338 resultados para post vaccinal response


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The aim of this Study was to determine if protein-energy malnutrition Could affect the hematologic response to granulocyte colony-stimulating factor (G-CSF). Swiss mice were fled a low-protein diet containing 4% protein, whereas control mice were fed a 20% protein-containing diet. After the malnourished group lost 20% of their original body weight, the mice were subdivided in 2 treatment groups, and hematopoietic parameters were studied. Mice were injected with either 8 mu g/kg per day of G-CSF or saline twice daily for 4 days. Malnourished mice developed anemia with reticulopenia and leukopenia with depletion of granulocytes and lymphocytes. Both malnourished and control mice treated with G-CSF showed a significant increase in neutrophils; however, in the control group, this increase was more pronounced compared to the malnourished group (4.5-fold and 3.4-fold, respectively). Granulocyte colony-stimulating factor administration increased bone marrow blastic (P < .001) and granulocytic (P < .01) compartments in the controls bill had no significant effect oil these hematopoietic compartments in the Malnourished animals (P = .08 and P = .62, respectively). We report that malnourished mice display an impaired response to G-CSF, which contributes to the decreased production of leukocytes in protein-energy malnutrition. (C) 2008 Elsevier Inc. All rights reserved.

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Malnutrition modifies resistance to infection by impairing a number of physiological processes including hematopoesis and the immune response. In this study, we examined the production of Interleukin-4 (IL-4) and IL-10 in response to lipopolysaccharide (LPS) and also evaluated the cellularity of the blood, bone marrow, and spleen in a mouse model of protein-energy malnutrition. Two-month-old male Swiss mice were subjected to protein-energy malnutrition (PEM) with a low-protein diet (4%) as compared to the control diet (20%). When the experimental group lost approximately 20% of their original body weight, the animals from both groups received 1.25 mu g of LPS intravenously. The Cells ill the blood, bone marrow, and spleen were counted, and circulating levels of IL-4 and IL-10 were evaluated in animals stimulated with LPS. Cells from the spleen, bone marrow, and peritoneal cavity of non-inoculated animals were collected for Culture to evaluate the production of IL-4 and IL-10 after stimulating these cells with 1.25 mu g of LPS in vitro. Malnourished animals presented leucopenia and a severe reduction in bone marrow, spleen, and peritoneal cavity cellularity before and after Stimulus with LPS. The circulating levels of IL-10 were increased in malnourished animals inoculated with LPS when compared to control animals, although the levels of IL-4 did not differ. In cells cultured with LPS, we observed high levels of IL-10 in the bone marrow cells of malnourished animals. These findings suggest that malnourished mice present a deficient immune response to LPS. These alterations may be partly responsible for the immunodeficiency observed in these malnourished mice.

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Background: The transcription factors SREBP1 and SCAP are involved in intracellular cholesterol homeostasis. Polymorphisms of these genes have been associated with variations on serum lipid levels and response to statins that are potent cholesterol-lowering drugs. We evaluated the effects of atorvastatin on SREBF1a and SCAP mRNA expression in peripheral blood mononuclear cells (PBMC) and a possible association with gene polymorphisms and lowering-cholesterol response. Methods: Fifty-nine hypercholesterolemic patients were treated with atorvastatin (10 mg/day for 4 weeks). Serum lipid profile and mRNA expression in PBMC were assessed before and after the treatment. Gene expression was quantified by real-time PCR using GAPD as endogenous reference and mRNA expression in HepG2 cells as calibrator. SREBF1 -36delG and SCAP A2386G polymorphisms were detected by PCR-RFLP. Results: Our results showed that transcription of SREBF1a and SCAP was coordinately regulated by atorvastatin (r=0.595, p<0.001), and that reduction in SCAP transcription was associated with the 2386AA genotype (p=0.019). Individuals who responded to atorvastatin with a downregulation of SCAP had also a lower triglyceride compared to those who responded to atorvastatin with an upregulation of SCAP. Conclusion: Atorvastatin has differential effects on SREBF1a and SCAP mRNA expression in PBMC that are associated with baseline transcription levels, triglycerides response to atorvastatin and SCAP A2386G polymorphism. (c) 2008 Elsevier B.V. All rights reserved.

