908 resultados para Major Promastigotes


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One consistent functional imaging finding from patients with major depression has been abnormality of the anterior cingulate cortex (ACC). Hypoperfusion has been most commonly reported, but some studies suggest relative hyperperfusion is associated with response to somatic treatments. Despite these indications of the possible importance of the ACC in depression there have been relatively few cognitive studies ACC function in patients with major depression. The present study employed a series of reaction time (RT) tasks involving selection with melancholic and nonmelancholic depressed patients, as well as age-matched controls. Fifteen patients with unipolar major depression (7 melancholic, 8 nonmelancholic) and 8 healthy age-matched controls performed a series of response selection tasks (choice RT, spatial Stroop, spatial stimulus-response compatibility (SRC), and a combined Stroop + SRC condition). Reaction time and error data were collected. Melancholic patients were significantly slower than controls on all tasks but were slower than nonmelancholic patients only on the Stroop and Stroop + SRC conditions. Nonmelancholic patients did not differ from the control group on any task. The Stroop task seems crucial in differentiating the two depressive groups, they did not differ on the choice RT or SRC tasks. This may reflect differential task demands, the SRC involved symbolic manipulation that might engage the dorsal ACC and dorsolateral prefrontal cortex (DLPFC) to a greater extent than the, primarily inhibitory, Stroop task which may engage the ventral ACC and orbitofrontal cortex (OFC). This might suggest the melancholic group showed a greater ventral ACC-OFC deficit than the nonmelancholic group, while both groups showed similar dorsal ACC-DLPFC deficit.

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Financial institutions are directly exposed to the credit risk, that is, the risk of the borrower not fulfill with their obligations, paying their debts in its stated periods established previously. The bank predict this type of risk, including them in their balance-sheets. In 2006/2007 there was the impact of a new financial crisis that spread around the world, known as the crisis of subprime. The objective of this study is to analyze if the provisions for credit risk or liquidation increased the sprouting of the crisis of subprime in ten major national banks, chosen accordant to their total assets. To answer this question, the balance-sheets of each one of these banks in the period of 2005 to 2007 were analyzed. This research is characterized, as for its objectives, as descriptive and as for the procedures as documentary research. It is also characterized as having a qualitative approach. The results show that the crisis of subprime has caused little impact in the credit risk provision of the analyzed institutions. It was noticed a slight increase in the provision indicators at the peak of the crisis in 2006. These percentages were reduced in, 2007, probably reflecting the economic stability of Brazil and the stagnation of the crisis Of subprime in that year, at least in relation to in our country.

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Objective: To assess from a health sector perspective the incremental cost-effectiveness of cognitive behavioural therapy (CBT) and selective serotonin reuptake inhibitors (SSRIs) for the treatment of major depressive disorder (MDD) in children and adolescents, compared to 'current practice'. Method: The health benefit is measured as a reduction in disability-adjusted life years (DALYs), based on effect size calculations from meta-analysis of randomised controlled trials. An assessment on second stage filter criteria ('equity'; 'strength of evidence', 'feasibility' and 'acceptability to stakeholders') is also undertaken to incorporate additional factors that impact on resource allocation decisions. Costs and benefits are tracked for the duration of a new episode of MDD arising in eligible children (age 6-17 years) in the Australian population in the year 2000. Simulation-modelling techniques are used to present a 95% uncertainty interval (UI) around the cost-effectiveness ratios. Results: Compared to current practice, CBT by public psychologists is the most cost-effective intervention for MDD in children and adolescents at A$9000 per DALY saved (95% UI A$3900 to A$24 000). SSRIs and CBT by other providers are less cost-effective but likely to be less than A$50 000 per DALY saved (> 80% chance). CBT is more effective than SSRIs in children and adolescents, resulting in a greater total health benefit (DALYs saved) than could be achieved with SSRIs. Issues that require attention for the CBT intervention include equity concerns, ensuring an adequate workforce, funding arrangements and acceptability to various stakeholders. Conclusions: Cognitive behavioural therapy provided by a public psychologist is the most effective and cost-effective option for the first-line treatment of MDD in children and adolescents. However, this option is not currently accessible by all patients and will require change in policy to allow more widespread uptake. It will also require 'start-up' costs and attention to ensuring an adequate workforce.

