985 resultados para Diffuse Urbanization
Resumo:
E-selectin is expressed by the activated endothelium and its plasma levels are increased in patients with systemic sclerosis. Eighteen patients fulfilling the American Rheumatism Association criteria for systemic sclerosis, 15 females and 3 males, 42-70 years old, 9 with diffuse and 9 with limited forms, were sequentially recruited for this study. Serum E-selectin levels were determined by commercially available ELISA and their association with nailfold capillaroscopic abnormalities was investigated. Nailfold capillaries were analyzed by 16X magnification wide-field capillaroscopy. Two parameters on capillaroscopy were used to correlate to serum E-selectin: deletion and ectasia. Data were analyzed statistically by the Student t-test and Spearman correlation. Two-tailed P values below 0.05 were considered significant. E-selectin range was 38 to 200 ng/ml (80 ± 39.94). There was a correlation between serum E-selectin levels and the deletion capillaroscopic score (r = 0.50, P < 0.035). This correlation was even stronger within the first 48 months of diagnosis (r = 0.63, P < 0.048). On the other hand, no association was observed between selectin and ectasia. Patients with diffuse disease presented higher serum E-selectin levels than patients with limited disease, although the difference was not statistically significant (96.44 ± 48.04 vs 63.56 ± 21.77 ng/dl; P = 0.08). The present study is the first showing a correlation between soluble serum E-selectin levels and alterations in capillaroscopy. The stronger correlation of deletion score in capillaroscopy in early disease suggests that serum E-selectin levels might be a useful biochemical marker of disease activity in systemic sclerosis.
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Multiple sclerosis (MS) is a chronic autoimmune disease of the central nervous system CNS), where inflammation and neurodegeneration lead to irreversible neuronal damage. In MS, a dysfunctional immune system causes auto‐reactive lymphocytes to migrate into CNS where they initiate an inflammatory cascade leading to focal demyelination, axonal degeneration and neuronal loss. One of the hallmarks of neuronal injury and neuroinflammation is the activation of microglia. Activated microglia are found not only in the focal inflammatory lesions, but also diffusely in the normal‐appearing white matter (NAWM), especially in progressive MS. The purine base, adenosine is a ubiquitous neuromodulator in the CNS and also participates in the regulation of inflammation. The effect of adenosine mediated via adenosine A2A receptors has been linked to microglial activation, whereas modulating A2A receptors may exert neuroprotective effects. In the majority of patients, MS presents with a relapsing disease course, later advancing to a progressive phase characterised by a worsening, irreversible disability. Disease modifying treatments can reduce the severity and progression in relapsing MS, but no efficient treatment exists for progressive MS. The aim of this research was to investigate the prevalence of adenosine A2A receptors and activated microglia in progressive MS by using in vivo positron emission tomography (PET) imaging and [11C]TMSX and [11C](R)‐PK11195 radioligands. Magnetic resonance imaging (MRI) with diffusion tensor imaging (DTI) was performed to evaluate structural brain damage. Non‐invasive input function methods were also developed for the analyses of [11C]TMSX PET data. Finally, histopathological correlates of [11C](R)‐PK11195 radioligand binding related to chronic MS lesions were investigated in post‐mortem samples of progressive MS brain using autoradiography and immunohistochemistry. [11C]TMSX binding to A2A receptors was increased in NAWM of secondary progressive MS (SPMS) patients when compared to healthy controls, and this correlated to more severe atrophy in MRI and white matter disintegration (reduced fractional anisotropy, FA) in DTI. The non‐invasive input function methods appeared as feasible options for brain [11C]TMSX images obviating arterial blood sampling. [11C](R)‐PK11195 uptake was increased in the NAWM of SPMS patients when compared to patients with relapsing MS and healthy controls. Higher [11C](R)‐PK11195 binding in NAWM and total perilesional area of T1 hypointense lesions was associated with more severe clinical disability, increased brain atrophy, higher lesion load and reduced FA in NAWM in the MS patients. In autoradiography, increased perilesional [11C](R)‐PK11195 uptake was associated with increased microglial activation identified using immunohistochemistry. In conclusion, brain [11C]TMSX PET imaging holds promise in the evaluation of diffuse neuroinflammation in progressive MS. Being a marker of microglial activation, [11C](R)‐ PK11195 PET imaging could possibly be used as a surrogate biomarker in the evaluation of the neuroinflammatory burden and clinical disease severity in progressive MS.
