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Find video protocols related to scientific articles indexed in Pubmed.
Proteomic white adipose tissue analysis of obese mice fed with a high-fat diet and treated with oral angiotensin-(1-7).
Peptides
PUBLISHED: 08-04-2014
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Angiotensin-(1-7) has been described as a new potential therapeutic tool for the treatment and prevention of metabolic disorders by regulating several pathways in visceral white adipose tissue (vWAT). The aim of this study was to access the proteins differentially regulated by Ang-(1-7) using proteomic analysis of visceral adipose tissue. Male mice were divided into three groups and fed for 60 days, with each group receiving one of the following diets: standard diet+HP?CD (ST), high fat diet+HP?CD (HFD) and high fat diet+Ang-(1-7)/HP?CD (HFD+Ang-(1-7)). Body weight, fat weight and food intake were measured. At the end of treatment, Ang-(1-7) induced a decrease in body and fat weight. Differential proteomic analysis using two-dimensional electrophoresis (2-DE) combined with mass spectrometry were performed. Results of protein mapping of mesenteric adipose tissue using 2-DE revealed the presence of about 450 spots in each gel (n=3/treatment) with great reproducibility (>70%). Image analysis and further statistical analysis allowed the detection and identification of eight proteins whose expression was modulated in response to HFD when compared to ST. Among these, two proteins showed a sensitive response to Ang-(1-7) treatment (eno1 and aldehyde dehydrogenase). In addition, three proteins were expressed statistically different between HFD+Ang-(1-7) and HFD groups, and four proteins were modulated compared to standard diet. In conclusion, comparative proteomic analysis of a mice model of diet-induced obesity allowed us to outline possible pathways involved in the response to Ang-(1-7), suggesting that Ang-(1-7) may be a useful tool for the treatment of metabolic disorders.
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Resveratrol attenuates hepatic steatosis in high-fat fed mice by decreasing lipogenesis and inflammation.
Nutrition
PUBLISHED: 07-03-2014
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Resveratrol (RSV) is the most studied natural compound that activates sirtuins, which produce beneficial metabolic effects on lipid and glucose metabolism. The aim of the present study was to investigate the role of resveratrol in preventing nonalcoholic fatty liver disease (NAFLD) and expression of liver inflammatory markers in mice treated with a high-fat diet.
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Angiotensin 1-7: a peptide for preventing and treating metabolic syndrome.
Peptides
PUBLISHED: 05-06-2014
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Angiotensin-(1-7) is one of the most important active peptides of the renin-angiotensin system (RAS) with recognized cardiovascular relevance; however several studies have shown the potential therapeutic role of Ang-(1-7) on treating and preventing metabolic disorders as well. This peptide achieves a special importance considering that in the last few decades obesity and metabolic syndrome (MS) have become a growing worldwide health problem. Angiotensin (Ang) II is the most studied component of RAS and is increased during obesity, diabetes and dyslipidemia (MS); some experimental evidence has shown that Ang II modulates appetite and metabolism as well as mechanisms that induce adipose tissue growth and metabolism in peripheral organs. Recent articles demonstrated that Ang-(1-7)/Mas axis modulates lipid and glucose metabolism and counterregulates the effects of Ang II. Based on these data, angiotensin-converting enzyme 2 (ACE2)/Ang-(1-7)/Mas pathway activation have been advocated as a new tool for treating metabolic diseases. This review summarizes the new evidence from animal and human experiments indicating the use of Ang-(1-7) in prevention and treatment of obesity and metabolic disorders.
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[Influence of socioeconomic factors on the quality of life of elderly hypertensive individuals].
Cien Saude Colet
PUBLISHED: 04-05-2014
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This study sought to evaluate the association between socioeconomic variables and the quality of life of elderly hypertensive patients treated under the Family Health Program in the city of Montes Claros, Minas Gerais, Brazil. An analytical cross study was conducted in a representative sample of 294 elderly hypertensive patients. Data were collected using a questionnaire on socioeconomic characteristics and quality of life (MINICHAL). The data were analyzed using the nonparametric Mann-Whitney and Kuskall-Wallis tests. The results showed that marital status, religion and education affect the quality of life of elderly hypertensive patients in a statistically significant way. Elderly hypertensive patients who were single/divorced/widowed, evangelical, spiritualist and belonging to other religious bodies, illiterate achieved lower scores in terms of quality of life. For the remaining variables, there was no statistical association. The conclusion, drawn is that socioeconomic factors such as marital status, education and religion influence the quality of life of elderly hypertensive patients.
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Mitochondria: biological roles in platelet physiology and pathology.
Int. J. Biochem. Cell Biol.
PUBLISHED: 02-01-2014
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Mitochondria are key regulators of cellular energy and redox metabolism, also playing a central role in cell signaling and death pathways. A number of processes occur within mitochondria, including redox-dependent ATP synthesis by oxidative phosphorylation and reactive oxygen species production. Mitochondrial permeability transition is a reversible process that may lead to cell death and is regulated by calcium and reactive oxygen species. Functional mitochondria are present in platelets, and evidence has demonstrated the direct involvement of these organelles in cellular ATP production, redox balance, as well as in platelet activation and apoptosis. Here, we review aspects of platelet physiology in which mitochondria are involved, as well as assess their function as new tools for studying a number of human diseases.
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[Risk behavior for the health of students at the State University of North Paraná, Brazil--proposal for online intervention].
Cien Saude Colet
PUBLISHED: 01-30-2014
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Getting to know the lifestyles of university students provides important input for possible decision-making for the implementation of intervention programs within the university environment. The objective of this study was to analyze the prevalence of risk behaviors to health in a representative sample of UENP students and, in accordance with the information obtained, indicate specific actions using means that can assist in reducing such behaviors. The survey of the main risk factors for the health of the population in question was performed by database analysis. The orientation was conducted through social networks, with online control over access to and interactions with members of the networks using information made available by the research. More than 200 messages were posted, trying to put this population on the path towards factors related to healthy habits. A viewing average of 471.2 ± 128.16 people accessed the page and an average of 12,915.07 ± 6,517.45 people saw the posts per week. Given the above, we suggest actions in UENP to encourage healthy habits, and the social networks proved to be a viable tool for this though other media may be offered, seeking to encourage this population to adopt a more active and health lifestyle.
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Mechanisms of acute kidney injury induced by experimental Lonomia obliqua envenomation.
Arch. Toxicol.
