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941.
Grace Y. Sun Zihong Chen Kimberly J. Jasmer Dennis Y. Chuang Zezong Gu Mark Hannink Agnes Simonyi 《PloS one》2015,10(10)
A large group of flavonoids found in fruits and vegetables have been suggested to elicit health benefits due mainly to their anti-oxidative and anti-inflammatory properties. Recent studies with immune cells have demonstrated inhibition of these inflammatory responses through down-regulation of the pro-inflammatory pathway involving NF-κB and up-regulation of the anti-oxidative pathway involving Nrf2. In the present study, the murine BV-2 microglial cells were used to compare anti-inflammatory activity of quercetin and cyanidin, two flavonoids differing by their alpha, beta keto carbonyl group. Quercetin was 10 folds more potent than cyanidin in inhibition of lipopolysaccharide (LPS)-induced NO production as well as stimulation of Nrf2-induced heme-oxygenase-1 (HO-1) protein expression. In addition, quercetin demonstrated enhanced ability to stimulate HO-1 protein expression when cells were treated with LPS. In an attempt to unveil mechanism(s) for quercetin to enhance Nrf2/HO-1 activity under endotoxic stress, results pointed to an increase in phospho-p38MAPK expression upon addition of quercetin to LPS. In addition, pharmacological inhibitors for phospho-p38MAPK and MEK1/2 for ERK1/2 further showed that these MAPKs target different sites of the Nrf2 pathway that regulates HO-1 expression. However, inhibition of LPS-induced NO by quercetin was not fully reversed by TinPPIX, a specific inhibitor for HO-1 activity. Taken together, results suggest an important role of quercetin to regulate inflammatory responses in microglial cells and its ability to upregulate HO-1 against endotoxic stress through involvement of MAPKs. 相似文献
942.
Natalia E. Bernardes Agnes A. S. Takeda Thiago R. Dreyer Fernanda Z. Freitas Maria Célia Bertolini Marcos R. M. Fontes 《PloS one》2015,10(6)
Neurospora crassa is a filamentous fungus that has been extensively studied as a model organism for eukaryotic biology, providing fundamental insights into cellular processes such as cell signaling, growth and differentiation. To advance in the study of this multicellular organism, an understanding of the specific mechanisms for protein transport into the cell nucleus is essential. Importin-α (Imp-α) is the receptor for cargo proteins that contain specific nuclear localization signals (NLSs) that play a key role in the classical nuclear import pathway. Structures of Imp-α from different organisms (yeast, rice, mouse, and human) have been determined, revealing that this receptor possesses a conserved structural scaffold. However, recent studies have demonstrated that the Impα mechanism of action may vary significantly for different organisms or for different isoforms from the same organism. Therefore, structural, functional, and biophysical characterization of different Impα proteins is necessary to understand the selectivity of nuclear transport. Here, we determined the first crystal structure of an Impα from a filamentous fungus which is also the highest resolution Impα structure already solved to date (1.75 Å). In addition, we performed calorimetric analysis to determine the affinity and thermodynamic parameters of the interaction between Imp-α and the classical SV40 NLS peptide. The comparison of these data with previous studies on Impα proteins led us to demonstrate that N. crassa Imp-α possess specific features that are distinct from mammalian Imp-α but exhibit important similarities to rice Imp-α, particularly at the minor NLS binding site. 相似文献
943.
Agnes Juhasz Yun Ge Susan Markel Alice Chiu Linda Matsumoto Josephus van Balgooy 《Free radical research》2013,47(6):523-532
The family of NADPH oxidase (NOX) genes produces reactive oxygen species (ROS) pivotal for both cell signalling and host defense. To investigate whether NOX and NOX accessory gene expression might be a factor common to specific human tumour types, this study measured the expression levels of NOX genes 1–5, dual oxidase 1 and 2, as well as those of NOX accessory genes NoxO1, NoxA1, p47phox, p67phox and p22phox in human cancer cell lines and in tumour and adjacent normal tissue pairs by quantitative, real-time RT-PCR. The results demonstrate tumour-specific patterns of NOX gene expression that will inform further studies of the role of NOX activity in tumour cell invasion, growth factor response and proliferative potential. 相似文献
944.
Patricia Vollú Silva Raquel Souza Cruz Luiz Sérgio Keim Geraldo Renato de Paula Bernadete Teixeira Ferreira Carvalho Leonardo Rocchetto Coelho Maria Cícera da Silva Carvalho Joel Mauricio Corrêa da Rosa Agnes Marie Sá Figueiredo Lenise Arneiro Teixeira 《Memórias do Instituto Oswaldo Cruz》2013,108(6):812-813
We analysed the antimicrobial susceptibility, biofilm formation and genotypic
profiles of 27 isolates of Staphylococcus haemolyticus obtained
from the blood of 19 patients admitted to a hospital in Rio de Janeiro, Brazil.
