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1.
Cell ; 149(5): 1073-83, 2012 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-22632971

RESUMEN

How complex signaling networks shape highly coordinated, multistep cellular responses is poorly understood. Here, we made use of a network-perturbation approach to investigate causal influences, or "crosstalk," among signaling modules involved in the cytoskeletal response of neutrophils to chemoattractant. We quantified the intensity and polarity of cytoskeletal marker proteins over time to characterize stereotyped cellular responses. Analyzing the effects of network disruptions revealed that, not only does crosstalk evolve rapidly during polarization, but also that intensity and polarity responses are influenced by different patterns of crosstalk. Interestingly, persistent crosstalk is arranged in a surprisingly simple circuit: a linear cascade from front to back to microtubules influences intensities, and a feed-forward network in the reverse direction influences polarity. Our approach provided a rational strategy for decomposing a complex, dynamically evolving signaling system and revealed evolving paths of causal influence that shape the neutrophil polarization response.


Asunto(s)
Polaridad Celular , Microtúbulos/metabolismo , Neutrófilos/citología , Neutrófilos/metabolismo , Transducción de Señal , Algoritmos , Humanos , Cinética , Fenotipo
2.
Inorg Chem ; 2024 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-38994650

RESUMEN

Electrochemical nitrate reduction (NO3RR) to ammonia production is regarded as one of the potential alternatives for replacing the Haber-Bosch technology for realizing artificial ammonia synthesis. In this study, a CuCo2O4/CuO-Ar heterostructure in the shape of dandelion nanospheres formed by nanoarrays has been successfully constructed, demonstrating excellent NO3RR performance. Experimental results indicate that Ar plasma etching of CuCo2O4/CuO-Ar significantly increases the content of oxygen vacancies compared to the sample of CuCo2O4/CuO-Air etched by air plasma, resulting in improved NO3RR performance. Density functional theory calculations further confirm that the existence of more oxygen vacancies effectively decreases the energy barrier of nitrate adsorption, which is due to the generation of more oxygen vacancies facilitating nitrate adsorption and weakening the N-O bonds of nitrate after plasma treatment. As a result, CuCo2O4/CuO-Ar exhibits a high NH3 yield of 0.55 mmol h-1 cm-2 and a Faraday efficiency of 95.07% at the optimal potential of -0.9 V (vs RHE) in a neutral medium. Importantly, CuCo2O4/CuO-Ar also showcases excellent electrocatalytic stability. This study presents new views on the design and structure regulation of NO3RR electrocatalysts and their potential applications in the future.

3.
Med Sci Monit ; 30: e944662, 2024 03 29.
Artículo en Inglés | MEDLINE | ID: mdl-38551033

RESUMEN

The Editors of Medical Science Monitor wish to inform you that the above manuscript has been retracted from publication due to concerns with the credibility and originality of the study, the manuscript content, and the Figure images. Reference: Wei Wei, Yanqin Wang, Xiaoming Yu, Lan Ye, Yuhua Jiang, Yufeng Cheng. Expression of TP53, BCL-2, and VEGFA Genes in Esophagus Carcinoma and its Biological Significance. Med Sci Monit, 2015; 21: 3016-3022. DOI: 10.12659/MSM.894640.

4.
Small ; 19(36): e2302132, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37127874

RESUMEN

Ultrathin 2D porous carbon-based materials offer numerous fascinating electrical, catalytic, and mechanical properties, which hold great promise in various applications. However, it remains a formidable challenge to fabricate these materials with tunable morphology and composition by a simple synthesis strategy. Here, a facile one-step self-flowering method without purification and harsh conditions is reported for large-scale fabrication of high-quality ultrathin (≈1.5 nm) N-doped porous carbon nanosheets (NPC) and their composites. It is demonstrated that the layered tannic/oxamide (TA/oxamide) hybrid is spontaneously blown, exfoliated, bloomed, in situ pore-formed, and aromatized during pyrolysis to form flower-like aggregated NPC. This universal one-step self-flowering system is compatible with various precursors to construct multiscale NPC-based composites (Ru@NPC, ZnO@NPC, MoS2 @NPC, Co@NPC, rGO@NPC, etc.). Notably, the programmable architecture enables NPC-based materials with excellent multifunctional performances, such as microwave absorption and hydrogen evolution. This work provides a facile, universal, scalable, and eco-friendly avenue to fabricate functional ultrathin porous carbon-based materials with programmability.

