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1.
Genes (Basel) ; 14(11)2023 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-38002992

RESUMO

Uncoupling protein 3 (Ucp3) is an important transporter within mitochondria and is mainly expressed in skeletal muscle, brown adipose tissue and the myocardium. However, the effects of Ucp3 on myogenic differentiation are still unclear. This study evaluated the effects of Ucp3 on myogenic differentiation, myofiber type and energy metabolism in C2C12 cells. Gain- and loss-of-function studies revealed that Ucp3 could increase the number of myotubes and promote the myogenic differentiation of C2C12 cells. Furthermore, Ucp3 promoted the expression of the type IIb myofiber marker gene myosin heavy chain 4 (Myh4) and decreased the expression of the type I myofiber marker gene myosin heavy chain 7 (Myh7). In addition, energy metabolism related to the expression of PPARG coactivator 1 alpha (Pgc1-α), ATP synthase, H+ transportation, mitochondrial F1 complex, alpha subunit 1 (Atp5a1), lactate dehydrogenase A (Ldha) and lactate dehydrogenase B (Ldhb) increased with Ucp3 overexpression. Ucp3 could promote the myogenic differentiation of type IIb myotubes and accelerate energy metabolism in C2C12 cells. This study can provide the theoretical basis for understanding the role of Ucp3 in energy metabolism.


Assuntos
Fibras Musculares Esqueléticas , Cadeias Pesadas de Miosina , Proteína Desacopladora 3/genética , Proteína Desacopladora 3/metabolismo , Cadeias Pesadas de Miosina/genética , Cadeias Pesadas de Miosina/metabolismo , Linhagem Celular , Fibras Musculares Esqueléticas/metabolismo , Diferenciação Celular/genética
2.
Materials (Basel) ; 16(22)2023 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-38005061

RESUMO

Nickel is widely used in industrial processes and plays a crucial role in many applications. However, most of the nickel resource mainly exists as nickel oxide in laterite nickel ore with complex composition, resulting in difficulty in upgrading the nickel content using physical separation methods. In this study, high-grade ferronickel concentrates were obtained through a carbothermal reduction and magnetic separation using laterite nickel ore and anthracite as raw materials. The effects of different types of additives (CaF2, Na2SO4, and H3BO3), carbon ratio (the molar ratio of oxygen atoms in the laterite nickel ore to carbon atoms in anthracite), and grinding time on the recoveries and grades of ferronickel concentrates were experimentally investigated, along with the microstructure and chemical composition of the products. CaF2 was proved to be the primary active additive in the aggregation and growth of the ferronickel particles and the improvement of the grade of the product. Under the optimal conditions of CaF2 addition of 9.85 wt%, carbon ratio of 1.4, and grinding time of 240 s, high-grade magnetically separable ferronickel concentrate with nickel grade 8.93 wt% and iron grade 63.96 wt% was successfully prepared. This work presents a practical method for the highly efficient recovery and utilization of iron and nickel from low-grade laterite nickel ore, contributing to the development of strategies for the sustainable extraction and utilization of nickel resources.

3.
Expert Opin Drug Saf ; : 1-8, 2023 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-37427985

RESUMO

BACKGROUND: There are no local or international guidelines or consensus on the use of mAbs against the rabies virus. RESEARCH DESIGN AND METHODS: An expert group in the field of rabies prevention and control formulated the consensus presented in this paper. RESULTS: Class III exposed persons to rabies for the first time; Identify type II exposed persons with immune deficiency; those who are first exposed to Class II and re-exposed to Class III within 7 days. They can use ormutivimab injection after completing the PEP wound treatment. In the case of injection restrictions or a wound that is difficult to detect, it is recommended that the entire Ormutivimab dose be infiltrated close to the wound. For severe multi-wound bites, the recommended dosage of ormutivimab is 20 IU/kg. If the recommended dose cannot meet all of the wound infiltration requirements, appropriate dilution can be conducted at a dilution ratio of 3 ~ 5 times. If the requirements for infiltration cannot be met after dilution, it is recommended that the dosage be increased with caution (maximum dosage, 40 IU/kg). The use of Ormutivimab is safe and effective without any contraindications by all age groups. CONCLUSIONS: This consensus standardizes clinical use of Ormutivimab, improves post-exposure prophylaxis of rabies in China, reduces infection rate.

