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1.
Food Chem ; 457: 139708, 2024 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-38936135

RESUMEN

This study investigated the degradation of aflatoxin B1 (AFB1) in food by using dual-frequency ultrasound (DFUS) and the effects of sonochemical oxidation on the efficacy. It was found that the degradation of AFB1 by bath ultrasound (BU), probe ultrasound (PU), and DFUS were all consistent with first-order kinetics. The use of DFUS significantly increased the AFB1 degradation to 91.3%, and compared with BU and PU, it increased by about 177.0% and 61.5% after 30 min treatment. DFUS could generate a synergistic effect to accelerate the generation of free radicals, which promoted sonochemical oxidation to degrade AFB1. It could be speculated that hydroxyl radical (·OH) probably acted a dominant part in the AFB1 degradation by DFUS, and the hydrogen atoms (·H) might also are contributed. These results indicated that DFUS was an effective method of AFB1 degradation.

2.
Ann Surg Oncol ; 31(6): 3894-3905, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38494564

RESUMEN

OBJECTIVE: The objective of our study was to integrate the efficacy results of post-nephrectomy adjuvant therapies in renal cell carcinoma (RCC) patients with risk of recurrence, and attempt to determine the optimal intervention choice. METHODS: We performed standard meta-analysis procedures in compliance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The PubMed, Embase, and Cochrane Library databases were searched from inception to 22 September 2022. Randomized controlled trials reporting overall survival (OS) or disease-free survival (DFS) of adjuvant therapies, including immune checkpoint inhibitors (ICIs) and targeted therapies, in adult post-nephrectomy RCC patients were eligible for inclusion. RESULTS: Seven studies involving 7548 participants were included in our analyses. In contrast with placebo, DFS benefit with ICIs was only observed in female RCC patients and RCC patients with high programmed death-ligand 1 (PD-L1) expression (≥ 1%), sarcomatoid features, and M0 intermediate-high risk. Network meta-analyses demonstrated that pembrolizumab exhibited both DFS and OS benefit compared with placebo, sunitinib, sorafenib, and girentuximab, and only DFS benefit compared with atezolizumab and nivolumab plus ipilimumab. CONCLUSIONS: Our results suggest that post-nephrectomy RCC patients with sarcomatoid differentiation and high PD-L1 expression were more responsive to ICIs. Furthermore, pembrolizumab monotherapy exhibited superior DFS and OS results over other adjuvant therapies.


Asunto(s)
Carcinoma de Células Renales , Neoplasias Renales , Nefrectomía , Humanos , Carcinoma de Células Renales/cirugía , Carcinoma de Células Renales/tratamiento farmacológico , Carcinoma de Células Renales/patología , Neoplasias Renales/cirugía , Neoplasias Renales/patología , Neoplasias Renales/tratamiento farmacológico , Tasa de Supervivencia , Quimioterapia Adyuvante , Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Pronóstico , Recurrencia Local de Neoplasia/patología , Recurrencia Local de Neoplasia/tratamiento farmacológico , Ensayos Clínicos Controlados Aleatorios como Asunto , Terapia Combinada
3.
Adv Healthc Mater ; 13(3): e2302391, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37899694

RESUMEN

Hypoxia in chronic wounds impairs the activities of reparative cells, resulting in tissue necrosis, bacterial infections, decreased angiogenesis, and delayed wound healing. To achieve effective oxygenation therapy and restore oxygen homeostasis, oxygen-generating hydrogels based on different oxygen sources have been developed to release dissolved oxygen in the wound bed, which not only alleviate hypoxia, but also accelerate chronic wound healing. This review first discusses the vital role of oxygen and hypoxia in the wound healing process. The advancements in oxygen-generating hydrogels, which produce oxygen through the decomposition of hydrogen peroxide, metal peroxides, glucose-activated cascade reactions, and photosynthesis of algae microorganisms for chronic wound healing, are discussed and summarized. The therapeutic effects and challenges of using oxygen-generating hydrogels for the clinical treatment of chronic wounds are concluded and prospected.