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Chronic Chagas' disease cardiomyopathy (CCC) is an often fatal outcome of Trypanosoma cruzi infection, with a poorer prognosis than other cardiomyopathies. CCC is refractory to heart failure treatments, and is the major indication of heart transplantation in Latin America. A diffuse myocarditis, plus intense myocardial hypertrophy, damage and fibrosis, in the presence of very few T. cruzi forms, are the histopathological hallmarks of CCC. To gain a better understanding of the pathophysiology of CCC, we analyzed the protein profile in the affected CCC myocardium. Homogenates from left ventricular myocardial samples of end-stage CCC hearts explanted during heart transplantation were subjected to two-dimensional electrophoresis with Coomassie blue staining; protein identification was performed by MALDI-ToF mass spectrometry and peptide mass fingerprinting. The identification of selected proteins was confirmed by immunoblotting. We demonstrated that 246 proteins matched in gels from two CCC patients. They corresponded to 112 distinct proteins. Along with structural/contractile and metabolism proteins, we also identified proteins involved in apoptosis (caspase 8, caspase 2), immune system (T cell receptor ß chain, granzyme A, HLA class I) and stress processes (heat shock proteins, superoxide dismutases, and other oxidative stress proteins). Proteins involved in cell signaling and transcriptional factors were also identified. The identification of caspases and oxidative stress proteins suggests the occurrence of active apoptosis and significant oxidative stress in CCC myocardium. These results generated an inventory of myocardial proteins in CCC that should contribute to the generation of hypothesis-driven experiments designed on the basis of the classes of proteins identified here.
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The two main objectives of Bayesian inference are to estimate parameters and states. In this thesis, we are interested in how this can be done in the framework of state-space models when there is a complete or partial lack of knowledge of the initial state of a continuous nonlinear dynamical system. In literature, similar problems have been referred to as diffuse initialization problems. This is achieved first by extending the previously developed diffuse initialization Kalman filtering techniques for discrete systems to continuous systems. The second objective is to estimate parameters using MCMC methods with a likelihood function obtained from the diffuse filtering. These methods are tried on the data collected from the 1995 Ebola outbreak in Kikwit, DRC in order to estimate the parameters of the system.
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Gastric cancer is the forth most frequent malignancy and the second most common cause of cancer death worldwide. DNA methylation is the most studied epigenetic alteration, occurring through a methyl radical addition to the cytosine base adjacent to guanine. Many tumor genes are inactivated by DNA methylation in gastric cancer. We evaluated the DNA methylation status of ANAPC1, CDKN2A and TP53 by methylation-specific PCR in 20 diffuse- and 26 intestinal-type gastric cancer samples and 20 normal gastric mucosa in individuals from Northern Brazil. All gastric cancer samples were advanced stage adenocarcinomas. Gastric samples were surgically obtained at the João de Barros Barreto University Hospital, State of Pará, and were stored at -80°C before DNA extraction. Patients had never been submitted to chemotherapy or radiotherapy, nor did they have any other diagnosed cancer. None of the gastric cancer samples presented methylated DNA sequences for ANAPC1 and TP53. CDKN2A methylation was not detected in any normal gastric mucosa; however, the CDKN2A promoter was methylated in 30.4% of gastric cancer samples, with 35% methylation in diffuse-type and 26.9% in intestinal-type cancers. CDKN2A methylation was associated with the carcinogenesis process for ~30% diffuse-type and intestinal-type compared to non-neoplastic samples. Thus, ANAPC1 and TP53 methylation was probably not implicated in gastric carcinogenesis in our samples. CDKN2A can be implicated in the carcinogenesis process of only a subset of gastric neoplasias.
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Fifteen symptomatic and seven asymptomatic dogs infected naturally with Leishmania chagasi were examined in order to identify the presence of parasites and changes in heart and lung. Histopathological, cytological, and immunohistochemical analyses were performed on samples of heart and lung tissues. An inflammatory reaction characterized by inflammatory mononuclear, perivascular and intermuscular infiltrates was observed in both symptomatic and asymptomatic animals on histopathological analysis of the heart. In the lung, there was thickening of the alveolar septa due to congestion, edema, inflammatory infiltrate, and fibroblast proliferation. A focal reaction was observed although a diffuse reaction was present in both groups. On cytological examination, heart and lung imprints revealed amastigotes in two symptomatic animals and heart imprints were found in 1 asymptomatic dog. Immunoperoxidase staining showed amastigotes in the lung and heart of only 1 of 6 symptomatic animals examined. Within the ethical principles and limits of this research, it can be inferred that the study of heart and lung alterations in canine visceral leishmaniasis is increasingly important for understanding the problem related to humans. Dogs with visceral leishmaniasis were a good experimental model, since infection was caused by the same agent and the animals developed clinical, pathological and immunological alterations similar to those observed in humans.