4.
J Hazard Mater ; 443(Pt A): 130211, 2023 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-36367469

RESUMO

Aqueous Cr(VI) pollution is an emerging environmental issue. Herein, a sphere-like ZnFe2O4 catalyst with a size of ∼430 nm was prepared by a solvothermal method, by which the aqueous Cr(VI) in a 50 mL solution with concentration of 50 mg/L was completely removed after 10 min-microwave (MW) irradiation. "Surface temperature visualization" tests and COMSOL simulations showed that the surface temperature of the as-prepared ZnFe2O4 catalysts could be as high as > 1000 °C only after 300 s MW irradiation, and the work function calculations and scavenging experiments demonstrated that the excited electrons derived by the "hot spots" effect of the ZnFe2O4 catalysts reduced the Cr(VI) to Cr(III). Kinetic reaction process of the reduction of *Cr2O72- to *CrO3H3 over the ZnFe2O4 catalysts was clarified by using DFT calculation, and the results indicated that *Cr2O72- adsorbed on the Fe atoms was more easily to be reduced, and that Fe atoms played more significant roles than the Zn and O atoms in ZnFe2O4 catalysts. The present study not only proves that the MW induced ZnFe2O4 catalytic reduction was promising for ultrafast remediation of toxic Cr(VI), but also provides a new insight into the corresponding mechanism.

5.
Materials (Basel) ; 15(23)2022 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-36499835

RESUMO

B4C-particle-reinforced Al (B4Cp/Al) composites are widely used in various areas, e.g., armors, electronic packaging and fuel storage, owing to their several outstanding properties including high specific rigidity, excellent wear resistance and light weight. Selective laser melting (SLM) is favored in manufacturing complex components because of its high raw material utilization rate and high efficiency. In this work, a B4Cp/Al composite was successfully synthesized by SLM, and the effects of one of the most important parameters, scanning speed (100-700 mm/s), on the phase composition, density, microhardness and tribological properties of the samples were investigated. The microhardness, relative density and dry-sliding wear resistance of as-prepared B4Cp/Al composites were improved with the decrease in scanning speed, and the sample fabricated at a scanning speed of 100 mm/s exhibited a relative density as high as about 97.1%, and a maximum microhardness of ~180 HV0.1 (approximately six times more than that of the SLM-formed pure Al sample, 31 HV0.1), a minimum wear rate of 4.2 × 10-5 mm3·N-1·m-1 and a corresponding friction coefficient of 0.41. In addition, abrasive wear, adhesive wear and oxidation wear were found to be behind the overall wear behavior of as-prepared B4Cp/Al composites.

6.
Materials (Basel) ; 15(10)2022 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-35629547

RESUMO

Magnesia-based refractory is widely used in high-temperature industries; its easy hydration is, however, a key concern in refractory processing. Understanding the hydration mechanism of MgO will help in solving its hydration problem. Herein, the hydration behavior of (MgO)n (n = 1-6) at the molecular level and the effect mechanisms of several anti-hydration agents on the hydration of (MgO)4 were investigated with first-principles calculations. The results indicated that the following: (1) The smaller the (MgO)n cluster size, the more favorable the hydration of MgO and the tendency to convert into Mg(OH)2 crystal; (2) Anti-hydration agents can coordinate with the unsaturated Mg atom of (MgO)4 to form a bond, increasing the coordination number of Mg, thus reducing its activity when reacting with H2O; (3) The greater the number of -COOH groups and the longer the chain length in the anti-hydration agents, the better its effect of inhibiting the hydration of MgO. These findings could enhance the understanding of the mechanism of hydration of MgO and provide theoretical guidance for the design of novel anti-hydration agents.

7.
Chemosphere ; 303(Pt 1): 134756, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35533935

RESUMO

Three-dimensional (3D) porous architecture has attracted considerable attention in remediation of oil/water emulsion. In present work, an air superhydrophilic/superoleophobic diatomite porous ceramic (AS-DC) was prepared, using SiO2 whiskers modified diatomite ceramic as the substrate and FS-50 as the modifier. The interconnected SiO2 whiskers intertwined on the skeleton of ceramic block forming a 3D network structure, which not only improved the wettability of AS-DC, but also reinforced its mechanical property (about 2.5 MPa of compressive strength). The as-prepared AS-DC with intrinsically superoleophobicity (154°) and superhydrophilicity (0°) exhibited an underwater oil contact angle of 161°, suggesting a multifunctional separation capability. By simply assembling AS-DC with pipes and a pump, it could not only separate the surfactant-stabilized oil-in-water emulsion in a permeation flux as high as 107.8 kg min-1 m-2 with a selectivity of >95%, but also collect the clean water from the floating oil/water mixture in a flux of 197.4 kg min-1 m-2 and a selectivity of ∼99%. In addition, the AS-DC was resistant to the salt/acid/alkaline corrosion and temperature fluctuation. The mechanical/chemical firmness of AS-DC renders it tremendous potential as a robust 3D architecture in real application for purification of oil/water mixture.


