Showing papers by "Universidade Federal de Santa Maria published in 2011"
580 citations
TL;DR: The potential therapeutic use of simple organoselenium compounds has not yet been sufficiently explored and this class of compounds cannot discard as promising pharmaceutical agents, in effect, the future of the organochalcogens as pharmacological agents will depend on more detailed toxicological studies in the oncoming years.
Abstract: The advance in the area of synthesis and reactivity of organoselenium, as well as the discovery that selenium was the cause of severe intoxication episodes of livestock in the 1930s and the subsequent determination that selenium was an essential trace element in the diet for mammals, has motivated intense studies of the biological properties of both organic and inorganic selenium compounds. In this review, we shall cover a wide range of toxicological and pharmacological effects, in which organoselenium compounds are involved but the effects of inorganic compounds were not discussed in detail here. The molecular toxicity of inorganic selenium was described in relation to its interaction with endogenous –SH groups to allow a comparison with that of synthetic organoselenium compounds. Furthermore, in view of the recent points of epidemiological evidence that overexposure to selenium can facilitate the appearance of chronic degenerative diseases, we also briefly revised the history of selenium toxicity and physiology and how environmental selenium can reach inside the mammalian cells. The biological narrative of the element selenium, in the last century, has been marked by a contrast between its toxic and its beneficial effects. Thus, the potential therapeutic use of simple organoselenium compounds has not yet been sufficiently explored and, consequently, we cannot discard this class of compounds as promising pharmaceutical agents. In effect, the future of the organochalcogens as pharmacological agents will depend on more detailed toxicological studies in the oncoming years.
421 citations
TL;DR: Experimental studies provide the biochemical bases to the understanding of MeHg neurotoxicity, contributing to the discovery of endogenous and exogenous molecules that counteract such toxicity and provide efficacious means for ablating this vicious cycle.
374 citations
TL;DR: A review of MeHg-induced neurotoxicity is presented in this paper, where the authors summarize and discuss data from experimental and epidemiological studies that have been important in clarifying the molecular events which mediate MEHginduced oxidative damage and, consequently toxicity.
283 citations
TL;DR: Serum NO(x) measured by the modified Griess method can be applied easily to the Cobas Mira clinical chemistry analyzer, and was linear, precise, and accurate.
252 citations
TL;DR: In this article, the real durability of olefin polymers may be much shorter than centuries, as in less than one year the mechanical properties of all samples decreased virtually to zero, as a consequence of severe oxidative degradation, that resulted in substantial reduction in molar mass accompanied by a significant increase in content of carbonyl groups.
200 citations
TL;DR: In this paper, the authors applied ultrasound to diesel oil and petroleum product feedstock containing model sulfur compounds (benzothiophene, dibenzothiophen, and dimethyldibenzethiophene).
159 citations
TL;DR: A method for the simultaneous determination of pesticides, biopesticides and mycotoxins from organic products was developed and successfully applied to the analysis of organic food products, detecting analytes belonging to the three types of compounds.
158 citations
TL;DR: In this article, a multiresidue method for the determination of 24 pesticides in wheat, white flour and bran using gas chromatography coupled to mass spectrometry with negative chemical ionisation and selected ion monitoring was developed and validated.
150 citations
TL;DR: In this paper, the residual RHA was used as nature without any previous grinding, and the fresh and mechanical properties and the water permeability were analyzed in concretes replacing concrete by residual Rha.
144 citations
TL;DR: In this article, the authors studied the phenolic compounds identified in rice, their antioxidant activity and their potential beneficial effects on health, such as reduction of oxidative stress, aid in the prevention of cancer, cardiovascular diseases and complications of diabetes, among others.
