Showing papers by "Universidade Federal de Santa Catarina published in 2004"
TL;DR: In this article, the influence of l -ascorbic acid (AA) on mild steel corrosion in pH=2-6 solutions was investigated using electrochemical and weight loss techniques.
697 citations
TL;DR: This review focuses on the naturally-occurring compounds with anti-inflammatory properties and attempts to correlate their actions with the modulation of cytokines and associated intracellular signalling pathways.
Abstract: It has been widely shown that many plant-derived compounds present significant anti-inflammatory effects. For this reason, they represent potential molecules for the development of new drugs, especially designed for the treatment and/or control of chronic inflammatory states such as rheumatism, asthma, inflammatory bowel diseases, atherosclerosis, etc. This review focuses on the naturally-occurring compounds with anti-inflammatory properties and attempts to correlate their actions with the modulation of cytokines and associated intracellular signalling pathways; it continues the review published in the November, 2003 issue of Planta Medica. Abbreviations. AP-1:activator protein-1 CCR1:chemokine receptor 1 CINC-1:cytokine-induced neutrophil chemoattractant 1 COX:cyclooxygenase EGCG:(-)-epigallocatechin gallate ELAM-1:endothelial-leukocyte adhesion molecule-1 ERK:extracellular signal-regulated kinase GRO:growth-related oncogene HUVEC:human umbilical vein endothelial cells ICAM-1:intercellular adhesion molecule-1 IFN:interferon IL:interleukin iNOS:inducible nitric oxide synthase IRA:the natural interleukin receptor activation JAK:janus kinase JNK:c-Jun NH2-terminal kinase LPS:lipopolysaccharide MAPK:mitogen-activated protein kinases MCP:monocyte chemotactic protein MHC:major histocompatibility complex MIP:macrophage inflammatory protein MMP:matrix metalloproteinases MPO:myeloperoxidase NF-kappaBnuclear factor kappa B NO:nitric oxide PAF:platelet aggregation factor PGEE:prostaglandin PK:protein kinase PMA/TPA:phorbol myristate acetate RANTES:regulated upon activation normal T-cell expressed and secreted TGF-beta:transforming growth factor-beta TNFalpha:tumour necrosis factor VCAM-1:vascular cell adhesion molecule-1
413 citations
TL;DR: It is suggested that sepsis is a major public health problem in Brazilian ICUs, with an incidence density about 57 per 1000 patient-days, and there was a close association between ACCP/SCCM categories and mortality rate.
Abstract: Introduction
Consistent data about the incidence and outcome of sepsis in Latin American intensive care units (ICUs), including Brazil, are lacking. This study was designed to verify the actual incidence density and outcome of sepsis in Brazilian ICUs. We also assessed the association between the Consensus Conference criteria and outcome
391 citations
TL;DR: In this paper, the star formation history of Seyfert 2 nuclei is reconstructed by means of state-of-the-art population synthesis modelling of their spectra in the 3500−5200 A interval.
Abstract: We present a study of the stellar populations in the central ∼200 pc of a large and homogeneous sample comprising 79 nearby galaxies, most of which are Seyfert 2s. The star formation history of these nuclei is reconstructed by means of state-of-the-art population synthesis modelling of their spectra in the 3500‐5200 A interval. A quasar-like featureless continuum (FC) is added to the models to account for possible scattered light from a hidden active galactic nucleus (AGN). We find the following. (1) The star formation history of Seyfert 2 nuclei is remarkably heterogeneous: young starbursts, intermediate-age and old stellar populations all appear in significant and widely varying proportions. (2) A significant fraction of the nuclei show a strong FC component, but this FC is not always an indication of a hidden AGN: it can also betray the presence of a young, dusty starburst. (3) We detect weak broad Hβ emission in several Seyfert 2s after cleaning the observed spectrum by subtracting the synthesis model. These are most likely the weak scattered lines from the hidden broad-line region envisaged in the unified model, given that in most of these cases independent spectropolarimetry data find a hidden Seyfert 1. (4) The FC strengths obtained by the spectral decomposition are substantially larger for the Seyfert 2s which present evidence of broad lines, implying that the scattered nonstellar continuum is also detected. (5) There is no correlation between the star formation in the nucleus and either the central or overall morphology of the parent galaxies. Ke yw ords: galaxies: active ‐ galaxies: Seyfert ‐ galaxies: statistics ‐ galaxies: stellar content.
