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1.
Angew Chem Int Ed Engl ; 63(21): e202402840, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38509835

RESUMO

The doped organic hole transport layer (HTL) is crucial for achieving high-efficiency perovskite solar cells (PSCs). However, the traditional doping strategy undergoes a time-consuming and environment-dependent oxidation process, which hinders the technology upgrades and commercialization of PSCs. Here, we reported a new strategy by introducing a cascade reaction in traditional doped Spiro-OMeTAD, which can simultaneously achieve rapid oxidation and overcome the erosion of perovskite by 4-tert-butylpyridine (tBP) in organic HTL. The ideal dopant iodobenzene diacetate was utilized as the initiator that can react with Spiro to generate Spiro⋅+ radicals quickly and efficiently without the participation of ambient air, with the byproduct of iodobenzene (DB). Then, the DB can coordinate with tBP through a halogen bond to form a tBP-DB complex, minimizing the sustained erosion from tBP to perovskite. Based on the above cascade reaction, the resulting Spiro-based PSCs have a champion PCE of 25.76 % (certificated of 25.38 %). This new oxidation process of HTL is less environment-dependent and produces PSCs with higher reproducibility. Moreover, the PTAA-based PSCs obtain a PCE of 23.76 %, demonstrating the excellent applicability of this doping strategy on organic HTL.

2.
Neurochem Int ; 170: 105603, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37633650

RESUMO

Intracerebral hemorrhage (ICH), which has high mortality and disability rate is associated with microglial pyroptosis and neuroinflammation, and the effective treatment methods are limited Epigallocatechin-3-gallate (EGCG) has been found to play a cytoprotective role by regulating the anti-inflammatory response to pyroptosis in other systemic diseases. However, the role of EGCG in microglial pyroptosis and neuroinflammation after ICH remains unclear. In this study, we investigated the effects of EGCG pretreatment on neuroinflammation-mediated neuronal pyroptosis and the underlying neuroprotective mechanisms in experimental ICH. EGCG pretreatment was found to remarkably improved neurobehavioral performance, and decreased the hematoma volume and cerebral edema in mice. We found that EGCG pretreatment attenuated the release of hemin-induced inflammatory cytokines (IL-1ß, IL-18, and TNF-α). EGCG significantly upregulated the expression of heme oxygenase-1 (HO-1), and downregulated the levels of pyroptotic molecules and inflammatory cytokines including Caspase-1, GSDMD, NLRP3, mature IL-1ß, and IL-18. EGCG pretreatment also decreased the number of Caspase-1-positive microglia and GSDMD along with NLRP3-positive microglia after ICH. Conversely, an HO-1-specific inhibitor (ZnPP), significantly inhibited the anti-pyroptosis and anti-neuroinflammation effects of EGCG. Therefore, EGCG pretreatment alleviated microglial pyroptosis and neuroinflammation, at least in part through the Caspase-1/GSDMD/NLRP3 pathway by upregulating HO-1 expression after ICH. In addition, EGCG pretreatment promoted the polarization of microglia from the M1 phenotype to M2 phenotype after ICH. The results suggest that EGCG is a potential agent to attenuate neuroinflammation via its anti-pyroptosis effect after ICH.


Assuntos
Hemorragia Cerebral , Heme Oxigenase-1 , Microglia , Doenças Neuroinflamatórias , Fármacos Neuroprotetores , Animais , Camundongos , Caspases/metabolismo , Caspases/farmacologia , Hemorragia Cerebral/tratamento farmacológico , Hemorragia Cerebral/genética , Hemorragia Cerebral/metabolismo , Citocinas/metabolismo , Heme Oxigenase-1/genética , Heme Oxigenase-1/metabolismo , Interleucina-18/metabolismo , Interleucina-18/farmacologia , Microglia/efeitos dos fármacos , Microglia/metabolismo , Doenças Neuroinflamatórias/tratamento farmacológico , Doenças Neuroinflamatórias/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Piroptose/efeitos dos fármacos , Piroptose/genética , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico
4.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-802189

