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1.
Fish Shellfish Immunol ; 150: 109662, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38821229

RESUMO

SIRT6, a key member of the sirtuin family, plays a pivotal role in regulating a number of vital biological processes, including energy metabolism, oxidative stress, and immune system modulation. Nevertheless, the function of SIRT6 in bony fish, particularly in the context of antiviral immune response, remains largely unexplored. In this study, a sirt6 was cloned and characterized in a commercial fish, the Chinese perch (Siniperca chuatsi). The SIRT6 possesses conserved SIR2 domain with catalytic core region when compared with other vertebrates. Tissue distribution analysis indicated that sirt6 was expressed in all detected tissues, and the sirt6 was significantly induced following infection of infectious haemorrhagic syndrome virus (IHSV). The overexpression of SIRT6 resulted in significant upregulation of interferon-stimulated genes (ISGs), such as viperin, mx, isg15, irf3 and ifp35, and inhibited viral replication. It was further found that SIRT6 was located in nucleus and could enhance the expression of ISGs induced by type I and II IFNs. These findings may provide new information in relation with the function of SIRT6 in vertebrates, and with viral prevention strategy development in aquaculture.


Assuntos
Sequência de Aminoácidos , Doenças dos Peixes , Proteínas de Peixes , Regulação da Expressão Gênica , Imunidade Inata , Percas , Filogenia , Infecções por Rhabdoviridae , Sirtuínas , Animais , Sirtuínas/genética , Sirtuínas/imunologia , Sirtuínas/metabolismo , Doenças dos Peixes/imunologia , Doenças dos Peixes/virologia , Proteínas de Peixes/genética , Proteínas de Peixes/imunologia , Proteínas de Peixes/química , Imunidade Inata/genética , Infecções por Rhabdoviridae/imunologia , Infecções por Rhabdoviridae/veterinária , Regulação da Expressão Gênica/imunologia , Percas/imunologia , Alinhamento de Sequência/veterinária , Perfilação da Expressão Gênica/veterinária
2.
J Sci Food Agric ; 102(6): 2526-2537, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34676564

RESUMO

BACKGROUND: Selenium (Se)-enriched glycoproteins have been a research highlight for the role of both Se and glycoproteins in immunoregulation. Arsenic (As) is a toxicant that is potentially toxic to the immune function and consequently to human health. Several reports suggested that Se could reduce the toxicity of heavy metals. Moreover, more and more nutrients in food had been applied to relieve As-induced toxicity. Hence glycoproteins were isolated and purified from Se-enriched Grifola frondosa, and their preliminary characteristics as well as amelioration effect and mechanism on As3+ -induced immune toxicity were evaluated. RESULTS: Four factions, namely Se-GPr11 (electrophoresis analysis exhibited one band: 14.32 kDa), Se-GPr22 (two bands: 20.57 and 31.12 kDa), Se-GPr33 (three bands: 15.08, 20.57 and 32.78 kDa) and Se-GPr44 (three bands: 16.73, 32.78 and 42.46 kDa), were obtained from Se-enriched G. frondosa via DEAE-52 and Sephacryl S-400 column. In addition, Se-GPr11 and Se-GPr44 are ideal proteins that contain high amounts of almost all essential amino acids. Thereafter, the RAW264.7 macrophage model was adopted to estimate the effect of Se-GPr11 and Se-GPr44 on As3+ -induced immune toxicity. The results showed that the pre-intervention method was the best consequent and the potential mechanisms were, first, by improving the oxidative stress state (enhancing the activity of superoxide dismutase and glutathione peroxidase, decreasing the levels of reactive oxygen species and malondialdehyde); secondly, through nuclear factor-κB and mitogen-activated protein kinase-mediated upregulation cytokines (interleukin-2 and interferon-γ) secretion induced by As3+ . CONCLUSION: The results suggested Se-enriched G. frondosa may be a feasible supplement to improve health level of the As3+ pollution population. © 2021 Society of Chemical Industry.


