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31.
Devis Tuia Jordi Muñoz-Marí Mikhail Kanevski Gustavo Camps-Valls 《Journal of Signal Processing Systems》2011,65(3):301-310
Traditional kernel classifiers assume independence among the classification outputs. As a consequence, each misclassification receives the same weight in the loss function. Moreover, the kernel function only takes into account the similarity between input values and ignores possible relationships between the classes to be predicted. These assumptions are not consistent for most of real-life problems. In the particular case of remote sensing data, this is not a good assumption either. Segmentation of images acquired by airborne or satellite sensors is a very active field of research in which one tries to classify a pixel into a predefined set of classes of interest (e.g. water, grass, trees, etc.). In this situation, the classes share strong relationships, e.g. a tree is naturally (and spectrally) more similar to grass than to water. In this paper, we propose a first approach to remote sensing image classification using structured output learning. In our approach, the output space structure is encoded using a hierarchical tree, and these relations are added to the model in both the kernel and the loss function. The methodology gives rise to a set of new tools for structured classification, and generalizes the traditional non-structured classification methods. Comparison to standard SVM is done numerically, statistically and by visual inspection of the obtained classification maps. Good results are obtained in the challenging case of a multispectral image of very high spatial resolution acquired with QuickBird over a urban area. 相似文献
32.
33.
Gustavo D. Campagnaro Hamza A. A. Elati Sofia Balaska Maria Esther Martin Abril Manal J. Natto Fabian Hulpia Kelly Lee Lilach Sheiner Serge Van Calenbergh Harry P. de Koning 《International journal of molecular sciences》2022,23(2)
Toxoplasma gondii is unable to synthesize purines de novo, instead salvages them from its environment, inside the host cell, for which they need high affinity carriers. Here, we report the expression of a T. gondii Equilibrative Nucleoside Transporter, Tg244440, in a Trypanosoma brucei strain from which nucleobase transporters have been deleted. Tg244440 transported hypoxanthine and guanine with similar affinity (Km ~1 µM), while inosine and guanosine displayed Ki values of 4.05 and 3.30 µM, respectively. Low affinity was observed for adenosine, adenine, and pyrimidines, classifying Tg244440 as a high affinity oxopurine transporter. Purine analogues were used to probe the substrate-transporter binding interactions, culminating in quantitative models showing different binding modes for oxopurine bases, oxopurine nucleosides, and adenosine. Hypoxanthine and guanine interacted through protonated N1 and N9, and through unprotonated N3 and N7 of the purine ring, whereas inosine and guanosine mostly employed the ribose hydroxy groups for binding, in addition to N1H of the nucleobase. Conversely, the ribose moiety of adenosine barely made any contribution to binding. Tg244440 is the first gene identified to encode a high affinity oxopurine transporter in T. gondii and, to the best of our knowledge, the first purine transporter to employ different binding modes for nucleosides and nucleobases. 相似文献
34.
Júlio Santos-Terra Iohanna Deckmann Giovanna Carello-Collar Gustavo Della-Flora Nunes Guilherme Bauer-Negrini Gustavo Brum Schwingel Mellanie Fontes-Dutra Rudimar Riesgo Carmem Gottfried 《International journal of molecular sciences》2022,23(8)
Autism spectrum disorder (ASD) is a prevalent neurodevelopmental disorder characterized by several alterations, including disorganized brain cytoarchitecture and excitatory/inhibitory (E/I) imbalance. We aimed to analyze aspects associated with the inhibitory components in ASD, using bioinformatics to develop notions about embryonic life and tissue analysis for postnatal life. We analyzed microarray and RNAseq datasets of embryos from different ASD models, demonstrating that regions involved in neuronal development are affected. We evaluated the effect of prenatal treatment with resveratrol (RSV) on the neuronal organization and quantity of parvalbumin-positive (PV+), somatostatin-positive (SOM+), and calbindin-positive (CB+) GABAergic interneurons, besides the levels of synaptic proteins and GABA receptors in the medial prefrontal cortex (mPFC) and hippocampus (HC) of the ASD model induced by valproic acid (VPA). VPA increased the total number of neurons in the mPFC, while it reduced the number of SOM+ neurons, as well as the proportion of SOM+, PV+, and CB+ neurons (subregion-specific manner), with preventive effects of RSV. In summary, metabolic alterations or gene expression impairments could be induced by VPA, leading to extensive damage in the late developmental stages. By contrast, due to its antioxidant, neuroprotective, and opposite action on histone properties, RSV may avoid damages induced by VPA. 相似文献
35.