Abstract: The aim of this work was to study the phenolic compounds identified in rice, their antioxidant activity and their potential beneficial effects on health. In vitro and in vivo studies evaluating the rice grains with different pericarp colour (light brown, red and black) showed potential beneficial effects on health related to the polyphenol content of the grain, such as reduction of oxidative stress, aid in the prevention of cancer, cardiovascular diseases and complications of diabetes, among others. Key words : rice, red rice, black rice, polyphenols, antioxidant, biological effect * Author for correspondence: melmelissaw@hotmail.com INTRODUCTION Several studies have demonstrated the importance of diet in the control of chronic diseases, such as cancer and cardiovascular problems (Birt et al., 2001; Kris-Etherton et al., 2002; Stanner et al., 2003; Houston, 2005). The consumption of fruits, legumes, vegetables and whole grains results a reduced risk of developing these diseases. This could be attributed to the presence of natural antioxidants in these foods, such as ascorbic acid, tocopherols, carotenoids and phenolic compounds (polyphenols) (Melendez-Martinez et al., 2004; Choi et al., 2007), besides other bioactive compounds. Among the compounds with antioxidant activity, polyphenols are important. These are found in a great variety of foods, such as apples, mulberries, cherries, grapes, raspberries, citric fruits, onions, spinach, peppers, oat, wheat, black tea, wine and chocolate, among others (Holden et al., 2005; Dimitrios, 2006). These compounds have demonstrated higher in vitro antioxidant capacity than other antioxidants, such as ascorbic acid and α-tocopherol (Pulido et al., 2000), emphasising the importance of polyphenols as antioxidants in the diet. Although polyphenols are found in several foods, variation is observed in the concentration and type of these compounds due to genetic and environmental factors and processing conditions (Kris-Etherton et al., 2002). Hence, the concentration of phenolic compounds varies greatly among the diets, depending on the type and quantity of food consumed. Rice, being one of the most produced and consumed cereals in the world, has an important role in the relation between the diet and health. Several compounds with antioxidant activity have been identified in rice, including phenolic compounds, tocopherols, tocotrienols and γ-oryzanol (Iqbal et al., 2005). The phenolic
TL;DR: Results show for the first time that nitrite has antihypertensive effects in 2K1C hypertensive rats, which may be due to its antioxidant properties resulting from vascular NADPH oxidase activity inhibition.
TL;DR: There was a decrease in the skin permeability coefficient of the drug by nanoencapsulation, independently of the dosage form, meaning that the drug is retained for a longer time on the skin surface.
TL;DR: CCFO exhibited a similar profile of topical anti-inflammatory activity to that of drugs that classically modulate the production of arachidonic acid metabolites, which indicates the potential application of CCFO as an important herbal medicine to be used against skin inflammatory diseases.
TL;DR: The results suggest that the presence of the essential oil of L. alba improves the redox state in the evaluated tissues, both under hyperoxia and under hypoxia.
TL;DR: Mexican oregano oil and its main component, carvacrol, are able to inhibit different human and animal viruses in vitro and justify more detailed studies.
TL;DR: The susceptibility to biodeterioration of biodiesel, diesel, and diesel containing 5, 10, and 20% biodiesel was evaluated using fungi isolated from contaminated oil systems, andYeasts had the highest rates of degradation, especially Candida silvicola, with 100% degradation of all esters.
TL;DR: Results showed that microglia are more sensitive to MeHg than astrocytes, a finding that is consistent with their higher Hg uptake and lower basal GSH levels, as well as mercury (Hg) uptake and the expression of NF‐E2‐related factor 2 (Nrf2).
Abstract: As the two major glial cell types in the brain, astrocytes and microglia play pivotal but different roles in maintaining optimal brain function. Although both cell types have been implicated as major targets of methylmercury (MeHg), their sensitivities and adaptive responses to this metal can vary given their distinctive properties and physiological functions. This study was carried out to compare the responses of astrocytes and microglia following MeHg treatment, specifically addressing the effects of MeHg on cell viability, reactive oxygen species (ROS) generation and glutathione (GSH) levels, as well as mercury (Hg) uptake and the expression of NF-E2-related factor 2 (Nrf2). Results showed that microglia are more sensitive to MeHg than astrocytes, a finding that is consistent with their higher Hg uptake and lower basal GSH levels. Microglia also demonstrated higher ROS generation compared with astrocytes. Nrf2 and its downstream genes were upregulated in both cell types, but with different kinetics (much faster in microglia). In summary, microglia and astrocytes each exhibit a distinct sensitivity to MeHg, resulting in their differential temporal adaptive responses. These unique sensitivities appear to be dependent on the cellular thiol status of the particular cell type.
TL;DR: The results demonstrated an increase in substances reactive to thiobarbituric acid (TBARS) and carbonyl protein levels in the AMI and risk groups and a decrease in nonenzymatic antioxidants such as vitamin C and vitamin E was observed in AMI patients when compared with the healthy group and the risk group.