Assuntos
Arsênio , Grifola , Selênio , Glutationa Peroxidase/metabolismo , Glicoproteínas/farmacologia , Grifola/química , Grifola/metabolismo , Humanos , Selênio/metabolismo
3.
Water Sci Technol ; 70(10): 1663-9, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25429455

RESUMO

Triphenylmethane (TPM) dye is one of the most prevalent and recalcitrant water contaminants. Magnetic reduced graphene oxide (rGO) is an efficient adsorbent for organic pollutants removal. However, the performance and adsorption kinetics of magnetic rGO towards TPM have not yet been studied. In this study, a magnetic Fe3O4@rGO nano-composite, which could be easily removed from water with a simple magnetic separation step was synthesized and characterized. The magnetic rGO showed fast adsorption rate and high adsorption capacity towards different TPM dyes (the Langmuir monolayer adsorption capacity is 64.93 mg/g for adsorption of crystal violet). The adsorption processes are well-fitted to the pseudo-second-order kinetic model (R(2) > 0.99) and the Langmuir isotherm model (R(2) = 0.9996). Moreover, the magnetic rGO also showed excellent recycling and regeneration capabilities. The results indicated that adsorption with magnetic rGO would be a promising strategy to clean up the TPM contamination.


Assuntos
Corantes/química , Compostos Férricos/química , Grafite/química , Nanocompostos/química , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/química , Adsorção , Cinética , Compostos de Tritil/química
4.
Front Immunol ; 15: 1374368, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38715616

RESUMO

NOD1 and NOD2 as two representative members of nucleotide-binding oligomerization domain (NOD)-like receptor (NLR) family play important roles in antimicrobial immunity. However, transcription mechanism of nod1 and nod2 and their signal circle are less understood in teleost fish. In this study, with the cloning of card9 and ripk2 in Chinese perch, the interaction between NOD1, NOD2, and CARD9 and RIPK2 were revealed through coimmunoprecipitation and immunofluorescence assays. The overexpression of NOD1, NOD2, RIPK2 and CARD9 induced significantly the promoter activity of NF-κB, IFNh and IFNc. Furthermore, it was found that nod1 and nod2 were induced by poly(I:C), type I IFNs, RLR and even NOD1/NOD2 themselves through the ISRE site of their proximal promoters. It is thus indicated that nod1 and nod2 can be classified also as ISGs due to the presence of ISRE in their proximal promoter, and their expression can be mechanistically controlled through PRR pathway as well as through IFN signaling in antiviral immune response.


Assuntos
Proteínas de Peixes , Proteína Adaptadora de Sinalização NOD1 , Proteína Adaptadora de Sinalização NOD2 , Proteína Serina-Treonina Quinase 2 de Interação com Receptor , Transdução de Sinais , Animais , Proteína Adaptadora de Sinalização NOD1/genética , Proteína Adaptadora de Sinalização NOD1/metabolismo , Proteína Serina-Treonina Quinase 2 de Interação com Receptor/metabolismo , Proteína Serina-Treonina Quinase 2 de Interação com Receptor/genética , Proteína Adaptadora de Sinalização NOD2/genética , Proteína Adaptadora de Sinalização NOD2/metabolismo , Proteínas de Peixes/genética , Proteínas de Peixes/metabolismo , Proteínas de Peixes/imunologia , Percas/genética , Percas/imunologia , Percas/metabolismo , Interferons/metabolismo , Interferons/genética , Regiões Promotoras Genéticas , Transcrição Gênica , Imunidade Inata/genética , Ligação Proteica
5.
Bioorg Med Chem Lett ; 23(20): 5748-51, 2013 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-23999045

RESUMO

Five new degraded diterpenoids trigoxyphins J-N (1-5), among them trigoxyphins K and L have a novel carbon skeleton, together with four known analogues (6-9) have been obtained from the ethanol extract of the twigs of Trigonostemon xyphophylloides. Compounds 1-5 were evaluated for their cytotoxic activity in vitro against three human tumor cell lines by MTT assay. The results exhibited that Trigoxyphin N (5) showed moderate cytotoxicities against SPC-A-1 and SGC-7901 cancer cell lines.