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This work concerns the influence of industrialized agriculture in the tropics on precipitation chemistry. A total of 264 rain events were sampled using a wet-only collector in central Sao Paulo State, Brazil, between January 2003 and July 2007. Electroneutrality balance calculations (considering H(+), K(+), Na(+), NH(4)(+), Ca(2)(+), Mg(2)(+), Cl(-), NO(3)(-), SO(4)(2-), F(-), PO(4)(3-), H(3)CCOO(-), HCOO(-), C(2)O(4)(2-) and HCO(3)(-)) showed that there was an excess of cations (similar to 15%), which was attributed to the presence of unmeasured organic anion species originating from biomass burning and biogenic emissions. On average, the three ions NH(4)(+), NO(3)(-) and H(+) were responsible for >55% of the total ion concentrations in the rainwater samples. Concentrations (except of H(+)) were significantly higher (t-test; P = 0.05), by between two to six-fold depending on species, during the winter sugar cane harvest period, due to the practice of pre-harvest burning of the crop. Principal component analysis showed that three components could explain 88% of the variance for measurements made throughout the year: PC1 (52%, biomass burning and soil dust resuspension); PC2 (26%, secondary aerosols); PC3 (10%, road transport emissions). Differences between harvest and non-harvest periods appeared to be mainly due to an increased relative importance of road transport/industrial emissions during the summer (non-harvest) period. The volume-weighted mean (VWM) concentrations of ammonium (23.4 mu mol L(-1)) and nitrate (17.5 mu mol L(-1)) in rainwater samples collected during the harvest period were similar to those found in rainwater from Sao Paulo city, which emphasizes the importance of including rural agro-industrial emissions in regional-scale atmospheric chemistry and transport models. Since there was evidence of a biomass burning source throughout the year, it appears that rainwater composition will continue to be affected by vegetation fires, even after sugar cane burning is phased out as envisaged by recent Sao Paulo State legislation. (C) 2011 Elsevier Ltd. All rights reserved.

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A 50-year-old woman presented with pancreatitis, fluctuant jaundice, weight loss, and abdominal pain. Contrast-enhanced computed tomography and abdominal ultrasound showed slight dilatation of the biliary tree and gallbladder without calculi. Endoscopy demonstrated a tumor protruding from the papilla of Vater. First endoscopically biopsy diagnosed no tumor, and a second biopsy diagnosed as papillary adenocarcinoma. The patient underwent duodenopancreatectomy. The specimen was fixed in formalin (10%). The tissue was processed routinely, and paraffin sections were stained with hematoxylin-eosin and periodic acid Schiff. Gross examination showed two tumors seen as prolapsed nodules growing isolated from the minor and major duodenal papillae measuring 1.5 and 1.0 cm, respectively, both covered by duodenal mucosa and the histologic study of both lesions demonstrated a moderately differentiated tubular adenocarcinoma, which invaded duodenal wall. After surgery, she is alive 24 months without evidence of recurrence.