5.
Small ; 19(48): e2304612, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37533398

RESUMEN

Selective hydrogenolysis of glycerol to 1,3-propanediol (1,3-PDO) is recognized as one of the most promising reactions for the valorization of biomass. Precise activation of C─O bonds of glycerol molecule is the key step to realize the high yield of catalytic conversion. Here, a Pt-loaded Nb-W composite oxides with crystallographic shear phase for the precise activation and cleavage of secondary C─O (C(2)─O) bonds are first reported. The developed Nb14 W3 O44 with uniform structure possesses arrays of W-O-Nb active sites that totally distinct from individual WOx or NbOx species, which is superior to the adsorption and activation of C(2)─O bonds. The Nb14 W3 O44 support with rich reversible redox couples also promotes the electron feedback ability of Pt and enhances its interaction with Pt nanoparticles, resulting in high activity for H2 dissociation and hydrogenation. All these favorable factors confer the Pt/Nb14 W3 O44 excellent performance for selective hydrogenolysis of glycerol to 1,3-PDO with the yield of 75.2% exceeding the record of 66%, paying the way for the commercial development of biomass conversion. The reported catalysts or approach can also be adopted to create a family of Nb-W metal composite oxides for other catalytic reactions requiring selective C─O bond activation and cleavage.

6.
Acc Chem Res ; 55(9): 1301-1312, 2022 05 03.
Artículo en Inglés | MEDLINE | ID: mdl-35416643

RESUMEN

Escalating energy demand, the depletion of fossil fuels, and abnormal climate change are recognized as the key challenges in the 21st century. The valorization of biomass and plastic, representing the most abundant natural and man-made polymers, respectively, as alternatives to fossil fuel is one of the promising solutions to creating a carbon-neutral, waste-free society. Catalysis is an essential tool for manipulating energy transformations via bond-breaking and bond-forming principles. To producing chemicals and fuels via biomass valorization and plastic upcycling, the cleavage of C-O and C-C bonds is the major catalytic route, given that the two are mainly constructed by various interunit C-O and C-C linkages. In this work, a consensus concerning the catalytic mechanism is reached: the activities for the cleavage of C-O and C-C bonds highly depend on the catalyst ability to activate the C-O and C-C bonds. Among the catalysts reported, NbOx-based catalysts show a unique, superstrong ability to activate C-O and C-C bonds. While research on biomass valorization over NbOx-based catalysts maintains its momentum, plastic upcycling driven by an efficient NbOx-based catalyst capable of activating C-O and C-C bonds is quickly catching up. Therefore, deepening the understanding of NbOx-based catalysts for the activation of C-O and C-C bonds is of importance to further drive biomass valorization and plastic upcycling, even in many other related areas. Herein, we present progress on the activation of C-O and C-C bonds in waste carbon resources, with an emphasis on our own work in using NbOx-based catalysts. First, we introduce NbOx-based catalysts for the activation of C-O and C-C bonds in biomass with a special focus on explaining how NbOx-based catalysts activate C-O and C-C bonds and why NbOx-based catalysts can activate C-O and C-C bonds so efficiently. Then, unified descriptors to embody the abilities to extract O from oxygenated compounds and an adsorbed benzene ring, namely "oxygen affinity" and "benzene ring affinity", were defined to standardize C-O and Carom-Caliph activation chemistry. Furthermore, we highlight the emerging opportunities of NbOx-based catalysts for plastic upcycling by learning the wisdom accumulated from the activation of C-O and C-C bonds in biomass. Finally, our own insights into future recommendations in this promising field are provided.