PUBLISHED: 01-19-2014
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Lonomia obliqua caterpillar envenomation causes acute kidney injury (AKI), which can be responsible for its deadly actions. This study evaluates the possible mechanisms involved in the pathogenesis of renal dysfunction. To characterize L. obliqua venom effects, we subcutaneously injected rats and examined renal functional, morphological and biochemical parameters at several time points. We also performed discovery-based proteomic analysis to measure protein expression to identify molecular pathways of renal disease. L. obliqua envenomation causes acute tubular necrosis, which is associated with renal inflammation; formation of hematic casts, resulting from intravascular hemolysis; increase in vascular permeability and fibrosis. The dilation of Bowman's space and glomerular tuft is related to fluid leakage and intra-glomerular fibrin deposition, respectively, since tissue factor procoagulant activity increases in the kidney. Systemic hypotension also contributes to these alterations and to the sudden loss of basic renal functions, including filtration and excretion capacities, urinary concentration and maintenance of fluid homeostasis. In addition, envenomed kidneys increase the expression of proteins involved in cell stress, inflammation, tissue injury, heme-induced oxidative stress, coagulation and complement system activation. Finally, the localization of the venom in renal tissue agrees with morphological and functional alterations, suggesting also a direct nephrotoxic activity. In conclusion, the mechanisms of L. obliqua-induced AKI are complex involving mainly glomerular and tubular functional impairment and vascular alterations. These results are important to understand the mechanisms of renal injury and may suggest more efficient ways to prevent or attenuate the pathology of Lonomia's envenomation.
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Resveratrol increases brown adipose tissue thermogenesis markers by increasing SIRT1 and energy expenditure and decreasing fat accumulation in adipose tissue of mice fed a standard diet.
Eur J Nutr
PUBLISHED: 01-13-2014
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Adipose tissue is central to the regulation of energy balance. Two functionally different fat pads are present in mammals: white adipose tissue, the primary site of triglyceride storage, and brown adipose tissue (BAT), which is specialized in heat production. In this context, new strategies capable of modulating the development and function of white and BAT become relevant. In the present study, we analyzed the influence of resveratrol (sirtuin activator) on energy balance and the expression of thermogenesis markers.
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Cross talk between angiotensin-(1-7)/Mas axis and sirtuins in adipose tissue and metabolism of high-fat feed mice.
Peptides
PUBLISHED: 01-07-2014
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Angiotensin-(1-7) and resveratrol have been described as new potential therapeutic tools on treating and preventing metabolic disorders. In the present study we aimed to evaluate the effect of an oral formulation of angiotensin-(1-7) [Ang-(1-7)] included in HPB-cyclodextrin and resveratrol (RSV), in modulation of sirtuin and renin-angiotensin system (RAS) in adipose tissue of mice treated with a high-fat diet (HFD). We observed that HFD+Ang-(1-7) and HFD+RSV groups presented marked decrease in the adipose tissue mass. Furthermore, these animals showed improved insulin-sensitivity and glucose tolerance as well as lower plasma levels of fasting glucose and lipids. The RT-PCR analysis revealed decreased expression of ACE and an increase of ACE2 [Ang-(1-7) marker] in group treated with resveratrol and also an increased expression of SIRT1 in groups that received Ang-(1-7). We showed for the first time that improved metabolic profile is associated with increased expression of GLUT4 and high expression of AMPK/FOXO1/PPAR-? pathway in adipose-tissue. Finally, adipocyte primary cell-culture incubated with and without sirtuin and Ang-(1-7)/Mas antagonists pointed out for a cross-talking between RAS and sirtuins. We conclude that oral administration of Ang-(1-7) and RSV improved metabolic profile through a cross-modulation between RAS and Sirtuins.
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Aspects of the behavior and activity rhythms of Rowlandius potiguar (Schizomida: Hubbardiidae).
PLoS ONE
PUBLISHED: 01-01-2014
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Although organisms of the order Schizomida are not widely distributed in caves throughout the world, they can, eventually, be abundant in certain regions, becoming a major faunal element in some caves. The majority of works on this order includes species descriptions, with rare references to behavioral aspects. As such, the present study describes the behavioral repertoire, and the activity and feeding periods of Rowlandius potiguar (Schizomida: Hubbardiidae) in the laboratory. The specimens were maintained in a terrarium, in an aphotic room, with temperature and humidity levels similar to the cave of origin. We used the focal-animal and ad libitum methods to describe behavior with qualitative and quantitative evaluations of behavioral acts. We witnessed nineteen behavioral acts, which is considered representative for observations in captivity. Two activity periods were observed: between 10 a.m. and 4 p.m. and between 10 p.m. and 4 a.m., characterizing an ultradian rhythm. In adaptive terms, this condition may be important for population maintenance in oligotrophic environments such as caverns. Necrophagy and cannibalism were also registered and could have been selected in the subterranean environment due to oligotrophy. The observation of rare and unprecedented behavior in this group, as well as the presence of rhythmicity in activity patterns, contribute to a better understanding of the ecological aspects of the species of this still little known Order.
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Unsaturated glycerophospholipids mediate heme crystallization: biological implications for hemozoin formation in the kissing bug Rhodnius prolixus.
PLoS ONE
PUBLISHED: 01-01-2014
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Hemozoin (Hz) is a heme crystal produced by some blood-feeding organisms, as an efficient way to detoxify heme derived from hemoglobin digestion. In the triatomine insect Rhodnius prolixus, Hz is essentially produced by midgut extracellular phospholipid membranes known as perimicrovillar membranes (PMVM). Here, we investigated the role of commercial glycerophospholipids containing serine, choline and ethanolamine as headgroups and R. prolixus midgut lipids (RML) in heme crystallization. All commercial unsaturated forms of phospholipids, as well as RML, mediated fast and efficient ?-hematin formation by means of two kinetically distinct mechanisms: an early and fast component, followed by a late and slow one. The fastest reactions observed were induced by unsaturated forms of phosphatidylethanolamine (uPE) and phosphatidylcholine (uPC), with half-lives of 0.04 and 0.7 minutes, respectively. ?-hematin crystal morphologies were strikingly distinct among groups, with uPE producing homogeneous regular brick-shaped crystals. Interestingly, uPC-mediated reactions resulted in two morphologically distinct crystal populations: one less representative group of regular crystals, resembling those induced by uPE, and the other largely represented by crystals with numerous sharp edges and tapered ends. Heme crystallization reactions induced by RML were efficient, with a heme to ?-hematin conversion rate higher than 70%, but clearly slower (t1/2 of 9.9-17.7 minutes) than those induced by uPC and uPE. Interestingly, crystals produced by RML were homogeneous in shape and quite similar to those mediated by uPE. Thus, ?-hematin formation can be rapidly and efficiently induced by unsaturated glycerophospholipids, particularly uPE and uPC, and may play a role on biological heme crystallization in R. prolixus midgut.
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Sirtuins and cancer: new insights and cell signaling.
Cancer Invest.
PUBLISHED: 12-05-2013
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Sirtuins are involved in the control of the cell cycle and regulation of gene transcription. While some sirtuins have tumor suppressor effects, others regulate tumors metabolism. Within this perspective, the present article is a review of the current role of sirtuins in the etiology and physiopathology of cancer. Sirtuins show strong potential to become a valuable predictive and prognostic marker for cancer and are eligible as therapeutic targets for a variety of tumors. Investigation of new molecules able to modulate sirtuins activity must be encouraged.