Asunto(s)
Hidrogeles , Oxígeno , Humanos , Cicatrización de Heridas , Hipoxia/tratamiento farmacológico , Peróxidos
4.
Food Res Int ; 173(Pt 1): 113308, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37803613

RESUMEN

Pickled kohlrabi is a traditional and favored vegetable product in China. During pickling, the hardness, springiness, and chewiness of kohlrabi all experienced a typical change with twice "increase-decrease" trend. However, little is known about its mechanism. In this study, in situ analysis including immunofluorescence, low field nuclear magnetic, and transmission electron microscopy were used to explore the effects of cell wall pectin, water state, and cellular structure on kohlrabi texture changes during pickling. Results revealed that at the early stage, due to the rapid loss of water after three times salting, the cells shrank and the interstitial space reduced, resulting in the first increase on kohlrabi texture. Subsequently, the dehydration-rehydration caused by the first brine processing resulted in the first decrease on kohlrabi texture. Then under the action of PME enzyme, more low-esterified pectin was produced, and chelate-soluble pectin with more branched structure was further formed, leading to another elevation of the sample texture. As the pickling continued, under the combined action of PG and PME, the molecular weight of pectin was decreased and the rigidity of the cell tissue was destroyed, caused kohlrabi texture continued to decline. These researches could provide important information and guidance for better maintaining the texture of pickled vegetables during processing.


Asunto(s)
Pectinas , Agua , Pectinas/química , Agua/análisis , Polisacáridos/análisis , Pared Celular/química , Frutas/química
5.
Cell ; 186(6): 1230-1243.e14, 2023 03 16.
Artículo en Inglés | MEDLINE | ID: mdl-36931246

RESUMEN

Although Ca2+ has long been recognized as an obligatory intermediate in visual transduction, its role in plant phototransduction remains elusive. Here, we report a Ca2+ signaling that controls photoreceptor phyB nuclear translocation in etiolated seedlings during dark-to-light transition. Red light stimulates acute cytosolic Ca2+ increases via phyB, which are sensed by Ca2+-binding protein kinases, CPK6 and CPK12 (CPK6/12). Upon Ca2+ activation, CPK6/12 in turn directly interact with and phosphorylate photo-activated phyB at Ser80/Ser106 to initiate phyB nuclear import. Non-phosphorylatable mutation, phyBS80A/S106A, abolishes nuclear translocation and fails to complement phyB mutant, which is fully restored by combining phyBS80A/S106A with a nuclear localization signal. We further show that CPK6/12 function specifically in the early phyB-mediated cotyledon expansion, while Ser80/Ser106 phosphorylation generally governs phyB nuclear translocation. Our results uncover a biochemical regulatory loop centered in phyB phototransduction and provide a paradigm for linking ubiquitous Ca2+ increases to specific responses in sensory stimulus processing.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Fitocromo , Fitocromo B/genética , Fitocromo B/metabolismo , Fitocromo/genética , Fitocromo/metabolismo , Calcio/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Arabidopsis/genética , Luz , Fototransducción , Mutación
6.
Mol Cell ; 82(16): 3015-3029.e6, 2022 08 18.
Artículo en Inglés | MEDLINE | ID: mdl-35728588

RESUMEN

Light and temperature in plants are perceived by a common receptor, phytochrome B (phyB). How phyB distinguishes these signals remains elusive. Here, we report that phyB spontaneously undergoes phase separation to assemble liquid-like droplets. This capacity is driven by its C terminus through self-association, whereas the intrinsically disordered N-terminal extension (NTE) functions as a biophysical modulator of phase separation. Light exposure triggers a conformational change to subsequently alter phyB condensate assembly, while temperature sensation is directly mediated by the NTE to modulate the phase behavior of phyB droplets. Multiple signaling components are selectively incorporated into phyB droplets to form concentrated microreactors, allowing switch-like control of phyB signaling activity through phase transitions. Therefore, light and temperature cues are separately read out by phyB via allosteric changes and spontaneous phase separation, respectively. We provide a conceptual framework showing how the distinct but highly correlated physical signals are interpreted and sorted by one receptor.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Fitocromo B/genética , Fitocromo B/metabolismo , Transducción de Señal , Temperatura
7.
Sci Total Environ ; 831: 154908, 2022 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-35364172

RESUMEN

The implementation of the European Union (EU) Carbon Border Adjustment Mechanism (CBAM) will affect the cost efficiency of Chinese exporters, and few studies have considered how to deal with its impact from the carbon market perspective. Based on this, this paper constructs two price-variable resource allocation (VPRA) models to investigate China's allowance allocation strategies to mitigate the impact of the EU CBAM from a carbon market perspective. This paper takes the steel and cement industries in each province of China for example for cost efficiency assessment and carbon allowance allocation, and finds that: (1) The EU CBAM has a negative impact, and it is necessary to incorporate the CBAM into the top-level system design of allowance allocation to obtain an allowance allocation scheme that maintains the cost efficiency level of each industry. (2) A higher and more stable carbon price in China can effectively counteract the impact of the EU CBAM and ensure that the cost efficiency of each industry does not fluctuate significantly. (3) When the Chinese carbon price exceeds 60 RMB/ton, the impact of the EU CBAM on the cost efficiency of each industry will become significantly smaller. (4) Measures to reduce the number of products exported to the EU are not effective in mitigating the impact of the EU CBAM when the number of products exported to the EU exceeds a certain rate. The findings of this paper provide useful policy insights for China and other developing countries to actively address the challenges of the EU CBAM.


