999 resultados para MURINE BETA-THALASSEMIA
Resumo:
In the present study, we investigate whether mast cells and macrophages are involved in the control of IL-1 beta-induced neutrophil migration, as well as the participation of chemotactic mediators. IL-1 beta induced a dose-dependent neutrophil migration to the peritoneal cavity of rats which depends on LTB4, PAF and cytokines, since the animal treatment with inhibitors of these mediators (MK 886, PCA 4248 and dexamethasone respectively) inhibited IL-1 beta-induced neutrophil migration. The neutrophil migration induced by IL-1 beta is dependent on mast cells and macrophages, since depletion of mast cells reduced the process whereas the increase of macrophage population enhanced the migration. Moreover, mast cells or macrophages stimulated with IL-1 beta released a neutrophil chemotactic factor, which mimicked the neutrophil migration induced by IL-1 beta. The chemotactic activity of the supernatant of IL-1 beta-stimulated macrophages is due to the presence of LTB4, since MK 886 inhibited its release. Moreover, the chemotactic activity of IL-1 beta-stimulated mast cells supernatant is due to the presence of IL-1 beta and TNF-alpha, since antibodies against these cytokines inhibited its activity. Furthermore, significant amounts of these cytokines were detected in the supernatant. In conclusion, our results suggest that neutrophil migration induced by IL-1 beta depends upon LTB4 released by macrophages and upon IL-1 beta and TNF alpha released by mast cells.
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IL-13 and eotaxin play important, inter-related roles in asthma models. In the lungs, CysLT, produced by the 5-LO-LTC4S pathway, mediate some local responses to IL-13 and eotaxin; in bone marrow, CysLT enhance IL-5-dependent eosinophil differentiation. We examined the effects of IL-13 and eotaxin on eosinophil differentiation. Semi-solid or liquid cultures were established from murine bone marrow with GM-CSF or IL-5, respectively, and the effects of IL-13, eotaxin, or CysLT on eosinophil colony formation and on eosinophil differentiation in liquid culture were evaluated, in the absence or presence of: a) the 5-LO inhibitor zileuton, the FLAP inhibitor MK886, or the CysLT1R antagonists, montelukast and MK571; b) mutations that inactivate 5-LO, LTC4S, or CysLT1R; and c) neutralizing mAb against eotaxin and its CCR3 receptor. Both cytokines enhanced GM-CSF-dependent eosinophil colony formation and IL-5-stimulated eosinophil differentiation. Although IL-13 did not induce eotaxin production, its effects were abolished by anti-eotaxin and anti-CCR3 antibodies, suggesting up-regulation by IL-13 of responses to endogenous eotaxin. Anti-CCR3 blocked eotaxin completely. The effects of both cytokines were prevented by zileuton, MK886, montelukast, and MK571, as well as by inactivation of the genes coding for 5-LO, LTC4S, and CysLT1R. In the absence of either cytokine, these treatments or mutations had no effect. These findings provide evidence for: a) a novel role of eotaxin and IL-13 in regulating eosinophilopoiesis; and b) a role for CysLTRs in bone marrow cells in transducing cytokine regulatory signals. J. Leukoc. Biol. 87: 885-893; 2010.
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IgA nephropathy (IgAN) is a kidney disease with a varying renal prognosis. Recently, many studies have demonstrated that renal alpha-smooth muscle actin (alpha-SMA) and transforming growth factor (TGF-beta 1) expression, as well interstitial mast cell infiltrates could represent a prognostic marker in several renal diseases. The aim of our study was to analyze the prognostic value of mast cell, TGF-beta 1 and alpha-SMA expression in IgAN. A survey of the medical records and renal biopsy reports of 62 patients with a diagnosis of IgAN followed-up from 1987 to 2003 was performed. The mean follow-up time was 74.7 +/- 50.0 months. The immunohistochemical studies were performed using a monoclonal antibody anti-human mast cell tryptase, a polyclonal antibody anti-human TGF-beta 1, and a monoclonal antibody anti-human alpha-SMA. An unfavorable clinical course of IgAN was related to interstitial mast cell infiltrates and alpha-SMA expression in the tubulointerstitial area. Expression of glomerular TGF-beta 1 and alpha-SMA, and interstitial TGF-beta 1 is not correlated with clinical course in IgAN. In conclusion, the increased number of mast cells and higher alpha-SMA expression in the tubulointerstitial area may be predictive factors for the poor prognosis of patients with IgAN.
