220 resultados para Benign liver tumor


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Activation of the immune response in hantavirus cardiopulmonary syndrome (HCPS) leads to a high TNF production, probably contributing to the disease. The polymorphic TNF2 allele (TNF -308G/A) has been associated with increased cytokine production. We investigated the association of the TNF2 allele with the outcome of hantavirus infection in Brazilian patients. A total of 122 hantavirus-exposed individuals (26 presenting HCPS and 96 only hantavirus seroconversion) were studied. The TNF2 allele was more frequently found in HCPS patients than in individuals with positive serology for hantavirus but without a history of HCPS illness, suggesting that the TNF2 allele could represent a risk factor for developing HCPS.

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Oral squamous Cell carcinoma (OSCC) is the most common head and neck cancer. Only in Brazil, the estimate is for 14,160 new cases in 2009. HPV is associated with increasing risk of oral cancer, but its role in carcinogenesis is still controversial. BUBR1, all important protein in the mitotic spindle assembly checkpoint (SAC), has been associated with some virus-encoded proteins and cancer. The aim of the present study was to evaluate the expression of BUBR1 in non-malignant oral lesions and OSCC with and without metastasis associated with HPV infection. We performed immunohistochemistry for BUBR1 in 70 OSCC biopsies divided into three groups (in situ tumors, invasive tumors without metastasis and invasive tumors with metastasis) with their respective lymph nodes from samples with metastasis and in 16 non-malignant oral lesions. PCR was performed in order to detect HPV DNA. Significantly higher BUBR1 expression associated with shorter survival (p=0.0479) was observed in malignant lesions. There was also it significant correlation (r=1.000) with BUBR1 expression in lesions with metastasis and their lymph nodes. Ninety percent of OSCC and 100% of benign lesions were HPV positive. HPV16 and HVP18 were present in 13 and 24% of HPV-positive OSCC samples, respectively. HPV was more prevalent (76%) in samples with a high BUBR1 expression and the absence of viral DNA had no influence oil BUBR1 expression. These findings suggest that HPV could be associated with overexpression of BUBR1 in OSCC. but not in benign oral lesions.

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Oxidative stress and lipid peroxidation, associated with ethanol, are considered important pathogenic mechanisms in the formation of hepatic steatosis. The objective of the present study was to assess the effects of supplementation with lecithin and vitamin E on the oxidatives stress and hepatic steatosis induced in rats by chronic ethanol consumption. Fifty-two Wistar rats were divided into 4 experimental groups: control (AIN-93 diet), ethanol group (control diet plus a 20% hydroalcoholic solution), ethanol + vitamin E group (addition of 0.6% vitamin E to the diet plus a 20% hydroalcoholic solution); ethanol + soy lecithin group (addition of 5 % soy lecithin to the diet plus a 20% hydroalcoholic solution). At the end of 4 weeks the animals were sacrificed. The results showed a significantly smaller number of animals (p < 0.05) classified as having a low degree of steatosis in the ethanol + vitamin E group and ethanol + soy lecithin group compared to the ethanol group. In addition, the ethanol + soy lecithin group had a significantly lower concentration of hepatic fat (p < 0.05) than the ethanol group. A significant reduction of hepatic TBARS concentration (p < 0.05) was detected in the ethanol + vitamin E group compared to the ethanol group. Hepatic carbonyl concentration was significantly lower in the ethanol + soy lecithin group. However, hepatic GSH was significantly lower in the ethanol + vitamin E and ethanol + soy lecithin groups compared to the control group. In conclusion, supplementation with lecithin and vitamin E attenuated the hepatotoxic effects of chronic ethanol intake and contributed to a reduction of the progression of steatosis status.