Assuntos
Óleos , Dióxido de Silício , Cerâmica , Terra de Diatomáceas , Emulsões , Interações Hidrofóbicas e Hidrofílicas , Óleos/química , Porosidade
8.
J Hazard Mater ; 417: 125979, 2021 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-34015716

RESUMO

Oil-spill accident is a severe globally concerned environmental issue. In this work, a Joule-heatable bird-nest-bioinspired/carbon nanotubes-modified sepiolite porous ceramic (JBN/CM-SC) was developed, using inexpensive sepiolite porous ceramics as the substrate and carbon nanotubes (CNTs) derived from waste plastics as the modifier. The former exhibited outstanding mechanical property (1.7 MPa of compressive strength), gas permeability (9.1 × 10-11 m2), thermal conductivity (0.215 W·m-1·K-1) and thermal/chemical stability. As expected, the deposited CNTs not only conferred a hydrophobic surface, but also resulted in a Joule-heating ability of intrinsically non-conductive ceramics. As-prepared JBN/CM-SC demonstrated a separation rate as high as 120-200 kg·s-1·m-2 for oil recovery and a high selectivity of over 95%. The Joule heat generated by the heated JBN/CM-SC could in-situ reduce the oil-viscosity, remarkably increasing the oil-diffusion. The separation rate was enhanced by ~12 times with respect to that of the non-heated counterpart. In addition, the idea of modular design was proposed. By simply combining JBN/CM-SC components with pipes and a pump, a continuous in-situ collection of oil from an oil/water mixture was realized, providing an efficient, sturdy, and continuous approach to recover the spilled oil in an oil-spill accident.

9.
Genome Biol ; 22(1): 23, 2021 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-33430931

RESUMO

BACKGROUND: Tartary buckwheat (Fagopyrum tataricum) is a nutritionally balanced and flavonoid-rich crop plant that has been in cultivation for 4000 years and is now grown globally. Despite its nutraceutical and agricultural value, the characterization of its genetics and its domestication history is limited. RESULTS: Here, we report a comprehensive database of Tartary buckwheat genomic variation based on whole-genome resequencing of 510 germplasms. Our analysis suggests that two independent domestication events occurred in southwestern and northern China, resulting in diverse characteristics of modern Tartary buckwheat varieties. Genome-wide association studies for important agricultural traits identify several candidate genes, including FtUFGT3 and FtAP2YT1 that significantly correlate with flavonoid accumulation and grain weight, respectively. CONCLUSIONS: We describe the domestication history of Tartary buckwheat and provide a detailed resource of genomic variation to allow for genomic-assisted breeding in the improvement of elite cultivars.


Assuntos
Domesticação , Fagopyrum/genética , Fagopyrum/metabolismo , Estudo de Associação Genômica Ampla , China , Flavonoides/metabolismo , Regulação da Expressão Gênica de Plantas , Técnicas Genéticas , Variação Genética , Melhoramento Vegetal , Polimorfismo de Nucleotídeo Único
10.
Nanomaterials (Basel) ; 10(11)2020 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-33167457

RESUMO

Loading a noble metal on Bi4Ti3O12 could enable the formation of the Schottky barrier at the interface between the former and the latter, which causes electrons to be trapped and inhibits the recombination of photoelectrons and photoholes. In this paper, AgPt/Bi4Ti3O12 composite photocatalysts were prepared using the photoreduction method, and the effects of the type and content of noble metal on the photocatalytic performance of the catalysts were investigated. The photocatalytic degradation of rhodamine B (RhB) showed that the loading of AgPt bimetallic nanoparticles significantly improved the catalytic performance of Bi4Ti3O12. When 0.10 wt% noble metal was loaded, the degradation rate for RhB of Ag0.7Pt0.3/Bi4Ti3O12 was 0.027 min-1, which was respectively about 2, 1.7 and 3.7 times as that of Ag/Bi4Ti3O12, Pt/Bi3Ti4O12 and Bi4Ti3O12. The reasons may be attributed as follows: (i) the utilization of visible light was enhanced due to the surface plasmon resonance effect of Ag and Pt in the visible region; (ii) Ag nanoparticles mainly acted as electron acceptors to restrain the recombination of photogenerated electron-hole pairs under visible light irradiation; and (iii) Pt nanoparticles acted as electron cocatalysts to further suppress the recombination of photogenerated electron-hole pairs. The photocatalytic performance of Ag0.7Pt0.3/Bi4Ti3O12 was superior to that of Ag/Bi4Ti3O12 and Pt/Bi3Ti4O12 owing to the synergistic effect between Ag and Pt nanoparticles.