Asunto(s)
Benceno , Carbono , Biomasa , Catálisis , Humanos , Plásticos
7.
Inorg Chem ; 62(19): 7525-7532, 2023 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-37133541

RESUMEN

Electrocatalytic nitrate reduction reaction (ENO3RR) is an alternative, sustainable, and environmentally friendly value-added NH3 synthesis method under ambient conditions relative to the traditional Haber-Bosch process; however, its low NH3 yield, low Faradaic efficiency (FE), low selectivity, and low conversion rate severely restrict the development. In this work, a Cu2+1O/Ag-CC heterostructured electrocatalyst was successfully fabricated by constructing a heterogeneous interface between Cu2+1O and Ag for selective electrochemical nitrate-to-ammonia conversion. The construction of the heterogeneous interface effectively promotes the synergistic effect of the catalytically active components Cu2+1O and Ag, which enhances the material conductivity, accelerates the interfacial electron transfer, and exposes more active sites, thus improving the performance of ENO3RR. Such Cu2+1O/Ag-CC manifests a high NH3 yield of 2.2 mg h-1 cm-2 and a notable ammonia FE of 85.03% at the optimal applied potential of -0.74 V vs RHE in a relatively low concentration of 0.01 M NO3--containing 0.1 M KOH. Moreover, it shows excellent electrochemical stability during the cycle tests. Our study not only provides an efficient catalyst for ammonia electro-synthesis from ENO3RR but also an effective strategy for the construction of ENO3RR electrocatalysts for electrocatalytic applications.

8.
Inorg Chem ; 62(33): 13338-13347, 2023 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-37599583

RESUMEN

Oxygen evolution reaction (OER) is a limiting reaction for highly efficient water electrolysis. Thus, the development of cost-effective and highly efficient OER catalysts is the key to large-scale water electrolysis for hydrogen production. Herein, by using an interfacial engineering strategy, a unique nanoflower-like Fe1-xNix(PO3)2/Ni2P/NF heterostructure with abundant heterogeneous interfaces is successfully fabricated. The catalyst exhibits excellent OER catalytic activity in alkaline fresh water and alkaline natural seawater at high current densities, which only, respectively, requires overpotentials of 318 and 367 mV to drive 1000 mA cm-2 in fresh water and natural seawater both containing 1 M KOH. Furthermore, Fe1-xNix(PO3)2/Ni2P/NF demonstrates excellent durability, which can basically remain stable for 80 h during the electrocatalytic OER processes, respectively, in alkaline fresh water and natural seawater. This work provides a new construction strategy for designing highly efficient electrocatalysts for OER at high current densities both in alkaline fresh water and in natural seawater.

9.
Clin Rehabil ; 37(7): 986-1008, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36540949

RESUMEN

OBJECTIVE: This systematic review summarized the rehabilitation recommendations for treating and managing knee osteoarthritis (OA) in practice guidelines and evaluated their applicability and quality using the Appraisal of Guidelines for Research and Evaluation (AGREE) II instrument. DATA SOURCES: PubMed, the Cochrane Library, EMBASE, CINAHL, PEDro, Guideline central, Guideline International Network and Agency for Healthcare Research and Quality (AHRQ) were used to search for relevant studies published between 1 January 2008 and 31 May 2022. METHODS: AGREE II was used to evaluate the included guidelines quality, SPSS 25.0 statistical software was used for data analysis, and the intra-group correlation coefficient value was calculated to verify the consistency between the raters. The two-way random effects model was used to calculate concordance scores, and each domain's total scores were calculated. Additionally, the median and interquartile range for domain and total scores were calculated. RESULTS: Twenty-four guidelines recommending knee OA rehabilitation were included. Inter-rater consistency evaluation ranged from 0.62 to 0.90. The domains where the guideline's overall and rehabilitation parts scored highest and lowest were scope and purpose (domain 1) and applicability (domain 5), respectively. The highly recommended rehabilitation opinions included aerobic exercise programs (21/24), weight control (16/24), self-education and management (16/24), gait/walking aids (7/24), and tai chi (6/24). However, the orthopedic insole and hot/cold therapy roles remain controversial. CONCLUSION: The clinical practice guidelines' overall quality for knee OA rehabilitation is good; however, the applicability is slightly poor. Therefore, we should improve the promoting factors and hindering factors, guideline application recommendations, tools, and resources when developing relevant guidelines.