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The chronic mild stress (CMS) model has been used as an animal model of depression which induces anhedonic behavior in rodents. The present study was aimed to evaluate the behavioral and physiological effects of administration of P-carboline harmine in rats exposed to CMS Procedure. To this aim, after 40 days of exposure to CMS procedure, rats were treated with harmine (15 mg/kg/day) for 7 days. In this study, sweet food consumption, adrenal gland weight, adrenocorticotrophin hormone (ACTH) levels, and hippocampal brain-derived-neurotrophic factor (BDNF) protein levels were assessed. Our findings demonstrated that chronic stressful situations induced anhedonia, hypertrophy of adrenal gland weight, increase ACTH circulating levels in rats and increase BDNF protein levels. Interestingly, treatment with harmine reversed anhedonia, the increase of adrenal gland weight, normalized ACTH circulating levels and BDNF protein levels. Finally, these findings further support the hypothesis that harmine could be a new pharmacological tool for the treatment of depression. (C) 2009 Elsevier Inc. All rights reserved.
Resumo:
Background Porphyria cutanea tarda (PCT) is a metabolic disease characterized by vesicles and blisters in sun-exposed areas and scleroderma-like lesions in sun-exposed and non-sun-exposed areas. Mast cells participate in the pathogenesis of bullous diseases and diseases that show sclerosis, including PCT. Moreover, transforming growth factor-beta (TGF-beta) is the main cytokine in the development of tissue sclerosis. The correlation of mast cells and TGF-beta with the lesions of PCT has not been examined, however. The possible role of mast cells and TGF-beta (and the relationship between them) in the development of PCT lesions is discussed. Methods To quantify mast cells and cells expressing TGF-beta in skin samples from patients with PCT and controls, immunohistochemical studies were performed in tissue sections allied to morphometric analyses. Results The numbers of mast cells and cells expressing TGF-beta per square millimiter were increased in the PCT group relative to controls, and there was a direct and significant correlation between the mast cell number and cells expressing TGF-beta in PCT. Conclusions The results suggest that the increased number of mast cells and of cells expressing TGF-beta, as well as their direct correlation, may contribute to the pathogenesis of the skin lesions in PCT.
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Topoisomerases are ubiquitous nuclear enzymes that regulate DNA structure in eukaryotic cells. The role of topoisomerase III beta, the newest member of the topoisomerase family, in the clinical outcome of breast cancer is still poorly understood. This study aims to investigate the immunoexpression of topoisomerase III beta in breast cancer and its relationships with clinicopathologic features and immunohistochemical markers of prognostic significance in breast pathology. Using tissue microarrays containing 171 cases of primary invasive breast cancer, we analyzed the immunoexpression of topoisomerase III beta, estrogen receptor, progesterone receptor, HER-2, BRCA-1, p53, and Ki67. Immunostaining for topoisomerase III beta was found in 33.9% of breast carcinomas, and immunopositivity was correlated with distant metastasis (P = .036) and death (P = .006). Decreased expression of topoisomerase III beta correlated with low expression of Ki67 (P < .001) and negativity for HER-2 (P < .001), BRCA-1 (P = .001), and p53 (P < .001). In the multivariate analysis, topoisomerase Hip expression was a significant predictor of survival (hazard ratio, 3.006 [95% confidence interval, 1.582-5.715]; P = .001). In conclusion, topoisomerase III beta expression can be a useful marker in assessing the prognosis of patients with breast cancer and is an independent predictor of survival. (C) 2010 Elsevier Inc. All rights reserved.