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The class II major histocompatibility complex molecule I-A(g7) is strongly linked to the development of spontaneous insulin-dependent diabetes mellitus (IDDM) in non obese diabetic mice and to the induction of experimental allergic encephalomyelitis in Biozzi AB/H mice. Structurally, it resembles the HLA-DQ molecules associated with human IDDM, in having a non-Asp residue at position 57 in its beta chain. To identify the requirements for peptide binding to I-A(g7) and thereby potentially pathogenic T cell epitopes, we analyzed a known I-A(g7)-restricted T cell epitope, hen egg white lysozyme (HEL) amino acids 9-27. NH2- and COOH-terminal truncations demonstrated that the minimal epitope for activation of the T cell hybridoma 2D12.1 was M12-R21 and the minimum sequence for direct binding to purified I-A(g7) M12-Y20/K13-R21. Alanine (A) scanning revealed two primary anchors for binding at relative positions (p) 6 (L) and 9 (Y) in the HEL epitope. The critical role of both anchors was demonstrated by incorporating L and Y in poly(A) backbones at the same relative positions as in the HEL epitope. Well-tolerated, weakly tolerated, and nontolerated residues were identified by analyzing the binding of peptides containing multiple substitutions at individual positions. Optimally, p6 was a large, hydrophobic residue (L, I, V, M), whereas p9 was aromatic and hydrophobic (Y or F) or positively charged (K, R). Specific residues were not tolerated at these and some other positions. A motif for binding to I-A(g7) deduced from analysis of the model HEL epitope was present in 27/30 (90%) of peptides reported to be I-A(g7)-restricted T cell epitopes or eluted from I-A(g7). Scanning a set of overlapping peptides encompassing human proinsulin revealed the motif in 6/6 good binders (sensitivity = 100%) and 4/13 weak or non-binders (specificity = 70%). This motif should facilitate identification of autoantigenic epitopes relevant to the pathogenesis and immunotherapy of IDDM.

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A postal survey was conducted of all hospitals in Australia known to have a department of anaesthesia and an intensive care or high dependency unit. Each hospital was asked to report the anaesthetic and postoperative analgesic techniques used for the last ten cases of four common major surgical procedures-aorto-femoral bypass, repair of an abdominal aortic aneurysm, hemicolectomy and anterior resection of the rectum. Half of 76 hospitals sent a survey form completed and returned it. Responding hospitals were larger on average, than non-responding ones, but otherwise typical of them in terms of university affiliation and metropolitan versus rural location. For each of the procedures studied the proportion of cases in which epidural block was used intra- or postoperatively varied from 0% to 100%. Depending on the procedure, between 65% and 85% of hospitals used epidural block sometimes, with between 10% and 90% of patients in these hospitals being managed with this technique. There is wide variation in the use of epidural block, intra- and postoperatively, in Australia, variation that is unlikely to be explained by systematic differences between institutions in the patients seen or their suitability for one or other technique. This pattern of practice mirrors the lack of agreement about the proper place for epidural techniques evident in the recent literature. There is a widespread belief among clinicians that this is a question of great importance. Accordingly, we believe that anaesthetists and surgeons share an ethical responsibility to enter suitable patients in an appropriately designed randomized controlled trial in order to resolve this question.

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Purpose. To examine the postnatal development of major histocompatibility complex (MHC) class II-positive dendritic cells (DC) in the iris of the normal rat eye. Methods. Single-and double-color immunomorphologic studies were performed on whole mounts prepared from rat iris taken at selected postnatal ages (2 to 3 days to 78 weeks). Immunopositive cells were enumerated, using a quantitative light microscope, and MHC class II expression on individual cells was assessed by microdensitometric analysis. Results. Major histocompatibility class II-positive DCs in the iris developed in an age-dependent manner and reached adult-equivalent density and structure at approximately 10 weeks of age, considerably later than previously described in other DC populations in the rat. In contrast, the anti-rat DC monoclonal antibody OX62 revealed a population of cells present at adult-equivalent levels as early as 3 weeks after birth. Dual-color immunostaining and microdensitometric analysis demonstrated that during postnatal growth, development of the network of MHC class II-positive DCs was a consequence of the progressive increase in expression of MHC class II antigen by OX62-positive cells. Conclusions. During postnatal growth, the DC population of the iris develops initially as an OX62-positive-MHC class II-negative population, which then develops increasing MHC class II expression in situ and finally resembles classic DC populations in other tissue sites. Maturation of the iris DC population is temporally delayed compared with time to maturation in other tissue sites in the rat.

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Pentamidine is a second-line agent used in the treatment of leishmaniasis and its mode of action and mechanism of resistance is not well understood. It was previously demonstrated that transfection of promastigotes and amastigotes with the ABC transporter PRP1 gene confers resistance to pentamidine. To further clarify this point, we generated Leishmania amazonensis mutants resistant to pentamidine. Our results indicated that this ABC transporter is not associated with pentamidine resistance in lines generated by drug pressure through amplification or overexpression mechanisms of PRP1 gene. (C) 2008 Elsevier Inc. All rights reserved.