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Although patterns of somatic alterations have been reported for tumor genomes, little is known on how they compare with alterations present in non-tumor genomes. A comparison of the two would be crucial to better characterize the genetic alterations driving tumorigenesis. We sequenced the genomes of a lymphoblastoid (HCC1954BL) and a breast tumor (HCC1954) cell line derived from the same patient and compared the somatic alterations present in both. The lymphoblastoid genome presents a comparable number and similar spectrum of nucleotide substitutions to that found in the tumor genome. However, a significant difference in the ratio of non-synonymous to synonymous substitutions was observed between both genomes (P = 0.031). Protein-protein interaction analysis revealed that mutations in the tumor genome preferentially affect hub-genes (P = 0.0017) and are co-selected to present synergistic functions (P < 0.0001). KEGG analysis showed that in the tumor genome most mutated genes were organized into signaling pathways related to tumorigenesis. No such organization or synergy was observed in the lymphoblastoid genome. Our results indicate that endogenous mutagens and replication errors can generate the overall number of mutations required to drive tumorigenesis and that it is the combination rather than the frequency of mutations that is crucial to complete tumorigenic transformation.

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Microarray gene expression profiling is a high-throughput system used to identify differentially expressed genes and regulation patterns, and to discover new tumor markers. As the molecular pathogenesis of meningiomas and schwannomas, characterized by NF2 gene alterations, remains unclear and suitable molecular targets need to be identified, we used low density cDNA microarrays to establish expression patterns of 96 cancer-related genes on 23 schwannomas, 42 meningiomas and 3 normal cerebral meninges. We also performed a mutational analysis of the NF2 gene (PCR, dHPLC, Sequencing and MLPA), a search for 22q LOH and an analysis of gene silencing by promoter hypermethylation (MS-MLPA). Results showed a high frequency of NF2 gene mutations (40%), increased 22q LOH as aggressiveness increased, frequent losses and gains by MLPA in benign meningiomas, and gene expression silencing by hypermethylation. Array analysis showed decreased expression of 7 genes in meningiomas. Unsupervised analyses identified 2 molecular subgroups for both meningiomas and schwannomas showing 38 and 20 differentially expressed genes, respectively, and 19 genes differentially expressed between the two tumor types. These findings provide a molecular subgroup classification for meningiomas and schwannomas with possible implications for clinical practice.

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von Hippel-Lindau (VHL) disease is an autosomal dominant hereditary cancer syndrome that predisposes to the development of a variety of benign and malignant tumours, especially cerebellar haemangioblastomas, retinal angiomas and clear-cell renal cell carcinomas (RCC). The etiology and manifestations are due to germline and somatic mutations in the VHL tumour suppressor gene. VHL disease is classified into type 1 and type 2, showing a clear genotype-phenotype correlation, as type 2 is associated with phaeochromocytoma and essentially caused by missense mutations. The aim of this study is to characterize the phenotype and genotype of families with VHL disease. Eighteen of twenty patients from ten unrelated families underwent genetic testing, nine of them fulfilled VHL disease criteria and one had an apparently sporadic cerebellar haemangioblastoma. Four different germline mutations in the VHL gene were identified: c.226_228delTTC (p.Phe76del); c.217C > T (p.Gln73X); IVS1-1 G > A and IVS2-1 G > C. The first three mutations were associated with type 1 disease and the last one with type 2B, which had never been identified in the germline. The transcriptional processing of a novel splice-site mutation was characterised. Three type 1 VHL families showed large deletions of the VHL gene, two of them encompassed the FANCD2/C3orf10 genes and were not associated with renal lesions. We also suggest that such families should be subclassified according to the risk of RCC and the extent of the VHL gene deletions. This study highlights the need for a through clinical and molecular characterisation of families with VHL disease to better delineate its genotype-phenotype correlation.

