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501.
502.
Effects of annealing on the physicochemical properties and enzymatic susceptibility of rice starches with different amylose contents 总被引:1,自引:0,他引:1
Alvaro Renato Guerra Dias Elessandra da Rosa Zavareze Franciela Spier Luis Antonio Suita de Castro Luiz Carlos Gutkoski 《Food chemistry》2010
This study investigated the effects of annealing (ANN) on the properties of rice starches with high, medium and low-amylose contents. The starches were heated with excess water at 45 °C, 50 °C and 55 °C for 16 h. The swelling power, solubility, pasting properties, enzymatic susceptibility, morphology and X-ray crystallinity of the starches were evaluated. Annealing reduced the swelling power and solubility of the starches. ANN at 55 °C increased the pasting temperature and decreased the peak viscosity of the high-amylose rice starch. However, annealing decreased the peak viscosity of the low-amylose starch. The annealed rice starches presented a lower final viscosity and setback than did the native starches, with the exception of the low-amylose starch, which showed an increase in setback. Annealing increased the starches’ susceptibilities to α-amylase and promoted a reduction in their relative crystallinity. 相似文献
503.
Elessandra da Rosa Zavareze Cátia Regina Storck Luis Antonio Suita de Castro Manoel Artigas Schirmer Alvaro Renato Guerra Dias 《Food chemistry》2010
The effect of heat-moisture treatment (HMT) on the properties of rice starches with high-, medium- and low-amylose content was investigated. The starches were adjusted to 15%, 20% and 25% moisture levels, and heated at 110 °C for 1 h. The swelling power, solubility, pasting properties, morphology, enzymatic susceptibility and X-ray crystallinity of the starches were evaluated. HMT reduced the swelling power and solubility of the starches. The strongest effect of HMT occurred on the high-amylose starch; the pasting temperature was increased and the peak viscosity, breakdown, final viscosity and the setback were reduced. HMT increased the starch’s susceptibility to α-amylase and promoted a reduction in the starch relative crystallinity. 相似文献
504.
International development programing is increasingly integrating agriculture and nutrition goals, while attempting to demonstrate ‘impacts at scale’ and value for money. These multiple goals create complexities, both from a conceptual viewpoint and a more operational perspective. This article uses systems theory to examine the mobile Nutrition program (mNutrition), which aims to improve nutrition, food security and livelihoods for rural women and children, through mobile phone-based information services. The paper specifically uses mNutrition’s work in Malawi as a case study. The systems approach reveals that, as a complex system with numerous sub-components and tensions among different goals, the mNutrition program tended to minimize connections between its sub-systems (such as content development and mobile service development processes) in order to speed up movement towards the global planned outcomes. We argue that this is likely to have multiple impacts on outcomes, including on overall effectiveness and the relevance and sustainability of the mobile message content. 相似文献
505.
Clare Murray Eva Galvan Carlos Ontiveros Yilun Deng Haiyan Bai Alvaro Souto Padron Kathryn Hinchee-Rodriguez Myrna G. Garcia Anand Kornepati Jose Conejo-Garcia Tyler J. Curiel 《International journal of molecular sciences》2022,23(9)
The interaction between tumor surface-expressed PDL1 and immune cell PD1 for the evasion of antitumor immunity is well established and is targeted by FDA-approved anti-PDL1 and anti-PD1 antibodies. Nonetheless, recent studies highlight the immunopathogenicity of tumor-intrinsic PDL1 signals that can contribute to the resistance to targeted small molecules, cytotoxic chemotherapy, and αPD1 immunotherapy. As genetic PDL1 depletion is not currently clinically tractable, we screened FDA-approved drugs to identify those that significantly deplete tumor PDL1. Among the candidates, we identified the β-lactam cephalosporin antibiotic cefepime as a tumor PDL1-depleting drug (PDD) that increases tumor DNA damage and sensitivity to DNA-damaging agents in vitro in distinct aggressive mouse and human cancer lines, including glioblastoma multiforme, ovarian cancer, bladder cancer, and melanoma. Cefepime reduced tumor PDL1 post-translationally through ubiquitination, improved DNA-damaging-agent treatment efficacy in vivo in immune-deficient and -proficient mice, activated immunogenic tumor STING signals, and phenocopied specific genetic PDL1 depletion effects. The β-lactam ring and its antibiotic properties did not appear contributory to PDL1 depletion or to these treatment effects, and the related cephalosporin ceftazidime produced similar effects. Our findings highlight the rapidly translated potential for PDDs to inhibit tumor-intrinsic PDL1 signals and improve DNA-damaging agents and immunotherapy efficacy. 相似文献
506.