Asunto(s)
Medicina , Osteoartritis de la Rodilla , Estados Unidos , Humanos , Crioterapia , Marcha , Zapatos
10.
Int J Neurosci ; 133(3): 269-277, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33784949

RESUMEN

Background and purpose: Parkinson's disease is a common degenerative disease of the central nervous system with complex pathogenesis. More and more studies have found that inflammatory response promotes the occurrence and development of the disease, in which the activation of microglia plays an important role. PGC-1α (peroxisome proliferator activated receptor-γ coactivator-1α) is the main factor in mitochondrial biogenetic, and is closely related to the inflammatory response. Our immunofluorescence test results showed that PGC-1α and microglia (Iba1) have double-labeled phenomenon. The expression of microglia in the MPTP (1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine) group increased, and PGC-1α/Iba1 double label increased. To test whether lowering the expression of PGC-1α can reduce the activation of microglia and protect the substantia nigra dopaminergic neurons, we constructed PGC-1α interference lentivirus.Methods: Immunofluorescence, western blot, and ELISA were used to detect microglial phenotype.Results: The results showed that PGC-1α interfering with lentivirus can transfect microglial cells in substantia nigra, and the PGC-1α protein level decreased in substantia nigra accordingly; TH protein expression had no statistical difference compared with MPTP group; PGC-1α interfering lentivirus reduced microglia number and activation, and at the same time the expression of iNOS and Arg1 significantly reduced compared with MPTP group. The IL-6 expression in blood detected using ELISA was significantly reduced compared with MPTP group.Conclusion: PGC-1α downregulation inhibited microglia activity, and both M1 and M2 microglial activities are reduced.


Asunto(s)
Microglía , Enfermedad de Parkinson , Ratones , Animales , Microglía/metabolismo , ARN Interferente Pequeño/metabolismo , Sustancia Negra/metabolismo , Enfermedad de Parkinson/metabolismo , Inflamación/metabolismo , Neuronas Dopaminérgicas/metabolismo , Ratones Endogámicos C57BL
11.
Inorg Chem ; 61(18): 7165-7172, 2022 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-35465676

RESUMEN

The electrocatalytic nitrogen reduction reaction (ECNRR) is a sustainable and environmentally friendly method for NH3 synthesis under environmental conditions relative to the Haber-Bosch process; however, its low selectivity (Faradaic efficiency (FE)) and low NH3 yield impede the progress. Herein, benefiting from the application of the interface engineering strategy, a multicomponent TiO2/Ag/Cu7S4@Se-CC heterogeneous electrocatalyst with a unique structure was successfully fabricated, generating a unique sandwich structure by using a Ag layer as an electric bridge intercalated between TiO2 and Cu7S4, in which the optimized catalyst can accelerate the electron transfer efficiency. Moreover, through the electronic structure adjustment, an electron-deficient region was constructed, which can inhibit the H2 adsorption but enhance the N2 adsorption, thereby improving the selectivity and the catalytic activity. Significantly, the FE and NH3 yield of TiO2/Ag/Cu7S4@Se-CC reached 51.05 ± 0.16% and 39.16 ± 2.31 µg h-1 cm-2, in which the FE is among the highest non-precious metal-based NRR electrocatalysts in alkaline electrolytes reported. This study provides insight into the rational design and construction of NRR electrocatalysts for electrocatalytic applications.