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PDI, a redox chaperone, is involved in host cell uptake of bacteria/viruses, phagosome formation, and vascular NADPH oxidase regulation. PDI involvement in phagocyte infection by parasites has been poorly explored. Here, we investigated the role of PDI in in vitro infection of J774 macrophages by amastigote and promastigote forms of the protozoan Leishmania chagasi and assessed whether PDI associates with the macrophage NADPH oxidase complex. Promastigote but not amastigote phagocytosis was inhibited significantly by macrophage incubation with thiol/PDI inhibitors DTNB, bacitracin, phenylarsine oxide, and neutralizing PDI antibody in a parasite redox-dependent way. Binding assays indicate that PDI preferentially mediates parasite internalization. Bref-A, an ER-Golgi-disrupting agent, prevented PDI concentration in an enriched macrophage membrane fraction and promoted a significant decrease in infection. Promastigote phagocytosis was increased further by macrophage overexpression of wild-type PDI and decreased upon transfection with an antisense PDI plasmid or PDI siRNA. At later stages of infection, PDI physically interacted with L. chagasi, as revealed by immunoprecipitation data. Promastigote uptake was inhibited consistently by macrophage preincubation with catalase. Additionally, loss-or gain-of-function experiments indicated that PMA-driven NADPH oxidase activation correlated directly with PDI expression levels. Close association between PDI and the p22phox NADPH oxidase subunit was shown by confocal colocalization and coimmunoprecipitation. These results provide evidence that PDI not only associates with phagocyte NADPH oxidase but also that PDI is crucial for efficient macrophage infection by L. chagasi. J. Leukoc. Biol. 86: 989-998; 2009.

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Objectives: Many morphometric magnetic resonance imaging (MRI) studies that have investigated the presence of gray matter (GM) volume abnormalities associated with the diagnosis of bipolar disorder (BD) have reported conflicting findings. None of these studies has compared patients with recent-onset psychotic BD with asymptomatic controls selected from exactly the same environment using epidemiological methods, or has directly contrasted BD patients against subjects with first-onset psychotic major depressive disorder (MDD). We examined structural brain differences between (i) BD (type I) subjects and MDD subjects with psychotic features in their first contact with the healthcare system in Brazil, and (ii) these two mood disorder groups relative to a sample of geographically matched asymptomatic controls. Methods: A total of 26 BD subjects, 20 subjects with MDD, and 94 healthy controls were examined using either of two identical MRI scanners and acquisition protocols. Diagnoses were based on DSM-IV criteria and confirmed one year after brain scanning. Image processing was conducted using voxel-based morphometry. Results: The BD group showed increased volume of the right dorsal anterior cingulate cortex relative to controls, while the MDD subjects exhibited bilateral foci GM deficits in the dorsolateral prefrontal cortex (p < 0.05, corrected for multiple comparisons). Direct comparison between BD and MDD patients showed a focus of GM reduction in the right-sided dorsolateral prefrontal cortex (p < 0.05, corrected for multiple comparisons) and a trend (p < 0.10, corrected) toward left-sided GM deficits in the dorsolateral prefrontal cortex of MDD patients. When analyses were repeated with scanner site as a confounding covariate the finding of increased right anterior cingulate volumes in BD patients relative to controls remained statistically significant (p = 0.01, corrected for multiple comparisons). Conclusions: These findings reinforce the view that there are important pathophysiological distinctions between BD and MDD, and indicate that subtle dorsal anterior cingulate abnormalities may be relevant to the pathophysiology of BD.