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Platelets mediate increased endothelium permeability in dengue through NLRP3-inflammasome activation.
Blood
PUBLISHED: 09-05-2013
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Dengue is the most frequent hemorrhagic viral disease and re-emergent infection in the world. Although thrombocytopenia is characteristically observed in mild and severe forms of dengue, the role of platelet activation in dengue pathogenesis has not been fully elucidated. We hypothesize that platelets have major roles in inflammatory amplification and increased vascular permeability during severe forms of dengue. Here we investigate interleukin (IL)-1? synthesis, processing, and secretion in platelets during dengue virus (DV) infection and potential contribution of these events to endothelial permeability during infection. We observed increased expression of IL-1? in platelets and platelet-derived microparticles from patients with dengue or after platelet exposure to DV in vitro. We demonstrated that DV infection leads to assembly of nucleotide-binding domain leucine rich repeat containing protein (NLRP3) inflammasomes, activation of caspase-1, and caspase-1-dependent IL-1? secretion. Our findings also indicate that platelet-derived IL-1? is chiefly released in microparticles through mechanisms dependent on mitochondrial reactive oxygen species-triggered NLRP3 inflammasomes. Inflammasome activation and platelet shedding of IL-1?-rich microparticles correlated with signs of increased vascular permeability. Moreover, microparticles from DV-stimulated platelets induced enhanced permeability in vitro in an IL-1-dependent manner. Our findings provide new evidence that platelets contribute to increased vascular permeability in DV infection by inflammasome-dependent release of IL-1?.
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Silencing of maternal heme-binding protein causes embryonic mitochondrial dysfunction and impairs embryogenesis in the blood sucking insect Rhodnius prolixus.
J. Biol. Chem.
PUBLISHED: 08-28-2013
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The heme molecule is the prosthetic group of many hemeproteins involved in essential physiological processes, such as electron transfer, transport of gases, signal transduction, and gene expression modulation. However, heme is a pro-oxidant molecule capable of propagating reactions leading to the generation of reactive oxygen species. The blood-feeding insect Rhodnius prolixus releases enormous amounts of heme during host blood digestion in the midgut lumen when it is exposed to a physiological oxidative challenge. Additionally, this organism produces a hemolymphatic heme-binding protein (RHBP) that transports heme to pericardial cells for detoxification and to growing oocytes for yolk granules and as a source of heme for embryo development. Here, we show that silencing of RHBP expression in female fat bodies reduced total RHBP circulating in the hemolymph, promoting oxidative damage to hemolymphatic proteins. Moreover, RHBP knockdown did not cause reduction in oviposition but led to the production of heme-depleted eggs (white eggs). A lack of RHBP did not alter oocyte fecundation. However, produced white eggs were nonviable. Embryo development cellularization and vitellin yolk protein degradation, processes that normally occur in early stages of embryogenesis, were compromised in white eggs. Total cytochrome c content, cytochrome c oxidase activity, citrate synthase activity, and oxygen consumption, parameters that indicate mitochondrial function, were significantly reduced in white eggs compared with normal dark red eggs. Our results showed that reduction of heme transport from females to growing oocytes by RHBP leads to embryonic mitochondrial dysfunction and impaired embryogenesis.
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Determination of cocaine in postmortem human liver exposed to overdose. Application of an innovative and efficient extraction/clean up procedure and gas chromatography-mass spectrometry analysis.
J Chromatogr A
PUBLISHED: 06-25-2013
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A simple and efficient method was developed for the determination of cocaine in post-mortem samples of human liver via solid-liquid extraction with low temperature partitioning (SLE-LTP) and analysis by gas chromatography coupled to mass spectrometry (GC-MS). The extraction procedure was optimized by evaluating the influence of the following variables: pH of the extract, volume and composition of the extractor solvent, addition of a sorbent material (PSA: primary-secondary amine) and NaCl to clean up and increase the ionic strength of the extract. A bovine liver sample that was free of cocaine was used as a blank for the optimization of the SLE-LTP extraction procedure. The highest recovery was obtained when crushed bovine liver (2g) was treated with 2mL of ultrapure water plus 8mL of acetonitrile at physiological pH (7.4). The results also indicated no need for using PSA and NaCl. The complete analytical procedure was validated for the following figures of merit: selectivity, lower limit of quantification (LLOQ), calibration curve, recovery, precision and accuracy (for within-run and between-run experiments), matrix effect, dilution integrity and stability. The within-run and between-run precision (at four levels) varied from 2.1% to 9.4% and from 4.0% to 17.0%, respectively. A maximum deviation of 11.62% for the within-run and between-run accuracies in relation to the nominal concentrations was observed. Moreover, the LLOQ value for cocaine was 50.0ngg(-1) whereas no significant effects were noticed in the assays of dilution integrity and stability. To assess its overall performance, the optimized method was applied to the analysis of eight human liver samples collected from individuals who died due to the abusive consumption of cocaine. Due to the existence of a significant matrix effect, a blank human liver was used to construct a matrix-matched analytical curve. The concentrations of cocaine found in these samples ranged from 333.5 to 5969ngg(-1).
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[Degree of dependence of elderly residents in geriatric long-term care facilities in Montes Claros, MG].
Rev Gaucha Enferm
PUBLISHED: 06-21-2013
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This study aimed to identify the degree of dependence of institutionalized older adults in Montes Claros, Minas Gerais, Brazil. It consists of a cross-sectional descriptive study, developed in three non-profit geriatric long-term care facilities in this municipality. The sample was comprised of 125 older adults and data were collected with the use of the Katz Index. Data were presented by descriptive and bivariate analysis. Independence was observed in 41.6% (n = 52), partial dependence in 15.2% (n = 19) and total dependence in 43.2% (n = 54). The elderly have better ability to perform feeding (86.4%, n = 108) and transferring (67.2%, n = 84) activities. Thus, this study suggests the need for continuous monitoring to prevent functional disability in this population group.
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In vivo detection of free radicals in mouse septic encephalopathy using molecular MRI and immuno-spin trapping.
Free Radic. Biol. Med.