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Oxidative stress plays an important role in the development of cognitive impairment in sepsis. Here we assess the effects of acute and extended administration of cannabidiol (CBD) on oxidative stress parameters in peripheral organs and in the brain, cognitive impairment, and mortality in rats submitted to sepsis by cecal ligation and perforation (CLP). To this aim, male Wistar rats underwent either sham operation or CLP. Rats subjected to CLP were treated by intraperitoneal injection with ""basic support"" and CBD (at 2.5, 5, or 10 mg/kg once or daily for 9 days after CLP) or vehicle. Six hours after CLP (early times), the rats were killed and samples from lung, liver, kidney, heart, spleen, and brain (hippocampus, striatum, and cortex) were obtained and assayed for thiobarbituric acid reactive species (TBARS) formation and protein carbonyls. On the 10th day (late times), the rats were submitted to the inhibitory avoidance task. After the test, the animals were killed and samples from lung, liver, kidney, heart, spleen, and brain (hippocampus) were obtained and assayed for TBARS formation and protein carbonyls. The acute and extended administration of CBD at different doses reduced TBARS and carbonyl levels in some organs and had no effects in others, ameliorated cognitive impairment, and significantly reduced mortality in rats submitted to CLP. Our data provide the first experimental demonstration that CBD reduces the consequences of sepsis induced by CLP in rats, by decreasing oxidative stress in peripheral organs and in the brain, improving impaired cognitive function, and decreasing mortality. (C) 2010 Elsevier B.V. All rights reserved.

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Mucin 1 (MUC1) is a glycoprotein that is expressed on apical cell membranes in a variety of normal tissues. MUC1 is involved in cell signaling, inhibition of cell-cell and cell matrix adhesion, apoptosis, proliferation, and transcription. Hypoxia is an important factor that promotes cancer metastasis and stimulates angiogenesis and tumor progression. Hypoxia inducible factor 1 (HIF-1 alpha) and carbonic anhydrase IX (CAIX) are two molecules that are involved in this process. The role of hypoxia in MUC1+ invasive ductal breast carcinomas is not well established. In this study, the expression of MUC1 was correlated with the hypoxia-associated markers HIF-1 alpha and CAIX, as well as several immunohistochemical markers and clinicopathologic features of prognostic significance in 243 invasive ductal carcinomas. MUC1 was overexpressed in 37.0% of patients and correlated with the expression of estrogen receptor (p = 0.0001), progesterone receptor (p = 0.0001), HIF-1 alpha (p = 0.006), VEGF (p = 0.024), and p53 (p = 0.025). In breast cancer, MUC1 expression has been associated with increased degradation of inhibitor of NF-kappa B (I kappa B alpha), driving NF-kappa B to the nucleus and blocking apoptosis and promoting cell survival. We analyzed NF-kappa B expression in MUC1+ breast carcinoma and found a very significant relationship between these proteins (p = 0.0001). Our findings indicate that MUC1 may play a role in the regulation of hormone receptors by increasing the inactivation of p53 and targeting NF-kappa B to the nucleus. Our data also support the notion that activation of HIF-1 alpha in MUC1+ breast carcinomas may modulate VEGF expression, allowing a metabolic adaptation to hypoxia.

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The prevalence of cigarette smoking (CS) is increased among obese subjects, who are susceptible to develop nonalcoholic fatty liver disease (NAFLD). We investigated the hepatic effects of CS in control and obese rats. Control and obese Zucker rats were divided into smokers and nonsmokers (n = 12 per group). Smoker rats were exposed to 2 cigarettes/day, 5 days/week for 4 weeks. The effects of CS were assessed by biochemical analysis, hepatic histological examination, immunohistochemistry, and gene expression analysis. Phosphorylation of AKT and extracellular signal-regulated kinase (ERK) and quantification of carbonylated proteins were assessed by western blotting. As expected, obese rats showed hypercholesterolemia, insulin resistance, and histological features of NAFLD. Smoking did not modify the lipidic or glucidic serum profiles. Smoking increased alanine aminotransferase serum levels and the degree of liver injury in obese rats, whereas it only induced minor changes in control rats. Importantly, CS increased the histological severity of NAFLD in obese rats. We also explored the potential mechanisms involved in the deleterious effects of CS. Smoking increased the degree of oxidative stress and hepatocellular apoptosis in obese rats, but not in controls. Similarly, smoking increased the hepatic expression of tissue inhibitor of metalloproteinase-1 and procollagen-alpha2(I) in obese rats, but not in controls. Finally, smoking regulated ERK and AKT phosphorylation. The deleterious effects of CS were not observed after a short exposure (5 days). Conclusion: CS causes oxidative stress and worsens the severity of NAFLD in obese rats. Further studies should assess whether this finding also occurs in patients with obesity and NAFLD. (HEPATOLOGY 2010;51:1567-1576.)