Renata Silvrio Robson Barth Andrea S. Heimann Patrícia Reckziegel Gustavo J. dos Santos Silvana Y. Romero-Zerbo Francisco J. Bermúdez-Silva Alex Rafacho Emer S. Ferro 《International journal of molecular sciences》2022,23(8)
Peptide DIIADDEPLT (Pep19) has been previously suggested to improve metabolic parameters, without adverse central nervous system effects, in a murine model of diet-induced obesity. Here, we aimed to further evaluate whether Pep19 oral administration has anti-obesogenic effects, in a well-established high-fat diet-induced obesity model. Male Swiss mice, fed either a standard diet (SD) or high-fat diet (HFD), were orally administrated for 30 consecutive days, once a day, with saline vehicle or Pep19 (1 mg/kg). Next, several metabolic, morphological, and behavioral parameters were evaluated. Oral administration of Pep19 attenuated HFD body-weight gain, reduced in approximately 40% the absolute mass of the endocrine pancreas, and improved the relationship between circulating insulin and peripheral insulin sensitivity. Pep19 treatment of HFD-fed mice attenuated liver inflammation, hepatic fat distribution and accumulation, and lowered plasma alanine aminotransferase activity. The inguinal fat depot from the SD group treated with Pep19 showed multilocular brown-fat-like cells and increased mRNA expression of uncoupling protein 1 (UCP1), suggesting browning on inguinal white adipose cells. Morphological analysis of brown adipose tissue (BAT) from HFD mice showed the presence of larger white-like unilocular cells, compared to BAT from SD, Pep19-treated SD or HFD mice. Pep19 treatment produced no alterations in mice behavior. Oral administration of Pep19 ameliorates some metabolic traits altered by diet-induced obesity in a Swiss mice model. 相似文献
36.
Mercedes Álvarez Isabel M. Moreno Silvia Pichardo Ana M. Cameán A. Gustavo González 《Food chemistry》2012
Fifty wines from the Denomination of origin (DO) of Condado de Huelva were analysed for mineral content by measuring 12 elements (Al, Ba, Ca, Cu, Fe, K, Mg, Mn, Na, P, Sr and Zn) using Inductively Coupled Plasma-Optical Emission Spectrometry (ICP-OES). Samples were previously digested by heating with H2O2/HNO3 mixture. The results obtained showed that metal data set were non-normally distributed and accordingly, non-parametric statistics were applied. The average levels (medians) of these elements found in the samples are as follows, in mg/L: 2.54 (Al); 0.06 (Ba); 82.58 (Ca); 0.21 (Cu); 3.53 (Fe); 865.34 (K); 68.87 (Mg); 0.71 (Mn); 32.77 (Na); 71.61 (P); 0.48 (Sr); 0.56 (Zn). The interrelation of metal couples was studied through the Spearman non-parametric sample correlation, being Fe/Al, P/Mg, and Zn/Ba the most important correlations established. As a result of this study, we can suggest that the contribution to the safety intake limits (per week) of the studied elements through the wine consumption is not significant. Actually, they range between 0.1% in Fe and 11.9% in Mg, for normal drinkers. 相似文献
37.
Gustavo Larsen Edgar Lotero Rubn D. Parra Lucía M. Petkovic Hugo S. Silva Srinivasanallur Raghavan 《Applied Catalysis A: General》1995,130(2):213-226
Palladium supported on sulfated zirconia (PdSZ) has been characterized by the n-butane isomerization reaction in the presence of hydrogen, X-ray absorption spectroscopy (XAS) and diffuse reflectance Fourier transform infrared spectroscopy (DRIFTS) of adsorbed carbon monoxide. Catalyst calcination at 873 K followed by hydrogen reduction at 513 K results in the formation of 30–40 Å Pd metal clusters, but the surface can only weakly adsorb CO, though stronger than Pd-free, sulfated zirconia catalysts. In the presence of hydrogen, PdSZ has a lower n-butane isomerization activity than SZ, and the Pd function cannot stabilize the reaction at low H2/n-butane ratios. 相似文献
38.