12.
Metab Brain Dis ; 37(2): 451-462, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34817756

RESUMEN

Parkinson's disease (PD) is a neurodegenerative disease with increasing incidence in aged populations, second only to Alzheimer's disease. Increasing evidence has shown that inflammation plays an important role in the occurrence and development of Parkinson's disease. Growing evidence has shown that AMP-activated protein kinase (AMPK) and NF-κB are closely related to inflammation. Glucagon-like peptide 1 (GLP-1) is a hormone that is primarily secreted by intestinal endocrine L cells, and it has a variety of physiology through binding to GLP-1 receptor. GLP-1can be used for treatment of type 2 diabetes. In addition, GLP-1 also has anti-neuroinflammation activity. However, the exact mechanism behind how GLP-1 regulates neuroinflammation remains unclear. This study was designed to examine the effect of liraglutide on 1-methyl-4-phenyl-1,2,3,6- tetrahydropyridine (MPTP)-induced injury in mice and its potential mechanism of action. Results showed that liraglutide dose-dependently ameliorated mouse behavior including swimming time and locomotor activity, increased the number of tyrosine hydroxylase (TH)-positive neurons and protein level, and reduced Iba1 and GFAP expression in the substantia nigra (SN). Liraglutide treatment also increased p-AMPK expression and reduced NF-κB protein level. Applying the AMPK inhibitor Dorsomorphin (Compound C) reversed the effect of liraglutide-reducing p-AMPK and increasing NF-κB expression. Finally, GFAP protein level increased, along with a decrease in TH expression. In conclusion, these results suggest that liraglutide can suppress neuroinflammation. Moreover, this effect is mediated through the AMPK/NF-κB signaling pathway.


Asunto(s)
Diabetes Mellitus Tipo 2 , Enfermedades Neurodegenerativas , Fármacos Neuroprotectores , Enfermedad de Parkinson , Proteínas Quinasas Activadas por AMP , Animales , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Modelos Animales de Enfermedad , Inflamación/tratamiento farmacológico , Liraglutida/farmacología , Liraglutida/uso terapéutico , Ratones , FN-kappa B , Fármacos Neuroprotectores/farmacología , Fármacos Neuroprotectores/uso terapéutico , Enfermedad de Parkinson/tratamiento farmacológico , Enfermedad de Parkinson/metabolismo
13.
J Cell Physiol ; 236(8): 5921-5936, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-33481281

RESUMEN

Plant bugs (Miridae species) have become major agricultural pests that cause increasing and severe economic damage. Plant-mediated RNA interference (RNAi) is emerging as an eco-friendly, efficient, and reliable strategy for pest management. In this study, we isolated and characterized a lethal gene of Apolygus lucorum and named it Apolygus lucorum LIM (AlLIM), which produced A. lucorum mortality rates ranging from 38% to 81%. Downregulation of the AlLIM gene expression in A. lucorum by injection of a double-stranded RNA (dsRNA) led to muscle structural disorganization that resulted in metamorphosis deficiency and increased mortality. Then we constructed a plant expression vector that enabled transgenic cotton to highly and stably express dsRNA of AlLIM (dsAlLIM) by Agrobacterium-mediated genetic transformation. In the field bioassay, dsAlLIM transgenic cotton was protected from A. lucorum damage with high efficiency, with almost no detectable yield loss. Therefore, our study successfully provides a promising genetically modified strategy to overpower A. lucorum attack.


