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31.
Severo Juliana Soares Morais Jennifer Beatriz Silva Beserra Jessica Batista dos Santos Loanne Rocha de Sousa Melo Stéfany Rodrigues de Sousa Gustavo Santos de Matos Neto Emídio Marques Henriques Gilberto Simeone do Nascimento Marreiro Dilina 《Biological trace element research》2020,193(1):81-88
Biological Trace Element Research - Excessive adipose tissue promotes the manifestation of endocrine disorders such as reduction of the secretion of zinc-α2-glycoprotein (ZAG), an adipokine... 相似文献
32.
Glaucio Monteiro Ferreira Juliana Gallottini de Magalhães Vinícius Gonçalves Maltarollo Thales Kronenberger Arasu Ganesan Flávio da Silva Emery 《Journal of biomolecular structure & dynamics》2020,38(2):354-363
AbstractSirtuin 2 is a key enzyme in gene expression regulation that is often associated with tumor proliferation control and therefore is a relevant anticancer drug target. Anilinobenzamide derivatives have been discussed as selective sirtuin 2 inhibitors and can be developed further. In the present study, hologram and three-dimensional quantitative structure–activity relationship (HQSAR and 3D-QSAR) analyses were employed for determining structural contributions of a compound series containing human sirtuin-2-selective inhibitors that were then correlated with structural data from the literature. The final QSAR models were robust and predictive according to statistical validation (q2 and r2pred values higher than 0.85 and 0.75, respectively) and could be employed further to generate fragment contribution and contour maps. 3D-QSAR models together with information about the chemical properties of sirtuin 2 inhibitors can be useful for designing novel bioactive ligands.Communicated by Ramaswamy H. Sarma 相似文献
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34.
Tarsila Barros Moraes Carlos Eduardo Diaz Jacques Andrea Pereira Rosa Giovana Reche Dalazen Melaine Terra Juliana Gonzalez Coelho Carlos Severo Dutra-Filho 《Cellular and molecular neurobiology》2013,33(2):253-260
Phenylketonuria (PKU) is an inherited metabolic disorder caused by deficiency of phenylalanine hydroxylase which leads to accumulation of phenylalanine and its metabolites in tissues of patients with severe neurological involvement. Recently, many studies in animal models or patients have reported the role of oxidative stress in PKU. In the present work we studied the effect of lipoic acid against oxidative stress in rat brain provoked by an animal model of hyperphenylalaninemia (HPA), induced by repetitive injections of phenylalanine and α-methylphenylalanine (a phenylalanine hydroxylase inhibitor) for 7 days, on some oxidative stress parameters. Lipoic acid prevented alterations on catalase (CAT) and superoxide dismutase (SOD), and the oxidative damage of lipids, proteins, and DNA observed in HPA rats. In addition, lipoic acid diminished reactive species generation compared to HPA group which was positively correlated to SOD/CAT ratio. We also observed that in vitro Phe inhibited CAT activity while phenyllactic and phenylacetic acids stimulated superoxide dismutase activity. These results demonstrate the efficacy of lipoic acid to prevent oxidative stress induced by HPA model in rats. The possible benefits of lipoic acid administration to PKU patients should be considered. 相似文献
35.
Camila Mello dos Santos Aline Blaya Martins Renato José de Marchi Juliana Balbinot Hilgert Fernando Neves Hugo Dalva Maria Pereira Padilha 《Gerodontology》2013,30(3):176-186
doi: 10.1111/j.1741‐2358.2012.00656.x Assessing changes in oral health‐related quality of life and its factors in community‐dwelling older Brazilians Objective: To describe changes in oral health‐related quality of life and to evaluate the associations of these changes in community‐dwelling older people. Materials and methods: In this longitudinal study a representative sample of 872 older people, living in Brazil, was evaluated during 2004. The follow‐up was carried out during 2008, with 587 older persons evaluated. A questionnaire assessing socio‐demographic information, health history, oral health‐impact profile and number of natural teeth was used. Changes in oral health‐related quality of life were categorized as improvement or deterioration. Data analysis was performed using a hierarchical approach based in a conceptual framework. A hierarchal approach was carried out using Poisson regressions. Results: Older persons living in rural areas, those who reported brushing once a day or less and older persons with fewer natural teeth had an increased chance of reporting deterioration in oral health‐related quality of life. Women and participants who received a minimum wage of less than US$219.50 were more likely to report improvement in oral health‐related quality of life. Conclusion: The results of this study suggest that changes in the oral health‐related quality of life are influenced by many of the variables that were included in the conceptual framework. 相似文献
36.