Keuri E. Rodrigues Aline Azevedo Pricila R. Gonalves Maria H. B. Pontes Gustavo M. Alves Ruan R. Oliveira Cristine B. Amarante Joo P. M. Issa Raquel F. Gerlach Alejandro F. Prado 《International journal of molecular sciences》2022,23(5)
Atherogenic events promote changes in vessel walls, with alteration of the redox state, and increased activity of matrix metalloproteinases (MMPs). Thus, this study aims to evaluate aortic remodeling, MMP activity, and reactive oxygen species (ROS) levels after treatment with doxycycline in ApoE-⁄- and ovariectomized mice (OVX). Female ApoE-⁄--knockout mice (5 weeks) were submitted to ovariectomy surgery to induce experimental menopause. They then received chow enriched with 1% cholesterol to induce hypercholesterolemia. The animals were divided into two experimental groups: ApoE-⁄-/OVX vehicle and ApoE-⁄-/OVX doxycycline (30 mg/kg) administered by gavage once a day for 28 days (15th to the 18th week of life). Blood samples were collected to measure total cholesterol and fractions. The aorta was used for morphometry and to measure the activity and expression of MMP-2 and ROS levels. The ApoE-⁄-/OVX doxycycline group showed no change in total and fraction cholesterol levels. However, there was a reduction in ROS levels, MMP-2 expression, and activity that correlated with a decrease in atherosclerotic lesions relative to the ApoE-⁄-/OVX vehicle (p > 0.05). Therefore, we conclude that doxycycline in ApoE-⁄-/OVX animals promotes a reduction in atherosclerotic lesions by reducing ROS and MMP-2 activity and expression. 相似文献
39.
Marzuq A. Ungogo Gustavo D. Campagnaro Ali H. Alghamdi Manal J. Natto Harry P. de Koning 《International journal of molecular sciences》2022,23(5)
The animal trypanosomiases are infections in a wide range of (domesticated) animals with any species of African trypanosome, such as Trypanosoma brucei, T. evansi, T. congolense, T. equiperdum and T. vivax. Symptoms differ between host and infective species and stage of infection and are treated with a small set of decades-old trypanocides. A complication is that not all trypanosome species are equally sensitive to all drugs and the reasons are at best partially understood. Here, we investigate whether drug transporters, mostly identified in T. b. brucei, determine the different drug sensitivities. We report that homologues of the aminopurine transporter TbAT1 and the aquaporin TbAQP2 are absent in T. congolense, while their introduction greatly sensitises this species to diamidine (pentamidine, diminazene) and melaminophenyl (melarsomine) drugs. Accumulation of these drugs in the transgenic lines was much more rapid. T. congolense is also inherently less sensitive to suramin than T. brucei, despite accumulating it faster. Expression of a proposed suramin transporter, located in T. brucei lysosomes, in T. congolense, did not alter its suramin sensitivity. We conclude that for several of the most important classes of trypanocides the presence of specific transporters, rather than drug targets, is the determining factor of drug efficacy. 相似文献
40.
Siluana Katia Tischer Seraglio Luciano Valdemiro Gonzaga Mayara Schulz Luciano Vitali Gustavo Amadeu Micke Ana Carolina Oliveira Costa Roseane Fett Graciele Da Silva Campelo Borges 《International Journal of Food Science & Technology》2018,53(8):1824-1831
This study evaluated the effects of different gastrointestinal digestion models in vitro on the bioaccessibility of phenolics and antioxidant activity in juçara frozen pulp. In the sequence, method 3 was applied to juçara fruit in three different stages of maturation (vitrin – reddish fruits, mature – purple fruits, tuíra – deep purple fruits). In the method applied, the final pH adopted was 5.0, in order to avoid interference in the assay used to determine the antioxidant activity, and BHT was used to prevent excessive oxidation in the system. In this method, higher values for antioxidant activity were obtained (3574.95–3719.10 μmol L?1 Trolox 100 g?1 pulp) compared with the other two methods tested (1969.14–3034.74 μmol L?1 Trolox 100 g?1 pulp). In relation to juçara fruit, the mature stage was found to be ideal for processing, showing generally higher values of the bioaccessibility for phenolics and antioxidant activity compared to other maturation stages. 相似文献