305 citations
TL;DR: More investigations on the molecular mechanisms and the antioxidant status in testis are necessary to ascertain the contribution of ROS to the tissue damage produced by spermatic cord torsion in experimental animals and humans.
302 citations
TL;DR: The epidemiological aspects of adults overweight and obesity as a considerable problem of public health are emphasized to mediate the consequences and connections of economic policies within the populations.
Abstract: Obesity, a disease of the Noncommunicable Disease Group, is the excess of body fat accumulated to an extent that health may be adversely affected. The etiology of obesity is a multifarious process that involves environmental and genetic factors. Nowadays, obesity is a world-wide public health problem showing an increased prevalence in developing countries, as well as in developed ones. The nutritional transition is a process of sequential changes in the nutrition and consumption patterns, that follows economic, social and demographic changes, and changes in the health profile of populations. In this new profile, the urbanization led to a change in behavior patterns of eating, and a decrease in the populations physical activity, both becoming important trends nowadays. The increase of obesity prevalence in Brazil is considerable and proportionally higher in low-income families. The nutritional epidemiological picture of Brazil shows a situation that chaims for public health strategies, able to solve the malnutrition and obesity trends in the same attention-model in health, and to mediate the consequences and connections of economic policies within the populations, process of disease and death. The aim of the present literature revision is to emphasize the epidemiological aspects of adults overweight and obesity as a considerable problem of public health.
293 citations
TL;DR: The main advances achieved in the last 5 years about the participation of kinin B1 receptors in painful and inflammatory disorders are remarked and some groups of chronic diseases are pointed out, in which the strategic development of nonpeptidic oral‐available and selective B1 receptor antagonists could have a potential relevant therapeutic interest.
Abstract: Kinins are a family of peptides implicated in several pathophysiological events. Most of their effects are likely mediated by the activation of two G-protein-coupled receptors: B1 and B2. Whereas B2 receptors are constitutive entities, B1 receptors behave as key inducible molecules that may be upregulated under some special circumstances. In this context, several recent reports have investigated the importance of B1 receptor activation in certain disease models. Furthermore, research on B1 receptors in the last years has been mainly focused in determining the mechanisms and pathways involved in the process of induction. This was essentially favoured by the advances obtained in molecular biology studies, as well as in the design of selective and stable peptide and nonpeptide kinin B1 receptor antagonists. Likewise, development of kinin B1 receptor knockout mice greatly helped to extend the evidence about the relevance of B1 receptors during pathological states. In the present review, we attempted to remark the main advances achieved in the last 5 years about the participation of kinin B1 receptors in painful and inflammatory disorders. We have also aimed to point out some groups of chronic diseases, such as diabetes, arthritis, cancer or neuropathic pain, in which the strategic development of nonpeptidic oral-available and selective B1 receptor antagonists could have a potential relevant therapeutic interest.
268 citations
TL;DR: In this paper, the cross product A × α G is shown to be associative, provided that A is semiprime and that G is a cross product of a partial action of a group on an associative algebra.
Abstract: Given a partial action a of a group G on an associative algebra A, we consider the crossed product A × α G. Using the algebras of multipliers, we generalize a result of Exel (1997) on the associativity of A × α G obtained in the context of C*-algebras. In particular, we prove that A × α G is associative, provided that A is semiprime. We also give a criterion for the existence of a global extension of a given partial action on an algebra, and use crossed products to study relations between partial actions of groups on algebras and partial representations. As an application we endow partial group algebras with a crossed product structure.
