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1.
Environ Sci Pollut Res Int ; 30(47): 103776-103787, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37695486

RESUMO

In the face of intensifying climate change-induced environmental problems, understanding the causal relationship between carbon dioxide (CO2) emissions and socioeconomic factors is crucial for achieving sustainable development. This study investigates how the causal relationships between renewable energy, information and communication technology (ICT), logistics networks, economic growth, industrialization, and energy intensity impact sustainable development using a panel dataset drawn from 104 countries and covering 2006 to 2019. Methodologically, panel unit root, panel co-integration, and Granger causality tests are employed as robust econometric techniques. The results of the panel unit root and co-integration tests confirm the stationarity of the variables and reveal significant long-term relationships among them throughout the empirical analysis period. Notably, the panel FMOLS and DOLS estimates indicate a positive effect of RE and ICT on reducing CO2 emissions, whereas GDP and energy intensity have a negative impact on CO2 emissions reduction. Moreover, the pairwise Granger causality test findings indicate bidirectional causal relationships between RE and CO2, IND and CO2, ICT and RE, IND and RE, GDP and ICT, as well as IND and ICT. The study recommends providing policy support, including for technological development and innovation, towards establishing a system that fosters sustainable development.


Assuntos
Dióxido de Carbono , Comunicação , Tecnologia da Informação , Desenvolvimento Econômico , Energia Renovável , Tecnologia
2.
Anal Chem ; 94(43): 14869-14877, 2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-36265183

RESUMO

Reactive oxygen species (ROS) are endogenously generated in live cells and essential for cell signaling. However, excess ROS generation can cause oxidative damage to biomolecules, which are implicated in various human diseases, including aging. Here, we developed an in vivo hydrogen peroxide monitoring method using a genetically encodable peroxidase (APEX2)-based system. We confirmed that APEX2 is activated by endogenous H2O2 and generates phenoxyl radicals to produce biotinylated signals (i.e., biotin-phenol) and fluorescent signals (i.e., AmplexRed), which can be detected using a fluorescence microscope. We observed that all subcellular targeted APEX2s were activated by local H2O2 generation by menadione treatment. Among them, the endoplasmic reticulum lumen and lysosome-targeted APEX2 showed the highest response upon addition of menadione which implies that local H2O2 levels in those spaces are highly increased by menadione treatment. Using APEX2, we also found that a minimum amount of menadione (>10 µM) is required to generate detectable levels of H2O2 in all subcellular compartments. We also checked the local H2O2-quenching effect of N-acetylcysteine using our system. As APEX2 can be genetically expressed in diverse live organisms (e.g., cancer cell lines, mice, fly, worm, and yeast), our method can be effectively used to detect local generation of endogenously produced H2O2 in diverse live models.


Assuntos
Peróxido de Hidrogênio , Vitamina K 3 , Animais , Camundongos , Humanos , Peróxido de Hidrogênio/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Vitamina K 3/farmacologia , Estresse Oxidativo , Fenol
3.
Transportation (Amst) ; : 1-27, 2022 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-36033421

RESUMO

This study investigates the causal relationship between logistics efficiency and factors affecting the logistics environment, such as industrialization, urbanization, and CO2 emissions. With the expectation that logistics efficiency will contribute to economic growth and enhance country competitiveness in the near future, it is necessary to confirm the impact of each factor on different transportation modes, such as maritime and air transport. To this end, this study identifies causal relationships between the factors affecting the logistics environment and specific modes of transportation using data from 2010 to 2018. We employed the panel unit root test, panel co-integration test, fully modified OLS (FMOLS), panel dynamic OLS (DOLS), and panel VECM Granger causality tests for the estimations. The results revealed that factors affecting the logistics environment have different effects depending on the modes of transportation. For maritime transportation, long-run bidirectional causal associations were found between port volume, total exports, industrialization, and urbanization. This implies that export promotion and the resulting economic and social environment changes can increase port throughput; this increase can, in turn, develop and improve economic growth and factors affecting the logistics environment. In contrast, for air transport, we detected a long-run, unidirectional causal relationship among these variables and air volume changes with growing exports, urbanization, and industrialization. Thus, this study suggests a theoretical framework for analyzing the causal relationship between the factors affecting the logistics environment and each mode of transportation, providing insights for policymakers to promote logistics efficiency.