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The objective of the present study was to describe motor behavioral changes in association with histopathological and hematological findings in Wistar rats inoculated intravenously with human T-cell lymphotropic virus type 1 (HTLV-1)-infected MT2 cells. Twenty-five 4-month-old male rats were inoculated with HTLV-1-infected MT2 cells and 13 control rats were inoculated with normal human lymphocytes. The behavior of the rats was observed before and 5, 10, 15, and 20 months after inoculation during a 30-min/rat testing time for 5 consecutive days. During each of 4 periods, a subset of rats was randomly chosen to be sacrificed in order to harvest the spinal cord for histopathological analysis and to obtain blood for serological and molecular studies. Behavioral analyses of the HTLV-1-inoculated rats showed a significant decrease of climbing, walking and freezing, and an increase of scratching, sniffing, biting, licking, and resting/sleeping. Two of the 25 HTLV-1-inoculated rats (8%) developed spastic paraparesis as a major behavioral change. The histopathological changes were few and mild, but in some cases there was diffuse lymphocyte infiltration. The minor and major behavioral changes occurred after 10-20 months of evolution. The long-term observation of Wistar rats inoculated with HTLV-1-infected MT2 cells showed major (spastic paraparesis) and minor motor abnormalities in association with the degree of HTLV-1-induced myelopathy.
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Autosomal dominant polycystic kidney disease (ADPKD) is one of the most common human life-threatening monogenic disorders. The disease is characterized by bilateral, progressive renal cystogenesis and cyst and kidney enlargement, often leading to end-stage renal disease, and may include extrarenal manifestations. ADPKD is caused by mutation in one of two genes, PKD1 and PKD2, which encode polycystin-1 (PC1) and polycystin-2 (PC2), respectively. PC2 is a non-selective cation channel permeable to Ca2+, while PC1 is thought to function as a membrane receptor. The cyst cell phenotype includes increased proliferation and apoptosis, dedifferentiation, defective planar polarity, and a secretory pattern associated with extracellular matrix remodeling. The two-hit model for cyst formation has been recently extended by the demonstration that early gene inactivation leads to rapid and diffuse development of renal cysts, while inactivation in adult life is followed by focal and late cyst formation. Renal ischemia/reperfusion, however, can function as a third hit, triggering rapid cyst development in kidneys with Pkd1 inactivation induced in adult life. The PC1-PC2 complex behaves as a sensor in the primary cilium, mediating signal transduction via Ca2+ signaling. The intracellular Ca2+ homeostasis is impaired in ADPKD, being apparently responsible for the cAMP accumulation and abnormal cell proliferative response to cAMP. Activated mammalian target for rapamycin (mTOR) and cell cycle dysregulation are also significant features of PKD. Based on the identification of pathways altered in PKD, a large number of preclinical studies have been performed and are underway, providing a basis for clinical trials in ADPKD and helping the design of future trials.
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Because the superficial lymphatics in the lungs are distributed in the subpleural, interlobular and peribroncovascular interstitium, lymphatic impairment may occur in the lungs of patients with idiopathic interstitial pneumonias (IIPs) and increase their severity. We investigated the distribution of lymphatics in different remodeling stages of IIPs by immunohistochemistry using the D2-40 antibody. Pulmonary tissue was obtained from 69 patients with acute interstitial pneumonia/diffuse alveolar damage (AIP/DAD, N = 24), cryptogenic organizing pneumonia/organizing pneumonia (COP/OP, N = 6), nonspecific interstitial pneumonia (NSIP/NSIP, N = 20), and idiopathic pulmonary fibrosis/usual interstitial pneumonia (IPF/UIP, N = 19). D2-40+ lymphatic in the lesions was quantitatively determined and associated with remodeling stage score. We observed an increase in the D2-40+ percent from DAD (6.66 ± 1.11) to UIP (23.45 ± 5.24, P = 0.008) with the advanced process of remodeling stage of the lesions. Kaplan-Meier survival curves showed a better survival for patients with higher lymphatic D2-40+ expression than 9.3%. Lymphatic impairment occurs in the lungs of IIPs and its severity increases according to remodeling stage. The results suggest that disruption of the superficial lymphatics may impair alveolar clearance, delay organ repair and cause severe disease progress mainly in patients with AIP/DAD. Therefore, lymphatic distribution may serve as a surrogate marker for the identification of patients at greatest risk for death due to IIPs.