PUBLISHED: 06-20-2013
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Free radicals are known to play a major role in sepsis. Combined immuno-spin trapping and molecular magnetic resonance imaging (MRI) was used to detect in vivo and in situ levels of free radicals in murine septic encephalopathy after cecal ligation and puncture (CLP). DMPO (5,5-dimethyl pyrroline N-oxide) was injected over 6h after CLP, before administration of an anti-DMPO probe (anti-DMPO antibody bound to albumin-gadolinium-diethylene triamine pentaacetic acid-biotin MRI targeting contrast agent). In vitro assessment of the anti-DMPO probe in oxidatively stressed mouse astrocytes significantly decreased T1 relaxation (p < 0.0001) compared to controls. MRI detected the presence of anti-DMPO adducts via a substantial decrease in %T1 change within the hippocampus, striatum, occipital, and medial cortex brain regions (p < 0.01 for all) in septic animals compared to shams, which was sustained for over 60min (p < 0.05 for all). Fluorescently labeled streptavidin was used to target the anti-DMPO probe biotin, which was elevated in septic brain, liver, and lungs compared to sham. Ex vivo DMPO adducts (qualitative) and oxidative products, including 4-hydroxynonenal and 3-nitrotyrosine (quantitative, p < 0.05 for both), were elevated in septic brains compared to shams. This is the first study that has reported on the detection of in vivo and in situ levels of free radicals in murine septic encephalopathy.
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Oral formulation of angiotensin-(1-7) improves lipid metabolism and prevents high-fat diet-induced hepatic steatosis and inflammation in mice.
Hypertension
PUBLISHED: 06-10-2013
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Angiotensin (Ang)-(1-7) has been described as an important tool on treating and preventing metabolic disorders. In this study, we aimed to evaluate the effect of an oral formulation of Ang-(1-7) included in hydroxypropyl?-cyclodextrin (HP?CD/Ang-[1-7]) on hepatic function, steatosis, and on liver inflammatory markers expression in mice treated with a high-fat diet. Male FVB/N mice were divided into 4 groups and fed for 60 days, with each group receiving 1 of the following diets: standard diet+HP?CD, standard diet+Ang-(1-7)/HP?CD, high-fat diet+HP?CD, or high-fat diet+Ang-[1-7]/HP?CD. Body weight, food intake, and blood parameters, such as total cholesterol, triglyceride, alaninetransaminases, and aspartate transaminases, were evaluated. Immunohistochemical analyses were performed for inflammatory markers tumor necrosis factor-? and interleukin-6. Expression of angiotensin converting enzyme, angiotensin-converting enzyme-2, interleukin-1?, tumor necrosis factor-?, interleukin-6, transforming growth factor-?, acetyl-CoA carboxylase, carbohydrate-responsive element-binding protein, peroxisome proliferator-activated receptor-?, and sterol regulatory element-binding proteins-1c was evaluated by quantitative real-time polymerase chain reaction. The major findings of our study included reduced liver fat mass and weight, decreased plasma total cholesterol, triglyceride, and alaninetransaminase enzyme levels in the oral Ang-(1-7)-treated groups compared with the control groups. These results were accompanied by a significant reduction in tumor necrosis factor-? and interleukin-6 mRNA expression in the liver. Analyses of liver adipogenesis-related genes by quantitative real-time polymerase chain reaction showed that acetyl-CoA carboxylase, peroxisome proliferator-activated receptor-?, and sterol regulatory element-binding proteins-1c mRNA expression were significantly suppressed. In conclusion, we observed that treatment with Ang-(1-7) improved metabolism and decreased proinflammatory profile and fat deposition in liver of mice.
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Gene expression modulation by paraquat-induced oxidative stress conditions in Paracoccidioides brasiliensis.
Fungal Genet. Biol.
PUBLISHED: 04-29-2013
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Paracoccidioides brasiliensis is a thermodimorphic fungus associated with paracoccidioidomycosis (PCM), the most common systemic mycosis in Latin America. The infection is initiated by inhalation of environmentally dispersed conidia produced by the saprophytic phase of the fungus. In the lungs, P. brasiliensis assumes the parasitic yeast form and must cope with the adverse conditions imposed by cells of the host immune system, which includes a harsh environment, highly concentrated in reactive oxygen species (ROS). In this work, we used the ROS-generating agent paraquat to experimentally simulate oxidative stress conditions in order to evaluate the stress-induced modulation of gene expression in cultured P. brasiliensis yeast cells, using a microarray hybridization approach. The large-scale evaluation inherent to microarray-based analyses identified 2070 genes differentially transcribed in response to paraquat exposure, allowing an integrated visualization of the major metabolic changes that constitute the systemic defense mechanism used by the fungus to overcome the deleterious effects of ROS. These include overexpression of detoxifying agents, as well as of molecular scavengers and genes involved in maintenance of the intracellular redox potential. Particularly noteworthy was to verify that the oxidative stress resistance mechanism of P. brasiliensis also involves coordinated overexpression of a series of genes responsible for chitin-biosynthesis, suggesting that this pathway may constitute a specific regulon. Further analyses aiming at confirming and understanding the mechanisms that control such regulon may provide interesting new targets for chemotherapeutic approaches against P. brasiliensis and other pathogenic fungi.
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Oral Angiotensin-(1-7) prevented obesity and hepatic inflammation by inhibition of resistin/TLR4/MAPK/NF-?B in rats fed with high-fat diet.
Peptides
PUBLISHED: 03-19-2013
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Obesity is characterized by a pro-inflammatory state commonly associated with type 2 diabetes and fat-liver disease. In the last few years, different studies pointed out the role of Angiotensin (Ang)-(1-7) in the metabolic regulation. The aim of the present study was to evaluate the effect of oral-administration of Ang-(1-7) in metabolism and inflammatory state of high-fat feed rats. Twenty-four male Sprague Dawley rats were randomized into three groups: High Fat Diet (HFD); Standard Diet (ST); High Fat Diet+Angiotensin-(1-7) [HFD+Ang-(1-7)]. Glycemic profile was evaluated by glucose tolerance and insulin sensitivity tests, plasmatic glucose and insulin. Cholesterol, HDL and triglycerides analyses presented lipidic profile. RT-PCR evaluated mRNA expression to ACE, ACE2, resistin, TLR4, IL-6, TNF-? and NF-?B genes. The main results showed that oral Ang-(1-7) decreased body weight and abdominal fat-mass. In addition, HFD+Ang-(1-7) treated rats presented enhanced glucose tolerance, insulin-sensitivity and decreased plasma-insulin levels, as well as a significant decrease in circulating lipid levels. These alterations were accompanied by a marked decreased expression of resistin, TLR4, ACE and increased ACE2 expression in liver. Furthermore, Ang-(1-7) decreases phosphorylation of MAPK and increases NF-?B expression. These alterations diminished expression of interleukin-6 and TNF-?, ameliorate inflammatory state in liver. In summary, the present study showed that oral-treatment with Ang-(1-7) in high-fat feed rats improved metabolism down-regulating resistin/TLR4/NF-?B-pathway.
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Exercise-induced cardioprotection is impaired by anabolic steroid treatment through a redox-dependent mechanism.