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Inulin was used as a prebiotic to improve the quality and consistency of skim milk fermented by co-cultures and pure Cultures of Lactobacillus acidophilus, Lactobacillus rhamnosus, Lactobacillus bulgaricus and Bifidobacterium lactis with Streptococcus thermophilus. We compared, either in the presence or absence of 4 g inulin/100 g, the results of the main kinetic parameters, specifically the generation time (t(g)), the maximum acidification rate (V(max)). and the times to reach V(max) (t(max)), to attain pH 5.0 (t(pH5.0)) and to complete the fermentation (t(pH4.5)). Post-acidification, lactic acid formation and cell counts were also determined and compared, either 1 day after the fermentation was complete or after 7 day storage at 4 degrees C. In general, inulin addition to the milk increased in co-cultures V(max), decreased t(max), t(g) and t(pH4.5), favored post-acidification, exerted a bifidogenic effect, and preserved almost intact cell viability during storage. In addition, S. thermophilus was shown to stimulate the metabolism of the other lactic bacteria. Contrary to co-cultures, most of the effects in pure Cultures were not statistically significant. The most important aspect of this paper is the use of the generation time as a toot to investigate the microbial response to inulin addition. (c) 2009 Elsevier Ltd. All rights reserved.

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This work aimed to study the in vitro colonic fermentation profile of unavailable carbohydrates of two different kinds of unripe banana flour and to evaluate their postprandial glycemic responses. The unripe banana mass (UBM), obtained from the cooked pulp of unripe bananas (Musa acuminata, Nanico variety), and the unripe banana starch (UBS), obtained from isolated starch of unripe banana, plantain type (Musa paradisiaca) in natura, were studied. The fermentability of the flours was evaluated by different parameters, using rat inoculum, as well as the glycemic response produced after the ingestion by healthy volunteers. The flours presented high concentration of unavailable carbohydrates, which varied in the content of resistant starch, dietary fiber and indigestible fraction (IF). The in vitro colonic fermentation of the flours was high, 98% for the UBS and 75% for the UBM when expressed by the total amount of SCFA such as acetate, butyrate and propionate in relation to lactulose. The increase in the area under the glycemic curve after ingestion of the flours was 90% lower for the UBS and 40% lower for the UBM than the increase produced after bread intake. These characteristics highlight the potential of UBM and UBS as functional ingredients. However, in vivo studies are necessary in order to evaluate the possible benefic effects of the fermentation on intestinal health.

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Exposure to oxygen may induce a lack of functionality of probiotic dairy foods because the anaerobic metabolism of probiotic bacteria compromises during storage the maintenance of their viability to provide benefits to consumer health. Glucose oxidase can constitute a potential alternative to increase the survival of probiotic bacteria in yogurt because it consumes the oxygen permeating to the inside of the pot during storage, thus making it possible to avoid the use of chemical additives. This research aimed to optimize the processing of probiotic yogurt supplemented with glucose oxidase using response surface methodology and to determine the levels of glucose and glucose oxidase that minimize the concentration of dissolved oxygen and maximize the Bifidobacterium longum count by the desirability function. Response surface methodology mathematical models adequately described the process, with adjusted determination coefficients of 83% for the oxygen and 94% for the B. longum. Linear and quadratic effects of the glucose oxidase were reported for the oxygen model, whereas for the B. longum count model an influence of the glucose oxidase at the linear level was observed followed by the quadratic influence of glucose and quadratic effect of glucose oxidase. The desirability function indicated that 62.32 ppm of glucose oxidase and 4.35 ppm of glucose was the best combination of these components for optimization of probiotic yogurt processing. An additional validation experiment was performed and results showed acceptable error between the predicted and experimental results.