Asunto(s)
Gossypium/parasitología , Heterópteros/genética , Insectos/genética , Interferencia de ARN/inmunología , Animales , Plantas/parasitología
14.
BMC Neurosci ; 22(1): 56, 2021 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-34525970

RESUMEN

BACKGROUND: NRXN1 deletions are identified as one of major rare risk factors for autism spectrum disorder (ASD) and other neurodevelopmental disorders. ASD has 30% co-morbidity with epilepsy, and the latter is associated with excessive neuronal firing. NRXN1 encodes hundreds of presynaptic neuro-adhesion proteins categorized as NRXN1α/ß/γ. Previous studies on cultured cells show that the short NRXN1ß primarily exerts excitation effect, whereas the long NRXN1α which is more commonly deleted in patients involves in both excitation and inhibition. However, patient-derived models are essential for understanding functional consequences of NRXN1α deletions in human neurons. We recently derived induced pluripotent stem cells (iPSCs) from five controls and three ASD patients carrying NRXN1α+/- and showed increased calcium transients in patient neurons. METHODS: In this study we investigated the electrophysiological properties of iPSC-derived cortical neurons in control and ASD patients carrying NRXN1α+/- using patch clamping. Whole genome RNA sequencing was carried out to further understand the potential underlying molecular mechanism. RESULTS: NRXN1α+/- cortical neurons were shown to display larger sodium currents, higher AP amplitude and accelerated depolarization time. RNASeq analyses revealed transcriptomic changes with significant upregulation glutamatergic synapse and ion channels/transporter activity including voltage-gated potassium channels (GRIN1, GRIN3B, SLC17A6, CACNG3, CACNA1A, SHANK1), which are likely to couple with the increased excitability in NRXN1α+/- cortical neurons. CONCLUSIONS: Together with recent evidence of increased calcium transients, our results showed that human NRXN1α+/- isoform deletions altered neuronal excitability and non-synaptic function, and NRXN1α+/- patient iPSCs may be used as an ASD model for therapeutic development with calcium transients and excitability as readouts.


Asunto(s)
Trastorno del Espectro Autista/genética , Proteínas de Unión al Calcio/genética , Redes Reguladoras de Genes/fisiología , Células Madre Pluripotentes Inducidas/fisiología , Moléculas de Adhesión de Célula Nerviosa/genética , Neuronas/fisiología , Adolescente , Trastorno del Espectro Autista/metabolismo , Proteínas de Unión al Calcio/metabolismo , Línea Celular , Células Cultivadas , Niño , Preescolar , Femenino , Humanos , Masculino , Moléculas de Adhesión de Célula Nerviosa/metabolismo , Adulto Joven
15.
Opt Express ; 29(7): 9991-9999, 2021 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-33820160

RESUMEN

Based on the delicate interference behavior of light in the far field, the optical super-oscillatory phenomenon has been successfully applied in non-invasive sub-diffraction focusing and super-resolution imaging in recent years. However, the optical super-oscillatory field is particularly sensitive to the change of incident angle, leading to a limited field of view for super-resolution imaging. In this paper, a super-oscillatory metasurface doublet is proposed to achieve far-field sub-diffraction focusing with an incident angle of up to 25°. The constructed doublet, consisting of high-aspect-ratio rectangular nanopillars with high efficiency, is further demonstrated through a full-wave simulation, and the numerical results indicate that the sub-diffraction foci with about 0.75 times of the diffraction limit is achieved for different incident angles. The proposed super-oscillatory metasurface doublet may find intriguing applications in label-free super-resolution microscopy and optical precise fabrication.

16.
J Plant Res ; 134(3): 613-623, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33723703

RESUMEN

Abiotic stresses such as drought, salinity, and heat affect plant growth and development. Karelinia caspica is a unique perennial herb that grows in desert area for a long time and has strong tolerance to environmental stresses. In order to explore the functions of the Na+/H+ antiporter gene from eremophyte K. caspica (KcNHX1) in the abiotic stress response of K. caspica and the underlying regulatory mechanisms, we constructed a vector overexpressing KcNHX1 and transformed it into Arabidopsis thaliana. The physiological results showed that the overexpression of KcNHX1 in A. thaliana not only enhanced the plant's tolerance to salt stress, but also enhanced its tolerance to drought and heat stress at the seedling stage. In addition, KcNHX1-overexpressing plants exhibited enhanced reproductive growth under high temperature, which was mediated by increased auxin accumulation. Taken together, our results indicate that KcNHX1 from an eremophyte can be used as a candidate gene to improve multiple stress tolerance in other plants.