J. Steroid Biochem. Mol. Biol.
PUBLISHED: 02-25-2013
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High doses of anabolic androgenic steroids (AAS) impair the cardioprotective effects of exercise against ischemia/reperfusion (I/R) insult, possibly through cellular redox imbalance. Here, the effect of nandrolone decanoate (DECA) treatment on heart redox metabolism was investigated during I/R in sedentary and exercised rats. DECA treatment significantly reduced superoxide dismutase and glutathione reductase activities in exercised rats after heart reperfusion. Catalase and glutathione peroxidase activities were not affected by DECA in both sedentary and trained rats, regardless the I/R period. DECA also induced myocardial oxidative stress, as evidenced by the reduced levels of total reduced thiols after heart reperfusion in exercised rats treated with the anabolic steroid. These results indicate that cardiotoxic effects of supraphysiological doses of AAS involve reduced heart antioxidant capacity.
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Intergroup time bias and racialized social relations.
Pers Soc Psychol Bull
PUBLISHED: 12-05-2011
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Within the framework of intergroup relations, the authors analyzed the time people spent evaluating ingroup and outgroup members. They hypothesized that White participants take longer to evaluate White targets than Black targets. In four experiments, White participants were slower to form impressions of White than of Black people; that is, they showed an intergroup time bias (ITB). In Study 1 (N = 60), the ITB correlated with implicit prejudice and homogeneity. Study 2 (N = 60) showed that the ITB was independent of the type of trait in question (nonstereotypical vs. stereotypical). Study 3 (N = 100) demonstrated that ITB correlates with racism measured 3 months beforehand, is independent of motivation to control prejudice, and is not an epiphenomenon of homogeneity. In Study 4 (N = 40) participants not only showed the ITB in a racialized social context but also displayed it following a minimal group manipulation.
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A comparative assessment of mitochondrial function in epimastigotes and bloodstream trypomastigotes of Trypanosoma cruzi.
J. Bioenerg. Biomembr.
PUBLISHED: 08-09-2011
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Trypanosoma cruzi is a hemoflagellate protozoan that causes Chagas disease. The life cycle of T. cruzi is complex and involves different evolutive forms that have to encounter different environmental conditions provided by the host. Herein, we performed a functional assessment of mitochondrial metabolism in the following two distinct evolutive forms of T. cruzi: the insect stage epimastigote and the freshly isolated bloodstream trypomastigote. We observed that in comparison to epimastigotes, bloodstream trypomastigotes facilitate the entry of electrons into the electron transport chain by increasing complex II-III activity. Interestingly, cytochrome c oxidase (CCO) activity and the expression of CCO subunit IV were reduced in bloodstream forms, creating an "electron bottleneck" that favored an increase in electron leakage and H(2)O(2) formation. We propose that the oxidative preconditioning provided by this mechanism confers protection to bloodstream trypomastigotes against the host immune system. In this scenario, mitochondrial remodeling during the T. cruzi life cycle may represent a key metabolic adaptation for parasite survival in different hosts.
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Influence of inflammation on parasitism and area of experimental amoebic liver abscess: an immunohistochemical and morphometric study.
Parasit Vectors
PUBLISHED: 02-28-2011
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The influence of inflammation on the number of trophozoites and on the murine amoebic liver abscess area following infection with Entamoeba histolytica and E. dispar was evaluated. Immunohistochemistry and digital morphometry were used to identify and quantify the trophozoites, neutrophils, macrophages, and lesions. Positive correlation was observed between the number of trophozoites and inflammatory cells. A significant decrease in parasitism and inflammation in groups treated with dexamethasone was observed. The scarceness or absence of trophozoites in the treated groups suggest the importance of the inflammatory response in the production of amoebic hepatic abscesses in spite of the inherent virulence of the parasite being decisive in the establishment of the lesion.
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Bioenergetic failure of human peripheral blood monocytes in patients with septic shock is mediated by reduced F1Fo adenosine-5-triphosphate synthase activity.
Crit. Care Med.
PUBLISHED: 02-22-2011
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Increasing evidence points to the role of mitochondrial dysfunction in the pathogenesis of sepsis. Previous data indicate that mitochondrial function is affected in monocytes from septic patients, but the underlying mechanisms and the impact of these changes on the patients outcome are unknown. We aimed to determine the mechanisms involved in mitochondrial dysfunction in peripheral blood mononuclear cells from patients with septic shock.
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On the mechanisms involved in biological heme crystallization.
J. Bioenerg. Biomembr.
PUBLISHED: 02-09-2011
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Blood-feeding organisms digest hemoglobin, releasing large quantities of heme inside their digestive tracts. Free heme is very toxic, and these organisms have evolved several mechanisms to protect against its deleterious effects. One of these adaptations is the crystallization of heme into the dark-brown pigment hemozoin (Hz). Here we review the process of Hz formation, focusing on organisms other than Plasmodium that have contributed to a better understanding of heme crystallization. Hemozoin has been found in several distinct classes of organisms including protozoa, helminths and insects and Hz formation is the predominant form of heme detoxification. The available evidence indicates that amphiphilic structures such as phospholipid membranes and lipid droplets accompanied by specific proteins play a major role in heme crystallization. Because this process is specific to a number of blood-feeding organisms and absent in their hosts, Hz formation is an attractive target for the development of novel drugs to control illnesses associated with these hematophagous organisms.
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Heme-induced ROS in Trypanosoma cruzi activates CaMKII-like that triggers epimastigote proliferation. One helpful effect of ROS.
PLoS ONE
PUBLISHED: 02-03-2011
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Heme is a ubiquitous molecule that has a number of physiological roles. The toxic effects of this molecule have been demonstrated in various models, based on both its pro-oxidant nature and through a detergent mechanism. It is estimated that about 10 mM of heme is released during blood digestion in the blood-sucking bugs midgut. The parasite Trypanosoma cruzi, the agent of Chagas disease, proliferates in the midgut of the insect vector; however, heme metabolism in trypanosomatids remains to be elucidated. Here we provide a mechanistic explanation for the proliferative effects of heme on trypanosomatids. Heme, but not other porphyrins, induced T. cruzi proliferation, and this phenomenon was accompanied by a marked increase in reactive oxygen species (ROS) formation in epimastigotes when monitored by ROS-sensitive fluorescent probes. Heme-induced ROS production was time- and concentration-dependent. In addition, lipid peroxidation and the formation of 4-hydroxy-2-nonenal (4-HNE) adducts with parasite proteins were increased in epimastigotes in the presence of heme. Conversely, the antioxidants urate and GSH reversed the heme-induced ROS. Urate also decreased parasite proliferation. Among several protein kinase inhibitors tested only specific inhibitors of CaMKII, KN93 and Myr-AIP, were able to abolish heme-induced ROS formation in epimastigotes leading to parasite growth impairment. Taken together, these data provide new insight into T. cruzi- insect vector interactions: heme, a molecule from the blood digestion, triggers epimastigote proliferation through a redox-sensitive signalling mechanism.
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Low triglyceride levels are associated with a better metabolic control in patients with type 1 diabetes.