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Despite the increase in the use of natural compounds in place of synthetic derivatives as antioxidants in food products, the extent of this substitution is limited by cost constraints. Thus, the objective of this study was to explore the synergism on the antioxidant activity of natural compounds, for further application in food products. Three hydrosoluble compounds (x(1) = caffeic acid, x(2) = carnosic acid, and x(3) = glutathione) and three liposoluble compounds (x(1) = quercetin, x(2) = rutin, and x(3) = genistein) were mixed according to a ""centroid simplex design"". The antioxidant activity of the mixtures was analyzed by the ferric reducing antioxidant power (FRAP) and oxygen radical absorbance capacity (ORAL) methodologies, and activity was also evaluated in an oxidized mixed micelle prepared with linoleic acid (LAOX). Cubic polynomial models with predictive capacity were obtained when the mixtures were submitted to the LAOX methodology ((y) over cap = 0.56 x(1) + 0.59 x(2) + 0.04 x(3) + 0.41 x(1)x(2) - 0.41 x(1)x(3) - 1.12 x(2)x(3) - 4.01 x(1)x(2)x(3)) for the hydrosoluble compounds, and to FRAP methodology ((y) over cap = 3.26 x(1) + 2.39 x(2) + 0.04 x(3) + 1.51 x(1)x(2) + 1.03 x(1)x(3) + 0.29 x(1)x(3) + 3.20 x(1)x(2)x(3)) for the liposoluble compounds. Optimization of the models suggested that a mixture containing 47% caffeic acid + 53% carnosic acid and a mixture containing 67% quercetin + 33% rutin were potential synergistic combinations for further evaluation using a food matrix.

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The Brazilian Network of Food Data Systems (BRASILFOODS) has been keeping the Brazilian Food Composition Database-USP (TBCA-USP) (http://www.fcf.usp.br/tabela) since 1998. Besides the constant compilation, analysis and update work in the database, the network tries to innovate through the introduction of food information that may contribute to decrease the risk for non-transmissible chronic diseases, such as the profile of carbohydrates and flavonoids in foods. In 2008, data on carbohydrates, individually analyzed, of 112 foods, and 41 data related to the glycemic response produced by foods widely consumed in the country were included in the TBCA-USP. Data (773) about the different flavonoid subclasses of 197 Brazilian foods were compiled and the quality of each data was evaluated according to the USDAs data quality evaluation system. In 2007, BRASILFOODS/USP and INFOODS/FAO organized the 7th International Food Data Conference ""Food Composition and Biodiversity"". This conference was a unique opportunity for interaction between renowned researchers and participants from several countries and it allowed the discussion of aspects that may improve the food composition area. During the period, the LATINFOODS Regional Technical Compilation Committee and BRASILFOODS disseminated to Latin America the Form and Manual for Data Compilation, version 2009, ministered a Food Composition Data Compilation course and developed many activities related to data production and compilation. (C) 2010 Elsevier Inc. All rights reserved.

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Foods that contain unavailable carbohydrates may lower the risks for some non-transmissible chronic diseases because of the potential benefits provided by the products of colonic fermentation. On the other hand, foods that are sources of available carbohydrates may have higher energy value and increase the post-prandial glycemic response. The biomarker glycemic index and the resulting glycemic load may be used to classify foods according to their potential to increase blood glucose. Information about glycemic index and glycemic load may be useful in diet therapy. Currently, food composition tables in Brazil do not provide data for individually analyzed carbohydrates even though some quality data are available in scientific publications. The objectives of this work were to produce and compile information about the concentration of individual carbohydrates in foods and their glycemic responses and to disseminate this information through the Brazilian Food Composition Database (TBCA-USP). The glycemic index and glycemic load of foods were evaluated in healthy individuals. Concentrations of available carbohydrates (soluble sugars and available starch) and unavailable carbohydrates (dietary fiber, resistant starch, beta-glucans, fructans) were quantified by official methods, and other national data were compiled. TBCA-USP (http://www.fcf.usp.br/tabela), which is used by professionals and the population in general, now offers both chemical and biological information for carbohydrates. (C) 2009 Elsevier Inc. All rights reserved.