Assuntos
Antineoplásicos Fitogênicos/química , Diterpenos/química , Euphorbiaceae/química , Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/toxicidade , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Diterpenos/isolamento & purificação , Diterpenos/toxicidade , Euphorbiaceae/metabolismo , Humanos , Espectroscopia de Ressonância Magnética , Conformação Molecular , Extratos Vegetais/química , Relação Estrutura-Atividade
6.
Bioorg Med Chem Lett ; 22(11): 3828-30, 2012 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-22572582

RESUMO

Two new daphnane diterpenoids (1 and 2), together with four known analogues (3-6) were isolated from Trigonostemon xyphophylloides. Their structures were elucidated by spectroscopic analysis. Compounds 1 and 2 were evaluated for in vitro cytotoxic activities against the SPCA-1 (human lung cancer) and BEL-7402 (human hepatocellular carcinoma) cancer cell lines. Trigoxyphin I (2) showed modest cytotoxicity against two tumor cell lines.


Assuntos
Antineoplásicos Fitogênicos/química , Diterpenos/química , Euphorbiaceae/química , Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/toxicidade , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Diterpenos/isolamento & purificação , Diterpenos/toxicidade , Humanos , Espectroscopia de Ressonância Magnética , Conformação Molecular
7.
Front Immunol ; 13: 879775, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36090984

RESUMO

Arabinogalactan (AG) participates in forming the cell wall core of mycobacteria, a structure known as the mAGP complex. Few studies have reported the virulence of inartificial AG or its interaction with the host immune system. Using clustered regularly interspaced short palindromic repeats interference gene editing technology, conditional Mycobacterium marinum mutants were constructed with a low expression of embA or glfT2 (EmbA_KD or GlfT2_KD), which are separately involved in the biosynthesis of AG arabinose and galactose domains. High-performance gel permeation chromatography and high-performance liquid chromatography assays confirmed that the EmbA_KD strain showed a remarkable decrease in AG content with fragmentary arabinose chains, and the GlfT2_KD strain displayed less reduction in content with cut-down galactose chains. Based on transmission and scanning electron microscopy observations, the cell walls of the two mutants were found to be dramatically thickened, and the boundaries of different layers were more distinct. Phenotypes including the over-secretion of extracellular substances and enhanced spreading motility with a concomitant decreased resistance to ethambutol appeared in the EmbA_KD strain. The EmbA_KD and GlfT2_KD strains displayed limited intracellular proliferation after infecting murine J774A.1 macrophages. The disease progression infected with the EmbA_KD or GlfT2_KD strain significantly slowed down in zebrafish/murine tail infection models as well. Through transcriptome profiling, macrophages infected by EmbA_KD/GlfT2_KD strains showed enhanced oxidative metabolism. The cell survival measured using the CCK8 assay of macrophages exposed to the EmbA_KD strain was upregulated and consistent with the pathway enrichment analysis of differentially expressed genes in terms of cell cycle/apoptosis. The overexpression of C/EBPß and the increasing secretion of proinflammatory cytokines were validated in the macrophages infected by the EmbA_KD mutant. In conclusion, the AG of Mycobacterium appears to restrain the host innate immune responses to enhance intracellular proliferation by interfering with oxidative metabolism and causing macrophage death. The arabinose chains of AG influence the Mycobacterium virulence and pathogenicity to a greater extent.


Assuntos
Mycobacterium marinum , Animais , Arabinose , Galactanos , Galactose , Imunidade Inata , Camundongos , Virulência , Peixe-Zebra
8.
J Sep Sci ; 34(14): 1746-53, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21674792

RESUMO

The novel surface imprinted polymer composites (MIP/K(2)Ti(4)O(9)) were prepared using dibenzothiophene (DBT) as the template, 4-vinylpyridine as the functional monomer and potassium tetratitanate whisker (K(2)Ti(4)O(9)) as the carrier. The synthetic product was characterized by Fourier transform infrared spectroscopy and scanning electron microscopy. Parameters influencing DBT adsorption such as contact time, temperature and DBT initial concentration were investigated. The adsorption kinetics were evaluated with the pseudo-first-order and pseudo-second-order models, and the adsorption isotherms were fitted by Langmuir and Freundlich models. Selectivity experiments showed that MIP/K(2)Ti(4)O(9) exhibited excellent recognition capacity and binding affinity to DBT compared with the comparative substrates. MIP/K(2)Ti(4)O(9) could also be easily regenerated and reused ten times with only about 20% loss of adsorption capacity.