Diabetol Metab Syndr
PUBLISHED: 02-02-2011
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Although it is well known in the literature that high triglyceride serum (TG) levels can jeopardize the metabolic control, little is known about the influence of low TG on type 1 diabetes patients (T1D). The aim of this study is to investigate the distribution of TG serum levels in individuals with T1D and its relationship with metabolic control.
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Energy metabolism affects susceptibility of Anopheles gambiae mosquitoes to Plasmodium infection.
Insect Biochem. Mol. Biol.
PUBLISHED: 01-26-2011
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Previous studies showed that Anopheles gambiae L3-5 females, which are refractory (R) to Plasmodium infection, express higher levels of genes involved in redox-metabolism and mitochondrial respiration than susceptible (S) G3 females. Our studies revealed that R females have reduced longevity, faster utilization of lipid reserves, impaired mitochondrial state-3 respiration, increased rate of mitochondrial electron leak and higher expression levels of several glycolytic enzyme genes. Furthermore, when state-3 respiration was reduced in S females by silencing expression of the adenine nucleotide translocator (ANT), hydrogen peroxide generation was higher and the mRNA levels of lactate dehydrogenase increased in the midgut, while the prevalence and intensity of Plasmodium berghei infection were significantly reduced. We conclude that there are broad metabolic differences between R and S An. gambiae mosquitoes that influence their susceptibility to Plasmodium infection.
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Analysis of socio-demographic and systemic health factors and the normative conditions of oral health care in a population of the Brazilian elderly.
Gerodontology
PUBLISHED: 11-17-2010
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To investigate the association of socio-demographic and systemic health factors according to the normative conditions of oral health care (dental caries, edentulism, periodontal disease and oral mucosal lesion) in elderly individuals.
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Increase on the initial soluble heme levels in acidic conditions is an important mechanism for spontaneous heme crystallization in vitro.
PLoS ONE
PUBLISHED: 08-06-2010
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Hemozoin (Hz) is a heme crystal that represents a vital pathway for heme disposal in several blood-feeding organisms. Recent evidence demonstrated that ?-hematin (?H) (the synthetic counterpart of Hz) formation occurs under physiological conditions near synthetic or biological hydrophilic-hydrophobic interfaces. This seems to require a heme dimer acting as a precursor of Hz crystals that would be formed spontaneously in the absence of the competing water molecules bound to the heme iron. Here, we aimed to investigate the role of medium polarity on spontaneous ?H formation in vitro.
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Cognitive dysfunction is sustained after rescue therapy in experimental cerebral malaria, and is reduced by additive antioxidant therapy.
PLoS Pathog.
PUBLISHED: 05-25-2010
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Neurological impairments are frequently detected in children surviving cerebral malaria (CM), the most severe neurological complication of infection with Plasmodium falciparum. The pathophysiology and therapy of long lasting cognitive deficits in malaria patients after treatment of the parasitic disease is a critical area of investigation. In the present study we used several models of experimental malaria with differential features to investigate persistent cognitive damage after rescue treatment. Infection of C57BL/6 and Swiss (SW) mice with Plasmodium berghei ANKA (PbA) or a lethal strain of Plasmodium yoelii XL (PyXL), respectively, resulted in documented CM and sustained persistent cognitive damage detected by a battery of behavioral tests after cure of the acute parasitic disease with chloroquine therapy. Strikingly, cognitive impairment was still present 30 days after the initial infection. In contrast, BALB/c mice infected with PbA, C57BL6 infected with Plasmodium chabaudi chabaudi and SW infected with non lethal Plasmodium yoelii NXL (PyNXL) did not develop signs of CM, were cured of the acute parasitic infection by chloroquine, and showed no persistent cognitive impairment. Reactive oxygen species have been reported to mediate neurological injury in CM. Increased production of malondialdehyde (MDA) and conjugated dienes was detected in the brains of PbA-infected C57BL/6 mice with CM, indicating high oxidative stress. Treatment of PbA-infected C57BL/6 mice with additive antioxidants together with chloroquine at the first signs of CM prevented the development of persistent cognitive damage. These studies provide new insights into the natural history of cognitive dysfunction after rescue therapy for CM that may have clinical relevance, and may also be relevant to cerebral sequelae of sepsis and other disorders.
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[Catalase activity in lung, kidney and small bowel non-ischemic in rats after intestinal reperfusion].
Rev Col Bras Cir
PUBLISHED: 04-24-2010
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This study aimed to assess the catalase activity after ischemia and reperfusion and to study the changes of this antioxidant in organs located far from the initial insult.
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Bioimaging of copper alterations in the aging mouse brain by autoradiography, laser ablation inductively coupled plasma mass spectrometry and immunohistochemistry.
Metallomics
PUBLISHED: 04-01-2010
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Copper may play an important role in the brain in aging and neurodegenerative diseases. We compare the active Cu uptake, Cu-containing enzyme levels, and total Cu distribution in the brains of young and aging mice. (67)Cu was administered intravenously to 2, 7-9, and 14 month old mice. Active uptake of (67)Cu in the brain was measured at 24 h by digital phosphor autoradiography. Cerebral superoxide dismutase-1 (SOD-1) and cytochrome-C oxidase subunit-1 (CCO-1) levels were analyzed by immunohistochemistry. The total Cu distribution in brain section was determined by imaging laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). In aging mice, active (67)Cu uptake and SOD-1 levels were significantly decreased in the brain, whereas blood (67)Cu and CCO-1 levels were similar for all mice, irrespective of age. Paradoxically, global Cu cerebral content was increased in aged mice, suggesting that regulation of active Cu uptake by the brain may be linked to total Cu levels in an attempt to maintain Cu homeostasis. However, focal areas of both decreased Cu uptake and Cu content were noted in the striatum and ventral cortex in aging mice. These focal areas of Cu deficit correspond to the regions of greatest reduction in SOD-1 in the aged mice. In aging, dysregulated Cu homeostasis may result in decreased SOD-1 levels, which may contribute to oxidative vulnerability of the aging brain. This study illustrates the importance of a multi-modality approach in studying the biodistribution and homeostasis of Cu in the brain.
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Transcriptome analysis of the phytobacterium Xylella fastidiosa growing under xylem-based chemical conditions.
J. Biomed. Biotechnol.
PUBLISHED: 03-15-2010
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Xylella fastidiosa is a xylem-limited bacterium responsible for important plant diseases, like citrus-variegated chlorosis (CVC) and grapevine Pierces disease (PD). Interestingly, in vitro growth of X. fastidiosa in chemically defined media that resemble xylem fluid has been achieved, allowing studies of metabolic processes used by xylem-dwelling bacteria to thrive in such nutrient-poor conditions. Thus, we performed microarray hybridizations to compare transcriptomes of X. fastidiosa cells grown in 3G10-R, a medium that resembles grape sap, and in Periwinkle Wilt (PW), the complex medium traditionally used to cultivate X. fastidiosa. We identified 299 transcripts modulated in response to growth in these media. Some 3G10R-overexpressed genes have been shown to be upregulated in cells directly isolated from infected plants and may be involved in plant colonization, virulence and environmental competition. In contrast, cells cultivated in PW show a metabolic switch associated with increased aerobic respiration and enhanced bacterial growth rates.
