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1.
Chaos ; 34(2)2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38341764

RESUMEN

The emergence of the evolutionary game on complex networks provides a fresh framework for studying cooperation behavior between complex populations. Numerous recent progress has been achieved in studying asymmetric games. However, there is still a substantial need to address how to flexibly express the individual asymmetric nature. In this paper, we employ mutual cognition among individuals to elucidate the asymmetry inherent in their interactions. Cognition arises from individuals' subjective assessments and significantly influences their decision-making processes. In social networks, mutual cognition among individuals is a persistent phenomenon and frequently displays heterogeneity as the influence of their interactions. This unequal cognitive dynamic will, in turn, influence the interactions, culminating in asymmetric outcomes. To better illustrate the inter-individual cognition in asymmetric snowdrift games, the concept of favor value is introduced here. On this basis, the evolution of cognition and its relationship with asymmetry degree are defined. In our simulation, we investigate how game cost and the intensity of individual cognitive changes impact the cooperation frequency. Furthermore, the temporal evolution of individual cognition and its variation under different parameters was also examined. The simulation results reveal that the emergence of heterogeneous cognition effectively addresses social dilemmas, with asymmetric interactions among individuals enhancing the propensity for cooperative choices. It is noteworthy that distinctions exist in the rules governing cooperation and cognitive evolution between regular networks and Watts-Strogatz small-world networks. In light of this, we deduce the relationship between cognition evolution and cooperative behavior in co-evolution and explore potential factors influencing cooperation within the system.


Asunto(s)
Cognición , Teoría del Juego , Humanos , Simulación por Computador , Conducta Cooperativa , Red Social , Evolución Biológica
2.
Luminescence ; 31(2): 335-340, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26179104

RESUMEN

Chrysoidine is widely used in industry as a type of azo dye, and is sometimes used illegally as a food additive despite its potential toxicity. Human serum albumin (HSA) is one of the most important proteins in blood plasma and possesses major physiological functions. In the present study, the conformational and functional effects of chrysoidine on HSA were investigated by isothermal titration calorimetry (ITC), multiple spectroscopic methods, a molecular docking study and an esterase activity assay. Based on the ITC results, the binding stoichiometry of chrysoidine to HSA was estimated to be 1.5:1, and was a spontaneous process via a single hydrogen bond. The binding of chrysoidine to HSA induced dynamic quenching in fluorescence, and changes in secondary structure and in the microenvironment of the Trp-214 residue. In addition, the hydrogen bond (1.80 Å) formed between the chrysoidine molecule and the Gln-211 residue. The esterase activity of HSA decreased following the addition chrysoidine due to the change in protein structure. This study details the direct interaction between chrysoidine and HSA at the molecular level and the mechanism for toxicity as a result of the functional changes induced by HSA structural variation upon binding to chrysoidine in vitro. This study provides useful information towards detailing the transportation mechanism and toxicity of chrysoidine in vivo.


Asunto(s)
Calorimetría , Albúmina Sérica/metabolismo , p-Aminoazobenceno/análogos & derivados , Esterasas/química , Esterasas/metabolismo , Fluorescencia , Humanos , Enlace de Hidrógeno , Simulación del Acoplamiento Molecular , Estructura Molecular , Conformación Proteica/efectos de los fármacos , Albúmina Sérica/química , Espectrometría de Fluorescencia , Espectrofotometría Ultravioleta , p-Aminoazobenceno/química , p-Aminoazobenceno/toxicidad
3.
Oncol Lett ; 27(2): 72, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38192669

RESUMEN

Metastatic ependymoma of the gallbladder is an exceptionally rare condition that remains relatively unreported in the scientific literature. The present study described a case involving a 42-year-old female patient who underwent right frontal lobe surgery for ependymoma in 2017 and subsequently received adjuvant chemotherapy. The histological examination of the surgical specimen confirmed the presence of ependymoma metastasis in the gallbladder. The presentation and outcome of this patient with regard to metastatic ependymoma in the gallbladder were evaluated. During a follow-up period of 10 months, the patient received targeted treatment following the surgery. Presently, the patient has developed lung and bone metastases. In the present report, the treatment and diagnostic approach utilized in this unique case were outlined with the aim of providing valuable insight for future clinical management and enhancing clinicians' understanding of the disease.