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Idiopathic interstitial pneumonias include complex diseases that have a strong interaction between genetic makeup and environmental factors. However, in many cases, no infectious agent can be demonstrated, and these clinical diseases rapidly progress to death. Theoretically, idiopathic interstitial pneumonias could be caused by the Epstein-Barr virus, cytomegalovirus, adenovirus, hepatitis C virus, respiratory syncytial virus, and herpesvirus, which may be present in such small amounts or such configuration that routine histopathological analysis or viral culture techniques cannot detect them. To test the hypothesis that immunohistochemistry provides more accurate results than the mere histological demonstration of viral inclusions, this method was applied to 37 open lung biopsies obtained from patients with idiopathic interstitial pneumonias. As a result, immunohistochemistry detected measles virus and cytomegalovirus in diffuse alveolar damage-related histological patterns of acute exacerbation of idiopathic pulmonary fibrosis and nonspecific interstitial pneumonia in 38 and 10% of the cases, respectively. Alveolar epithelium infection by cytomegalovirus was observed in 25% of organizing pneumonia patterns. These findings were coincident with nuclear cytopathic effects but without demonstration of cytomegalovirus inclusions. These data indicate that diffuse alveolar damage-related cytomegalovirus or measles virus infections enhance lung injury, and a direct involvement of these viruses in diffuse alveolar damage-related histological patterns is likely. Immunohistochemistry was more sensitive than the histological demonstration of cytomegalovirus or measles virus inclusions. We concluded that all patients with diffuse alveolar damage-related histological patterns should be investigated for cytomegalovirus and measles virus using sensitive immunohistochemistry in conjunction with routine procedures.
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Membranous nephropathy (MN), characterized by the presence of diffuse thickening of the glomerular basement membrane and subepithelial in situimmune complex disposition, is the most common cause of idiopathic nephrotic syndrome in adults, with an incidence of 5-10 per million per year. A number of studies have confirmed the relevance of several experimental insights to the pathogenesis of human MN, but the specific biomarkers of MN have not been fully elucidated. As a result, our knowledge of the alterations in histone methylation in MN is unclear. We used chromatin immunoprecipitation followed by high-throughput sequencing (ChIP-seq) to analyze the variations in a methylated histone (H3K9me3) in peripheral blood mononuclear cells from 10 MN patients and 10 healthy subjects. There were 108 genes with significantly different expression in the MN patients compared with the normal controls. In MN patients, significantly increased activity was seen in 75 H3K9me3 genes, and decreased activity was seen in 33, compared with healthy subjects. Five positive genes, DiGeorge syndrome critical region gene 6 (DGCR6), sorting nexin 16 (SNX16), contactin 4 (CNTN4), baculoviral IAP repeat containing 3 (BIRC3), and baculoviral IAP repeat containing 2 (BIRC2), were selected and quantified. There were alterations of H3K9me3 in MN patients. These may be candidates to help explain pathogenesis in MN patients. Such novel findings show that H3K9me3 may be a potential biomarker or promising target for epigenetic-based MN therapies.
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This study aimed to explore the correlations between cadherin-17 (CDH17) protein expression and the clinicopathological features and prognosis of patients with sporadic gastric cancer (GC). Nine relevant studies of 1,960 patients were identified using electronic database searches supplemented with a manual search in strict accordance with inclusion and exclusion criteria. Statistical analyses were conducted using STATA 12.0 statistical software. Relative risks and 95% confidence intervals were determined, and Z test was used to measure the significance of the overall effect size. A total of nine eligible cohort studies were included in this meta-analysis. The expression of CDH17 in patients with diffuse GC was significantly higher than in those with intestinal-type GC. Moreover, the tumor depth of invasion differed significantly between patients with positive CDH17 (CDH17+) and negative CDH17 (CDH17-) GC. However, there were no significant differences between CDH17+ and CDH17- GC patients with respect to tumor node metastasis clinical stages, histological grades, or lymph node metastasis. Despite the differences in invasive depth, there was no significant difference in 5-year survival rates between CDH17+ and CDH17- GC patients. Our meta-analysis provides evidence that CDH17 protein expression may be associated with the development of GC, suggesting that CDH17 is an important biomarker that could be useful for the early diagnosis of GC. However, CDH17 levels do not appear to impact overall survival.