Abstract: Acute myocardial infarction (AMI) is a highly dynamic event, which is associated with increasing production of reactive oxygen species (ROS). The imbalance between ROS production and antioxidant defenses leads to the condition known as oxidative stress. The most widely recognized effect of increasing oxidative stress is the oxidation and damage of macromolecules, membranes, proteins, and DNA. Therefore, in this study we sought to evaluate oxidative stress and antioxidant defenses in patients with AMI. Lipid peroxidation, protein carbonyl levels, and enzymatic and nonenzymatic antioxidants were assessed in samples obtained from 40 AMI patients and 40 control patients. AMI was characterized by clinical, electrocardiographic, and laboratory criteria. The control group was divided into two groups of 20 patients: a control group with healthy patients and a risk group. Our results demonstrated an increase in substances reactive to thiobarbituric acid (TBARS) and carbonyl protein levels in the AMI and risk groups. In addition, a positive correlation was found between TBARS, carbonyl protein levels, and troponin I in AMI patients. Surprisingly, for the enzymatic antioxidant defenses, catalase and superoxide dismutase, we observed an increase in these parameters in the AMI and risk groups when compared with healthy patients. However, a decrease in nonenzymatic antioxidants such as vitamin C and vitamin E was observed in AMI patients when compared with the healthy group and the risk group. The increase in oxidative stress was probably a result of the elevation in ROS production due to the ischemic/reperfusion event that occurs in AMI, in addition to the decrease of nonenzymatic antioxidant defenses.
TL;DR: This review aims to describe the analytical methodologies utilized for the determination of adulterants in slimming phytotherapeutic formulations and some important adulteration cases, which occurred mainly in Europe, Asia, Brazil, and the USA.
TL;DR: In this article, the stellar and gaseous kinematics, as well as the emission-line flux distributions and ratios, from the inner ≈450-pc radius of the Seyfert 2 galaxy Mrk-1157, using two-dimensional near-infrared J- and Kl-band spectra obtained with the Gemini Near-Infrared Integral-Field Spectrograph instrument at a spatial resolution of ≈35pc.
Abstract: We have mapped the stellar and gaseous kinematics, as well as the emission-line flux distributions and ratios, from the inner ≈450 pc radius of the Seyfert 2 galaxy Mrk 1157, using two-dimensional near-infrared J- and Kl-band spectra obtained with the Gemini Near-Infrared Integral-Field Spectrograph instrument at a spatial resolution of ≈35 pc and velocity resolution of ≈40 km s−1.
The stellar velocity field shows a rotation pattern, with a discrete S-shaped zero velocity curve – a signature of a nuclear bar. The presence of a bar is also supported by the residual map between the observed rotation field and a model of circular orbits in a Plummer potential. The stellar velocity dispersion (σ*) map presents a partial ring of low-σ* values (50–60 km s−1) at 250 pc from the nucleus surrounded by higher σ* values from the galaxy bulge. We propose that this ring has origin in kinematically colder regions with recent star formation. The stellar velocity dispersion of the bulge (100 km s−1) implies in a black hole mass of MBH= 8.3+3.2− 2.2× 106 M⊙.
Emission-line flux distributions are most extended along the position angle PA = 27°/153°, reaching at least 450 pc from the nucleus and following the orientation observed in previous optical emission-line [O iii] imaging and radio jets. The molecular hydrogen gas has an excitation temperature Texc≈ 2300 K and its emission is dominated by thermal processes, mainly due to X-ray heating by the active nucleus, with a possible small contribution from shocks produced by the radio jet. The [Fe ii] excitation has a larger contribution from shocks produced by the radio jet, as evidenced by the line-ratio maps and velocity dispersion maps, which show spatial correlation with the radio structures. The coronal lines are resolved, extending up to ≈150 pc and are also slightly more extended along PA = 27°/153°.
The gaseous kinematics show two components: one due to the gas located in the galaxy plane, in similar rotation to that of the stars, and another in outflow, which is oriented close to the plane of the sky, thus extending to high latitudes, as the galaxy plane is inclined by ≈45° relative to the plane of the sky. The gas rotating in the plane dominates the H2 and Paβ emission, while the gas in outflow is observed predominantly in [Fe ii] emission. The [Fe ii] emission is originated in gas being pushed by the radio jet, which destroys dust grains, releasing Fe. From the outflow velocities and implied geometry, we estimate a mass-outflow rate of for the ionized gas and a kinetic power for the outflow of .
The distinct flux distributions and kinematics of the H2- and [Fe ii]-emitting gas, with the former more restricted to the plane of the galaxy and the latter tracing the outflows related to radio jets, are a common characteristic of six Seyfert galaxies (ESO 428-G14, NGC 4051, 7582 and 4151, Mrk 1066, and now Mrk 1157) we have studied so far using similar two-dimensional observations and other two (Circinus and NGC 2110) using long-slit observations. We conclude that the H2 emission surrounding the nucleus in the galaxy plane is a tracer of the gas feeding to the active nucleus, while the [Fe ii] emission is a tracer of its feedback.
