Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 8 de 8
Filtrar
Mais filtros

Base de dados
Tipo de documento
Intervalo de ano de publicação
1.
Chem Rev ; 124(13): 8233-8306, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38885684

RESUMO

Interest in energy-to-X and X-to-energy (where X represents green hydrogen, carbon-based fuels, or ammonia) technologies has expanded the field of electrochemical conversion and storage. Solid oxide electrochemical cells (SOCs) are among the most promising technologies for these processes. Their unmatched conversion efficiencies result from favorable thermodynamics and kinetics at elevated operating temperatures (400-900 °C). These solid-state electrochemical systems exhibit flexibility in reversible operation between fuel cell and electrolysis modes and can efficiently utilize a variety of fuels. However, electrocatalytic materials at SOC electrodes remain nonoptimal for facilitating reversible operation and fuel flexibility. In this Review, we explore the diverse range of electrocatalytic materials utilized in oxygen-ion-conducting SOCs (O-SOCs) and proton-conducting SOCs (H-SOCs). We examine their electrochemical activity as a function of composition and structure across different electrochemical reactions to highlight characteristics that lead to optimal catalytic performance. Catalyst deactivation mechanisms under different operating conditions are discussed to assess the bottlenecks in performance. We conclude by providing guidelines for evaluating the electrochemical performance of electrode catalysts in SOCs and for designing effective catalysts to achieve flexibility in fuel usage and mode of operation.

2.
Biomed Pharmacother ; 176: 116781, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38805966

RESUMO

Influenza A virus causes numerous deaths and infections worldwide annually. Therefore, we have considered nanobodies as a potential treatment for patients with severe cases of influenza. We developed a nanobody that was expected to have protective efficacy against the A/California/04/2009 (CA/04; pandemic 2009 flu strain) and evaluated its therapeutic efficacy against CA/04 in mice experiments. This nanobody was derived from the immunization of the alpaca, and the inactivated CA/04 virus was used as an immunogen. We successfully generated a nanobody library through bio-panning, phage ELISA, and Bio-layer interferometry. Moreover, we confirmed that administering nanobodies after lethal doses of CA/04 reduced viral replication in the lungs and influenza-induced clinical signs in mice. These research findings will help to develop nanobodies as viral therapeutics for CA/04 and other infectious viruses.


Assuntos
Vírus da Influenza A Subtipo H1N1 , Infecções por Orthomyxoviridae , Anticorpos de Domínio Único , Animais , Anticorpos de Domínio Único/imunologia , Vírus da Influenza A Subtipo H1N1/imunologia , Camundongos , Infecções por Orthomyxoviridae/imunologia , Infecções por Orthomyxoviridae/tratamento farmacológico , Infecções por Orthomyxoviridae/virologia , Feminino , Camundongos Endogâmicos BALB C , Camelídeos Americanos/imunologia , Pulmão/imunologia , Pulmão/virologia , Pulmão/efeitos dos fármacos , Pulmão/patologia , Anticorpos Antivirais/imunologia , Replicação Viral/efeitos dos fármacos
3.
Small ; : e2306653, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38534177

RESUMO

Increasing densities of reaction sites for gaseous reactants in solid oxide electrochemical reactors (SOERs), is a key strategy for achieving enhanced performance in either fuel cell or electrolysis modes. Fabrication of 3D structured components in SOERs can enhance those densities of reaction sites, which is achieved by 3D inkjet printing with high reproducibility, having developed inks with appropriate properties. First, the effects of pillar geometries on SOER performances are predicted through numerical simulations, enabling subsequent 3D printing to focus on the more effective geometries. Herein, the study reports the results of experimental validation of those predictions by evaluating the electrochemical performances of cells with various heights of 3D inkjet-printed Ni(O)- yttria stabilized zirconia (YSZ) pillars and YSZ pillars. Those measurements prove that increasing pillar heights generally increases SOER peak power densities in fuel cell mode and increased current densities at the thermoneutral potential (1.285 V) in steam electrolysis mode, as predicted by simulations. With increasing pillar heights, more limitations in performance enhancement are found with YSZ electrolyte pillars than with Ni-YSZ pillars, again as predicted by simulations. The subsequent microstructural analysis of Ni-YSZ pillars proves the suitability of the Ni(O)-YSZ composite particle ink formulation and the reliability of 3D printing.