Asunto(s)
Carbono , Gases de Efecto Invernadero , Carbono/análisis , China , Unión Europea , Industrias
8.
Int J Biol Macromol ; 200: 449-457, 2022 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-35063483

RESUMEN

Our previous study showed that pectin de-esterified by high hydrostatic pressure assisted enzymatic method (HHP-pectin) had better Ca2+-induced gel performance and more stable emulsion than those from conventional enzymatic and alkaline methods. In this study, Ca2+-induced emulsion gels were further prepared by HHP-pectin in the presence of erythritol, and their texture properties, moisture distribution, the release of free fatty acids (FFAs) and curcumin were investigated. Results showed that gel strength, gel elasticity, and water cut-off capacity of the prepared emulsion gels significantly increased with Ca2+ concentration increasing. Compared with emulsions, HHP-pectin emulsion gels can significantly decrease FFAs and curcumin release in vitro digestion, especially for samples with better texture properties (higher Ca2+ concentration). This study indicated that Ca2+-induced HHP-pectin emulsion gels prepared with erythritol may provide a new choice for low-calorie foods preparing, and may become a potential alternative model that inhibiting FFAs release and helping fat-soluble nutrients (curcumin) deliver.


Asunto(s)
Pectinas
9.
Foods ; 10(10)2021 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-34681508

RESUMEN

Satsuma mandarin peel pectin (MPP) was extracted by citric acid and its structure and emulsifying ability were evaluated. Structural characterization, including NMR, FTIR, monosaccharide compositions demonstrated that MMP showed lower DM value and higher Mw than commercial citrus pectin (CCP). In addition, MPP exhibited significantly better emulsification performance than CCP. When MPP concentration was increased to 1%, 1.5% (10 g/L, 15 g/L) and the pH was 3 (acidic condition), a stable emulsion containing 10% oil fraction could be obtained. The particle size of the obtained emulsion was ranging from 1.0-2.3 µm, its emulsifying activity ranged from 93-100% and emulsifying stability was 94-100%. Besides, MPP can better ensure the storage stability of higher oil ratio emulsions. The results demonstrated that the stable emulsifying properties of MPP may largely depend on the lower DM value and higher Mw. MPP could be used as a novel polysaccharide emulsifier, especially under acidic conditions, providing a promising alternative for natural emulsifiers that could be used in the food industry.

10.
Int J Biol Macromol ; 159: 258-263, 2020 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-32389653

RESUMEN

Energy metabolism has been a predominant target for anti-cancer drug development. The self-assembled anti-tumor α-lactalbumin-oleic acid complex (α-LA-OA) affects the energy metabolism of tumor cells, however, the role of targeting energy metabolism in its anti-tumor mechanism still needs to be clarified. α-LA assembled with OA to form a complex with an average diameter of 144.1 ± 7.241 nm, which is 10-fold larger than α-LA alone. Furthermore, the self-assembled α-LA-OA inhibited the ATP supply from both glycolysis and oxidative phosphorylation in HepG2 cells and HepG2-bearing nude mice. The gene expression of enzymes involved in glycolysis (HK2, aldose, PKM2, LDHB) and oxidative phosphorylation (CS, ACO2, IDH2, SDHA) was inhibited. This inhibitory effect was also evident by increased phosphorylation of AMPKα. α-LA-OA also suppressed the expression of HIF-1α and increased the expression of activated caspase-3. These findings demonstrate that the anti-tumor mechanism of α-LA-OA may be related to its inhibitory effect on the ATP supply, which then activates programmed cell death pathways. This study also indicated that α-LA-OA is a potent anti-tumor agent that targets the energy metabolism of tumor cells.


Asunto(s)
Adenosina Trifosfato/biosíntesis , Ciclo del Ácido Cítrico/efectos de los fármacos , Lactalbúmina/química , Sustancias Macromoleculares/química , Sustancias Macromoleculares/farmacología , Ácido Oléico/química , Animales , Antineoplásicos/química , Antineoplásicos/farmacología , Modelos Animales de Enfermedad , Metabolismo Energético/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Glucólisis/efectos de los fármacos , Células Hep G2 , Humanos , Sustancias Macromoleculares/ultraestructura , Ratones , Ratones Desnudos , Nanopartículas/química , Fosforilación Oxidativa , Consumo de Oxígeno , Ensayos Antitumor por Modelo de Xenoinjerto
11.
Biomolecules ; 10(4)2020 03 28.
Artículo en Inglés | MEDLINE | ID: mdl-32231120