229 citations
TL;DR: Assessment of mutagenic potential of tributyltin (TBT) and inorganic lead (PbII) using samples of the fish Hoplias malabaricus using the comet assay and the piscine micronucleus and chromosome aberration tests indicated that TBT and PbII are potentially Mutagenic.
Abstract: Genotoxicity studies on toxic metals and their organic compounds are very important, especially so in the investigation of the effects of these compounds on the aquatic environments where they tend to accumulate. The use of endemic aquatic organisms as biological sentinels has proved useful to environmental monitoring. We assessed the mutagenic potential of tributyltin (TBT) and inorganic lead (PbII) using samples of the fish Hoplias malabaricus (commonly called traira) using the comet assay and the piscine micronucleus and chromosome aberration tests. Eighteen H. malabaricus were acclimatized in three individual aquariums, each containing six fish, six fish being exposed to 0.3 mg/g of body weight (bw) of TBT, six to 21 mg/g bw of PbII and six being used as controls. Exposure to TBT and PbII was achieved by feeding the fish every five days with Astyanax (a small fish that is part of the normal diet of H. malabaricus) which had been injected with solutions of TBT, PbII or with water (the control group). After two months the H. malabaricus were sacrificed and their peripheral blood collected and subjected to the comet and micronucleus assays, the chromosome aberration assay being conducted using kidney-tissue. Although the comet assay showed now mutagenic effects at the lead concentrations used but encountered results with TBT, the micronucleus and chromosome aberrations assays both indicated that TBT and PbII are potentially mutagenic (p < 0.01), the micronucleus assay showing morphological alterations of the nucleus.
209 citations
TL;DR: In this article, ω-(o-Alkylphenyl)alkanoic acids with 16, 18 and 20 carbon atoms were identified in archaeological pottery vessels from coastal sites in Southern Brazil.
185 citations
TL;DR: It is demonstrated that BK produces overt nociception mediated by TRPV1 receptor stimulation, via PLC pathway activation and LOX product formation, which is similar to that caused by capsaicin.
Abstract: 1. The vanilloid receptor (TRPV1) is viewed as a molecular integrator of several nociceptive stimuli. In the present study, we have investigated the role played by TRPV1 in the nociceptive response induced by the peripheral activation of kinin B(2) receptor in mice. 2. The intraplantar (i.pl.) administration of bradykinin (BK) and the selective B(2) agonist Tyr(8)-BK, or the vanilloid agonists resiniferatoxin and capsaicin, into the mouse paw induced a dose-related overt nociception of short duration. The B(2) receptor antagonist Hoe 140 inhibited BK-induced, but not capsaicin-induced, nociceptive response. On the other hand, the TRPV1 antagonist capsazepine inhibited both capsaicin- and BK-mediated nociception. 3. Repeated injections of BK or capsaicin produced desensitization to their nociceptive response. Capsaicin desensitization greatly reduced BK-induced nociception, but in contrast, the desensitization to BK increased the capsaicin response. 4. Administration of low doses of capsaicin or acidified saline did not produce nociception when administered alone, but caused a pronounced effect when administered in association with a subthreshold dose of BK. Moreover, the degeneration of the subset of primary afferent fibers, sensitive to capsaicin, abolished both capsaicin- and BK-induced nociception. 5. The inhibition of phospholipase C (PLC), protein kinase C or phospholipase A(2) markedly decreased the nociception caused by BK, but not that of capsaicin. BK administration increased leukotriene B(4) levels in the injected paw. Likewise, BK-induced overt nociception was decreased by lipoxygenase (LOX) inhibition. 6. These results demonstrate that BK produces overt nociception mediated by TRPV1 receptor stimulation, via PLC pathway activation and LOX product formation.