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On the physico-chemical and physiological requirements of hemozoin formation promoted by perimicrovillar membranes in Rhodnius prolixus midgut.
Insect Biochem. Mol. Biol.
PUBLISHED: 01-07-2010
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Triatomine insects are obligatory blood-feeders that detoxify most of the hemoglobin-derived heme through its crystallization into hemozoin (Hz). Previous evidence demonstrates the key role of midgut perimicrovillar membranes (PMVM) on heme crystallization in triatomines. Here, we investigated some of the physico-chemical and physiological aspects of heme crystallization induced by Rhodnius prolixus PMVM. Hz formation in vitro proceeded optimally at pH 4.8 and 28 degrees C, apparently involving three kinetically distinct mechanisms along this process. Furthermore, the insect feeding status and age affected PMVM-induced heme crystallization whereas pharmacological blockage of PMVM formation by azadirachtin, reduced hemoglobin digestion and Hz formation in vivo. Mössbauer spectrometry analyses of R. prolixus midgut showed that Hz represents the only measurable iron species found four days after a blood meal. Autocatalytic heme crystallization to Hz is revealed to be an inefficient process and this conversion is further reduced as the Hz concentration increases. Also, PMVM-derived lipids were able to induce rapid Hz formation, regardless of the diet composition. These results indicate that PMVM-driven Hz formation in R. prolixus midgut occurs at physiologically relevant physico-chemical conditions and that lipids derived from this structure play an important role in heme crystallization.
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Sepsis-associated encephalopathy: a magnetic resonance imaging and spectroscopy study.
J. Cereb. Blood Flow Metab.
PUBLISHED: 10-21-2009
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Brain dysfunction is frequently observed in sepsis as a consequence of changes in cerebral structure and metabolism, resulting in worse outcome and reduced life-quality of surviving patients. However, the mechanisms of sepsis-associated encephalopathy development and a better characterization of this syndrome in vivo are lacking. Here, we used magnetic resonance imaging (MRI) techniques to assess brain morphology and metabolism in a murine sepsis model (cecal ligation and puncture, CLP). Sham-operated and CLP mice were subjected to a complete MRI session at baseline, 6 and 24 h after surgery. Accumulation of vasogenic edematic fluid at the base of the brain was observed in T(2)-weighted image at 6 and 24 h after CLP. Also, the water apparent diffusion coefficients in both hippocampus and cortex were decreased, suggesting a cytotoxic edema in brains of nonsurvival septic animals. Moreover, the N-acetylaspartate/choline ratio was reduced in brains of septic mice, indicating neuronal damage. In conclusion, noninvasive assessment by MRI allowed the identification of new aspects of brain damage in sepsis, including cytotoxic and vasogenic edema as well as neuronal damage. These findings highlight the potential applications of MRI techniques for the diagnostic and therapeutic studies in sepsis.
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Reactive oxygen species production by potato tuber mitochondria is modulated by mitochondrially bound hexokinase activity.
Plant Physiol.
PUBLISHED: 05-15-2009
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Potato tuber (Solanum tuberosum) mitochondria (PTM) have a mitochondrially bound hexokinase (HK) activity that exhibits a pronounced sensitivity to ADP inhibition. Here we investigated the role of mitochondrial HK activity in PTM reactive oxygen species generation. Mitochondrial HK has a 10-fold higher affinity for glucose (Glc) than for fructose (KMGlc=140 microM versus KMFrc=1,375 microM). Activation of PTM respiration by succinate led to an increase in hydrogen peroxide (H2O2) release that was abrogated by mitochondrial HK activation. Mitochondrial HK activity caused a decrease in the mitochondrial membrane potential and an increase in oxygen consumption by PTM. Inhibition of Glc phosphorylation by mannoheptulose or GlcNAc induced a rapid increase in H2O2 release. The blockage of H2O2 release sustained by Glc was reverted by oligomycin and atractyloside, indicating that ADP recycles through the adenine nucleotide translocator and F0F1ATP synthase is operative during the mitochondrial HK reaction. Inhibition of mitochondrial HK activity by 60% to 70% caused an increase of 50% in the maximal rate of H2O2 release. Inhibition in H2O2 release by mitochondrial HK activity was comparable to, or even more potent, than that observed for StUCP (S. tuberosum uncoupling protein) activity. The inhibition of H2O2 release in PTM was two orders of magnitude more selective for the ADP produced from the mitochondrial HK reaction than for that derived from soluble yeast (Saccharomyces cerevisiae) HK. Modulation of H2O2 release and oxygen consumption by Glc and mitochondrial HK inhibitors in potato tuber slices shows that hexoses and mitochondrial HK may act as a potent preventive antioxidant mechanism in potato tubers.
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Blood-feeding induces reversible functional changes in flight muscle mitochondria of Aedes aegypti mosquito.
PLoS ONE
PUBLISHED: 04-27-2009
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Hematophagy poses a challenge to blood-feeding organisms since products of blood digestion can exert cellular deleterious effects. Mitochondria perform multiple roles in cell biology acting as the site of aerobic energy-transducing pathways, and also an important source of reactive oxygen species (ROS), modulating redox metabolism. Therefore, regulation of mitochondrial function should be relevant for hematophagous arthropods. Here, we investigated the effects of blood-feeding on flight muscle (FM) mitochondria from the mosquito Aedes aegypti, a vector of dengue and yellow fever.
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On the fate of extracellular hemoglobin and heme in brain.
J. Cereb. Blood Flow Metab.
PUBLISHED: 04-01-2009
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Intracerebral hemorrhage (ICH) is a major cause of disability in adults worldwide. The pathophysiology of this syndrome is complex, involving both inflammatory and redox components triggered by the extravasation of blood into the cerebral parenchyma. Hemoglobin, heme, and iron released therein seem be important in the brain damage observed in ICH. However, there is a lack of information concerning hemoglobin traffic and metabolism in brain cells. Here, we investigated the fate of hemoglobin and heme in cultured neurons and astrocytes, as well as in the cortex of adult rats. Hemoglobin was made traceable by conjugation to Alexa 488, whereas a fluorescent heme analogue (tin-protoporphyrin IX) was prepared to allow heme tracking. Using fluorescence microscopy we observed that neurons were more efficient in uptake hemoglobin and heme than astrocytes. Exposure of cortical neurons to hemoglobin or heme resulted in an oxidative stress condition. Viability assays showed that neurons were more susceptible to both hemoglobin and heme toxicity than astrocytes. Together, these results show that neurons, rather than astrocytes, preferentially take up hemoglobin-derived products, indicating that these cells are actively involved in the ICH-associated brain damage.