Asunto(s)
Arabidopsis , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis , Proteínas de Transporte de Catión , Sequías , Regulación de la Expresión Génica de las Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Modificadas Genéticamente/metabolismo , Salinidad , Intercambiadores de Sodio-Hidrógeno , Estrés Fisiológico
17.
Angew Chem Int Ed Engl ; 60(10): 5527-5535, 2021 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-33269513

RESUMEN

The upgrading of plastic waste is one of the grand challenges for the 21st century owing to its disruptive impact on the environment. Here, we show the first example of the upgrading of various aromatic plastic wastes with C-O and/or C-C linkages to arenes (75-85 % yield) via catalytic hydrogenolysis over a Ru/Nb2 O5 catalyst. This catalyst not only allows the selective conversion of single-component aromatic plastic, and more importantly, enables the simultaneous conversion of a mixture of aromatic plastic to arenes. The excellent performance is attributed to unique features including: (1) the small sized Ru clusters on Nb2 O5 , which prevent the adsorption of aromatic ring and its hydrogenation; (2) the strong oxygen affinity of NbOx species for C-O bond activation and Brønsted acid sites for C-C bond activation. This study offers a catalytic path to integrate aromatic plastic waste back into the supply chain of plastic production under the context of circular economy.

18.
Mediators Inflamm ; 2020: 8297134, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32454795

RESUMEN

PURPOSE: To evaluate the regulating effect of Notch-Hes1 signaling on IL-17A+ γδ +T cell expression and IL-17A secretion in mouse psoriasis-like skin inflammation. MATERIALS AND METHODS: Experimental mice were randomly divided into control group, model group (5% imiquimod- (IMQ-) treated mice), and intervention group (IMQ and γ-secretase inhibitor DAPT cotreated mice). The severity of psoriasis-like skin inflammation was evaluated by target lesion score based on the clinical psoriasis area and severity index (PASI). Flow cytometry detected IL-17A+ γδ +T cell percentage. Quantitative real-time RT-PCR detected Hes1 mRNA expression. Enzyme-linked immunosorbent assay and western blot measured IL-17A serum concentration and protein expression. Additionally, splenic single cells from model mice were treated by DAPT to further evaluate the inhibitory effect of blocking Notch-Hes1 signaling on IL-17A+ γδ +T cell differentiation and IL-17A secretion. RESULTS: The spleen index, IL-17A+ γδ +T cell percentage, Hes1 mRNA expression, IL-17A serum concentration, and protein expression were all significantly higher in model mice than control mice, while dramatically reduced in intervention mice by DAPT treatment, which also obviously alleviated the target lesion score, epidermal hyperplasia, and dermal inflammatory cell infiltration of intervention mice. In vitro study demonstrated that DAPT treatment could result in dose-dependent decrease of IL-17A+ γδ +T cell percentage and IL-17A secretion in splenic single cells of model mice.


Asunto(s)
Interleucina-17/metabolismo , Psoriasis/metabolismo , Receptores Notch/metabolismo , Linfocitos T/citología , Factor de Transcripción HES-1/metabolismo , Animales , Citocinas/metabolismo , Ensayo de Inmunoadsorción Enzimática , Citometría de Flujo , Imiquimod/uso terapéutico , Inflamación/metabolismo , Masculino , Ratones , Ratones Endogámicos BALB C , Transducción de Señal , Piel/metabolismo , Bazo/metabolismo , Linfocitos T/inmunología , Células Th17/metabolismo
19.
Biomed Eng Online ; 18(1): 122, 2019 Dec 23.
Artículo en Inglés | MEDLINE | ID: mdl-31870380