TL;DR: Results confirm and extend literature data, showing that caffeic acid derivatives exert in vitro and in vivo anti-inflammatory actions, being their actions mediated, at least in part by the scavenging of NO and their ability to modulate iNOS expression and probably that of other inflammatory mediators.
Abstract: Caffeic acid and some of its derivatives such as caffeic acid phenetyl ester (CAPE) and octyl caffeate are potent antioxidants which present important anti-inflammatory actions. The present study assessed the in vitro and in vivo effects of five caffeic acid derivatives (caffeic acid methyl, ethyl, butyl, octyl and benzyl esters) and compared their actions to those of CAPE. In the model of LPS-induced nitric oxide (NO) production in RAW 264.7 macrophages, the pre-incubation of all derivatives inhibited nitrite accumulation on the supernatant of stimulated cells, with mean IC50 (microM) values of 21.0, 12.0, 8.4, 2.4, 10.7 and 4.80 for methyl, ethyl, butyl, octyl, benzyl and CAPE, respectively. The effects of caffeic acid derivatives seem to be related to the scavenging of NO, as the compounds prevented SNAP-derived nitrite accumulation and decreased iNOS expression. In addition, butyl, octyl and CAPE derivatives significantly inhibited LPS-induced iNOS expression in RAW 264.7 macrophages. Extending the in vitro results, we showed that the pre-treatment of mice with butyl, octyl and CAPE derivatives inhibited carrageenan-induced paw edema and prevented the increase in IL-1beta levels in the mouse paw by 30, 24 and 36%, respectively. Butyl, octyl and CAPE derivatives also prevented carrageenan-induced neutrophil influx in the mouse paw by 28, 49 and 31%, respectively. Present results confirm and extend literature data, showing that caffeic acid derivatives exert in vitro and in vivo anti-inflammatory actions, being their actions mediated, at least in part by the scavenging of NO and their ability to modulate iNOS expression and probably that of other inflammatory mediators.
TL;DR: The study particularly focuses on work conditions of family health teams in Brazil, including strategies for revitalizing health care work and coping with alienating conditions in the work process.
Abstract: This literature review focused on the work process in health care, particularly issues linked to the Family Health Program. Since 1994, the Program has rapidly expanded health coverage for the Brazilian population, and as a result the Program's work force has also increased. The Program thus requires attention, allocation of responsibilities, and contributions of various types by stakeholders and institutions. The work occurs in the services sector, within a neoliberal scenario. Work in health care shares some characteristics with other occupations in the services sector, such as bureaucratization, the influence of capitalist division of labor, and difficulties in teamwork, in addition to little regard for the subjectivity of health system clients and workers. The study particularly focuses on work conditions of family health teams in Brazil, including strategies for revitalizing health care work and coping with alienating conditions in the work process. Finally, the study reiterates the dialectic condition of the work process in health care under the Family Health Program, with its possibilities for success, conceived and functioning in the midst of contradictions and difficulties.
TL;DR: In this paper, the authors present an efficient strategy for dealing with topology optimization associated with the problem of mass minimization under material failure constraints by combining an augmented Lagrangian technique for the stress constraints and a trust region box-type algorithm for the side constraints.
Abstract: This work presents an efficient strategy for dealing with topology optimization associated with the problem of mass minimization under material failure constraints. Although this problem characterizes one of the oldest mechanical requirements in structural design, only a few works dealing with this subject are found in the literature. Several reasons explain this situation, among them the numerical difficulties introduced by the usually large number of stress constraints. The original formulation of the topological problem (existence/non-existence of material) is partially relaxed by following the SIMP (Solid Isotropic Microstructure with Penalization) approach and using a continuous density field ź as the design variable. The finite element approximation is used to solve the equilibrium problem, as well as to control ź through nodal parameters. The formulation accepts any failure criterion written in terms of stress and/or strain invariants. The whole minimization problem is solved by combining an augmented Lagrangian technique for the stress constraints and a trust-region box-type algorithm for dealing with side constraints (0<źmin≤ź≤1) . Numerical results show the efficiency of the proposed approach in terms of computational costs as well as satisfaction of material failure constraints. It is also possible to see that the final designs define quite different shapes from the ones obtained in classical compliance problems.