Assuntos
Poluentes Ambientais/isolamento & purificação , Polímeros/química , Extração em Fase Sólida/instrumentação , Tiofenos/isolamento & purificação , Adsorção , Poluentes Ambientais/química , Cinética , Impressão Molecular , Polímeros/síntese química , Extração em Fase Sólida/métodos , Ácido Tetratiônico/química , Tiofenos/química
9.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 2): o474, 2011 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-21523132

RESUMO

In the crystal structure of the title 1:1 adduct, C(12)H(8)N(2)·C(14)H(6)O(7), the carboxyl groups are involved in inter-molecular O-H⋯O hydrogen bonds, which link the mol-ecules into centrosymmetric dimers. These dimers are further linked by inter-molecular O-H⋯N hydrogen bonds. C-H⋯O inter-actions also occur between the 1,10-phenanthroline (phen) and 4,5-dicarb-oxy-naphthalene-1,8-dicarb-oxy-lic anhydride (H(2)NTC) mol-ecules. In addition, the crystal structure exhibits π-π inter-actions of the phen⋯phen and H(2)NTC⋯H(2)NTC types with centroid-centroid distances of 3.579 (3) and 3.774 (3) Å, respectively.

10.
Zhongguo Yi Liao Qi Xie Za Zhi ; 35(3): 229-30, 2011 May.
Artigo em Chinês | MEDLINE | ID: mdl-21954586

RESUMO

Based on the practice of workflow, information management system about medical equipment was developed and its functions such as gathering, browsing, inquiring and counting were introduced. With dynamic and complete case management of medical equipment, the system improved the management of medical equipment.


Assuntos
Equipamentos e Provisões , Sistemas de Informação Administrativa , Gestão da Informação
11.
Anal Chem ; 82(8): 3108-13, 2010 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-20334436

RESUMO

This letter described the design and synthesis of a novel fluorescein-appended rhodamine spirolactam derivative and its preliminary application as a ratiometric fluorescent cellular imaging probe for Zn(2+). The ratiometric fluorescent signal change of the probe is based on an intramolecular fluorescence resonance energy transfer (FRET) mechanism modulated by a specific metal ion induced ring-opening process of the rhodamine spirolactam (acting as a trigger). In the new developed sensing system, the emission peaks of the two fluorophores are well-resolved, which can avoid the emission spectra overlap problem generally met by spectra-shift type probes and benefits for observation of fluorescence signal change at two different emission wavelengths with high resolution. It also benefits for a large range of emission ratios, thereby a high sensitivity for Zn(2+)detection. Under optimized experimental conditions, the probe exhibits a stable response for Zn(2+) over a concentration range from 2.0 x 10(-7) to 2.0 x 10(-5) M, with a detection limit of 4.0 x 10(-8) M. Most importantly, the novel probe has well solved the problem of serious interferences from other transition metal ions generally met by previously reported typical fluorescent probes for Zn(2+) with the di(2-picolyl)amine moiety as the receptor (in this case, the fluorescence response induced by Cd(2+)is even comparable to that of Zn(2+)) and shows a reversible and fast response toward Zn(2+). All these unique features make it particularly favorable for ratiometric cellular imaging investigations. It has been preliminarily used for ratiometric imaging of Zn(2+) in living cells with satisfying resolution.


Assuntos
Transferência Ressonante de Energia de Fluorescência/métodos , Corantes Fluorescentes/química , Lactamas/química , Rodaminas/química , Zinco/química , Células HeLa , Humanos , Microscopia de Fluorescência
12.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 11): o2973-4, 2010 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-21589140

RESUMO

There are two independent mol-ecules in the asymmetric unit of the title compound, C(30)H(21)ClN(2)O, which differ slightly in the orientation of the unsubstituted phenyl ring. Inter-molecular C-H⋯π inter-actions stabilize the crystal structure. The crystal studied was found to be a racemic twin. The dihedral angles between the substituted phenyl ring and the benzo[c]phenanthridine system are 87.13 (5) and 79.25 (5)° in the two molecules.