11.
Anal Chem ; 92(21): 14309-14313, 2020 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-33138379

RESUMO

Fractionation information on arsenic (As) in complex samples, particularly solid samples, is of immense interest. Herein, selective extraction of various As species adsorbed onto ferrihydrite as the model substrate was online-adapted to inductively coupled plasma-mass spectrometry (ICP-MS) for sensitive detection. The As-adsorbed ferrihydrite sample was loaded into a homemade online sequential elution device using two commercially available micropipette tips, and then, each fraction of As including nonspecifically adsorbed, specifically adsorbed, iron oxide bonded, and residual species was successively extracted for ICP-MS detection, with H2O, NH4NO3, NH4H2PO4, ammonium oxalate, and HF as the eluents, respectively. While no water-soluble As was detected, the fraction of As bonded to iron oxide was detected as the dominant species (>80%), and the specifically adsorbed As and residual As also accounted for a substantial amount (10%). The method had a detection limit of 0.008 µg/kg for As(III) and 0.013 µg/kg for As(V), with merits such as extremely low sample consumption, high throughput, and minimized experimental manipulation, presenting an alternative strategy for sensitive fractionation analysis of As adsorbed onto solid substrates (e.g., iron oxides, etc.).


Assuntos
Arsênio/análise , Arsênio/isolamento & purificação , Fracionamento Químico/métodos , Compostos Férricos/química , Espectrometria de Massas , Adsorção , Arsênio/química , Limite de Detecção , Propriedades de Superfície
12.
Anal Bioanal Chem ; 411(18): 4049-4054, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30635664

RESUMO

More than 200 toxic substances (including narcotic drugs, psychotropic drugs, organic phosphorus compounds, carbamates, pyrethroids and other pesticides, veterinary drugs, rodenticides, natural toxins, and other drugs) were identified and quantified using an ion-trap mass spectrometer. The advantages of this technique-its selectivity, accuracy, precision, utilization of only small amounts of the sample, and short analysis time for a single sample (less than 30s)-render it a rapid and accurate methodology for toxin screening. Subsequently, an extractive electrospray ionization (EESI) mass spectrometry database was established by combining the Xcalibur data processing system with NIST database software. This allowed unknown toxicants in urine and blood samples, stomach contents, and liver samples, as provided by the Jiangxi Provincial Public Security Department, to be analyzed and identified. This EESI methodology and databank has the potential for widespread application to the large-scale analysis of practical samples. Graphical abstract ᅟ.


Assuntos
Bases de Dados Factuais , Substâncias Perigosas/análise , Ensaios de Triagem em Larga Escala/métodos , Espectrometria de Massas por Ionização por Electrospray/métodos , Toxicologia Forense , Conteúdo Gastrointestinal/química , Substâncias Perigosas/sangue , Substâncias Perigosas/urina , Humanos , Limite de Detecção , Fígado/química , Reprodutibilidade dos Testes
13.
Nanomaterials (Basel) ; 8(8)2018 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-30126156

RESUMO

Hierarchical micro-/mesoporous graphitic carbon spheres (HGCS) with a uniform diameter of ~0.35 µm were synthesized by Fe-catalyzed graphitization of amorphous carbon spheres resultant from hydrothermal carbonization. The HGCS resultant from 3 h at 900 °C with 1.0 wt % Fe catalyst had a high graphitization degree and surface area as high as 564 m²/g. They also exhibited high specific capacitance of 140 F/g at 0.2 A/g and good electrochemical stability with 94% capacitance retention after consecutive 2500 cycles. The graphitization degree of the HGCS contributed to 60% of their specific capacitance, and their specific capacitance per unit surface area was as high as 0.2 F/m², which was much higher than in the most cases of porous amorphous carbon materials reported before. In addition, the HGCS showed a high adsorption capacity of 182.8 mg/g for methylene blue (MB), which was 12 times as high as that in the case of carbon spheres before graphitization.

14.
Materials (Basel) ; 10(9)2017 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-28841188

RESUMO

The sol-gel method is a simple and facile wet chemical process for fabricating advanced materials with high homogeneity, high purity, and excellent chemical reactivity at a relatively low temperature. By adjusting the processing parameters, the sol-gel technique can be used to prepare hollow sphere and 1D structural materials that exhibit a wide application in the fields of catalyst, drug or gene carriers, photoactive, sensors and Li-ion batteries. This feature article reviewed the development of the preparation of hollow sphere and 1D structural materials using the sol-gel method. The effects of calcination temperature, soaking time, pH value, surfactant, etc., on the preparation of hollow sphere and 1D structural materials were summarized, and their formation mechanisms were generalized. Finally, possible future research directions of the sol-gel technique were outlined.