TL;DR: It is demonstrated that jundia presents dietary protein sparing effect when the energy concentration increases from 3200 to 3650 kcal/kg, and also for body protein, ER, and ANPU.
TL;DR: Positive correlations were observed between the enzyme phospholipid hydroperoxide glutathione peroxidase (PHGPx) and malonaldehyde (MDA) levels after Fe and Cu exposure, indicating a protective role of PHGPx against lipid peroxidation, and suggesting the use of this enzyme as a new potential biomarker of toxicity associated with contaminant exposure in mussels.
TL;DR: The hypoglycaemic effect and the prompt efficiency of the kaempferitrin in stimulating [U-14C]-2-deoxi-D-glucose uptake in muscle constitute the first evidence to indicate that the acute effect of this compound on blood glucose lowering may occur as a consequence of the altered intrinsic activity of the glucose transporter not involving directly the synthesis of new carriers.
TL;DR: In this article, a quaternary chitosan salt (QCS) was synthesized with the aid of a substituent containing a Quaternary ammonium group, glycidyl trimethyl ammonium chloride.
Abstract: Quaternary chitosan salt (QCS) was synthesized with the aid of a substituent containing a quaternary ammonium group, glycidyl trimethyl ammonium chloride. The polymer was characterized by IR, 1H NMR, TGA and amount of quaternary ammonium groups. The studies on Cr(IV) ion adsorption equilibrium were conducted taking into account contact time, pH and amount of cross-linked QCS. The kinetic adsorption mechanism of the Cr(VI) ion was best described by the pseudo-second-order equation with a rate constant of 1.0 × 10−3 mg/g min. The Langmuir isotherm model was employed in order to adjust adsorption data, and the capacity was shown to depend on pH. The adsorption capacity for Cr(VI) at pH 9.0 was 30.2 mg/g (0.58 mmol/g), while at pH 4.5 the capacity was 68.3 mg/g (1.31 mmol/g). Cr(VI) ions can be eluted from cross-linked QCS by treatment with a 1 mol/l solution of NaCl/NaOH showing an efficiency of more than 95%.
TL;DR: Results strongly suggest that galantamine can prevent apoptotic cell death by inducing neuroprotection through a mechanism related to that described for nicotine, i.e. activation of nAChRs and upregulation of Bcl-2.
TL;DR: The variables observability and trialability were found to be the two most significant predictors of adoption and took place in 65% of the schools where pedagogical coordinators were brought under pressure by teachers to have the Internet adopted as a teaching tool.
Abstract: The present article describes a research that determined the factors influencing language schools in Brazil to adopt the Internet as a teaching tool. The theoretical framework used was Rogers, E. (1995). Diffusion of innovation (4th ed.). New York: The Free Press. theory of perceived attributes. A survey was carried out with 92 language schools located in Curitiba, South of Brazil. Results revealed that the Internet is adopted in 55% of the schools analysed. Both the model of linear multiple regression and the model of logistic regression predicted 77% of the cases of adoption and, therefore, represented satisfactorily the data from the questionnaire used. The variables observability and trialability were found to be the two most significant predictors of adoption. Adoption took place in 65% of the schools where pedagogical coordinators were brought under pressure by teachers to have the Internet adopted as a teaching tool, implying that this variable may influence the adoption rate. The variables size and amount of time the school has been functioning did not emerge as significant predictors.
TL;DR: The neural system intended to aid the control center operator in the task of fault section estimation can be applied to real bulk power systems and is able to deal with topological changes without having to retrain the neural networks.