13.
Huan Jing Ke Xue ; 41(3): 1265-1275, 2020 Mar 08.
Artigo em Chinês | MEDLINE | ID: mdl-32608628

RESUMO

To explore the water purification efficiency and phytoplankton control efficiency of the water source ecological purification system, and evaluate the effectiveness of the functional group (FG) and morphology-based functional group (MBFG) in response to the internal environment and water quality of the water source ecological purification system, in the summer of 2018, the water quality and phytoplankton functional groups of each unit of the Yanlong Lake ecological purification system were monitored and analyzed. The results showed that the Yanlong Lake water source ecological purification system can effectively purify the water. The average values of total phosphorus, total nitrogen, dissolved oxygen, and turbidity in the influent water were 0.20 mg·L-1, 1.91 mg·L-1, 2.88 mg·L-1, and 60.23 NTU, respectively; after system treatment, these were 0.09 mg·L-1, 0.95 mg·L-1, 6.26 mg·L-1, and 39.53 NTU, respectively. Simultaneously, the spatial distribution of water quality within the system was heterogeneous, with significant spatial differences in dissolved oxygen (DO), pH, and turbidity (P<0.001). The Yanlong Lake water source ecological purification system could effectively control the density of phytoplankton (4.42×105-4.32×106 cells·L-1) when the effluent was in a mild eutrophication state. This reduced the risk of algal blooms. There were five absolute advantage FG:B, P, TC, J, and W1. There were six absolute advantage MBFG:GroupⅠ, GroupⅢ, GroupⅣ, GroupⅤ, GroupⅥ, and GroupⅦ. Both absolute dominant functional groups were effective in indicating changes in habitat conditions. The results of RDA analysis found that the environmental interpretation of the MBFG was higher than that of the FG. The results suggested that it is more appropriate to study the dynamics of phytoplankton in the Yanlong Lake ecological purification system in summer by selecting the MBFG classification method.

15.
Huan Jing Ke Xue ; 40(4): 1742-1750, 2019 Apr 08.
Artigo em Chinês | MEDLINE | ID: mdl-31087915

RESUMO

An investigation the optical properties and spatial distribution of dissolved organic matter (DOM) in an ecological purification system and the primary factors that affect the optical properties of the DOM was conducted. Taking the Yanlong Lake ecological purification system as an example, data from spring 2017 and 2018 were compared. The results show that the concentrations of total phosphorus and total nitrogen and the permanganate index in Yanlong Lake were 0.05-0.25, 1.25-2.75, and 3.99-7.17 mg·L-1, respectively. In addition, the dissolved oxygen in the effluent of Yanlong Lake increased to (11.93±1.31) mg·L-1, and the turbidity decreased to (13.23±2.24) NTU, while the change in the permanganate index was not significant. Principal component analysis (PCA) showed that the water quality of the Yanlong Lake raw water and water in the pre-treatment area was closely related to the inflow of exogenous sources, while the water quality in submerged plant areas and deep purification areas was dependent on endogenous effects. According to the fluorescence index, humification index, and biological source index analysis, it was found that there are new spontaneous sources of DOM in this body of water, the degree of humification is lower, and endogenous biological DOM is dominant. The PARAFAC model can be used to classify DOM into UV-fulvic acid-like components (239 nm, 304 nm/407 nm), visible light fulvic acid-like components (256 nm, 352 nm/439 nm), tryptophan-like protein (276 nm/327 nm) and humic acid (292 nm, 395 nm/491 nm). The UV absorption index indicates that the spectral intensity of DOM in the raw water, pretreatment unit, and emergent water plant area of Yanlong Lake fluctuates greatly, and the DOM spectral intensity of the submerged plant area and deep purification area is relatively stable. The factors affecting the optical properties of the DOM in terms of water quality parameters are mainly transparency, dissolved oxygen, conductivity, total nitrogen, and algae cell number.