4.
Artigo em Inglês | MEDLINE | ID: mdl-35162086

RESUMO

How does future anxiety caused by the COVID-19 pandemic relate to people's willingness to remain vigilant and adhere to preventive measures? We examined the mediating role of message fatigue and the moderating role of autonomy satisfaction in the relationship between future anxiety due to COVID-19 and willingness to remain vigilant. A cross-sectional online survey was conducted with adults residing in the United States in June 2021 when numerous U.S. states re-opened following the CDC's relaxed guidelines for fully vaccinated individuals. Our data showed that message fatigue mediated the relationship between future anxiety due to the pandemic and willingness to remain vigilant. The data further revealed that autonomy satisfaction significantly moderated the mediation. Namely, the role of message fatigue in the indirect relationship between future anxiety and willingness to remain vigilant was significant only among people low to moderate in autonomy satisfaction; its role in the indirect path was not significant for those high in autonomy satisfaction. Notably, independent of the mechanism involving message fatigue, future anxiety was directly and positively associated with willingness to remain vigilant regardless of the levels of autonomy satisfaction. Implications of these findings are discussed in light of psychological and behavioral responses to the current pandemic and policy directions.


Assuntos
COVID-19 , Adulto , Ansiedade/epidemiologia , Estudos Transversais , Fadiga/epidemiologia , Humanos , Pandemias , Satisfação Pessoal , SARS-CoV-2
5.
BMC Cancer ; 16: 35, 2016 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-26801760

RESUMO

BACKGROUND: c-Met signaling has been implicated in oncogenesis especially in cells with c-met gene amplification. Since 20 % of gastric cancer patients show high level of c-Met expression, c-Met has been identified as a good candidate for targeted therapy in gastric cancer. Herein, we report our newly synthesized c-Met inhibitor by showing its efficacy both in vitro and in vivo. METHODS: Compounds with both triazolopyrazine and pyridoxazine scaffolds were synthesized and tested using HTRF c-Met kinase assay. We performed cytotoxic assay, cellular phosphorylation assay, and cell cycle assay to investigate the cellular inhibitory mechanism of our compounds. We also conducted mouse xenograft assay to see efficacy in vivo. RESULTS: KRC-00509 and KRC-00715 were selected as excellent c-Met inhibitors through biochemical assay, and exhibited to be exclusively selective to c-Met by kinase panel assay. Cytotoxic assays using 18 gastric cancer cell lines showed our c-Met inhibitors suppressed specifically the growth of c-Met overexpressed cell lines, not that of c-Met low expressed cell lines, by inducing G1/S arrest. In c-met amplified cell lines, c-Met inhibitors reduced the downstream signals including Akt and Erk as well as c-Met activity. In vivo Hs746T xenograft assay showed KRC-00715 reduced the tumor size significantly. CONCLUSIONS: Our in vitro and in vivo data suggest KRC-00715 is a potent and highly selective c-Met inhibitor which may have therapeutic potential in gastric tumor with c-Met overexpression.


Assuntos
Proliferação de Células/efeitos dos fármacos , Inibidores de Proteínas Quinases/administração & dosagem , Proteínas Proto-Oncogênicas c-met/biossíntese , Pirazinas/administração & dosagem , Neoplasias Gástricas/tratamento farmacológico , Triazóis/administração & dosagem , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/síntese química , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Camundongos , Inibidores de Proteínas Quinases/síntese química , Proteínas Proto-Oncogênicas c-met/genética , Pirazinas/síntese química , Transdução de Sinais/efeitos dos fármacos , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologia , Triazóis/síntese química , Ensaios Antitumorais Modelo de Xenoenxerto
6.
Environ Geochem Health ; 37(6): 1007-15, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26123992