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Paracoccidioides brasiliensis infection causes a systemic mycosis originally described in Latin America but with Current reports of worldwide distribution. The clinical presentation of paracoccidiodomycosis as an isolated long-bone lesion in children is quite unusual. This article describes a 10-year-old male with a lytic femoral bone lesion caused by P. brasiliensis infection that was first suspected of being of neoplasic etiology. The text also emphasizes the importance of including endemic fungal infections in the differential diagnosis of bone lesions.

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Background Little progress has been made to identify the central neuroendocrine pathway involved in the energy intake control in nonalcoholic fatty liver disease (NAFLD) patients. Objective To assess the influence of orexigenic neuropeptides in the nutritional aspects of NAFLD obese adolescents submitted to a long-term interdisciplinary approach. Methods Fifty adolescents aged 15-19 years, with body mass index at least 95th percentile, consisting of 25 patients without NAFLD and 25 with NAFLD. The NAFLD diagnosis was determined by ultrasonography. Blood samples were collected to analyze glycemia, hepatic transaminases, and lipid profile. Insulin resistance was estimated by Homeostasis Model Assessment Insulin Resistance Index. Neuropeptide Y (NPY) and agouti related protein concentrations were measured by enzyme-linked immunosorbent assay. Analyses of food intake were made by 3 days recordatory inquiry. Results At baseline conditions, the patients with NAFLD had significantly higher values of body mass, body mass index, visceral fat, triglycerides, VLDL-C, and hepatic transaminases. After the long-term intervention, they presented a significant reduction in these parameters. In both the groups, it was observed a significant decrease in energy intake, macronutrients and dietetic cholesterol. Only the patients with NAFLD presented a positive correlation between the saturated fatty acids intake and the orexigenic neuropeptides NPY and agouti related protein, and carbohydrate with NPY. Indeed, it was observed a positive correlation between energy intake, lipid (%) and saturated fatty acids with visceral fat accumulation. Conclusion Our findings showed an important influence of diet composition in the orexigenic system, being essential consider that the excessive saturated fatty acids intake could be a determinant factor to increase nonalcoholic fatty liver disease. Eur J Gastroenterol Hepatol 22:557-563 (C) 2010 Wolters Kluwer Health | Lippincott Williams & Wilkins.

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The differential diagnosis of renal tumors, particularly in adolescents, may be challenging. We describe an 11-year-old female with a primary intra-renal mass. Initial differential diagnoses included primitive neuroectodermal tumor (PNET), desmoplastic small round cell tumor (DSRCT), and Wilms Turner (WT). Extensive pathologic and molecular analysis on initial and relapsed tumor samples confirmed WT. The EWS-WTI and EWS-FL11 rearrange-merits, distinctive of DSRCT and PNET were negative. The differential diagnosis on monophasic blastemal WT may be complex. Primary renal DSRCT and MET have been rarely described. Nevertheless, molecular confirmation for these rare conditions may be necessary in selected cases. Pediatr Blood Cancer 2010;54:3 19-321. (C) 2009 Wiley-Liss, Inc.

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Methionine-choline-deficient diet represents a model for the study of the pathogenesis of steatohepatitis. Male rats were divided into three groups, the first group receiving a control diet and the other two groups receiving a methionine-choline-deficient diet for 1 month (MCD1) and for 2 months (MCD2), respectively. The livers of the animals were collected for the determination of vitamin E, thiobarbituric acid reactive substances (TBARS), GSH concentration, DNA damages, and for histopathological evaluation. The hepatic TBARS and GSH content was higher (P < 0.05) in the groups receiving the experimental diet (MCD1 and MCD2) compared to control diet, and hepatic vitamin E concentration differed (P < 0.05) between the MCD1 and MCD2 groups, with the MCD2 group presenting a lower concentration. Damage to hepatocyte DNA was greater (P < 0.05) in the MCD2 group (262.80 DNA injuries/100 hepatocytes) compared to MCD1 (136.4 DNA injuries/100 hepatocytes) and control diet (115.83 DNA injuries/100 hepatocytes). Liver histopathological evaluation showed that steatosis, present in experimental groups was micro- and macro-vesicular and concentrated around the centrolobular vein, zone 3, with preservation of the portal space. The inflammatory infiltrate was predominantly periductal and the steatosis and inflammatory infiltrate was similar in the MCD1 and MCD2 groups, although the presence of Mallory bodies was greater in the MCD2 group. The study describes the contribution of a methionine-choline-deficient diet to the progression of steatosis, lipid peroxidation and hepatic DNA damage in rats, serving as a point of reflection about the role of these nutrients in the western diet and the elevated non-alcoholic steatohepatitis rates in humans.