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The effects on Trypanosoma cruzi of novel synthetic naphthoquinones are mediated by mitochondrial dysfunction.
Free Radic. Biol. Med.
PUBLISHED: 03-24-2009
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Despite ongoing efforts, the current treatment for Chagas disease is still unsatisfactory, mainly because of the severe side effects and variable efficacy of the available nitroheterocycles. Our group has been assaying natural quinones isolated from Brazilian flora, and their derivatives, as alternative chemotherapeutic agents against Trypanosoma cruzi. From C-allyl lawsone three naphthofuranquinones were synthesized, which were active against trypomastigotes and epimastigotes. Here, we further investigated the activity and the mechanisms of action of these quinones. They exhibited powerful effects on intracellular amastigotes, presenting low toxicity to the host cells. Ultrastructural analyses of treated epimastigotes and trypomastigotes indicated a potent effect of the three naphthofuranquinones on the parasite mitochondrion, which appeared drastically swollen and with a washed-out matrix profile. Fluorescence-activated cell sorting analysis of rhodamine 123-stained T. cruzi showed that the three naphthofuranquinones caused a potent dose-dependent collapse of the mitochondrial membrane potential, especially in the epimastigote form. Naphthofuranquinones also decreased specifically mitochondrial complex I-III activity in both epimastigotes and trypomastigotes, parallel to a reduction in succinate-induced oxygen consumption. Mitochondrial hydrogen peroxide formation was also increased in epimastigotes after treatment with the naphthofuranquinones. Our results indicate that the trypanocidal action of the naphthofuranquinones is associated with mitochondrial dysfunction, leading to increased reactive oxygen species generation and parasite death.
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Interference with hemozoin formation represents an important mechanism of schistosomicidal action of antimalarial quinoline methanols.
PLoS Negl Trop Dis
PUBLISHED: 02-19-2009
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The parasitic trematode Schistosoma mansoni is one of the major causative agents of human schistosomiasis, which afflicts 200 million people worldwide. Praziquantel remains the main drug used for schistosomiasis treatment, and reliance on the single therapy has been prompting the search for new therapeutic compounds against this disease. Our group has demonstrated that heme crystallization into hemozoin (Hz) within the S. mansoni gut is a major heme detoxification route with lipid droplets involved in this process and acting as a potential chemotherapeutical target. In the present work, we investigated the effects of three antimalarial compounds, quinine (QN), quinidine (QND) and quinacrine (QCR) in a murine schistosomiasis model by using a combination of biochemical, cell biology and molecular biology approaches.
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[Maternal perceptions about the birth of a premature child and care after discharge].
Rev Bras Enferm
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This is a qualitative study, which aimed to identify maternal perceptions on premature birth and care of the newborn during hospitalization and after discharge. The data were collected through semi-structured interviews with 16 mothers of premature infants in NICU or in follow up ambulatory for infants discharged from NICU. The interviews were taped, transcribed and analyzed based on Content Analysis. Results revealed feelings of sadness, anguish, guilt and powerlessness. It was also reveled confidence in the health care team, uncertainty with the care of child at home, the importance of social network support and the role of spirituality for families. Professionals who work with infants should devote more attention to their families, understanding and accepting critical experiments in a humane way.
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Trapezoidal osteochondral autologous plug single-block graft for treating chondral lesions of the knee: clinical and functional medium-term results in an observational study.
Clinics (Sao Paulo)
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To evaluate the clinical and functional results of autologous trapezoidal plug single-block grafts fixed with absorbable chondral darts in patients with osteochondral knee lesions of varying sizes.
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Mitochondrial reactive oxygen species modulate mosquito susceptibility to Plasmodium infection.
PLoS ONE
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Mitochondria perform multiple roles in cell biology, acting as the site of aerobic energy-transducing pathways and as an important source of reactive oxygen species (ROS) that modulate redox metabolism.
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Reconstruction of chronic lesions in the posterolateral corner of the knee with autologous biceps femoralis and fascia lata grafts.
Clinics (Sao Paulo)
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The aim of this study was to evaluate the treatment of patients with chronic lesions in the posterolateral corner of the knee with reconstruction of the fibular collateral ligament, popliteus tendon and popliteofibular ligament and with autografts of the biceps femoris and fascia lata.
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Predicting risk of atrial fibrillation after heart valve surgery: evaluation of a Brazilian risk score.
Rev Bras Cir Cardiovasc
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The aim of this study is to evaluate the applicability of a Brazilian score for predicting atrial fibrillation (AF) in patients undergoing heart valve surgery in the Division of Cardiovascular Surgery of Pronto Socorro Cardiológico de Pernambuco - PROCAPE (Recife, PE, Brazil).
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GuaragnaSCORE satisfactorily predicts outcomes in heart valve surgery in a Brazilian hospital.
Rev Bras Cir Cardiovasc
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The aim of this study is to evaluate the applicability of GuaragnaSCORE for predicting mortality in patients undergoing heart valve surgery in the Division of Cardiovascular Surgery of Pronto Socorro Cardiológico de Pernambuco - PROCAPE, Recife, PE, Brazil.
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Energy and redox homeostasis in tumor cells.
Int J Cell Biol
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Cancer cells display abnormal morphology, chromosomes, and metabolism. This review will focus on the metabolism of tumor cells integrating the available data by way of a functional approach. The first part contains a comprehensive introduction to bioenergetics, mitochondria, and the mechanisms of production and degradation of reactive oxygen species. This will be followed by a discussion on the oxidative metabolism of tumor cells including the morphology, biogenesis, and networking of mitochondria. Tumor cells overexpress proteins that favor fission, such as GTPase dynamin-related protein 1 (Drp1). The interplay between proapoptotic members of the Bcl-2 family that promotes Drp 1-dependent mitochondrial fragmentation and fusogenic antiapoptotic proteins such as Opa-1 will be presented. It will be argued that contrary to the widespread belief that in cancer cells, aerobic glycolysis completely replaces oxidative metabolism, a misrepresentation of Warburgs original results, mitochondria of tumor cells are fully viable and functional. Cancer cells also carry out oxidative metabolism and generally conform to the orthodox model of ATP production maintaining as well an intact electron transport system. Finally, data will be presented indicating that the key to tumor cell survival in an ROS rich environment depends on the overexpression of antioxidant enzymes and high levels of the nonenzymatic antioxidant scavengers.
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In developing our video relationships, we compare around 5 million PubMed articles to our library of over 4,500 methods videos. In some cases the language used in the PubMed abstracts makes matching that content to a JoVE video difficult. In other cases, there happens not to be any content in our video library that is relevant to the topic of a given abstract. In these cases, our algorithms are trying their best to display videos with relevant content, which can sometimes result in matched videos with only a slight relation.