4.
Zhongguo Zhong Yao Za Zhi ; 38(2): 193-8, 2013 Jan.
Artículo en Zh | MEDLINE | ID: mdl-23672040

RESUMEN

OBJECTIVE: To compare the antioxidant active components from two species of chamomile-matricaria and Roman chamomile produced in Xinjiang. METHOD: The TLC-bioautography was used, with 1,1-Diphenyl-2-picrylhydrazyl (DPPH) radical as the experimental model. The peak areas of various antioxidant components were obtained by TLC-scanning for analyzing antioxidant active components contained in volatile oil extracts and flavone extracts from the two species of chamomiles. The total peak area was taken as the indicator for comparing the antioxidant capacities of the two types of extracts, and comparing them with the total antioxidant activity of flavone extracts of the two species of chamomiles. RESULTS: According to the result of TLC-bioautography in volatile oil extracts from the two species of chamomiles, volatile oil extracts from chamomile showed four white antioxidant spots, including en-yne-dicycloether, and volatile oil extracts from Roman chamomile showed only one white antioxidant spot. The TLC-scanning result showed that the peak area of antioxidant spots of volatile oil extracts from chamomile was significantly larger than that of volatile oil extracts from Roman chamomile. According to the test on the antioxidant activity of the two species of chamomiles with ultraviolet-visible spectrophotometry, the concentration of chamomile after scavenging 50% of DPPH radicals was 0.66 g x L(-1), whereas the figure for Roman chamomile was 0.33 g x L(-1). According to the result of TLC-bioautography in flavone extracts from the two species of chamomiles, flavone extracts from chamomile showed seven yellowish antioxidant spots, including apigenin and apigenin-7-glucoside, and flavone extracts of Roman chamomile showed eight yellowish antioxidant spots, including apigenin and apigenin-7-glucoside. The TLC-scanning results showed that the peak area of antioxidant spots of flavone extracts from Roman chamomile was significantly larger than that of flavone extracts from chamomile. CONCLUSION: Volatile oil extracts from the two species of chamomiles have significant difference in the antioxidant activity in TLC-bioautography. Specifically, the antioxidant activity of volatile oil extracts from chamomile is stronger than volatile oil extracts from Roman chamomile; the known antioxidant active components in volatile oil extracts from chamomile is en-yne-dicycloether, while all of the other three antioxidant active components as well as antioxidant active components in volatile oil extracts from Roman chamomile are unknown components and remain to be further determined. Considering the significant difference in the number of antioxidant active spots in volatile oil extracts from the two species of chamomiles, the result can be applied to distinguish the two species of chamomiles. The antioxidant activity determination result for flavone extracts from two species of chamomiles was consistent with the result of TLC-bioautography, showing that flavone extracts from chamomile and Roman chamomile are more antioxidant active, while that of Roman chamomile is stronger than chamomile. Flavone extracts from both of the two species of chamomiles contain apigenin and pigenin-7-glucoside, which are known, while all of the other five antioxidant active components contained in flavone extracts from chamomile and the other six antioxidant active components contained in flavone extracts from Roman chamomile are unknown and remain to be further identified. The method lays a foundation for further identification of antioxidant active components contained in chamomile.


Asunto(s)
Antioxidantes/química , Chamaemelum/química , Cromatografía en Capa Delgada/métodos , Flavonas/química , Matricaria/química , Aceites Volátiles/química , Antioxidantes/aislamiento & purificación , Apigenina/química , Apigenina/aislamiento & purificación , Compuestos de Bifenilo/metabolismo , Flavonas/aislamiento & purificación , Depuradores de Radicales Libres/química , Depuradores de Radicales Libres/aislamiento & purificación , Glucósidos/química , Glucósidos/aislamiento & purificación , Aceites Volátiles/aislamiento & purificación , Picratos/metabolismo , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Aceites de Plantas/química , Aceites de Plantas/aislamiento & purificación
5.
Environ Sci Pollut Res Int ; 30(39): 90799-90813, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37460893