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Leishmaniasis is a parasitic disease caused by the intramacrophage protozoa Leishmania spp. and may be fatal if left untreated. Although pentavalent antimonials are toxic and their mechanism of action is unclear, they remain the first-line drugs for treatment of leishmaniasis. An effective therapy could be achieved by delivering antileishmanial drugs to the site of infection. Compared with free drugs, antileishmanial agent-containing liposomes are more effective, less toxic and have fewer adverse side effects. The aim of this study was to develop novel meglumine antimoniate (MA)-containing liposome formulations and to analyse their antileishmanial activity and uptake by macrophages. Determination of the 50% inhibitory concentration (IC(50)) values showed that MA-containing liposomes were >= 10-fold more effective than the free drug, with a 5-fold increase in selectivity index, higher activity and reduced macrophage toxicity. The concentration required to kill 100% of intracellular amastigotes was >= 40-fold lower when MA was encapsulated in liposomes containing phosphatidylserine compared with the free drug. Fluorescence microscopy analysis revealed increased uptake of fluorescent liposomes in infected macrophages after short incubation times compared with non-infected macrophages. In conclusion, these data suggest that MA encapsulated in liposome formulations is more effective against Leishmania-infected macrophages than the non-liposomal drug. Development of liposome formulations is a valuable approach to the treatment of infectious diseases involving the mononuclear phagocyte system. (C) 2011 Elsevier B.V. and the International Society of Chemotherapy. All rights reserved.

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Background: Structural and inflammatory changes in asthma involve both the large and small airways, with involvement of the distal lung being related to disease severity. We have previously shown that changes in the extracellular matrix (ECM) composition of the distal lung are associated with loss of alveolar attachments in patients with fatal asthma. However, major ECM elements, such as collagen I and fibronectin and their regulators, have not been addressed at the distal level. Objective: We sought to evaluate ECM remodeling in the distal lungs of asthmatic patients. Methods: Using immunohistochemistry and image analysis, we determined the content of collagen I and III, fibronectin, and matrix metalloproteinases; (MMPs) 1, 2, and 9 and tissue inhibitors of metalloproteinase (MMPs) 1 and 2 in the large and small airways and lung parenchyma of 24 patients with fatal asthma and compared the results with those of 11 nonasthmatic control subjects. Protein content was defined as the area of positive staining divided by basement membrane or septum length. Results: We observed increased collagen I and decreased collagen III content in the small airways of asthmatic patients compared with that seen in control subjects. Greater fibronectin and MMP-1, MMP-2, and MMP-9 content was observed at the outer area of the small airways in asthmatic patients. NIMP content was also increased in the peribronchiolar parenchyma in asthmatic patients. In contrast, TIMP expression was only increased in the large airways of asthmatic patients compared with that seen in control subjects. Conclusions: The outer area of the small airways is a major site of ECM remodeling in fatal asthma, potentially contributing to functional changes and the loss of airway-parenchyma interdependence observed in patients with fatal asthma. (J Allergy Clin Immunol 2009;123:1090-7.)

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Amphibian skin secretions are considered a rich source of biologically active compounds and are known to be rich in peptides, bufadienolides and alkaloids. Bufadienolides are cardioactive steroids from animals and plants that have also been reported to possess antimicrobial activities. Leishmaniasis and American Trypanosomiasis are parasitic diseases found in tropical and subtropical regions. The efforts toward the discovery of new treatments for these diseases have been largely neglected, despite the fact that the only available treatments are highly toxic drugs. In this work, we have isolated, through bioguided assays, the major antileishmanial compounds of the toad Rhinella jimi parotoid macrogland secretion. Mass spectrometry and (1)H and (13)C NMR spectroscopic analyses were able to demonstrate that the active molecules are telocinobufagin and hellebrigenin. Both steroids demonstrated activity against Leishmania (L.) chagasi promastigotes, but only hellebrigenin was active against Trypanosoma cruzi trypomastigotes. These steroids were active against the intracellular amastigotes of Leishmania, with no activation of nitric oxide production by macrophages. Neither cytotoxicity against mouse macrophages nor hemolytic activities were observed. The ultrastructural studies with promastigotes revealed the induction of mitochondrial damage and plasma membrane disturbances by telocinobufagin, resulting in cellular death. This novel biological effect of R. jimi steroids could be used as a template for the design of new therapeutics against Leishmaniasis and American Trypanosomiasis. (C) 2008 Elsevier Ltd. All rights reserved.