Juliana Trevisan da Rocha Simone Pinton Bibiana Mozzaquatro Gai Cristina Wayne Nogueira 《Biological trace element research》2013,154(3):372-378
Parkinson’s disease (PD) patients, in addition to motor dysfunction, also present alterations in pain sensation. The present study characterized the antinociceptive effects of diphenyl diselenide ((PhSe)2) in a model of nociception induced by unilateral, intrastriatal 6-hydroxydopamine (6-OHDA) injection in rats. Male adult Wistar rats received 20 μg/3 μl of 6-OHDA (in saline solution containing 0.02 % of ascorbic acid) or 3 μl of vehicle into the right striatum (1.0 mm anterior, 3.0 mm lateral, and 5.0 mm ventral—with respect to the bregma). Thirty days after injection, rats received (PhSe)2 intragastrically at a dose of 10 mg/kg 1 h before behavioral tests (von Frey hairs, hot plate, tail immersion, formalin, and open field). Our results demonstrated that 6-OHDA injection to rats augmented the response frequency of von Frey hairs (VHF) stimulation, besides reducing the thermal withdrawal latency in the hot plate test. Importantly, the (PhSe)2 treatment decreased the mechanical allodynia measured by the response frequency of VHF stimulation and diminished the thermal nociception in the hot plate test in 6-OHDA-injected rats. In conclusion, these results revealed that a single oral administration of (PhSe)2 1 h prior to the accomplishment of the behavioral tests was effective to attenuate the increased mechanical and thermal nociception caused by a single intrastriatal 6-OHDA injection to rats. Furthermore, other clarifying studies are warranted to improve the evidence bases for future clinical use of (PhSe)2 as a new alternative therapy for the treatment of painful symptoms associated to PD. 相似文献
37.
Julia Blümer Juliana Rey Leif Dehmelt Tomá? Mazel Yao-Wen Wu Philippe Bastiaens Roger S. Goody Aymelt Itzen 《The Journal of cell biology》2013,200(3):287-300
Eukaryotic cells critically depend on the correct regulation of intracellular vesicular trafficking to transport biological material. The Rab subfamily of small guanosine triphosphatases controls these processes by acting as a molecular on/off switch. To fulfill their function, active Rab proteins need to localize to intracellular membranes via posttranslationally attached geranylgeranyl lipids. Each member of the manifold Rab family localizes specifically to a distinct membrane, but it is unclear how this specific membrane recruitment is achieved. Here, we demonstrate that Rab-activating guanosine diphosphate/guanosine triphosphate exchange factors (GEFs) display the minimal targeting machinery for recruiting Rabs from the cytosol to the correct membrane using the Rab-GEF pairs Rab5A–Rabex-5, Rab1A-DrrA, and Rab8-Rabin8 as model systems. Specific mistargeting of Rabex-5/DrrA/Rabin8 to mitochondria led to catalytic recruitment of Rab5A/Rab1A/Rab8A in a time-dependent manner that required the catalytic activity of the GEF. Therefore, RabGEFs are major determinants for specific Rab membrane targeting. 相似文献
38.
Juliana L. França Marcelo R. Pinto Malson N. Lucena Daniela P. Garçon Wagner C. Valenti John C. McNamara Francisco A. Leone 《The Journal of membrane biology》2013,246(7):529-543
The stimulation by Mg2+, Na+, K+, NH4 +, and ATP of (Na+, K+)-ATPase activity in a gill microsomal fraction from the freshwater prawn Macrobrachium rosenbergii was examined. Immunofluorescence labeling revealed that the (Na+, K+)-ATPase α-subunit is distributed predominantly within the intralamellar septum, while Western blotting revealed a single α-subunit isoform of about 108 kDa M r. Under saturating Mg2+, Na+, and K+ concentrations, the enzyme hydrolyzed ATP, obeying cooperative kinetics with V M = 115.0 ± 2.3 U mg?1, K 0.5 = 0.10 ± 0.01 mmol L?1. Stimulation by Na+ (V M = 110.0 ± 3.3 U mg?1, K 0.5 = 1.30 ± 0.03 mmol L?1), Mg2+ (V M = 115.0 ± 4.6 U mg?1, K 0.5 = 0.96 ± 0.03 mmol L?1), NH4 + (V M = 141.0 ± 5.6 U mg?1, K 0.5 = 1.90 ± 0.04 mmol L?1), and K+ (V M = 120.0 ± 2.4 U mg?1, K M = 2.74 ± 0.08 mmol L?1) followed single saturation curves and, except for K+, exhibited site–site interaction kinetics. Ouabain inhibited ATPase activity by around 73 % with K I = 12.4 ± 1.3 mol L?1. Complementary inhibition studies suggest the presence of F0F1–, Na+-, or K+-ATPases, but not V(H+)- or Ca2+-ATPases, in the gill microsomal preparation. K+ and NH4 + synergistically stimulated enzyme activity (≈25 %), suggesting that these ions bind to different sites on the molecule. We propose a mechanism for the stimulation by both NH4 +, and K+ of the gill enzyme. 相似文献
39.