4.
J Korean Med Sci ; 32(10): 1616-1625, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28875605

RESUMO

Effective clearance of inflammatory cells is required for resolution of inflammation. Here, we show in vivo evidence that apoptosis and reverse transendothelial migration (rTEM) are important mechanisms in eliminating neutrophils and facilitating recovery following ischemia/reperfusion injury (IRI) of the kidney. The clearance of neutrophils was delayed in the Bax knockout (KO)(BM) → wild-type (WT) chimera in which bone marrow derived cells are partially resistant to apoptosis, compared to WT(BM) → WT mice. These mice also showed delayed functional, histological recovery, increased tissue cytokines, and accelerated fibrosis. The circulating intercellular adhesion molecule-1 (ICAM-1)⁺ Gr-1⁺ neutrophils displaying rTEM phenotype increased during the recovery phase and blockade of junctional adhesion molecule-C (JAM-C), a negative regulator of rTEM, resulted in an increase in circulating ICAM-1⁺ neutrophils, faster resolution of inflammation and recovery. The presence of Tamm-Horsfall protein (THP) in circulating ICAM-1⁺ neutrophils could suggest that they are derived from injured kidneys. In conclusion, we suggest that apoptosis and rTEM are critically involved in the clearance mechanisms of neutrophils during the recovery phase of IRI.


Assuntos
Injúria Renal Aguda/patologia , Neutrófilos/metabolismo , Traumatismo por Reperfusão/patologia , Injúria Renal Aguda/etiologia , Injúria Renal Aguda/imunologia , Animais , Apoptose/efeitos dos fármacos , Quimiocinas/análise , Citocinas/análise , Ensaio de Imunoadsorção Enzimática , Peróxido de Hidrogênio/toxicidade , Imunoensaio , Molécula 1 de Adesão Intercelular/sangue , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neutrófilos/citologia , Neutrófilos/imunologia , Traumatismo por Reperfusão/complicações , Baço/citologia , Baço/efeitos dos fármacos , Baço/metabolismo , Uromodulina/análise , Uromodulina/metabolismo , Proteína X Associada a bcl-2/deficiência , Proteína X Associada a bcl-2/genética
5.
Toxicol Lett ; 137(3): 143-50, 2003 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-12523956

RESUMO

The aim of this work was to identify the form(s) of human liver cytochrome P450 (CYP) involved in the hepatic transformation of myristicin to its major metabolite, 5-allyl-1-methoxy-2,3-dihydroxybenzene. When microsomes prepared from different human liver samples were compared, the activity of 5-allyl-1-methoxy-2,3-dihydroxybenzene formation was well correlated (r(2)=0.87) with nifedipine oxidation (a marker of CYP3A4). With a microsomal sample having high CYP3A4 activity, microsomal oxidation of myristicin to the major metabolite (5-allyl-1-methoxy-2,3-dihydroxybenzene) was markedly inhibited by gestodene and ketoconazole, selective inhibitors of CYP3A enzymes, but not by any of several other P450 inhibitors. Antibodies raised against CYPs 3A4 and 1A2 could also inhibit the oxidation of myristicin, but antibodies recognizing other CYPs had no effect. The oxidation of myristicin to 5-allyl-1-methoxy-2,3-dihydroxybenzene was catalyzed by purified bacterial recombinant CYPs 3A4 and 1A2. These results provide evidence that CYP3A4 (and possibly other CYP3A enzymes) and CYP1A2 play roles in the formation of the major metabolite, 5-allyl-1-methoxy-2,3-dihydroxybenzene.


Assuntos
Compostos de Benzil , Citocromo P-450 CYP1A2/metabolismo , Sistema Enzimático do Citocromo P-450/metabolismo , Dioxolanos/metabolismo , Fígado/enzimologia , Alcenos/metabolismo , Derivados de Alilbenzenos , Anticorpos Bloqueadores/farmacologia , Benzeno/metabolismo , Derivados de Benzeno , Inibidores do Citocromo P-450 CYP1A2 , Citocromo P-450 CYP3A , Inibidores das Enzimas do Citocromo P-450 , Inibidores Enzimáticos/farmacologia , Escherichia coli/efeitos dos fármacos , Escherichia coli/enzimologia , Humanos , Técnicas In Vitro , Cetoconazol/farmacologia , Fígado/efeitos dos fármacos , Microssomos Hepáticos/efeitos dos fármacos , Microssomos Hepáticos/enzimologia , Norpregnenos/farmacologia , Oxirredução , Pirogalol/análogos & derivados
6.
Biomed Chromatogr ; 16(6): 395-9, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12228896