16.
Food Chem Toxicol ; 134: 110803, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31563530

RESUMO

Polychlorinated biphenyls (PCBs) would do serious damage to multiple systems, while coplanar polychlorinated biphenyls, the most toxic member of the family, has been widely taken into consideration. In this study, ICR mice were fed with different doses of PCB126 to explore the underlying molecular mechanisms on immunotoxicity. The results showed that PCB126 caused immunosuppression as evidenced by inhibiting the ratios of thymus and spleen weights, changing the organizational structure and decreasing levels and mRNA expression of TNF-α, IFN-γ and IL-2. PCB126 inhibited the SOD activity and spurred the accumulation of MDA in spleen and thymus. Meanwhile, it also disturbed the Nrf2 signaling pathway as evidenced by up-regulating the mRNA expression of Nrf2 and Keap1. Additionally, a remarkable reduction in the mRNA expression of AhR and enhancement in the mRNA expression of Cyp1 enzymes (Cyp1a1, Cyp1a2 and Cyp1b1) were observed, which increased the ROS levels. PCB126 could increase protein expression of Bax, Caspase-3, Caspase-8 and Caspase-9, while the protein expression of Bcl-2 was decreased. In summary, the results indicated that PCB126 modulated the AhR signaling pathway, which interacted with apoptosis and oxidative stress to induce immunotoxicity, enrich the immunotoxicological mechanisms of PCB126.


Assuntos
Apoptose/efeitos dos fármacos , Dioxinas/toxicidade , Mitocôndrias/metabolismo , Bifenilos Policlorados/toxicidade , Receptores de Hidrocarboneto Arílico/metabolismo , Transdução de Sinais , Baço/efeitos dos fármacos , Baço/imunologia , Animais , Peso Corporal/efeitos dos fármacos , Citocinas/genética , Citocinas/metabolismo , Feminino , Masculino , Malondialdeído/metabolismo , Camundongos , Camundongos Endogâmicos ICR , RNA Mensageiro/genética , Espécies Reativas de Oxigênio/metabolismo , Receptores de Hidrocarboneto Arílico/genética , Baço/citologia , Baço/enzimologia , Superóxido Dismutase-1/metabolismo , Timo/efeitos dos fármacos , Timo/enzimologia , Timo/metabolismo
17.
Int J Biol Macromol ; 121: 930-935, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30342137

RESUMO

GP11 had been reported to have effectively anti-tumor activity by improving the immune function in our previous study. To avoid drawbacks of the 5-Fu, GP11 in combination with 5-Fu was investigated in this study. The results demonstrated that such synergism displayed enhance the anti-tumor activity of 5-Fu. Additionally, a strength effect was also observed in regulating immune function of GP11 and 5-Fu simultaneous administration, such as enhancing serum interleukin-2 (IL-2) and tumor necrosis factor-alpha (TNF-α) secretion, and increasing immune organs weights. Moreover, GP11 could improve the haematological and biochemical parameters deterioration, superoxide dismutase (SOD) activities reduction and malondialdehyde (MDA) levels enhancement in non-immune organs induced by 5-Fu. All these results illustrated that GP11 exhibited attenuated and synergized effect on 5-Fu by improving the immune function. It could be developed as an auxiliary preparation for chemotherapeutic drugs.


Assuntos
Antineoplásicos/farmacologia , Fluoruracila/farmacologia , Polissacarídeos Fúngicos/farmacologia , Grifola/química , Neoplasias/patologia , Animais , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Interações Medicamentosas , Feminino , Interleucina-2/sangue , Malondialdeído/metabolismo , Camundongos , Camundongos Endogâmicos ICR , Neoplasias/sangue , Neoplasias/metabolismo , Tamanho do Órgão/efeitos dos fármacos , Superóxidos/metabolismo , Fator de Necrose Tumoral alfa/sangue
18.
Neurosci Lett ; 432(2): 83-7, 2008 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-18243549

RESUMO

Production of reactive oxygen species (ROS) results in up-regulation of the extracellular signal-regulated kinase (ERK) cascade in response to numerous stimuli. Cerebral ischemia induces calcium-dependent kinase activation followed by ROS production. Here, we examined how ROS mediates the activation of ERK following cerebral ischemia in the rat hippocampus. We found that alpha-tocopherol, a free radical scavenger, attenuated the initial, robust activation of ERK by inhibiting Raf-1 dephosphorylation at Ser259. Alpha-tocopherol also down-regulated the second and mild activation of ERK through inhibition of Src-dependent phosphorylation of Raf-1 at Tyr340/341. Our results suggest that ROS production mediates the biphasic activation of ERK through different signaling cascades following post-ischemic reperfusion. Mediation of these signaling pathways involves changes in Raf-1 phosphorylation at different sites.