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Background: The tumor necrosis factor (TNF) gene is located within the highly polymorphic major histocompatibility complex region, exhibiting the -308 CA promoter region polymorphism and six microsatellites (TNFa-f) spanning the region nearby the TNF locus. Objective: In the present Study, we evaluated the frequency of -308 CA and TNFa-e polymorphisms and respective haplotypes (in chromosomal sequence: TNFd-TNFe-308GA-TNFc-TNFa-TNFb), in 222 patients with AIDS, 52 of whom exhibited cytomegalovirus retinitis, and in 202 healthy HIV-negative individuals. Method: TNF microsatellite and single nucleotide polymorphism typings were performed by PCR followed by polyacrylamide gel electrophoresis. Results: The TNF-308A allele and the 4-3-C-2-7-1 haplotype were associated with susceptibility to AIDS, whereas the TNFb4 allele and the 3-3-C-1-11-4 haplotype were associated with protection against AIDS development. The TNFc2 allele and the 4-1-G-2-2-1 haplotype, which contains the TNFc2 allele, were associated with cytomegalovirus retinitis. Conclusion: This study highlights that polymorphic sites spanning the region nearby the TNF locus are associated with AIDS per se and with cytomegalovirus retinitis in AIDS patients. (C) 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins

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Ischemia and reperfusion injury (IRI) contributes to the development of chronic interstitial fibrosis/tubular atrophy in renal allograft patients, Cyclooxygenase (COX) 1 and 2 actively participate in acute ischemic injury by activating endothelial cells and inducing oxidative stress. Furthermore, blockade of COX I and 2 has been associated with organ improvement after ischemic damage. The aim of this study was to evaluate the role of COX I and 2 in the development of fibrosis by performing a COX I and 2 blockade immediately before IRI We subjected C57BI/6 male mice to 60 min of unilateral renal pedicle occlusion, Prior to surgery mice were either treated with indomethacin (IMT) at days -1 and 0 or were untreated. Blood and kidney samples were collected 6 wks after IRI. Kidney samples were analyzed by real-time reverse transcription-poly me rase chain reaction for expression of transforming growth factor beta (TGF-beta), monocyte chemoattractant protein 1 (MCP-1), osteopontin (OPN), tumor necrosis factor alpha (TNF-alpha), interleukin (IL)-1 beta, IL-10, heme oxygenose 1 (HO-1), vimentin, connective-tissue growth factor (CTGF), collagen 1, and bone morphogenic protein 7 (BMP-7), To assess tissue fibrosis we performed morphometric analyses and Sirius red staining. We also performed immunohistochemical analysis of anti-actin smooth muscle, Renal function did not significantly differ between groups. Animals pretreated with IMT showed significantly less interstitial fibrosis than nontreated animals. Gene transcript analyses showed decreased expression of TGF-beta, MCP-1,TNF-alpha, IL-1-beta, vimentin, collagen 1, CTGF and IL-10 mRNA (all P < 0.05), Moreover, HO-I mRNA was increased in animals pretreated with IMT (P < 0.05) Conversely, IMT treatment decreased osteopontin expression and enhanced BMP-7 expression, although these levels did rot reach statistical significance when compared with control expression levels, I he blockade of COX 1 and 2 resulted in less tissue fibrosis, which was associated with a decrease in proinflammatory cytokines and enhancement of the protective cellular response.