beta 1 Integrin and VEGF expression in an experimental model of brain tissue heterotopia in the lung
Resumo:
Integrins and vascular endothelial growth factor (VEGF) are crucially involved in interaction, proliferation, migration, and survival of the cells. However, there is no report in the literature about beta 1 integrin and VEGF expression in heterotopic brain tissue. The aim of this study was to assess beta 1 integrin and VEGF expression in experimental brain tissue heterotopia in the lung during both fetal and neonatal periods. Twenty-four pregnant female Swiss mice were used to induce brain tissue heterotopia on the 15th gestational day. Briefly, the brain of one fetus of each dam was extracted, disaggregated, and injected into the right hemithorax of siblings. Six of these fetuses with pulmonary brain tissue implantation were collected on the 18th gestational day (group E18) and six other on the eighth postnatal day (group P8). Immunohistochemistry of the fetal trunks showed implantation of glial fibrillary acidic protein- and neuronal nuclei-positive heterotopic brain tissue, which were also positive for beta 1 integrin and VEGF in both groups E18 and P8. These results indicate that brain tissue heterotopia during fetal and postnatal period is able to complete integration with the lung tissue as well as to induce vascular proliferation which are the necessary steps for a successful implantation.
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Evidence from our laboratory has shown alterations in myocardial structure in severe sepsis/septic shock. The morphological alterations are heralded by sarcolemmal damage, characterized by increased plasma membrane permeability caused by oxidative damage to lipids and proteins. The critical importance of the dystrophin-glycoprotein complex (DGC) in maintaining sarcolemmal stability led us to hypothesize that loss of dystrophin and associated glycoproteins could be involved in early increased sarcolemmal permeability in experimentally induced septic cardiomyopathy. Male C57Bl/6 mice were subjected to sham operation and moderate (MSI) or severe (SSI) septic injury induced by cecal ligation and puncture (CLP). Using western blot and immunofluorescence, a downregulation of dystrophin and beta-dystroglycan expression in both severe and moderate injury could be observed in septic hearts. The immunofluorescent and protein amount expressions of laminin-alpha 2 were similar in SSI and sham-operated hearts. Consonantly, the evaluation of plasma membrane permeability by intracellular albumin staining provided evidence of severe injury of the sarcolemma in SSI hearts, whereas antioxidant treatment significantly attenuated the loss of sarcolemmal dystrophin expression and the increased membrane permeability. This study offers novel and mechanistic data to clarify subcellular events in the pathogenesis of cardiac dysfunction in severe sepsis. The main finding was that severe sepsis leads to a marked reduction in membrane localization of dystrophin and beta-dystroglycan in septic cardiomyocytes, a process that may constitute a structural basis of sepsis-induced cardiac depression. In addition, increased sarcolemmal permeability suggests functional impairment of the DGC complex in cardiac myofibers. In vivo observation that antioxidant treatment significantly abrogated the loss of dystrophin expression and plasma membrane increased permeability supports the hypothesis that oxidative damage may mediate the loss of dystrophin and beta-dystroglycan in septic mice. These abnormal parameters emerge as therapeutic targets and their modulation may provide beneficial effects on future cardiovascular outcomes and mortality in sepsis. Laboratory Investigation (2010) 90, 531-542; doi: 10.1038/labinvest.2010.3; published online 8 February 2010
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An effective innate immune recognition of the intracellular protozoan parasite Trypanosoma cruzi is critical for host resistance against Chagas disease, a severe and chronic illness that affects millions of people in Latin America. In this study, we evaluated the participation of nucleotide-binding oligomerization domain (Nod)like receptor proteins in host response to T cruzi infection and found that Nod1-dependent, but not Nod2-dependent, responses are required for host resistance against infection. Bone marrow-derived macrophages from Nod1(-/-) mice showed an impaired induction of NF-kappa B-dependent products in response to infection and failed to restrict T cruzi infection in presence of IFN-gamma. Despite normal cytokine production in the sera, Nod1(-/-) mice were highly susceptible to T cruzi infection, in a similar manner to MyD88(-/-) and NO synthase 2(-/-) mice. These studies indicate that Nod1-dependent responses account for host resistance against T cruzi infection by mechanisms independent of cytokine production. The Journal of Immunology, 2010, 184: 1148-1152.
Resumo:
Our objective was to describe the prevalence of low concentrations of retinol, beta-carotene, and vitamin E in a group of human immunodeficiency virus (HIV)-infected Latin American children and a comparison group of HIV-exposed, uninfected children. Our hypothesis was that the rates of low concentrations of these micronutrients would be higher in the HIV-infected group than those in the HIV-exposed, uninfected group. This was a cross-sectional substudy of a larger cohort study at clinical pediatric HIV centers in Latin America. Serum levels of micronutrients were measured in the first stored sample obtained after each child`s first birthday by high-performance liquid chromatography. Low concentrations of retinol, beta-carotene, and vitamin E were defined as serum levels below 0.70, 0.35, and 18.0 mu mol/L, respectively. The Population for this analysis was 336 children (124 HIV-infected, 212 HIV-exposed, uninfected) aged I year or older to younger than 4 years. Rates of low concentrations were 74% for retinol, 27% for beta-carotene, and 89% for vitamin E. These rates were not affected by HIV status. Among the HIV-infected children, those treated with anti retrovirals were less likely to have retinol deficiency, but no other HIV-related factors correlated with micronutrient low serum levels. Low concentrations of retinol, beta-carotene, and vitamin E are very common in children exposed to HIV living in Brazil, Argentina, and Mexico, regardless of HIV-infection status. Published by Elsevier Inc.
Resumo:
Twenty-five extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli clinical isolates from Rio de Janeiro, Brazil were characterized by isoelectric focusing, PCR and sequencing of bla(ESBL) genes, plasmid-mediated quinolone resistance determinants, phylogenetic groups, replicon typing, pulsed-field electrophoresis, and multilocus sequencing typing. Twenty-three (92%) ESBL-producing E. coli isolates were positive for bla(CTX-M) genes, aac(6`)-lb-cr, and qnrB. Genetic relatedness of ESBL producers clustered seven (28%) CTX-M-15-producing isolates as sequence type (ST) 410, clonal complex (CC) 23, and two (8%) as clone O25-ST131. Our results illustrate the predominance of phylo-group A (52%), ST410 (CC 23) and CTX-M-15 among ESBL-producing E. coli isolates from hospitals in Rio de Janeiro.
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Objective. The objective of this study was to investigate the mediators and the resident peritoneal cells involved in the neutrophil migration (NM) induced by mineral trioxide aggregate (MTA) in mice. Study design. MTA (25 mg/cavity) was injected into normal and pretreated peritoneal cavities (PC) with indomethacin (IND), dexamethasone (DEX), BWA4C, U75302, antimacrophage inflammatory protein-2 (MIP-2), and anti-interleukin-1 beta (IL-1 beta) antibodies and the NM was determined. The role of macrophage (MO) and mast cells (MAST) was determined by administration of thioglycollate 3% or 48/80 compound, respectively. The concentration of IL-1 beta and MIP-2 exudates was measured by ELISA. Results. MTA induced dose-and time-dependent NM into mice PC, with the participation of MO and MAST. NM was inhibited by DEX, BWA4C, and U75302, as well as anti-MIP-2 and anti-IL-1 beta antibodies. In the exudates, IL-1 beta and MIP-2 were detected. Conclusions. This study suggests that MTA induces NM via a mechanism dependent on MAST and MO mediated by IL-1 beta, MIP-2, and LTB(4).
Resumo:
The objective was to evaluate the effect of beta-lactoglobulin (beta-lg) polymorphism and seasonality on milk composition (fat, lactose, total solids, milk urea nitrogen, total protein, true protein, casein and somatic cell counts) of Holstein and Girolando cows. Milk and blood samples from 278 Holsteins cows and 156 Girolando cows were taken during two dry seasons and two rainy seasons, for milk composition analysis and to determine beta-lg genotypes, respectively. BB genotype was the most frequent for both breeds, followed by AA genotype for Holstein (BB>AA>AB) and by AB for Girolando cows (BB>AB>AA). No differences were found in milk compositional characteristics among genetic variants of beta-lg (AA, AB and BB) either between Holstein or Girolando cows. No association between milk composition and beta-lg genetic polymorphism was observed. During the dry season, independently of the breed considered, higher contents of lactose, true protein, casein and casein :true protein ratio were found.
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Pfaffia paniculata (Brazilian ginseng) roots and/or its extracts have shown anti-neoplastic, chemopreventive, and anti-angiogenic properties. The aim of this work was to investigate the chemopreventive mechanisms of this root in Mice Submitted to the infant model of hepatocarcinogenesis, evaluating the effects oil cellular proliferation, apoptosis. and intercellular communication. Fifteen-day-old BALB/c male mice were given, i.p., 10 mu g/g of the carcinogen N-nitrosodiethylamine (DEN). Animals were separated into three groups at weaning and were given different concentrations of powdered P. paniculata root (0%, 2%, or 10%) added to commercial food for 27 weeks. Control group (CT) was not exposed to the carcinogen and was given ration without the root. After euthanasia, the animals` liver and body weight were measured. Liver fragments were sampled to Study intercellular communication, molecular biology, and histopathological analysis. Cellular proliferation was evaluated by immunohistochemistry for PCNA, apoptosis was evaluated by apoptotic bodies count and alkaline cornet technique, and inter-cellular communication by diffusion of lucifer yellow dye, immunofluorescence, western blot and real-time PCR for connexins 26 and 32. Chronic treatment with powdered P. paniculata root reduced cellular proliferation and increased apoptosis in the 2%, group. Animals in the 10% group had an increase in apoptosis with chronic inflammatory process. Intercellular communication showed no alterations in any of the groups analyzed. These results Indicate that chemopreventive effects of P. paniculata are related to the control of cellular proliferation and apoptosis, but not to cell communication and/or connexin expression, and are directly Influenced by the root concentration. (C) 2009 Elsevier GmbH. All rights reserved.
Resumo:
During the process of maturation in the oviduct, canine oocytes in the germinal vesicle stage are exposed to decreasing levels of estradiol-17 beta and increasing levels of progesterone. However, hormone concentrations in the microenvironments in which they act are higher than serum concentrations. Therefore, the aim of the present study was to compare the meiotic competence of canine oocytes harvested from anestrous bitches in culture medium containing high concentrations (20 mu g ml(-1)) of estradiol-17 beta and/or progesterone in association to gonadotropins (luteinizing hormone and follicle-stimulating hormone) using three different maturation periods (48, 72, and 96 h). Oocytes were cultured in tissue culture medium (TCM-199) and arranged in four experimental groups: group control, group E2 (estradiol-17 beta), group P4 (progesterone), and group E2 + P4. Regardless of the maturation period, groups P4 and E2 + P4 presented statistically higher rate of germinal vesicle breakdown oocytes compared to the group control and group E2. There were no significant differences among groups on germinal vesicle, metaphase I, metaphase II, and degenerated or unidentifiable oocytes rates. The mean percentage of metaphase II oocytes was higher at 96 h when compared to 72 h. Results of the present research indicate no influence of estradiol-17 beta supplementation, unless in association with progesterone. There is an evidence of the positive effect of progesterone on germinal vesicle breakdown. Results also showed that extended periods of in vitro maturation affect positively maturation rates to metaphase II of low competent oocytes harvested from anestrous bitches, independent of the maturation media. In conclusion, high concentrations of steroids, especially progesterone, have positive effect on in vitro oocyte maturation when the oocytes are derived from the anestrous status.