RESUMEN

Although heterogeneous Fenton catalysis has captured increasing attention compared to its homogeneous counterpart, it still confronts some inherent drawbacks in use, such as the dilemma in solid-liquid separation and greater mass transfer resistance. Driven by the acoustic cavitation effect, herein, a sono-enhanced heterogeneous Fenton catalysis process was built to overcome the above two shortcomings, by rapidly synthesizing magnetic Fenton-like catalysts and accelerating electron transfer during the catalytic reaction. The results show that, compared to the traditional chemical coprecipitation method, Fe3O4 with smaller particle size and better crystallinity grew on the surface of halloysite nanotubes (HNTs) by using the sonochemical strategy, leading to displaying the higher catalytic activity toward the degradation of methylene blue (MB, improved by ~2.5 times). In parallel, more •OH and •O2- were produced after the ultrasound was further introduced to the routine Fenton-like catalysis system, thus highly accelerating the removal of MB (improved by ~50%). Besides, benefiting from the robust chemical integration of Fe3O4 and HNTs, Fe3O4@HNTs-S had a lower iron ion leaching in use, showing superior catalytic stability. The speed, simplicity, and generality, together with the enhanced mass transfer rate, make the use of ultrasound an enabling methodology to improve the heterogeneous Fenton catalysis.


Asunto(s)
Nanotubos , Arcilla , Radicales Libres , Catálisis , Fenómenos Magnéticos , Peróxido de Hidrógeno
6.
Materials (Basel) ; 16(11)2023 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-37297082

RESUMEN

Porous LaFeO3 powders were produced by high-temperature calcination of LaFeO3 precursors obtained by hydrothermal treatment of corresponding nitrates in the presence of citric acid. Four LaFeO3 powders calcinated at different temperatures were mixed with appropriate amounts of kaolinite, carboxymethyl cellulose, glycerol and active carbon for the preparation of monolithic LaFeO3 by extrusion. Porous LaFeO3 powders were characterized using powder X-ray diffraction, scanning electron microscopy, nitrogen absorption/desorption and X-ray photoelectron spectroscopy. Among the four monolithic LaFeO3 catalysts, the catalyst calcinated at 700 °C showed the best catalytic activity for the catalytic oxidation of toluene at 36,000 mL/(g∙h), and the corresponding T10%, T50% and T90% was 76 °C, 253 °C and 420 °C, respectively. The catalytic performance is attributed to the larger specific surface area (23.41 m2/g), higher surface adsorption of oxygen concentration and larger Fe2+/Fe3+ ratio associated with LaFeO3 calcined at 700 °C.

7.
J Thromb Haemost ; 21(2): 344-358, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36700501

RESUMEN

BACKGROUND: Platelet shedding from mature megakaryocytes (MKs) in thrombopoiesis is the critical step for elevating circulating platelets fast and efficiently, however, the underlying mechanism is still not well-illustrated, and the therapeutic targets and candidates are even less. OBJECTIVES: In order to investigate the mechanisms for platelet shedding after vasopressin treatment and find new therapeutic targets for thrombocytopenia. METHODS: Platelet production was evaluated both in vivo and in vitro after arginine vasopressin (AVP) administration. The underlying biological mechanism of AVP-triggered thrombopoiesis were then investigated by a series of molecular and bioinformatics techniques. RESULTS: it is observed that proplatelet formation and platelet shedding in the final stages of thrombopoiesis promoted by AVP, an endogenous hormone, can quickly increases peripheral platelets. This rapid elevation is thus able to speed up platelet recovery after radiation as expected. The mechanism analysis reveal that proplatelet formation and platelet release from mature MKs facilitated by AVP is mainly mediated by Akt-regulated mitochondrial metabolism. In particular, phosphorylated Akt regulates mitochondrial metabolism through driving the association of hexokinase-2 with mitochondrial voltage dependent anion channel-1 in AVP-mediated thrombopoiesis. Further studies suggest that this interaction is stabilized by IκBα, the expression of which is controlled by insulin-regulated membrane aminopeptidase. CONCLUSION: these data demonstrate that phosphorylated Akt-mediated mitochondrial metabolism regulates platelet shedding from MKs in response to AVP, which will provide new therapeutic targets and further drug discovery clues for thrombocytopenia treatment.


Asunto(s)
Proteínas Proto-Oncogénicas c-akt , Trombocitopenia , Humanos , Proteínas Proto-Oncogénicas c-akt/metabolismo , Plaquetas/metabolismo , Megacariocitos/metabolismo , Trombopoyesis/fisiología , Trombocitopenia/metabolismo , Vasopresinas/farmacología , Vasopresinas/metabolismo
8.
Dalton Trans ; 51(42): 16325-16335, 2022 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-36222463

RESUMEN

Near-infrared (NIR) emitting LED devices have broad applications. Using a visible light LED chip to excite Cr3+-activated phosphors to obtain NIR light has attracted extensive attention. In this study, a near-infrared luminescent material, Cr3+-doped Sc1-xTaO4, was synthesized by the element substitution method. It demonstrated a long emission wavelength (940 nm) and wide full width at half maximum (FWHM) (186 nm). The morphology, structure and photoluminescence of the samples were investigated using X-ray powder diffraction (XRD), scanning electron microscopy (SEM) and photoluminescence (PL) spectroscopy techniques. Moreover, the relationship between the NIR emission properties of Cr3+ and the substituted ions in the crystal matrix was studied. Based on this material, we fabricated near-infrared LED devices, which exhibited good near-infrared luminescence properties.