TL;DR: Anxious mothers presented higher scores in the parent distress domain, and Mean ECOHIS total score was not influenced by maternal dental anxiety, however, anxiety had a negative effect on the perception of the impact of the child’s oral health problems in the family, affecting theparent distress domain.
Abstract: The aim of this study was to determine the influence of maternal dental anxiety on perceptions about oral health–related quality of life (OHRQoL) of preschool children. A cross-sectional study was conducted with 608 mother–child dyads during the Children’s National Immunization Campaign in Pelotas, Brazil. Mothers answered a questionnaire on dental anxiety (DAS), socioeconomic status, use of dental services, and perception of their child’s OHRQoL (ECOHIS). The ECOHIS includes a child impact section (symptoms, function, psychological, self-image/social interaction domains) and a family impact section (parent distress and family function domains). Clinical examination of the children was performed to assess dental caries, dental trauma, and occlusal traits occurrence. The association assessment used Poisson regression models (RR; 95%CI, P ≤ 0.05). Anxious mothers presented higher scores in the parent distress domain. Higher impacts on OHRQoL were observed in children presenting untreated dental caries; children whose mothers had not completed primary education; and those who had non-regular use of dental services. Mean ECOHIS total score was not influenced by maternal dental anxiety. However, anxiety had a negative effect on the perception of the impact of the child’s oral health problems in the family, affecting the parent distress domain.
TL;DR: In this paper, a cotidiano de las personas of la comunidad asistida por una Unidad de Salud de la Familia, en el municipio de Rio Grande do Sul, sobre the uso terapeutico de las plantas medicinales in la atencion de la salud.
Abstract: El objetivo del trabajo fue conocer el cotidiano de las personas de la comunidad asistida por una Unidad de Salud de la Familia, en el municipio de Rio Grande do Sul, sobre el uso terapeutico de las plantas medicinales en la atencion de la salud. La investigacion cualitativa, fue realizada con colecta de datos por medio de entrevista semi-estructurada y observacion participante. Los diez entrevistados, usuarios de plantas medicinales, adscritos a la referida unidad, fueran seleccionados por medio de la red de relaciones. El analisis tematico permitio el surgimiento de las categorias. Se constato que el uso de te casero es comun entre los participantes y que la mayoria de las plantas medicinales utilizadas por los entrevistados tienen sus indicaciones terapeuticas populares similares a las encontradas en la literatura cientifica. Se cree que la investigacion tiene importancia para los enfermeros y para la sociedad, pues apunta para la necesidad de una aproximacion entre el saber popular y el conocimiento cientifico, y tambien para la creacion de proyectos que trabajan con este tema.
TL;DR: In this article, the authors investigate the possible interaction of the flavonoid eriodictyol with the TRPV1 receptor and determine its putative antinociceptive and hyperthermic effects.
TL;DR: Inequalities in the distribution of dental caries were observed and socioeconomic factors were found to be strong predictors of the prevalence of oral disease in children of this age group.
Abstract: We assessed the inequality in the distribution of dental caries and the association between indicators of socioeconomic status and caries experience in a representative sample of schoolchildren. This study followed a cross-sectional design, with a sample of 792 schoolchildren aged 12 years, representative of this age group in Santa Maria, RS, Brazil. Guardians answered questions on socioeconomic status and a dental examination provided information on the dental caries experience (DMF-T). Inequality in dental caries distribution was measured by the Gini coefficient and the Significant Caries Index (SiC). The assessment of association used Poisson regression models. Socioeconomic factors were associated with prevalence of dental caries for the whole sample and also for individuals with a high-caries level. Children from low-income households had the highest prevalence of dental caries. The Gini coefficient was 0.7 and the SiC Index 2.5. The percentage of caries prevalence was 39.3% (95% CI: 35.8%-42.8%) and the mean for DMF-T was 0.9 (± SD 1.5). Inequalities in the distribution of dental caries were observed and socioeconomic factors were found to be strong predictors of the prevalence of oral disease in children of this age group.
TL;DR: In this paper, the authors presented stellar and gaseous kinematics of the inner ≈350-pc radius of the Seyfert galaxy Mrk 1066 derived from J and K 1 bands data obtained with the Gemini's Near-Infrared Integral Field Spectrograph (NIFS) at a spatial resolution of ≈35 pc.