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Aim of the study: Species of Lychnophora are used in Brazilian folk medicine as analgesic and anti-inflammatory agents. Chlorogenic acid (CGA) and their analogues are important components of polar extracts of these species, as well in several European and Asian medicinal plants. Some of these phenolic compounds display anti-inflammatory effects. In this paper we report the isolation of CGA from Lychnophora salicifolia and its effects on functions involved in neutrophils locomotion. Materials and methods: LC-MS(n) data confirmed the presence of CGA in the plant. Actions of CGA were investigated on neutrophils obtained from peritoneal cavity of Wistar rats (4h after 1% oyster glycogen solution injection; 10 ml), and incubated with vehicle or with 50, 100 or 1000 mu M CGA in presence of lipopolysaccharide from Escherichia coil (LPS, 5 mu g/ml). Nitric oxide (NO; Griess reaction); prostaglandin E(2) (PGE(2)), interleukin-1 beta (IL-1 beta) and tumor necrosis factor-alpha [TNF-alpha; enzyme-linked immunosorbent assay (EIA)]; protein (flow cytometry) and gene (RT-PCR) expression of L-selectin, beta(2)integrin and platelet-endothelial cell adhesion molecule-1 (PECAM-1) were quantified. In vitro neutrophil adhesion to primary culture of microvascular endothelial cell (PMEC) and neutrophil migration in response to formyl-methionil-leucil-phenilalanine (fMLP, 10(-8)M, Boyden chamber) was determined. Results: CGA treatment did not modify the secretion of inflammatory mediators, but inhibited L-selectin cleavage and reduced beta(2) integrin, independently from its mRNA synthesis, and reduced membrane PECAM-1 expression: inhibited neutrophil adhesion and neutrophil migration induced by fMLP. Conclusions: Based on these findings, we highlight the direct inhibitory actions of CGA on adhesive and locomotion properties of neutrophils, which may contribute to its anti-inflammatory effects and help to explain the use of Lychnophora salicifolia as an anti-inflammatory agent. (C) 2011 Elsevier Ireland Ltd. All rights reserved.

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Background and purpose: The contribution of endothelin-1 (ET-1) to vascular hyper-reactivity associated with chronic ethanol intake, a major risk factor in several cardiovascular diseases, remains to be investigated. Experimental approach: The biphasic haemodynamic responses to ET-1 (0.01-0.1 nmol kg(-1), i.v.) or to the selective ET(B) agonist, IRL1620 (0.001-1.0 nmol kg(-1), i.v.), with or without ET(A) or ET(B) antagonists (BQ123 (c(DTrp-Dasp-Pro-Dval-Leu)) at 1 and 2.5 mg kg(-1) and BQ788 (N-cis-2,6-dimethyl-piperidinocarbonyl-L-gamma-methylleucyl1-D-1methoxycarbonyltryptophanyl-D-norleucine) at 0.25 mg kg(-1), respectively) were tested in anaesthetized rats, after 2 weeks` chronic ethanol treatment. Hepatic parameters and ET receptor protein levels were also determined. Key results: The initial hypotensive responses to ET-1 or IRL1620 were unaffected by chronic ethanol intake, whereas the subsequent pressor effects induced by ET-1, but not by IRL1620, were potentiated. BQ123 at 2.5 but not 1 mg kg(-1) reduced the pressor responses to ET-1 in ethanol-treated rats. Conversely, BQ788 (0.25 mg kg(-1)) potentiated ET-1-induced increases in mean arterial blood pressure in control as well as in ethanol-treated rats. Interestingly, in the latter group, increases in heart rate, induced by ET-1 at a dose of 0.025 mg kg(-1) were enhanced following ET(B) receptor blockade. Finally, we observed higher levels of ET(A) receptor in the heart and mesenteric artery and a reduction of ET(B) receptor protein levels in the aorta and kidney from rats chronically treated with ethanol. Conclusions and implications: Increased vascular reactivity to ET-1 and altered protein levels of ET(A) and ET(B) receptors could play a role in the pathogenesis of cardiovascular complications associated with chronic ethanol consumption.