9.
Sci Total Environ ; 709: 136002, 2020 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-31905586

RESUMEN

Modified anion exchange resin (EDE-D301) was synthesized by mixing monomers: epichlorohydrin (ECH), dimethylamine (DMA), ethylenediamine (EDA) with the weakly alkaline anion exchange resin D301 through in-situ polymerization method. Adsorption performance of EDE-D301 for removing Cr(VI) contaminants was investigated in batch and column systems. Physicochemical properties of the anion exchange resins were characterized to determine the adsorption mechanism and regeneration ability. Characteristic results revealed that EDE-D301 showed enhanced surface area, positive charge and contents of N and Cl elements, indicating that the modifying reagents of monomers were successfully polymerized in the resin. The experimental adsorption data fitted well to the pseudo-second-order kinetic model and the Langmuir isotherm model. The fixed-bed experiments showed that the exhaustion time increased with increasing the bed depth, and decreased with increasing the flowrate and influent concentration. Adsorption capacity for Cr(VI) onto EDE-D301 was determined at a maximum level of 298 mg·g-1, and remained at 93% after four consecutive cycles. FTIR and XPS analysis indicated that the ion exchange and complexation were responsible for the Cr(VI) adsorption.

10.
Chemosphere ; 196: 418-428, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29324383

RESUMEN

Cyanobacterial bloom causes the release of algal organic matter (AOM), which inevitably affects the treatment processes of natural organic matter (NOM). This study works on treating micro-polluted surface water (SW) by emerging coagulant, namely titanium sulfate (Ti(SO4)2), followed by Low Pressure Ultrafiltration (LPUF) technology. In particular, we explored the respective influence of extracellular organic matter (EOM) and intracellular organic matter (IOM) on synergetic EOM-NOM/IOM-NOM removal, functional mechanisms and subsequent filtration performance. Results show that the IOM inclusion in surface water body facilitated synergic IOM-NOM composite pollutants removal by Ti(SO4)2, wherein loosely-aggregated flocs were produced, resulting in floc cake layer with rich porosity and permeability during LPUF. On the contrary, the surface water invaded by EOM pollutants increased Ti(SO4)2 coagulation burden, with substantially deteriorated both UV254-represented and dissolved organic matter (DOC) removal. Corresponded with the weak Ti(SO4)2 coagulation for EOM-NOM removal was the resultant serious membrane fouling during LPUF procedure, wherein dense cake layer was formed due to the compact structure of flocs. Although the IOM enhanced NOM removal with reduced Ti(SO4)2 dose and yielded mitigated membrane fouling, larger percentage of irreversible fouling was seen than NOM and EOM-NOM cases, which was most likely due to the substances with small molecular weight, such as microcystin, adhering in membrane pores. This research would provide theoretical basis for dose selection and process design during AOM-NOM water treatment.


Asunto(s)
Microcystis/metabolismo , Ultrafiltración/métodos , Purificación del Agua/métodos , Membranas Artificiales , Permeabilidad , Titanio
11.
Mar Pollut Bull ; 98(1-2): 137-47, 2015 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-26277602

RESUMEN

Parameter optimization is important for developing a water quality dynamic model. In this study, we applied data-driven method to select and optimize parameters for a complex three-dimensional water quality model. First, a data-driven model was developed to train the response relationship between phytoplankton and environmental factors based on the measured data. Second, an eight-variable water quality dynamic model was established and coupled to a physical model. Parameter sensitivity analysis was investigated by changing parameter values individually in an assigned range. The above results served as guidelines for the control parameter selection and the simulated result verification. Finally, using the data-driven model to approximate the computational water quality model, we employed the Particle Swarm Optimization (PSO) algorithm to optimize the control parameters. The optimization routines and results were analyzed and discussed based on the establishment of the water quality model in Xiangshan Bay (XSB).


Asunto(s)
Modelos Teóricos , Calidad del Agua , Algoritmos , China , Eutrofización , Fitoplancton
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