Abstract: We present stellar and gaseous kinematics of the inner ≈350-pc radius of the Seyfert galaxy Mrk 1066 derived from J and K 1 bands data obtained with the Gemini's Near-Infrared Integral Field Spectrograph (NIFS) at a spatial resolution of ≈35 pc. The stellar velocity field is dominated by rotation in the galaxy plane but shows an S-shape distortion along the galaxy minor axis which seems to be due to an oval structure seen in an optical continuum image. Along this oval, between 170 and 280 pc from the nucleus we find a partial ring of low σ * (≈50 km s -1 ) attributed to an intermediate-age stellar population. The velocity dispersion of the stellar bulge (σ * ≈ 90 km s -1 ) implies a supermassive black hole mass of ≈5.4 x 10 6 M ⊙ . From measurements of the emission-line fluxes and profiles ([P II]λ1.1886 μm, [Fe II]λ1.2570 μm, Paβ and H 2 λ2.1218 μm), we have constructed maps for the gas centroid velocity, velocity dispersion as well as channel maps. The velocity fields for all emission lines are dominated by a similar rotation pattern to that observed for the stars, but are distorted by the presence of two structures: (i) a compact rotating disc with radius r ≈ 70 pc; (ii) outflows along the radio jet which is oriented approximately along the galaxy major axis. The compact rotating disc is more conspicuous in the H 2 emitting gas, which presents the smallest σ values (≤70 km s -1 ) and most clear rotation pattern, supporting a location in the galaxy plane. We estimate a gas mass for the disc of ~10 7 M ⊙ . The H 2 kinematics further suggests that the nuclear disc is being fed by gas coming from the outer regions. The outflow is more conspicuous in the [Fe II] emitting gas, which presents the highest σ values (up to 150 km s -1 ) and the highest blue and redshifts of up to 500 km s -1 , while the highest stellar rotation velocity is only ≈ 130 km s -1 . We estimate a mass-outflow rate in ionized gas of ≈ 6 x 10 -2 M ⊙ yr -1 . The derived kinematics for the emitting gas is similar to that observed in previous studies supporting that the H 2 is a tracer of the active galactic nucleus feeding and the [Fe II] of its feedback.
TL;DR: The organ system most frequently affected by neoplastic disease was the alimentary tract and was attributed to a high incidence of squamous cell carcinoma of the upperAlimentary tract associated with the chronic ingestion of bracken fern.
TL;DR: The Nibelungen hydrothermal field is located at 8 degrees 18'S, about 9 km off-axis of the Mid-Atlantic Ridge (MAR), at 3000 m water depth, 372 degrees C hot, acidic fluids emanate directly from the bottom, without visible sulfide chimney formation as mentioned in this paper.
TL;DR: In this article, the feasibility of preparing nanocapsules and nanoemulsions using tea tree oil as oily phase aiming to protect its volatilization was evaluated, and the results showed that the inclusion of the oil in nanocapules showed higher protection against VOLATILization.
Abstract: The goal of this study was to evaluate the feasibility of preparing nanocapsules and nanoemulsions using tea tree oil as oily phase aiming to protect its volatilization. The nanostructures presented nanometric mean size (160-220 nm) with a polydispersity index below 0.25 and negative zeta potential. The pH values were 6.43 ± 0.37 and 5.98 ± 0.00 for nanoemulsions and nanocapsules, respectively. The oil content after preparation was 96%. The inclusion of tea tree oil in nanocapsules showed higher protection against volatilization. The analysis of mean size and polydispersity index of formulations presented no significant alteration during the storage time.
TL;DR: The hypothesis that MeHg induces neurotoxicity via oxidative stress mechanisms, and that these effects are attenuated by the antioxidant, ebselen is tested, and the protective effects elicited by ebselsen reinforce the idea that organic selenocompounds represent promising strategies to counteract MeHG-induced neurotoxicity.
Abstract: Methylmercury (MeHg) preferentially accumulates in glia of the central nervous system (CNS), but its toxic mechanisms have yet to be fully recognized. In the present study, we tested the hypothesis that MeHg induces neurotoxicity via oxidative stress mechanisms, and that these effects are attenuated by the antioxidant, ebselen. Rat neonatal primary cortical astrocytes were pretreated with or without 10 μM ebselen for 2 h followed by MeHg (0, 1, 5, and 10 μM) treatments. MeHg-induced changes in astrocytic [3H]-glutamine uptake were assessed along with changes in mitochondrial membrane potential (ΔΨm), using the potentiometric dye tetramethylrhodamine ethyl ester (TMRE). Western blot analysis was used to detect MeHg-induced ERK (extracellular-signal related kinase) phosphorylation and caspase-3 activation. MeHg treatment significantly decreased (p