RESUMO

Methane, which is produced by methanogenic archaea, is the second most abundant carbon compound in the atmosphere. Due to its strong radiative forcing, many studies have been conducted to determine its sources, budget, and dynamics. However, a mechanistic model of methane flux has not been developed thus far. In this study, we attempt to examine the relevance of the abundance of methanogen as a biological indicator of methane flux in three different types of soil ecosystems: permafrost, rice paddy, and mountainous wetland. We measured the annual average methane flux and abundance of methanogen in the soil ecosystems in situ. The correlation between methane flux and the abundance of methanogen exists only under a specific biogeochemical conditions such as SOM of higher than 60%, pH of 5.6-6.4, and water-saturated. Except for these conditions, significant correlations were absent. Therefore, microbial abundance information can be applied to a methane flux model selectively depending on the biogeochemical properties of the soil ecosystem.


Assuntos
Archaea/isolamento & purificação , Metano/metabolismo , Microbiologia do Solo , Solo/química , Archaea/metabolismo , Ecossistema , Concentração de Íons de Hidrogênio , Metano/química , Pergelissolo/química , Pergelissolo/microbiologia , Áreas Alagadas
7.
Bioorg Med Chem Lett ; 23(22): 6192-6, 2013 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-24095090

RESUMO

The synthesis of bis-ortho-alkoxy-para-piperazinesubstituted-2,4-dianilinopyrimidines is described and their structure-activity-relationship to anaplastic lymphoma kinase (ALK) is presented. KRCA-0008 is selective and potent to ALK and Ack1, and displays drug-like properties without hERG liability. KRCA-0008 demonstrates in vivo efficacy comparable to Crizotinib in xenograft mice model.


Assuntos
Piperazinas/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Pirimidinas/farmacologia , Receptores Proteína Tirosina Quinases/antagonistas & inibidores , Quinase do Linfoma Anaplásico , Animais , Linhagem Celular Tumoral , Crizotinibe , Modelos Animais de Doenças , Neoplasias Pulmonares/tratamento farmacológico , Camundongos , Piperazinas/química , Piperazinas/farmacocinética , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/farmacocinética , Pirazóis/farmacologia , Piridinas/farmacologia , Pirimidinas/química , Pirimidinas/farmacocinética , Relação Estrutura-Atividade , Ensaios Antitumorais Modelo de Xenoenxerto
8.
Microb Ecol ; 65(2): 405-14, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22983497

RESUMO

Tundra ecosystem is of importance for its high accumulation of organic carbon and vulnerability to future climate change. Microorganisms play a key role in carbon dynamics of the tundra ecosystem by mineralizing organic carbon. We assessed both ecosystem process rates and community structure of Bacteria, Archaea, and Fungi in different soil layers (surface organic layer and subsurface mineral soil) in an Arctic soil ecosystem located at Spitsbergen, Svalbard during the summer of 2008 by using biochemical and molecular analyses, such as enzymatic assay, terminal restriction fragment length polymorphism (T-RFLP), quantitative polymerase chain reaction (qPCR), and pyrosequencing. Activity of hydrolytic enzymes showed difference according to soil type. For all three microbial communities, the average gene copy number did not significantly differ between soil types. However, archaeal diversities appeared to differ according to soil type, whereas bacterial and fungal diversity indices did not show any variation. Correlation analysis between biogeochemical and microbial parameters exhibited a discriminating pattern according to microbial or soil types. Analysis of the microbial community structure showed that bacterial and archaeal communities have different profiles with unique phylotypes in terms of soil types. Water content and hydrolytic enzymes were found to be related with the structure of bacterial and archaeal communities, whereas soil organic matter (SOM) and total organic carbon (TOC) were related with bacterial communities. The overall results of this study indicate that microbial enzyme activity were generally higher in the organic layer than in mineral soils and that bacterial and archaeal communities differed between the organic layer and mineral soils in the Arctic region. Compared to mineral soil, peat-covered organic layer may represent a hotspot for secondary productivity and nutrient cycling in this ecosystem.


Assuntos
Biodiversidade , Ecossistema , Microbiologia do Solo , Archaea/genética , Regiões Árticas , Bactérias/genética , Carbono/análise , DNA Arqueal/análise , DNA Bacteriano/análise , DNA Fúngico/análise , Fungos/genética , Análise Multivariada , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Solo/análise , Svalbard
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA