331 resultados para Factor de necrosis tumoral alfa
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This multicentric population-based study in Brazil is the first national effort to estimate the prevalence of hepatitis B (HBV) and risk factors in the capital cities of the Northeast, Central-West, and Federal Districts (2004-2005). Random multistage cluster sampling was used to select persons 13-69 years of age. Markers for HBV were tested by enzyme-linked immunosorbent assay. The HBV genotypes were determined by sequencing hepatitis B surface antigen (HBsAg). Multivariate analyses and simple catalytic model were performed. Overall, 7,881 persons were included; < 70 per cent were not vaccinated. Positivity for HBsAg was less than 1 per cent among non-vaccinated persons and genotypes A, D, and F co-circulated. The incidence of infection increased with age with similar force of infection in all regions. Males and persons having initiated sexual activity were associated with HBV infection in the two settings; healthcare jobs and prior hospitalization were risk factors in the Federal District. Our survey classified these regions as areas with HBV endemicity and highlighted the risk factors differences among the settings
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A desnutrição proteico-energética modifica a resistência à infecção, modificando diversos processos fisiológicos, incluindo a hematopoiese e as funções imunológicas. Neste estudo, avaliamos as concentrações séricas do fator C3 e do Sistema Complemento total (CH50) em um modelo no qual camundongos submetidos à desnutrição proteico-energética são estimulados com lipopolissacarídeo (LPS), e avaliamos a celularidade periférica, medular e esplênica. Camundongos Swiss, machos, adultos, com dois meses de idade foram submetidos ao processo de desnutrição proteica com uma dieta contendo 4% de proteína em comparação aos animais controles com uma dieta contendo 20% de proteína. Quando os animais do grupo desnutrido alcançaram aproximadamente 20% de perda de peso, em relação ao inicial, foram inoculados endovenosamente com LPS. As células do sangue, da medula óssea e do baço foram quantificadas, bem como as concentrações circulantes de C3 e CH50 em animais estimulados com LPS. Os animais desnutridos apresentaram anemia e leucopenia, além de redução significativa da celularidade da medula óssea e do baço. Os animais desnutridos apresentaram menor taxa de sobrevivência, bem como das concentrações do fator C3 do complemento e do complemento total em relação aos animais controles. Estes resultados sugerem que animais desnutridos apresentam uma resposta deficiente aos LPS. A síntese menor do complemento pode ser em parte responsável pela imunodeficiência observada. Estes resultados conduzem-nos a inferir que a desnutrição proteico-energética interfere na ativação da resposta imune
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Background and Aims: Schistosomiasis is an intravascular parasitic disease associated with inflammation. Endothelial cells control leukocyte transmigration and vascular permeability being modulated by pro-inflammatory mediators. Recent data have shown that endothelial cells primed in vivo in the course of a disease keep the information in culture. Herein, we evaluated the impact of schistosomiasis on endothelial cell-regulated events in vivo and in vitro. Methodology and Principal Findings: The experimental groups consisted of Schistosoma mansoni-infected and age-matched control mice. In vivo infection caused a marked influx of leukocytes and an increased protein leakage in the peritoneal cavity, characterizing an inflamed vascular and cellular profile. In vitro leukocyte-mesenteric endothelial cell adhesion was higher in cultured cells from infected mice as compared to controls, either in the basal condition or after treatment with the pro-inflammatory cytokine tumor necrosis factor (TNF). Nitric oxide (NO) donation reduced leukocyte adhesion to endothelial cells from control and infected groups; however, in the later group the effect was more pronounced, probably due to a reduced NO production. Inhibition of control endothelial NO synthase (eNOS) increased leukocyte adhesion to a level similar to the one observed in the infected group. Besides, the adhesion of control leukocytes to endothelial cells from infected animals is similar to the result of infected animals, confirming that schistosomiasis alters endothelial cells function. Furthermore, NO production as well as the expression of eNOS were reduced in cultured endothelial cells from infected animals. On the other hand, the expression of its repressor protein, namely caveolin-1, was similar in both control and infected groups. Conclusion/Significance: Schistosomiasis increases vascular permeability and endothelial cell-leukocyte interaction in vivo and in vitro. These effects are partially explained by a reduced eNOS expression. In addition, our data show that the disease primes endothelial cells in vivo, which keep the acquired phenotype in culture.
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Objective: To evaluate the effects of local administration of epidermal growth factor (EGF) located within liposomes on recruitment of osteoclasts during mechanical force in rats. Materials and Methods: An orthodontic elastic band was inserted between the left upper first and second molars, to move mesially the first molar. Rats were randomly divided into 4 groups (n = 8): EGF (2 ng/mu L) located within liposomes (group 1), liposomes only (group 2), soluble EGF (2 ng/mu L; group 3), or vehicle alone (group 4). The solutions were injected into the region of the root furcation of the left first molar after elastic band insertion. Tooth movement was measured using a plaster model of the maxilla, and the number of osteoclasts recruited at the pressure side of the first molar was histologically evaluated. Results: Intergroup analysis showed that there was no significant difference between group 2 and group 4 (P >.05) and between group 1 and group 3 (P >.05). However, group 1 and group 3 exhibited greater differences in tooth movement than group 2 and group 4 (P <.05). On the other hand, group 1 showed greater tooth movement than groups 2 and 4 with statistical significance (P <.01). The increase in the number of osteoclasts in group 1 was significantly higher than in the other groups (P <.05). Conclusion: Exogenous EGF-liposome administration has an additive effect when compared with soluble EGF on the rate of osteoclast recruitment, producing faster bone resorption and tooth movement.
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Objectives. To evaluate lipid profile changes after anti-TNF therapy in patients with psoriatic arthritis (PsA). Methods. Fifteen PsA patients (eight polyarticular, four oligoarticular, two axial, and one mutilating) under infliximab were included. None had dyslipoproteinemia or previous statin use. Total cholesterol (TC) and its fractions, inflammatory markers, and prednisone use were evaluated. Results. The comparisons of lipid levels between baseline and after three months (3M) of anti-TNF therapy showed that there was a significant increase in mean triglycerides (117.8 +/- 49.7 versus 140.1 +/- 64.1 mg/dL, P = 0.028) and VLDL-c (23.6 +/- 10.5 versus 28.4 +/- 13.7 mg/dL, P = 0.019) levels. In contrast, there were no differences in the mean TC (P = 0.28), LDL-c (P = 0.42), and HDL-c (P = 0.26) levels. Analysis of the frequencies of each lipid alteration at baseline and at 3M were alike (P > 0.05). Positive correlations were found between VLDL-c and CRP (r = 0.647, P = 0.009) and between triglycerides and CRP (r = 0.604, P = 0.017) levels at 3M. ESR reduction was observed after 3M (P = 0.04). Mean prednisone dose remained stable at beginning and at 3M (P = 0.37). Conclusion. This study demonstrated that anti-TNF may increase TG and VLDL-c levels in PsA patients after three months.
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Background: Cardiac remodeling is generally an adverse sign and is associated with heart failure (HF) progression. NFkB, an important transcription factor involved in many cell survival pathways, has been implicated in the remodeling process, but its role in the heart is still controversial. Recently, a promoter polymorphism associated with a lesser activation of the NFKB1 gene was also associated with Dilated Cardiomyopathy. The purpose of this study was to evaluate the association of this polymorphism with clinical and functional characteristics of heart failure patients of different etiologies. Methods: A total of 493 patients with HF and 916 individuals from a cohort of individuals from the general population were investigated. The NFKB1-94 insertion/deletion ATTG polymorphism was genotyped by High Resolution Melt discrimination. Allele and genotype frequencies were compared between groups. In addition, frequencies or mean values of different phenotypes associated with cardiovascular disease were compared between genotype groups. Finally, patients were prospectively followed-up for death incidence and genotypes for the polymorphism were compared regarding disease onset and mortality incidence in HF patients. Results: We did not find differences in genotype and allelic frequencies between cases and controls. Interestingly, we found an association between the ATTG(1)/ATTG(1) genotype with right ventricle diameter (P = 0.001), left ventricle diastolic diameter (P = 0.04), and ejection fraction (EF) (P = 0.016), being the genotype ATTG(1)/ATTG(1) more frequent in patients with EF lower than 50% (P = 0.01). Finally, we observed a significantly earlier disease onset in ATTG(1)/ATTG(1) carriers. Conclusion: There is no genotype or allelic association between the studied polymorphism and the occurrence of HF in the tested population. However, our data suggest that a diminished activation of NFKB1, previously associated with the ATTG(1)/ATTG(1) genotype, may act modulating on the onset of disease and, once the individual has HF, the genotype may modulate disease severity by increasing cardiac remodeling and function deterioration.
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Background: Claudin-4 (CLDN4) is one of several proteins that act as molecular mediators of embryo implantation. Recently, we examined immunolabeling of leukemia inhibitory factor (LIF) in the endometrial tissue of 52 IVF patients, and found that LIF staining intensity was strongly correlated with successful pregnancy initiation. In the same set of patients, we have now examined endometrial CLDN4 expression, to see how expression intensity may vary with LIF. We examined CLDN4 in the luteal phase of the menstrual cycle, immediately preceding IVF treatment. Our aim was to compare expression of LIF and CLDN4 in the luteal phase, and document these patterns as putative biomarkers for pregnancy. Methods: Endometrial tissue was collected from women undergoing IVF. Endometrial biopsies were obtained during the luteal phase preceding IVF, and were then used for tissue microarray (TMA) immunolabeling of CLDN4. Previously published LIF expression data were then combined with CLDN4 expression data, to determine CLDN4/LIF expression patterns. Associations between successful pregnancy after IVF and combined CLDN4/LIF expression patterns were evaluated. Results: Four patterns of immunolabeling were observed in the endometrial samples: 16% showed weak CLDN4 and strong LIF (CLDN4(-)/LIF(+)); 20% showed strong CLDN4 and strong LIF (LIF(+)/CLDN4(+)); 28% showed strong CLDN4 and weak LIF (CLDN4(+)/LIF(-)); and 36% showed weak CLDN4 and weak LIF (CLDN4(-)/LIF(-)). Successful implantation after IVF was associated with CLDN4(-)/LIF(+)(p = 0.003). Patients showing this endometrial CLDN4(-)/LIF(+) immunolabeling were also 6 times more likely to achieve pregnancy than patients with endometrial CLDN4(+)/LIF(-) immunolabeling (p = 0.007). Conclusion: The combined immunolabeling expression of CLDN4(-)/LIF(+) in endometrial tissue is a potential biomarker for predicting successful pregnancy in IVF candidates.
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Background: The vascular endothelial growth factor (VEGF) is a major promoter of endothelial growth and migration. Some studies have shown a correlation between expression of this growth factor and prognosis in several cancers, including well-differentiated thyroid cancer. Aim: We studied VEGF expression, local invasiveness, and other prognostic factors in papillary thyroid carcinoma (PTC) to test the hypothesis that the expression of VEGF is correlated with the degree of invasion of PTC. Patients and Methods: Clinical and pathological data of 76 patients with PTC were retrospectively reviewed. Group 1 consisted of patients with gross locally invasive tumors, group 2 consisted of patients with only invasion of the thyroid capsule, and group 3 consisted of patients with noninvasive PTC. Results: VEGF expression was noted within the tumor in all groups of PTC patients but was absent in the surrounding normal tissue. Older patients had higher expression of VEGF than younger patients. The age of patients with strong reaction to VEGF was 46 +/- 14 (mean +/- standard deviation), and that in patients with a weaker reaction was 39 +/- 16 (p<0.05). Only 20% of patients with a follicular variant of PTC had a strong reaction to VEGF compared with 68% of patients with classical PTC (p<0.01). Conclusions: VEGF expression appears to be an early event in the development of PTC. Whether VEGF expression promotes the progression of PTC is not known, but the answer to this question may be important in view of its greater expression in older patients, a group whose prognosis in PTC is worse.
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It has been demonstrated that human adipose tissue-derived mesenchymal stem cells (hASCs) enhance vascular density in ischemic tissues, suggesting that they can differentiate into vascular cells or release angiogenic factors that may stimulate neoangiogenesis. Moreover, there is evidence that shear stress (SS) may activate proliferation and differentiation of embryonic and endothelial precursor stem cells into endothelial cells (ECs). In this work, we investigated the effect of laminar SS in promoting differentiation of hASCs into ECs. SS (10 dyn/cm(2) up to 96 h), produced by a cone plate system, failed to induce EC markers (CD31, vWF, Flk-1) on hASC assayed by RT-PCR and flow cytometry. In contrast, there was a cumulative production of nitric oxide (determined by Griess Reaction) and vascular endothelial growth factor (VEGF; by ELISA) up to 96 h of SS stimulation ( NO(2)(-) in nmol/10(4) cells: static: 0.20 +/- 0.03; SS: 1.78 +/- 0.38, n = 6; VEGF in pg/10(4) cells: static: 191.31 +/- v35.29; SS: 372.80 +/- 46.74, n = 6, P < 0.05). Interestingly, the VEGF production was abrogated by 5 mM N(G)-L-nitro-arginine methyl ester (L-NAME) treatment (VEGF in pg/10(4) cells: SS: 378.80 +/- 46.74, n = 6; SS + L-NAME: 205.84 +/- 91.66, n = 4, P < 0.05). The results indicate that even though SS failed to induce EC surface markers in hASC under the tested conditions, it stimulated NO-dependent VEGF production.
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Introduction: Work disability is a major consequence of rheumatoid arthritis (RA), associated not only with traditional disease activity variables, but also more significantly with demographic, functional, occupational, and societal variables. Recent reports suggest that the use of biologic agents offers potential for reduced work disability rates, but the conclusions are based on surrogate disease activity measures derived from studies primarily from Western countries. Methods: The Quantitative Standard Monitoring of Patients with RA (QUEST-RA) multinational database of 8,039 patients in 86 sites in 32 countries, 16 with high gross domestic product (GDP) (>24K US dollars (USD) per capita) and 16 low-GDP countries (<11K USD), was analyzed for work and disability status at onset and over the course of RA and clinical status of patients who continued working or had stopped working in high-GDP versus low-GDP countries according to all RA Core Data Set measures. Associations of work disability status with RA Core Data Set variables and indices were analyzed using descriptive statistics and regression analyses. Results: At the time of first symptoms, 86% of men (range 57%-100% among countries) and 64% (19%-87%) of women <65 years were working. More than one third (37%) of these patients reported subsequent work disability because of RA. Among 1,756 patients whose symptoms had begun during the 2000s, the probabilities of continuing to work were 80% (95% confidence interval (CI) 78%-82%) at 2 years and 68% (95% CI 65%-71%) at 5 years, with similar patterns in high-GDP and low-GDP countries. Patients who continued working versus stopped working had significantly better clinical status for all clinical status measures and patient self-report scores, with similar patterns in high-GDP and low-GDP countries. However, patients who had stopped working in high-GDP countries had better clinical status than patients who continued working in low-GDP countries. The most significant identifier of work disability in all subgroups was Health Assessment Questionnaire (HAQ) functional disability score. Conclusions: Work disability rates remain high among people with RA during this millennium. In low-GDP countries, people remain working with high levels of disability and disease activity. Cultural and economic differences between societies affect work disability as an outcome measure for RA.
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Neospora caninum is an intracellular parasite that causes major economic impact on cattle raising farms, and infects a wide range of warm-blooded hosts worldwide. Innate immune mechanisms that lead to protection against this parasite are still unknown. In order to investigate whether myeloid differentiation factor 88 (MyD88) is required for resistance against N. caninum, genetically deficient mice (MyD88(-/-)) and wild type littermates were infected with live tachyzoites and the resistance to infection was evaluated. We found that sub-lethal tachyzoite doses induced acute mortality of MyD88(-/-) mice, which succumbed to infection due to uncontrolled parasite replication. Higher parasitism in MyD88(-/-) mice was associated with the lack of IL-12 production by dendritic cells, delayed IFN-gamma responses by NKT, CD4(+) and CD8(+) T lymphocytes, and production of high levels of IL-10. MyD88(-/-) mice replenished with IL-12 and IFN-gamma abolished susceptibility as the animals survived throughout the experimental period. We conclude that protective IFN-gamma-mediated immunity to N. caninum is dependent on initial MyD88 signaling, in a mechanism triggered by production of IL-12 by dendritic cells. Further knowledge on Toll-like receptor recognition of N. caninum antigens is encouraged, since it could generate new prophylactic and therapeutic tools to control parasite burden.
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This study aimed to investigate the immunological mechanisms involved in the gender distinct incidence of paracoccidioidomycosis (pcm), an endemic systemic mycosis in Latin America, which is at least 10 times more frequent in men than in women. Then, we compared the immune response of male and female mice to Paracoccidioides brasiliensis infection, as well as the influence in the gender differences exerted by paracoccin, a P. brasiliensis component with carbohydrate recognition property. High production of Th1 cytokines and T-bet expression have been detected in the paracoccin stimulated cultures of spleen cells from infected female mice. In contrast, in similar experimental conditions, cells from infected males produced higher levels of the Th2 cytokines and expressed GATA-3. Macrophages from male and female mice when stimulated with paracoccin displayed similar phagocytic capability, while fungicidal activity was two times more efficiently performed by macrophages from female mice, a fact that was associated with 50% higher levels of nitric oxide production. In order to evaluate the role of sexual hormones in the observed gender distinction, we have utilized mice that have been submitted to gonadectomy followed by inverse hormonal reconstitution. Spleen cells derived from castrated males reconstituted with estradiol have produced higher levels of IFN-gamma (1291+/-15 pg/mL) and lower levels of IL-10 (494+/-38 pg/mL), than normal male in response to paracoccin stimulus. In contrast, spleen cells from castrated female mice that had been treated with testosterone produced more IL-10 (1284+/-36 pg/mL) and less IFN-gamma (587614 pg/mL) than cells from normal female. In conclusion, our results reveal that the sexual hormones had a profound effect on the biology of immune cells, and estradiol favours protective responses to P. brasiliensis infection. In addition, fungal components, such as paracoccin, may provide additional support to the gender dimorphic immunity that marks P. brasiliensis infection.
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Background Data: Photodynamic therapy (PDT) involves the photoinduction of cytotoxicity using a photosensitizer agent, a light source of the proper wavelength, and the presence of molecular oxygen. A model for tissue response to PDT based on the photodynamic threshold dose (Dth) has been widely used. In this model cells exposed to doses below Dth survive while at doses above the Dth necrosis takes place. Objective: This study evaluated the light Dth values by using two different methods of determination. One model concerns the depth of necrosis and the other the width of superficial necrosis. Materials and Methods: Using normal rat liver we investigated the depth and width of necrosis induced by PDT when a laser with a gaussian intensity profile is used. Different light doses, photosensitizers (Photogem, Photofrin, Photosan, Foscan, Photodithazine, and Radachlorin), and concentrations were employed. Each experiment was performed on five animals and the average and standard deviations were calculated. Results: A simple depth and width of necrosis model analysis allows us to determine the threshold dose by measuring both depth and surface data. Comparison shows that both measurements provide the same value within the degree of experimental error. Conclusion: This work demonstrates that by knowing the extent of the superficial necrotic area of a target tissue irradiated by a gaussian light beam, it is possible to estimate the threshold dose. This technique may find application where the determination of Dth must be done without cutting the tissue.
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Introduction: Treatment of severe bacterial peritonitis, especially by videolaparoscopy, is still a matter of investigation. The aim of the present study was to evaluate the effect of videolaparoscopy and laparotomy access with or without antibiotics on the outcome of severe bacterial peritonitis in rats. Materials and Methods: Sixty-four male Wistar rats were equally assigned to 8 groups: Sham surgery (SHAM), SHAM+antibiotics (SHAM+AB), cecal ligation and puncture (CLP), CLP+AB, CLP+videolaparoscopy (VLAP), CLP+laparotomy (LAP), VLAP+AB, and LAP+AB. All treated animals were submitted to an evaluation of bacteremia, white cell counts, and cytokine determinations: interleukin (IL)-1, IL-6, and tumor necrosis factor-alpha (TNF-alpha). The groups treated with antibiotics received gentamicin and metronidazole. Survival was monitored over a period of 7 days. Results: Peritonitis induced by CLP was severe, with IL-1, IL-6, and TNF-alpha levels and lethality being significantly higher compared to the SHAM group. The IL-6 levels in the VLAP group were significantly higher compared to the CLP and VLAP+AB groups, and the TNF-alpha levels in the VLAP and LAP+AB groups were significantly higher compared to the LAP group. The survival time was significantly higher in the CLP+AB and VLAP+AB groups, when compared to the CLP group. There was no significant difference in bacteremia and lethality rates between the resources employed for treatment of peritonitis. Conclusions: Although the use of laparoscopic access itself exacerbates the inflammatory response, the combination with antibiotics minimizes this effect and increases the survival time. However, all of the resources used for treating severe peritonitis, when applied alone or in combination, have an equivalent influence on bacteremia and lethality rates.
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Purpose: To evaluate the expression of NF-kappa B pathway genes in total bone marrow samples obtained from MM at diagnosis using real-time quantitative PCR and to evaluate its possible correlation with disease clinical features and survival. Material and methods: Expression of eight genes related to NF-kappa B pathway (NFKB1, IKB, RANK, RANKL, OPG, IL6, VCAM1 and ICAM1) were studied in 53 bone marrow samples from newly diagnosed MM patients and in seven normal controls, using the Taqman system. Genes were considered overexpressed when tumor expression level was at least four times higher than that observed in normal samples. Results: The percentages of overexpression of the eight genes were: NFKB1 0%, IKB 22.6%, RANK 15.1%, RANKL 31.3%, OPG 7.5%, IL6 39.6%, VCAM1 10% and ICAM1 26%. We found association between IL6 expression level and International Staging System (ISS) (p = 0.01), meaning that MM patients with high ISS scores have more chance of overexpression of IL6. The mean value of ICAM1 relative expression was also associated with the ISS score (p = 0.02). Regarding OS, cases with IL6 overexpression present worse evolution than cases with IL6 normal expression (p = 0.04). Conclusion: We demonstrated that total bone marrow aspirates can be used as a source of material for gene expression studies in MM. In this context, we confirmed that IL6 overexpression was significantly associated with worse survival and we described that it is associated with high ISS scores. Also, ICAM1 was overexpressed in 26% of cases and its level was associated with ISS scores.