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In addition to adenosine triphosphate (ATP) production, mitochondria have been implicated in the regulation of several physiological responses in plants, such as programmed cell death (PCD) activation. Salicylic acid (SA) and reactive oxygen species (ROS) are essential signaling molecules involved in such physiological responses; however, the mechanisms by which they act remain unknown. In non-photosynthesizing tissues, mitochondria appear to serve as the main source of ROS generation. Evidence suggests that SA and ROS could regulate plant PCD through a synergistic mechanism that involves mitochondria. Herein, we isolate and characterize the mitochondria from non-photosynthesizing cell suspension cultures of Rubus fruticosus. Furthermore, we assess the primary site of ROS generation and the effects of SA on isolated organelles. Mitochondrial Complex III was found to be the major source of ROS generation in this model. In addition, we discovered that SA inhibits the electron transport chain by inactivating the semiquinone radical during the Q cycle. Computational analyses confirmed the experimental data, and a mechanism for this action is proposed.

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The aims of this study were to evaluate whether air pollution during pre-natal and post-natal phases change habituation and short-term discriminative memories and if oxidants are involved in this process. As secondary objectives, it was to evaluate if the change of filtered to nonfiltered environment could protect the cortex of rats against oxidative stress as well as to modify the behavior of these animals. Wistar, male rats were divided into four groups (n = 12/group): pre and post-natal exposure until adulthood to filtered air (FA); pre-natal period to nonfiltered air (NFA-FA); until (21st post-natal day) and post-natal to filtered air until adulthood (PND21); prenatal to filtered air until PND21 and post-natal to nonfiltered air until adulthood (FA-NFA); pre and post-natal to nonfiltered air (NFA). After 150 days of air pollution exposure, animals were tested in the spontaneous object recognition test to evaluate short-term discriminative and habituation memories. Rats were euthanized; blood was collected for metal determination; cortex dissected for oxidative stress evaluation. There was a significant increase in malondialdehyde (MDA) levels in the NFA group when compared to other groups (FA: 1.730 +/- 0.217; NFA-FA: 1.101 +/- 0.217; FA-NFA: 1.014 +/- 0.300; NFA: 5.978 +/- 1.920 nmol MDA/mg total proteins; p = 0.007). NFA group presented a significant decrease in short-term discriminative (FA: 0.603 +/- 0.106; NFA-FA: 0.669 +/- 0.0666; FA-NFA: 0.374 +/- 0.178; NFA: -0.00631 +/- 0.106 sec; p = 0.006) and an improvement in habituation memories when compared to other groups. Therefore, exposure to air pollution during both those periods impairs short-term discriminative memory and cortical oxidative stress may mediate this process.

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Iron deficiency is a common nutritional disorder, affecting about 30% of the world population. Deficits in iron functional compartments have suppressive effects on the immune system. Environmental problems, age, and other nutrient deficiencies are some of the situations which make human studies difficult and warrant the use of animal models. This study aimed to investigate alterations in the immune system by inducing iron deficiency and promoting recuperation in a mouse model. Hemoglobin concentration, hematocrit, liver iron store, and flow cytometry analyses of cell-surface transferrin receptor (CD71) on peripheral blood and spleen CD4+ and CD8+ T lymphocyte were performed in the control (C) and the iron-deficient (ID) groups of animals at the beginning and end of the experiment. Hematological indices of C and ID mice were not different but the iron stores of ID mice were significantly reduced. Although T cell subsets were not altered, the percentage of T cells expressing CD71 was significantly increased by ID. The results suggest that iron deficiency induced by our experimental model would mimic the early events in the onset of anemia, where thymus atrophy is not enough to influence subset composition of T cells, which can still respond to iron deficiency by upregulating the expression of transferrin receptor.

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Zinc is an essential nutritional component required for normal development and maintenance of immune functions. The possible effects of zinc in upregulating the host immune response during the acute and chronic phases of experimental Chagas` disease were evaluated. In young, infected and Zn-supplemented animals, higher concentrations of IFN-gamma and NO were observed. During the chronic phase, decreased concentrations of NO and IFN-gamma were found for older infected animals that received Zn supplementation. For young animals, hearts from Zn-supplemented groups displayed reduced inflammatory infiltrate, heart weight and number of amastigote burdens. For older, infected and Zn-supplemented animals amastigote nests were absent with reduced inflammatory cell infiltrate. This study identifies a potentially novel therapeutic approach that could control the parasite load during acute phase of disease, consequently preventing the deleterious, parasite-elicited responses observed during chronic phase. (C) 2008 Elsevier Inc. All rights reserved.