Abstract: This paper presents a neural system intended to aid the control center operator in the task of fault section estimation. Its analysis is based on information about the operation of protection devices and circuit breakers. In order to allow the diagnosis task, the protection system philosophy of busbars, transmission lines, and transformers are modeled with the use of two types of neural networks: the general regression neural network and the multilayer perceptron neural network. The tool described in this paper can be applied to real bulk power systems and is able to deal with topological changes without having to retrain the neural networks.
TL;DR: A revisao de dados cientificos sobre o consumo de licopeno and sua acao como fator antioxidante can be found in this article.
Abstract: Este trabalho constitui uma revisao de dados cientificos sobre o consumo de licopeno e sua acao como fator antioxidante. O licopeno e considerado o carotenoide que possui a maior capacidade sequestrante do oxigenio singlete. Radicais livres agem continuamente no organismo, podendo desencadear danos celulares e serem os responsaveis pelo desenvolvimento de câncer e certas doencas cronicas. Estudos mostram que o licopeno protege moleculas de lipidios, lipoproteinas de baixa densidade, proteinas e DNA contra o ataque dos radicais, tendo um papel essencial na protecao de doencas. Como prevencao, preconiza-se o consumo de dietas ricas em alimentos fontes de licopeno: tomates e seus produtos (pure, pasta, catchup), mamao, pitanga e goiaba; que aportem cerca de 35mg de licopeno ao dia.
TL;DR: The results show that surface treatment is important for resin adhesion to ceramic and suggest that silane treatment was the main factor responsible for resin bonding to ceramic.
Abstract: PURPOSE The objective of this study was to evaluate the effect of different surface treatments on the microtensile bond strength (micro-tbs) of composite bonded to hot-pressed ceramic. The null hypothesis tested was that neither of the surface treatments (silanization or fluoric acid etching) would produce greater bond strength of composite resin to the ceramic. MATERIALS AND METHODS Four 7 x 7 x 5 mm hot-pressed ceramic blocks of IPS Empress 2 were fabricated and polished to 600 grit followed by sandblasting with 50 microm alumina. The ceramic blocks were then divided into four groups and submitted to the following surface treatments: Group 1: 9.5% hydrofluoric (HF) acid for 20 seconds and silane (S) for 3 minutes; Group 2: silane for 3 minutes; Group 3: 9.5% HF acid for 20 seconds; Group 4: no treatment. Scotchbond adhesive was applied to the treated ceramic surfaces and covered with Filtek Z250 composite resin. The composite-ceramic blocks were cut with an Isomet low speed diamond saw machine producing sticks (n = 25), which were loaded to failure under tension in an Instron Universal testing machine. The mean micro-tbs was analyzed with one-way ANOVA and Bonferroni "t" test. RESULTS All specimens of Group 4 experienced adhesive failure during the cutting of the block and were eliminated. The mean micro-tbs and standard deviations (SD) in megaPascals were: Group 1 = 56.8 (+/-10.4), Group 2 = 44.8 (+/-11.6), Group 3 = 35.1 (+/-7.7). Statistical analysis showed that the bond strength was significantly affected by surface treatment (p < 0.0001). Group 1 (HF + S) had the highest micro-tbs, and Group 2 (S) had higher micro-tbs than Group 3 (HF). The mode of fracture of the specimens was examined using scanning electron microscopy (SEM), and all fractures occurred within the adhesion zone. CONCLUSION The results show that surface treatment is important for resin adhesion to ceramic and suggestthat silane treatment was the main factor responsible for resin bonding to ceramic.
TL;DR: In this paper, the authors review the clinical, radiological, electrophysiological, pathological, and molecular aspects of Nasu-Hakola disease (polycystic lipomembranous osteodysplasia with sclerosing leukoencephalopathy or PLOSL).