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INTRODUCTION: C4d is a marker of antibody-mediated rejection (ABMR) in kidney allografts, although cellular rejection also have C4d deposits. OBJECTIVE: To correlate C4d expression with clinico-pathological parameters and graft outcomes at three years. METHODS: One hundred forty six renal transplantation recipients with graft biopsies by indication were included. C4d staining was performed by paraffin-immunohistochemistry. Graft function and survival were measured, and predictive variables of the outcome were determined by multivariate Cox regression. RESULTS: C4d staining was detected in 48 (31%) biopsies, of which 23 (14.7%) had diffuse and 25 (16%) focal distribution. Pre-transplantation panel reactive antibodies (%PRA) class I and II were significantly higher in C4d positive patients as compared to those C4d negative. Both glomerulitis and pericapillaritis were associated to C4d (p = 0.002 and p < 0.001, respectively). The presence of C4d in biopsies diagnosed as no rejection (NR), acute cellular rejection (ACR) or interstitial fibrosis/ tubular atrophy (IF/TA) did not impact graft function or survival. Compared to NR, ACR and IF/TA C4d-, patients with ABMR C4d+ had the worst graft survival over 3 years (p = 0.034), but there was no difference between ABMR versus NR, ACR and IF/TA that were C4d positive (p = 0.10). In Cox regression, graft function at biopsy and high %PRA levels were predictors of graft loss. CONCLUSIONS: This study confirmed that C4d staining in kidney graft biopsies is a clinically useful marker of ABMR, with well defined clinical and pathological correlations. The impact of C4d deposition in other histologic diagnoses deserves further investigation.
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Addressing rural development discussions in Brazil: context and issues of debate. The work analyzes the main theoretical trends and subjects that integrate the recent Brazilian debate about rural development. We agued that the agenda of the rural development in Brazil, on which actively participate scholars, organizations and institutions, have been formulated by the State and the public politics implemented since the beginning of the 1990. Among the factors that had influenced the emergency of the debate about rural development is distinguished the increasing social and political legitimating of family farming and the agrarian reform, the reorientation of the state policies, the increasing sharply political and ideological quarrels with the agribusiness wing and the matters about sustainability. It is also argued that the analytical and interpretative references that have being used by the scholars are still diffuse and varied, but has been capable to influence the policy makers.
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Lipid movement in cells occurs by a variety of methods. Lipids diffuse freely along the lateral plane of a membrane and can translocate between the lipid leaflets, either spontaneously or with the help of enzymes. Lipid translocation between the different cellular compartments predominantly takes place through vesicular transport. Specialized lipid transport proteins (LTPs) have also emerged as important players in lipid movement, as well as other cellular processes. In this thesis we have studied the glycolipid transport protein (GLTP), a protein that transports glycosphingolipids (GSLs). While the in vitro properties of GLTP have been well characterized, its cell biological role remains elusive. By altering GSL and GLTP levels in cells, we have extracted clues towards the protein's function. Based on the results presented in this thesis and in previous works, we hypothesize that GLTP is involved in the GSL homeostasis in cells. GLTP most likely functions as a transporter or sensor of newly synthesized glucosylceramide (GlcCer), at or near the site of GlcCer synthesis. GLTP also seems to be involved in the synthesis of globotriacylceramide, perhaps in a manner that is similar to that of the fourphosphate adaptor protein 2, another GlcCer-transporting LTP. Additionally, we have developed and studied a novel method of introducing ceramides to cells, using a solvent-free approach. Ceramides are important lipids that are implicated in several cellular functions. Their role as proapoptotic molecules is particularly evident. Ceramides form stable bilayer structures when complexed with cholesterol phosphocholine (CholPC), a large-headgroup sterol. By adding ceramide/CholPC complexes to the growth medium, various chain length ceramides were successfully delivered to cells in culture. The uptake rate was dependent on the chain length of the ceramide, where shorter lipids were internalized more quickly. The rate of uptake also determined how the cells metabolised the ceramides. Faster uptake favored conversion of ceramide to GlcCer, whereas slower delivery resulted mainly in breakdown of the lipid.