Esther Marhuenda Alvaro Villarino Maria Leonor Narciso Marta Camprubí-Rimblas Ramon Farr Núria Gavara Antonio Artigas Isaac Almendros Jorge Otero 《International journal of molecular sciences》2022,23(9)
One of the main limitations of in vitro studies on lung diseases is the difficulty of maintaining the type II phenotype of alveolar epithelial cells in culture. This fact has previously been related to the translocation of the mechanosensing Yes-associated protein (YAP) to the nuclei and Rho signaling pathway. In this work, we aimed to culture and subculture primary alveolar type II cells on extracellular matrix lung-derived hydrogels to assess their suitability for phenotype maintenance. Cells cultured on lung hydrogels formed monolayers and maintained type II phenotype for a longer time as compared with those conventionally cultured. Interestingly, cells successfully grew when they were subsequently cultured on a dish. Moreover, cells cultured on a plate showed the active form of the YAP protein and the formation of stress fibers and focal adhesions. The results of chemically inhibiting the Rho pathway strongly suggest that this is one of the mechanisms by which the hydrogel promotes type II phenotype maintenance. These results regarding protein expression strongly suggest that the chemical and biophysical properties of the hydrogel have a considerable impact on the transition from ATII to ATI phenotypes. In conclusion, culturing primary alveolar epithelial cells on lung ECM-derived hydrogels may facilitate the prolonged culturing of these cells, and thus help in the research on lung diseases. 相似文献
507.
Mukesh Kumar Thakur Golam Haider Farjana J. Sonia Jan Plšek Alvaro Rodriguez Vipin Mishra Jaganandha Panda Ondrej Gedeon Martin Mergl Oleksandr Volochanskyi Václav Valeš Otakar Frank Jana Vejpravova Martin Kalbáč 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(12):2205575
Tailoring the physicochemical properties of graphene through functionalization remains a major interest for next-generation technological applications. However, defect formation due to functionalization greatly endangers the intrinsic properties of graphene, which remains a serious concern. Despite numerous attempts to address this issue, a comprehensive analysis has not been conducted. This work reports a two-step fluorination process to stabilize the fluorinated graphene and obtain control over the fluorination-induced defects in graphene layers. The structural, electronic and isotope-mass-sensitive spectroscopic characterization unveils several not-yet-resolved facts, such as fluorination sites and C F bond stability in partially-fluorinated graphene (F-SLG). The stability of fluorine has been correlated to fluorine co-shared between two graphene layers in fluorinated-bilayer-graphene (F-BLG). The desorption energy of co-shared fluorine is an order of magnitude higher than the C F bond energy in F-SLG due to the electrostatic interaction and the inhibition of defluorination in the F-BLG. Additionally, F-BLG exhibits enhanced light–matter interaction, which has been utilized to design a proof-of-concept field-effect phototransistor that produces high photocurrent response at a time <200 µs. Thus, the study paves a new avenue for the in-depth understanding and practical utilization of fluorinated graphenic carbon. 相似文献
508.
509.
Massimo Frangiamone Manuel Lozano Alessandra Cimbalo Alvaro Lazaro Guillermina Font Lara Manyes 《Molecular nutrition & food research》2023,67(19):2200902
Scope
The aim of the study is to investigate in Jurkat cells the possible beneficial effect of pumpkin (P) and fermented milk whey (FW) mixture against aflatoxin B1 (AFB1) and ochratoxin A (OTA) induced alterations in gene expression profile.Methods and results
Human T cells are exposed for 7 days to digested bread extracts containing P-FW mixture along with AFB1 and OTA, individually and in combination. The results of RNA sequencing show that AFB1 P-FW exposure resulted in 34 differentially expressed genes (DEGs) while 3450 DEGs are found in OTA P-FW exposure and 3264 DEGs in AFB1-OTA P-FW treatment. Gene ontology analysis reveals biological processes and molecular functions related to immune system and inflammatory response. Moreover, PathVisio analysis points to eicosanoid signaling via lipoxygenase as the main pathway altered by AFB1 P-FW exposure whereas interferon signaling is the most affected pathway after OTA P-FW and AFB1-OTA P-FW treatments.Conclusions
The mitigation of genes and inherent pathways typically associated with the inflammatory response suggest not only the anti-inflammatory and protective role of P-FW mixture but also their possible application in food industry to counteract AFB1 and OTA toxic effects on human and animal health. 相似文献510.
Jose Angel Pariente Farzaneh Bayat Alvaro Blanco Antonio García-Martín Carlos Pecharromán Manuel I. Marqués Cefe López 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(40):2302355
By preparing colloidal crystals with random missing scatterers, crystals are created where disorder is embodied as vacancies in an otherwise perfect lattice. In this special system, there is a critical defect concentration where light propagation undergoes a transition from an all but perfect reflector (for the spectral range defined by the Bragg condition), to a metamaterial exhibiting an enhanced transmission phenomenon. It is shown that this behavior can be phenomenologically described in terms of Fano-like resonances. The results show that the Fano's parameter q experiences a sign change signaling the transition from a perfect crystal exhibiting a reflectance Bragg peak, through a state where background scattering is maximum and Bragg reflectance reaches a minimum to a point where the system reenters a low scattering state recovering ordinary Bragg diffraction. A simple dipolar model considering the correlation between scatterers and vacancies is proposed and the reported evolution of the Fano-like scattering is explained in terms of the emerging covariance between the optical paths and polarizabilities and the effect of field enhancement in photonic crystal (PhC) defects. 相似文献