Abstract: The authors review the clinical, radiological, electrophysiological, pathological, and molecular aspects of Nasu–Hakola disease (polycystic lipomembranous osteodysplasia with sclerosing leukoencephalopathy or PLOSL). Nasu-Hakola disease is a unique disease characterized by multiple bone cysts associated with a peculiar form of neurodegeneration that leads to dementia and precocious death usually during the fifth decade of life. The diagnosis can be established on the basis of clinical and radiological findings. Recently, molecular analysis of affected families revealed mutations in the DAP12 (TYROBP) or TREM2 genes, providing an interesting example how mutations in two different subunits of a multi-subunit receptor complex result in an identical human disease phenotype. The association of PLOSL with mutations in the DAP12 or TREM2 genes has led to improved diagnosis of affected individuals. Also, the possible roles of the DAP12/TREM2 signaling pathway in microglia and osteoclasts in humans are just beginning to be elucidated. Some aspects of this peculiar signaling pathway are discussed here.
TL;DR: It is demonstrated that agmatine antidepressant-like effects in the FST seem to be mediated, at least in part, by an interaction with 5- HT(1A/1B) and 5-HT(2) receptors.
TL;DR: This work presents an overview of the common methods for lipase immobilization in polymers and applications of these systems to obtain compounds of synthetic interest.
Abstract: The application of biocatalysis is a promising field related to new technologies for organic synthesis. The development of immobilization techniques is very important due to the multiple or repetitive use of a single batch of enzymes and the ability to stop the reaction rapidly, at any stage, by removing the enzymes. In most cases, after immobilization, enzymes and microorganisms maintain or even increase their activity and stability. This work presents an overview of the common methods for lipase immobilization in polymers and applications of these systems to obtain compounds of synthetic interest.
Journal Article•
TL;DR: The mammal fauna from Santa Catarina State, southern Brazil, is one of the least known of the country and works on terrestrial mammals are scarce and new species of aquatic mammals have been registered in the last years.
Abstract: List of mammals from Santa Catarina State, southern Brazil. The mammal fauna from Santa Catarina State, southern Brazil, is one of the least known of the country. Works on terrestrial mammals are scarce and new species of aquatic mammals have been registered in the last years. For that reason, a commented list of the mammals of Santa Catarina based on data gathered from scientific collections and bibliographical references are presented. One hundred and fifty-two species of confirmed occurrence, 59 species of possible occurrence and six species/subspecies with erroneous record for the state were registered.
TL;DR: This is the first report of an antidepressant-like effect of adenosine in mice, apparently mediated through an interaction with A1 and A2A receptors.
TL;DR: In this paper, the authors employed regression analysis to map out electrically and NMDA-induced single components of defensive behaviors produced by stepwise increasing stimulation of periaqueductal gray matter (PAG).
TL;DR: In this paper, el radical ABTS·+ formado tras the reaccion of 2,2'azinobis-(3-etilbenzotiazolin 6-acido sulfonico) (ABTS) with persulfato potasico, incubados a temperatura ambiente and durante 16 horas.
Abstract: Los antocianos son colorantes naturales pertenecientes al grupo de los flavonoides. Estan presentes en casi todas las plantas y en todas sus partes, sobretodo en flores y frutos (particularmente en bayas). Para determinar la actividad antioxidante de los pigmentos antocianicos se ha utilizado el radical ABTS·+ formado tras la reaccion de 2,2'azinobis-(3-etilbenzotiazolin 6-acido sulfonico) (ABTS) con persulfato potasico, incubados a temperatura ambiente y durante 16 horas. Se determino la capacidad antioxidante de cinco antocianos puros: delfinidina, cianidina, peonidina, pelargonidina y malvidina todos ellos glucosilados en el C-3 del anillo C con excepcion de la delfinidina. De los antocianos ensayados, delfinidina y cianidina 3-glucosido presentan mayor actividad antioxidante, 2 veces mas que el Trolox (antioxidante sintetico de referencia). Los demas antocianos tienen menor actividad pero potencial equiparable al Trolox. Por lo tanto, ademas de las caracteristicas colorantes, los antocianos poseen potente propiedad antioxidante.