invasion of moth larvae and repelled the larvae. The periods of time during which cinnamaldehyde level in the film remained above a minimum repelling concentration, predicted from the concentration profile, were 21, 21, and 10 d for cookies, chocolate, and caramel, respectively. Coating with microencapsulated ink did not alter the tensile or barrier properties of the laminate film. Microencapsulation effectively prevented volatilization of CO. The laminate film can be produced by modern film manufacturing lines and applied to protect food from Indian meal moth damage. PRACTICAL APPLICATION: The LDPE-PP laminate film developed using microencapsulated cinnamon oil was effective to protect the model foods from the invasion of Indian meal moth larvae. The microencapsulated ink coating did not significantly change the tensile and barrier properties of the LDPE-PP laminate film, implying that replacement of the uncoated with coated laminate would not be an issue with current packaging equipment. The films showed the potential to be produced in commercial film production lines that usually involve high temperatures because of the improved thermal stability of cinnamon oil due to microencapsulation. The microencapsulated system may be extended to other food-packaging films for which the same ink-printing platform is used.


Asunto(s)
Cinnamomum zeylanicum/química , Embalaje de Alimentos , Mariposas Nocturnas/fisiología , Aceites de Plantas/farmacología , Polietileno/química , Animales , Composición de Medicamentos , Larva , Aceites de Plantas/química , Polipropilenos/química
20.
Physiotherapy ; 98(2): 160-6, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22507367

RESUMEN

OBJECTIVE: To investigate three-dimensional angular changes of the pelvis and lower extremities during trunk axial rotation in subjects with and without chronic low back pain (LBP). DESIGN: Repeated-measures design. PARTICIPANTS: Thirty volunteers participated in the study (15 with LBP, 15 without LBP). The mean age of the subjects was 44 (standard deviation 15.8) years (range 27 to 63 years). MAIN OUTCOME MEASURES: All participants were asked to perform five sets of axial trunk rotation activities with a bar in a standing position. The outcome measures included three-dimensional rotational angles of the pelvis and lower extremities (foot, calf and thigh). RESULTS: The angular change of the pelvis in the sagittal plane differed between subjects with and without LBP (P=0.03). There were no significant differences in angular changes of the lower extremities in the frontal and transverse planes between groups. CONCLUSIONS: The angular change of the pelvis in the sagittal plane differed significantly between groups. Further research is needed to investigate the three-dimensional characteristics of biomechanical and neuromuscular aspects in subjects with LBP.


Asunto(s)
Dolor de la Región Lumbar/fisiopatología , Extremidad Inferior/fisiología , Pelvis/fisiología , Rotación , Adulto , Fenómenos Biomecánicos , Enfermedad Crónica , Femenino , Humanos , Masculino , Persona de Mediana Edad , Equilibrio Postural , Postura
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