RESUMO

Abri Herba,a kind of plant of Leguminosae family,is widely distributed in Guangdong and Guangxi,with rich resources.With a long medication history in China,its whole-plant, apart from plant seeds have been used as medicine, with the effects in removing dampness and removing jaundice, clearing heat and detoxifying,and clearing the liver and relieving pain. By accessing CNKI, Wanfang date,VIP Web, ScienceDirect,FMRS, Pubmed and multiple domestic and foreign databases,recent literatures on chemical constituents and pharmacological action and clinical trials of Abri Herba were collected and summarized in a review.According to a great quantity of relevant domestic and foreign literatures.Abri herba contains abundant chemical constituents, such as betulinic acid and other triterpenoids, catechin and other flavonoids,abrine and other alkaloids, chrysophanol and other anthraquinones, as well as inorganic elements.Abri Herba has a wide range of pharmacological effects due to rich material basis. Abri Herba, as a folk traditional herb, is used to treat jaundice with damp-heat pathogen, distending pain in the stomach, acute mastitisand gall, steatosis hepatis, hepatitis and internal traumatic injury. It also has many other effects in resisting tumor,oxidation,bacteria,virus and inflammation, relieving pain, promoting wound healing and regulating immunity.At present, there is single herb or traditional Chinese medicine compounds of Abri Herba in clinic, and the latter is the majority. Abri Herba can play a better pesticide effect by combining with traditional Chinese medicine. With a wide range of pharmacological effects,cheap price and easy cultivation. Abri Herba has high economic and social benefits, great potential for development and broad market prospects.Based on domestic and foreign studies on Abri Herba in past 30 years, the recent progress in the studies on chemical constituents,biological activities and clinical applications of this plant was reviewed in this paper, in the expectation of providing reference for further development and comprehensive utilization of Abri Herba medicinal resources.

5.
Chaos ; 28(5): 051102, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29857681

RESUMO

Dealing with the protection of critical infrastructures, many game-theoretic methods have been developed to study the strategic interactions between defenders and attackers. However, most game models ignore the interrelationship between different components within a certain system. In this paper, we propose a simultaneous-move attacker-defender game model, which is a two-player zero-sum static game with complete information. The strategies and payoffs of this game are defined on the basis of the topology structure of the infrastructure system, which is represented by a complex network. Due to the complexity of strategies, the attack and defense strategies are confined by two typical strategies, namely, targeted strategy and random strategy. The simulation results indicate that in a scale-free network, the attacker virtually always attacks randomly in the Nash equilibrium. With a small cost-sensitive parameter, representing the degree to which costs increase with the importance of a target, the defender protects the hub targets with large degrees preferentially. When the cost-sensitive parameter exceeds a threshold, the defender switches to protecting nodes randomly. Our work provides a new theoretical framework to analyze the confrontations between the attacker and the defender on critical infrastructures and deserves further study.

6.
Sci Rep ; 7(1): 7559, 2017 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-28790416

RESUMO

Many real-world systems can be described by scale-free networks with power-law degree distributions. Scale-free networks show a "robust yet fragile" feature due to their heterogeneous degree distributions. We propose to enhance the structural robustness of scale-free networks against intentional attacks by changing the displayed network structure information rather than modifying the network structure itself. We first introduce a simple mathematical model for attack information and investigate the impact of attack information on the structural robustness of scale-free networks. Both analytical and numerical results show that decreasing slightly the attack information perfection by information disturbance can dramatically enhance the structural robustness of scale-free networks. Then we propose an optimization model of disturbance strategies in which the cost constraint is considered. We analyze the optimal disturbance strategies and show an interesting but counterintuitive finding that disturbing "poor nodes" with low degrees preferentially is more effective than disturbing "rich nodes" with high degrees preferentially. We demonstrate the efficiency of our method by comparison with edge addition method and validate the feasibility of our method in two real-world critical infrastructure networks.

7.
Sci Rep ; 6: 37317, 2016 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-27853301

RESUMO

Robustness and small-world effect are two crucial structural features of complex networks and have attracted increasing attention. However, little is known about the relation between them. Here we demonstrate that, there is a conflicting relation between robustness and small-world effect for a given degree sequence. We suggest that the robustness-oriented optimization will weaken the small-world effect and vice versa. Then, we propose a multi-objective trade-off optimization model and develop a heuristic algorithm to obtain the optimal trade-off topology for robustness and small-world effect. We show that the optimal network topology exhibits a pronounced core-periphery structure and investigate the structural properties of the optimized networks in detail.

8.
Sci Rep ; 6: 22916, 2016 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-26960247

RESUMO

The study of network disintegration has attracted much attention due to its wide applications, including suppressing the epidemic spreading, destabilizing terrorist network, preventing financial contagion, controlling the rumor diffusion and perturbing cancer networks. The crux of this matter is to find the critical nodes whose removal will lead to network collapse. This paper studies the disintegration of networks with incomplete link information. An effective method is proposed to find the critical nodes by the assistance of link prediction techniques. Extensive experiments in both synthetic and real networks suggest that, by using link prediction method to recover partial missing links in advance, the method can largely improve the network disintegration performance. Besides, to our surprise, we find that when the size of missing information is relatively small, our method even outperforms than the results based on complete information. We refer to this phenomenon as the "comic effect" of link prediction, which means that the network is reshaped through the addition of some links that identified by link prediction algorithms, and the reshaped network is like an exaggerated but characteristic comic of the original one, where the important parts are emphasized.