RESUMO

The in vitro metabolism of a new erectogenic, DA-8159, has been studied by LC with UV detection and on-line LC-electrospray mass spectrometry using rat hepatic microsomal incubation and rat liver perfusion. Both rat liver microsomal incubation of DA-8159 in the presence of NADPH and single-pass liver perfusion of DA-8159 resulted in the formation of three metabolites (M1-3). M1 was tentatively identified as hydroxy-DA-8159. M2 and M3 were identified as N-demethyl-DA-8159 and 5-(2-propyloxy-5-aminosulphonylphenyl)-1-methyl-3-propyl-1,6-dihydro-7H-pyrazolo(4,3-d)pyrimidin-7-one (DA-8164), respectively, on the basis of LC-MS/MS analysis with authentic standards. Rat CYP2D1 was a major isozyme for the formation of hydroxy-DA-8159 and N-demethyl-DA-8159. CYP2C12 and CYP1A1 catalysed the oxidation of DA-8159 to DA-8164.


Assuntos
Cromatografia Líquida/métodos , Microssomos Hepáticos/metabolismo , Inibidores de Fosfodiesterase/metabolismo , Inibidores de Fosfodiesterase/farmacocinética , Diester Fosfórico Hidrolases/efeitos dos fármacos , Pirimidinas , Espectrometria de Massas por Ionização por Electrospray/métodos , 3',5'-GMP Cíclico Fosfodiesterases , Animais , Nucleotídeo Cíclico Fosfodiesterase do Tipo 5 , Sistema Enzimático do Citocromo P-450/metabolismo , Masculino , Microssomos Hepáticos/enzimologia , Ratos , Ratos Sprague-Dawley , Padrões de Referência , Sulfonamidas
7.
J Pharm Biomed Anal ; 28(5): 897-902, 2002 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-12039631

RESUMO

The metabolism of a new H+/K+ ATPase inhibitor, KR-60436 [1-(4-methoxy-2-methyl-phenyl)-4-[(2-hydroxyethyl)amino]-6-trifluoromethoxy-2,3-dihydropyrrolo[3,2-c]quinoline] has been studied by LC-electrospray mass spectrometry. In vitro incubation of KR-60436 with rat and human liver microsomes in the presence of NADPH produced seven metabolites (M1-M7). M3-M6 were identified as O-demethyl-KR-60436, O-demethyl-pyrrole-KR-60436, N-dehydroxyethyl-KR-60436 and pyrrole-KR-60436, respectively, based on LC/MS/MS analysis with authentic standards. M1, M2 and M7 were tentatively identified as monohydroxylated-KR-60436, monohydroxylated-pyrrole-KR-60436 and N-dehydroxyethyl-pyrrole-KR-60436, respectively. The four principal metabolic pathways are characterized in KR-60436 metabolism: oxidation of dihydropyrrole ring to pyrrole, O-demethylation of methoxy group, hydroxylation of quinoline moiety and N-dealkylation of hydroxyethylamino group.


Assuntos
Inibidores Enzimáticos/farmacocinética , Microssomos Hepáticos/metabolismo , Inibidores da Bomba de Prótons , Pirróis/farmacocinética , Quinolinas/farmacocinética , Animais , Biotransformação , Cromatografia Líquida de Alta Pressão , Humanos , Técnicas In Vitro , Masculino , Pirróis/análise , Quinolinas/análise , Ratos , Espectrometria de Massas por Ionização por Electrospray
8.
Biomed Chromatogr ; 16(4): 277-81, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11933029

RESUMO

A rapid and sensitive column-switching semi-micro HPLC method is described for the direct analysis of tofisopam in human serum. The sample (100 microL) was directly injected onto the precolumn (Capcell Pak MF Ph-1), where unretained proteins were eluted to waste. Tofisopam was then eluted into an enrichment column using 13% acetonitrile in 50 mM phosphate buffer (pH 7.0) containing 5 mM sodium octanesulfonate and subsequently into the analytical column using 43% acetonitrile in 0.1% phosphoric acid containing 5 mM sodium octanesulfonate. The detection limit (2 ng/mL), good precision (CV < or = 4.2%) and speed (total analysis time 24 min) of the present method were sufficient for drug monitoring. This method was successfully applied to a bioequivalence test of two commercial tofisopam tablets.


Assuntos
Ansiolíticos/sangue , Benzodiazepinas , Cromatografia Líquida de Alta Pressão/métodos , Adulto , Ansiolíticos/farmacocinética , Avaliação Pré-Clínica de Medicamentos , Humanos , Masculino , Reprodutibilidade dos Testes
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