Raquel Fonseca-Maldonado Davi Serradella Vieira Juliana Sanchez Alponti Eric Bonneil Pierre Thibault Richard John Ward 《The Journal of biological chemistry》2013,288(35):25522-25534
Protein glycosylation is a common post-translational modification, the effect of which on protein conformational and stability is incompletely understood. Here we have investigated the effects of glycosylation on the thermostability of Bacillus subtilis xylanase A (XynA) expressed in Pichia pastoris. Intact mass analysis of the heterologous wild-type XynA revealed two, three, or four Hex8–16GlcNAc2 modifications involving asparagine residues at positions 20, 25, 141, and 181. Molecular dynamics (MD) simulations of the XynA modified with various combinations of branched Hex9GlcNAc2 at these positions indicated a significant contribution from protein-glycan interactions to the overall energy of the glycoproteins. The effect of glycan content and glycosylation position on protein stability was evaluated by combinatorial mutagenesis of all six potential N-glycosylation sites. The majority of glycosylated enzymes expressed in P. pastoris presented increased thermostability in comparison with their unglycosylated counterparts expressed in Escherichia coli. Steric effects of multiple glycosylation events were apparent, and glycosylation position rather than the number of glycosylation events determined increases in thermostability. The MD simulations also indicated that clustered glycan chains tended to favor less stabilizing glycan-glycan interactions, whereas more dispersed glycosylation patterns favored stabilizing protein-glycan interactions. 相似文献
40.
Gabriela Turk Yanina Ghiglione Juliana Falivene María Eugenia Socias Natalia Laufer Romina Soledad Coloccini Ana María Rodriguez María Julia Ruiz María ángeles Pando Luis David Giavedoni Pedro Cahn Omar Sued Horacio Salomon María Magdalena Gherardi 《Journal of virology》2013,87(13):7445-7462
The important role of the CD8+ T-cell response on HIV control is well established. Moreover, the acute phase of infection represents a proper scenario to delineate the antiviral cellular functions that best correlate with control. Here, multiple functional aspects (specificity, ex vivo viral inhibitory activity [VIA] and polyfunctionality) of the HIV-specific CD8+ T-cell subset arising early after infection, and their association with disease progression markers, were examined. Blood samples from 44 subjects recruited within 6 months from infection (primary HIV infection [PHI] group), 16 chronically infected subjects, 11 elite controllers (EC), and 10 healthy donors were obtained. Results indicated that, although Nef dominated the anti-HIV response during acute/early infection, a higher proportion of early anti-Gag T cells correlated with delayed progression. Polyfunctional HIV-specific CD8+ T cells were detected at early time points but did not associate with virus control. Conversely, higher CD4+ T-cell set points were observed in PHI subjects with higher HIV-specific CD8+ T-cell VIA at baseline. Importantly, VIA levels correlated with the magnitude of the anti-Gag cellular response. The advantage of Gag-specific cells may result from their enhanced ability to mediate lysis of infected cells (evidenced by a higher capacity to degranulate and to mediate VIA) and to simultaneously produce IFN-γ. Finally, Gag immunodominance was associated with elevated plasma levels of interleukin 2 (IL-2) and macrophage inflammatory protein 1β (MIP-1β). All together, this study underscores the importance of CD8+ T-cell specificity in the improved control of disease progression, which was related to the capacity of Gag-specific cells to mediate both lytic and nonlytic antiviral mechanisms at early time points postinfection. 相似文献