Assuntos
Algoritmos , Redes Comunitárias , Epidemias/estatística & dados numéricos , Administração Financeira/estatística & dados numéricos , Humanos , Terrorismo/estatística & dados numéricos
9.
Brain Res ; 1325: 53-62, 2010 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-20156422

RESUMO

Sweet taste usually signifies the presence of caloric food. It is commonly accepted that a close association exists among sweet taste perception, preference, and nutritional status. However, the mechanisms involved remain unknown. To investigate whether nutritional status affects the preference for palatable solutions and alters sweet taste receptor gene expression in rats, we measured saccharin intake and preference using a two-bottle preference test, and changes in body weight, plasma leptin levels, and gene expression for the sweet taste receptor in taste buds in high-fat diet-induced obese rats and chronically diet-restricted rats. We found that the consumption and preference ratios for 0.01 and 0.04 M saccharin were significantly lower in the high-fat diet-induced obese rats than in the normal diet rats, while the serum leptin levels were markedly increased in obese rats. Consistent with the changes in saccharin intake, the gene expression level of the sweet taste receptor T1R3 was significantly decreased in the high-fat diet-induced obese rats compared with the control rats. By contrast, the chronically diet-restricted rats showed remarkably enhanced consumption and preference for 0.04 M saccharin. The serum leptin concentration was decreased, and the gene expression of the leptin receptor was markedly increased in the taste buds. In conclusion, our results suggest that nutritional status alters saccharin preference and the expression of T1R3 in taste buds. These processes may be involved in the mechanisms underlying the modulation of peripheral sweet taste sensitivity, in which leptin plays a role.


Assuntos
Dieta , Comportamento Alimentar/fisiologia , Preferências Alimentares/fisiologia , Receptores Acoplados a Proteínas G/metabolismo , Sacarina , Papilas Gustativas/fisiologia , Animais , Peso Corporal/fisiologia , Gorduras na Dieta/administração & dosagem , Privação de Alimentos/fisiologia , Expressão Gênica , Leptina/sangue , Masculino , Obesidade/sangue , Obesidade/fisiopatologia , RNA Mensageiro/metabolismo , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Receptores Acoplados a Proteínas G/genética , Papilas Gustativas/fisiopatologia
10.
Zhong Yao Cai ; 29(8): 767-9, 2006 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-17076235

RESUMO

OBJECTIVE: In order to make use of the resources of total flavanone in pericarp of longan. METHODS: The flavonids were extracted with ethanol. Used spectrophotometry to check the flavanone. RESULTS: The total flavanone in the pericarp was 1.101 mg/ml and the rate of recovery was 99.98%. CONCLUSION: The extraction and purifying methods in this experiment can get the outcome and the purity of the flavanone very high. This method is a purely physical process and has not any pollution. It is an ideal way to extract the flavanone of longan skin.


Assuntos
Flavanonas/isolamento & purificação , Plantas Medicinais/química , Sapindaceae/química , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/isolamento & purificação , Etanol , Flavanonas/análise , Frutas/química , Temperatura Alta , Casca de Planta/química , Espectrofotometria Ultravioleta
11.
Yi Chuan ; 28(9): 1112-6, 2006 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-16963421

RESUMO

CEL I, extracted from celery, is the first known eukaryotic nuclease that cleaves DNA with high specificity at sites of base-substitution mismatch and DNA distortion. It is a key enzyme for TILLING research. Here we reported a crude extraction method and activity assay of CEL I. Incision at mismatches of single nucleotide suggested that CEL I can effectively detect DNA at G-->A base substitution and the result can be obtained from an ABI377 Sequencer. Therefore, the extracted enzyme can be used in TILLING.


Assuntos
Apium/enzimologia , Carboxilesterase/isolamento & purificação , Carboxilesterase/metabolismo , Extratos Vegetais , Pareamento Incorreto de Bases , Desoxirribonucleotídeos/genética , Desoxirribonucleotídeos/metabolismo , Eletroforese em Gel de Poliacrilamida , Genoma de Planta , Mutação Puntual , Especificidade por Substrato
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