RESUMEN

BACKGROUND: Bone is a hierarchically structured composite material, and different hierarchical levels exhibit diverse material properties and functions. The stress and strain distribution and fluid flow in bone play an important role in the realization of mechanotransduction and bone remodeling. METHODS: To investigate the mechanotransduction and fluid behaviors in loaded bone, a multiscale method was developed. Based on poroelastic theory, we established the theoretical and FE model of a segment bone to provide basis for researching more complex bone model. The COMSOL Multiphysics software was used to establish different scales of bone models, and the properties of mechanical and fluid behaviors in each scale were investigated. RESULTS: FE results correlated very well with analytical in macroscopic scale, and the results for the mesoscopic models were about less than 2% different compared to that in the macro-mesoscale models, verifying the correctness of the modeling. In macro-mesoscale, results demonstrated that variations in fluid pressure (FP), fluid velocity (FV), von Mises stress (VMS), and maximum principal strain (MPS) in the position of endosteum, periosteum, osteon, and interstitial bone and these variations can be considerable (up to 10, 8, 4 and 3.5 times difference in maximum FP, FV, VMS, and MPS between the highest and the lowest regions, respectively). With the changing of Young's modulus (E) in each osteon lamella, the strain and stress concentration occurred in different positions and given rise to microscale spatial variations in the fluid pressure field. The heterogeneous distribution of lacunar-canalicular permeability (klcp) in each osteon lamella had various influence on the FP and FV, but had little effect on VMS and MPS. CONCLUSION: Based on the idealized model presented in this article, the presence of endosteum and periosteum has an important influence on the fluid flow in bone. With the hypothetical parameter values in osteon lamellae, the bone material parameters have effect on the propagation of stress and fluid flow in bone. The model can also incorporate alternative material parameters obtained from different individuals. The suggested method is expected to provide dependable biological information for better understanding the bone mechanotransduction and signal transduction.


Asunto(s)
Huesos/fisiología , Elasticidad , Análisis de Elementos Finitos , Fenómenos Biomecánicos , Huesos/metabolismo , Módulo de Elasticidad , Permeabilidad , Porosidad , Estrés Mecánico , Soporte de Peso
20.
Proc Natl Acad Sci U S A ; 113(5): 1327-32, 2016 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-26768847

RESUMEN

Polyploidy is much rarer in animals than in plants but it is not known why. The outcome of combining two genomes in vertebrates remains unpredictable, especially because polyploidization seldom shows positive effects and more often results in lethal consequences because viable gametes fail to form during meiosis. Fortunately, the goldfish (maternal) × common carp (paternal) hybrids have reproduced successfully up to generation 22, and this hybrid lineage permits an investigation into the genomics of hybridization and tetraploidization. The first two generations of these hybrids are diploids, and subsequent generations are tetraploids. Liver transcriptomes from four generations and their progenitors reveal chimeric genes (>9%) and mutations of orthologous genes. Characterizations of 18 randomly chosen genes from genomic DNA and cDNA confirm the chimera. Some of the chimeric and differentially expressed genes relate to mutagenesis, repair, and cancer-related pathways in 2nF1. Erroneous DNA excision between homologous parental genes may drive the high percentage of chimeric genes, or even more potential mechanisms may result in this phenomenon. Meanwhile, diploid offspring show paternal-biased expression, yet tetraploids show maternal-biased expression. These discoveries reveal that fast and unstable changes are mainly deleterious at the level of transcriptomes although some offspring still survive their genomic abnormalities. In addition, the synthetic effect of genome shock might have resulted in greatly reduced viability of 2nF2 hybrid offspring. The goldfish × common carp hybrids constitute an ideal system for unveiling the consequences of intergenomic interactions in hybrid vertebrate genomes and their fertility.


Asunto(s)
Cruzamientos Genéticos , Carpa Dorada/genética , Ploidias , Animales , Cromosomas , Perfilación de la Expresión Génica , Hibridación Fluorescente in Situ
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