15.
Sci Rep ; 6: 31559, 2016 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-27527681

RESUMO

The catalytic effects of chromium (Cr) on the direct nitridation of silicon (Si) and morphology of nitridation product were investigated. Cr dramatically improved the conversation of Si to silicon nitride (Si3N4). The complete conversion was achieved at 1350 °C upon addition of 1.25 wt% Cr. This temperature was much lower than that required in the case without using a catalyst. Meanwhile, Cr played an important role in the in-situ growth of one-dimensional (1-D) α-Si3N4 nanostructures. α-Si3N4 nanowires and nanobelts became the primary product phases when 5 wt% Cr was used as the catalyst. The growth processes of the 1-D α-Si3N4 nanostructures were governed by the vapor-solid mechanism. First-principle calculations suggest that electrons can be transferred from Cr atoms to N atoms, facilitating the Si nitridation.

16.
Mol Immunol ; 76: 90-7, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27393910

RESUMO

Increasing evidence suggests that inflammation and apoptosis are involved in the development of acute myocardial ischemia (AMI). Nucleotide-binding oligomerization domain (NOD)-like receptors (NLRs) have recently been identified as key mediators of inflammatory responses. The aim of this study was to explore the specific role and the underlying regulatory mechanism of NLRX1 in myocardial ischemic injury. The results show that NLRX1, located in mitochondria, was significantly down-regulated in AMI tissues and hypoxia-induced H9c2 cells. Overexpression of NLRX1 markedly decreased the levels of lactate dehydrogenase (LDH), creatine kinase-MB (CK-MB) and cardiac troponin-I (cTn-I), down-regulated the production of IL-1ß,IL-18 and IL-6, and reduced apoptosis induced by hypoxia. Conversely, depletion of NLRX1 with small interfering RNA (siRNA) aggravated hypoxia-induced ischemic injury. We then demonstrated that NLRX1 was associated with the mitochondrial antiviral signaling protein (MAVS) and regulated MAVS-dependent NLRP3 inflammasome activation. NLRX1 overexpression significantly inhibited hypoxia-induced up-regulation of MAVS, NLRP3 and Caspase-1 expression. Additionally, the negative effects of NLRX1 overexpression on hypoxia-induced inflammatory factor production and apoptosis were neutralized by MAVS or NLRP3 overexpression. Taken together, these findings suggest that NLRX1 may function as a cardiac-protective molecule in myocardial ischemic injury by repressing inflammation and apoptosis; the biological effects appear to be mediated by the inhibition of MAVS-dependent NLRP3 inflammasome activation.


Assuntos
Apoptose/imunologia , Inflamassomos/imunologia , Inflamação/imunologia , Proteínas Mitocondriais/imunologia , Isquemia Miocárdica/imunologia , Proteína 3 que Contém Domínio de Pirina da Família NLR/imunologia , Proteínas Adaptadoras de Transdução de Sinal/imunologia , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Idoso , Western Blotting , Linhagem Celular , Feminino , Humanos , Imunoprecipitação , Inflamassomos/metabolismo , Inflamação/metabolismo , Masculino , Microscopia Confocal , Pessoa de Meia-Idade , Proteínas Mitocondriais/metabolismo , Isquemia Miocárdica/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Reação em Cadeia da Polimerase em Tempo Real
17.
Angew Chem Int Ed Engl ; 54(32): 9328-32, 2015 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-26089257

RESUMO

Development of highly active, low cost, ecologically friendly, and durable homogenous catalysts for hydrogen generation from hydrolysis of borohydride is one of the most desirable pathways for future hydrogen utilization. The unexpected catalytic activities of inorganic ammonium species and the corresponding mechanisms underpinning them are studied. The catalytic activities of the ammonium species are higher than or comparable to those of mostly investigated noble-metal/transition-metal catalysts (such as Pd, Pt, Ni, and Co) but are considerably cheaper, more environmentally friendly, and more readily available. Quantum chemical calculations indicate that the unique ammonium-induced reaction pathway involved with a barrierless elementary reaction at the reaction entrance and the formation of the highly active intermediate BH3 are responsible for the unexpected catalytic activities and the significantly accelerated hydrogen generation.

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