RESUMEN

Epithelial barrier dysfunction, characteristic of allergic airway disease may be, at least in part, due to the action of allergen-associated protease activities. Cockroach allergy is a major global health issue, with cockroaches containing considerable serine trypsin-like protease (TLP) activity. The present study sought to evaluate two novel protease inhibitors (PE-BBI and pLR-HL), recently isolated from amphibian skin secretions, for their potential to neutralise cockroach TLP activity and to determine any protective effect on cockroach-induced airway epithelial barrier disruption. Inhibitor potencies against the cockroach-associated activities were determined using a fluorogenic peptide substrate-based activity assay. 16HBE14o- cells (16HBE; a bronchial epithelial cell line) were treated with cockroach extract (CRE) in the presence or absence of the compounds in order to assess cell viability (RealTime Glo luminescent assay) and epithelial barrier disruption (transepithelial resistance and paracellular dextran flux). PE-BBI potently and selectively inhibited CRE TLP activity (pIC50 -8), but not host (16HBE) cell surface activity, which conferred protection of 16HBE cells from CRE-induced cell damage and barrier disruption. Novel protease inhibitor strategies such as PE-BBI may be useful for the treatment of allergic airway disease caused by cockroach proteases.


Asunto(s)
Bronquios/citología , Cucarachas/inmunología , Inhibidores de Serina Proteinasa/farmacología , Animales , Bronquios/inmunología , Línea Celular , Epitelio/efectos de los fármacos , Epitelio/inmunología , Epitelio/metabolismo
12.
Int J Biol Macromol ; 158: 401-407, 2020 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-32344084

RESUMEN

Fibroblast growth factor 19 (FGF19) acts as a novel factor in the regulation of skeletal muscle mass in animal models by regulating energy expenditure. People with obesity have a lower content of FGF19 and lose muscle mass easily. However, as the main energy metabolism organelles, the involvement of mitochondria in the protective effect of FGF19 is still unknown. In this study, the protective effects of FGF19 on palmitate-induced damages in differentiated mouse myoblast cells (C2C12) were studied, including myotube morphology, mitochondrial function and the regulation of pathways and genes. Excessive palmitate resulted in myotube atrophy and activation of the mitochondria-mediated apoptosis pathway in C2C12 cells. Palmitate also inhibited glucose uptake and induced insulin resistance. FGF19 addition during the differentiation of C2C12 cells, returned the palmitate-induced mitochondrial respiration and apoptosis to the control levels and improved the insulin sensitivity. The palmitate-induced upregulation of genes involved in ß-oxidation (PPARß/δ, PPARγ, UCP-1, MCAD) and the downregulation of genes related to myotube atrophy (PPARα, PGC-1α and PGC-1ß) were also alleviated by FGF19. In summary, FGF19 prevented excessive palmitate-induced dysfunction of C2C12 cells by protecting mitochondrial overload and apoptosis and maintaining normal insulin signaling.

13.
Dev Cell ; 51(1): 78-88.e3, 2019 10 07.
Artículo en Inglés | MEDLINE | ID: mdl-31495692

RESUMEN

Apical hook curvature is crucial for buried seedling survival and a superb model for dissecting differential cell growth. HOOKLESS1 (HLS1) is essential for apical hook formation, acting as a hub integrating various external and internal signals. However, its functional mechanism remains unclear. Here, we demonstrate that HLS1 protein is present as an oligomer in the nucleus of dark-grown seedlings. Oligomerization is required for HLS1 activation, as the mutated HLS1 protein abolishing self-association exists as nonfunctional monomers. Upon light exposure, photoreceptor phyB translocates into the nucleus and interacts with HLS1, disrupting the self-association and oligomerization of HLS1 to initiate hook unfolding. Remarkably, genetic expression of nuclear-localized phyB is sufficient to inactivate HLS1, resulting in compromised hook curvature in etiolated seedlings. Together, we conclude that HLS1 protein is active as oligomeric form in darkness and achieves allosteric photo-deactivation upon light, providing intriguing mechanistic insight into the molecular switch for developmental transition.


Asunto(s)
Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/fisiología , Regulación de la Expresión Génica de las Plantas , Luz , Sitio Alostérico , Arabidopsis/genética , Arabidopsis/fisiología , Diferenciación Celular , Núcleo Celular/fisiología , Etilenos/metabolismo , Células HEK293 , Humanos , Morfogénesis , Mutación , Fenotipo , Fitocromo B/fisiología , Unión Proteica , Transporte de Proteínas , Plantones/fisiología , Transducción de Señal
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