Our analysis revealed a clinical significance of 36.8% and a multi-resistance
rate of 92.6% among these isolates. All but one isolate carried the
mecA gene. The staphylococcal cassette chromosome
mec type I was the most prevalent mec
element detected (67%). Nevertheless, the isolates showed clonal diversity based
on pulsed-field gel electrophoresis analysis. The ability to form biofilms was
detected in 66% of the isolates studied. Surprisingly, no icaAD
genes were found among the biofilm-producing isolates. 相似文献
945.
Coupling of Mitochondrial Import and Export Translocases by Receptor-Mediated Supercomplex Formation
Jian Qiu Lena-Sophie Wenz Ralf M. Zerbes Silke Oeljeklaus Maria Bohnert David A. Stroud Christophe Wirth Lars Ellenrieder Nicolas Thornton Stephan Kutik Sebastian Wiese Agnes Schulze-Specking Nicole Zufall Agnieszka Chacinska Bernard Guiard Carola Hunte Bettina Warscheid Martin van der Laan Nikolaus Pfanner Nils Wiedemann Thomas Becker 《Cell》2013
946.
Agnes Mira Szabo Valeria Endresz Ferenc Somogyvari Andras Miczak Ildiko Faludi 《Molecular biology reports》2013,40(8):4721-4725
We studied the role of isocitrate lyase in the interaction between Mycobacterium bovis BCG and mice. ApoB100-only LDLR?/? (B6;129S-ApoBtm2SgyLdlrtm1Her/J) mice were inoculated with M. bovis BCG harbouring plasmids carrying the gene for isocitrate lyase. The presence of ~29 times more copies of this gene resulted in a higher bacterial yield in the spleens and lungs of the infected mice. The spleen was 3–4 times heavier, and in the spleen the bacteria survived over 10 days longer than did the bacteria with the control plasmid. Propionate was less toxic for bacteria carrying icl plasmids in vitro. This recombinant BCG can be a possible vaccine candidate. 相似文献
947.
Remo Sanges Yavor Hadzhiev Marion Gueroult-Bellone Agnes Roure Marco Ferg Nicola Meola Gabriele Amore Swaraj Basu Euan R. Brown Marco De Simone Francesca Petrera Danilo Licastro Uwe Str?hle Sandro Banfi Patrick Lemaire Ewan Birney Ferenc Müller Elia Stupka 《Nucleic acids research》2013,41(6):3600-3618
948.
Agnes B. Fogo Valentina Kon 《The international journal of biochemistry & cell biology》2010,42(9):1388-1397
The glomerular endothelial cells are unique both in location and anatomy compared to most other endothelial cells throughout the body. The absence of a diaphragm with retention of a basement membrane and fenestrations enable these uniquely situated cells to have a key role in filtration performed by the kidney. Interaction with other glomerular cells such as the podocytes and mesangial cells, as well as with circulating and infiltrating inflammatory cells, contribute to the final impact of the glomerular endothelial cells on maintenance of body fluid homeostasis and modulation of disease. Thus, endothelial cells contribute to hemodynamic function, reactive oxygen stress, regulate the balance between pro-thrombotic and anti-thrombotic forces, and importantly, contribute to fibrosis, the key injury of progressive chronic kidney disease. Repair of endothelial cell damage and restoration of segmentally sclerosed glomeruli are key areas considered for intervention in chronic kidney disease. This review will focus on the structure, function, and interplay of endothelial cells with other glomerular cells and systemic factors, their impact on renal disease and give rationale for possible intervention that may forestall progressive injuries. 相似文献
949.
Adrian V. Jaeggi Lynda P. Dunkel Maria A. Van Noordwijk Serge A. Wich Agnes A.L. Sura Carel P. Van Schaik 《American journal of primatology》2010,72(1):62-71
Studies of social learning in the wild are important to complement findings from experiments in captivity. In this field study, immature Bornean orangutans rarely foraged independently but consistently followed their mothers' choices. Their diets were essentially identical to their mothers' even though not all mothers had the same diet. This suggests vertical transmission of diet by enhancement. Also, immatures selectively observed their mothers during extractive foraging, which increased goal‐directed practice but not general manipulation of similar objects, suggesting observational forms of learning of complex skills. Teaching was not observed. These results are consistent with the reported presence of food traditions and skill cultures in wild orangutans. We suggest that food traditions can develop wherever association commonly allows for social learning. However, the capacity for observational learning, and thus more complex culture, is more likely to evolve among extractive foragers with prolonged association between adults and immatures. Am. J. Primatol. 72:62–71, 2010. © 2009 Wiley‐Liss, Inc. 相似文献