Assuntos
Isquemia Encefálica/enzimologia , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Estresse Oxidativo/fisiologia , Proteínas Proto-Oncogênicas c-raf/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/fisiologia , Animais , Encéfalo/enzimologia , Encéfalo/fisiopatologia , Isquemia Encefálica/fisiopatologia , Domínio Catalítico/efeitos dos fármacos , Domínio Catalítico/fisiologia , Ativação Enzimática/efeitos dos fármacos , Ativação Enzimática/fisiologia , Sequestradores de Radicais Livres/farmacologia , Masculino , Estresse Oxidativo/efeitos dos fármacos , Fosforilação/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Traumatismo por Reperfusão/enzimologia , Traumatismo por Reperfusão/fisiopatologia , Transdução de Sinais/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/fisiologia , alfa-Tocoferol/farmacologia , Quinases da Família src/metabolismo
19.
Biosens Bioelectron ; 91: 199-202, 2017 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-28011415

RESUMO

A simple and signal-amplified, label-free electrochemical impedimetric immunosensor for dibutyl phthalate (DBP), a type of phthalate ester, was developed using gold nanoparticles (AuNPs) induced signal amplification. The approach was based on an indirectly competitive binding system of coating antigen that coated on antigen/chitosan/MWCNTs@GONRs/GCE (modified electrodes), target (DBP) and anti-DBP antibody. Signal amplification was performed via the enlargement of AuNPs through NADH-promoted catalytic precipitation, which caused a marked increase in the electron-transfer resistance and electrostatic repulsion after an AuNP-labeled second antibody conjugated to anti-DBP. Under the optimized conditions, this method displayed: (i) low detection limits (7ng/mL, 10 times lower than the traditional ELISA method using the same antibody); (ii) satisfactory accuracy (recoveries, 86.0-120.4%) and agreement with corresponding ELISA method; (iii) high tolerance to some environmental interferents; and (iv) low cost and low sample consumption (6µL). Our results demonstrate the great potential and high efficiency of this immunosensor in practical applications for the cost-effective and sensitive monitoring of DBP in aquatic environments.


Assuntos
Dibutilftalato/análise , Técnicas Eletroquímicas/instrumentação , Ouro/química , Imunoensaio/instrumentação , Nanopartículas Metálicas/química , Rios/química , Poluentes Químicos da Água/análise , Anticorpos Imobilizados/química , Técnicas Biossensoriais/economia , Técnicas Biossensoriais/instrumentação , Quitosana/química , Técnicas Eletroquímicas/economia , Eletrodos , Monitoramento Ambiental/economia , Monitoramento Ambiental/instrumentação , Imunoensaio/economia , Limite de Detecção , Nanotubos de Carbono/química , Plastificantes/análise
20.
Zhong Yao Cai ; 29(10): 1098-100, 2006 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-17326415

RESUMO

OBJECTIVE: To study the adsorption and desorption behavior of macroporous adsorhption resin AB-8 for polysaccharides in exocarp of Ginkgo biloba L. and its effect factors. METHODS: The optimum purification conditions were investigated by singal factor experiments. RESULTS: The optimum conditions were as follows: the follow rate was 1.0 ml/min, solution concentration was 10 mg/ml and the pH was 7.4-7.6. CONCLUSION: AB-8 have an upper adsorption capacity for polysaccharides in exocarp of Ginkgo biloba L. and the elution is easy. The purification of its production is 81.3%.


Assuntos
Ginkgo biloba/química , Plantas Medicinais/química , Polissacarídeos/isolamento & purificação , Resinas Sintéticas , Adsorção , Frutas/química , Concentração de Íons de Hidrogênio , Casca de Planta/química , Polissacarídeos/análise , Espectrofotometria Ultravioleta , Tecnologia Farmacêutica/métodos
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