980 resultados para Objectives


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Objectives: The aim of this study was to diagnosis oral lesions related to HIV infection in individuals followed in the General Hospital of the School of Medicine of Ribeirao Preto, University of Sao Paulo, Brazil. The presence of oral lesions was correlated with gender, age, smoking habit, levels of CD4 lymphocytes, HIV load, time of HIV seropositivity, AIDS condition, use of removable dental prosthesis, and use of HAART. Materials and Methods: 340 HIV infected individuals were selected for this study, all participants of the study were examined by only one practiced dentist which performed anamnesis, peribuccal and oral examination. Results: Oral lesions were observed in 113 of 340 (33.2%) HIV infected individuals. These oral lesions included: oral candidiasis (17.7%) of pseudomembranous (10.8%) and of erythematous types (6.9%), angular cheilitis (13.9%), hairy leukoplakia (11.8%), and oral ulcers (2.1%). Oral candidiasis lesions were more frequently observed in women (p. 033). Smoking addict participants presented a high frequency of tongue hairy leukoplakia (p. 038) and a reduced frequency of oral ulcers (p. 018). Hairy leukoplakia and pseudomembranous candidiasis were inversely correlated to CD4+ L levels and directly correlated with HIV load, behaving as immune depression markers. Hairy leukoplakia and pseudomembranous candidiasis also showed an inverse correlation with HAART use (p < .0001). Patients using mobile dental prosthesis presented a high frequency of erythematous candidiasis (p. 003). Conclusion: The inverse correlation with CD4+ L level and the direct correlation with HIV load suggest that oral lesions could be used as alternative clinical markers for poor immune condition in HIV infected individuals.

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Objectives: To evaluate the sensitization to aeroallergens determined by skin prick test (SPT) in Brazilian adolescents, and to correlate its positivity with the diagnosis of asthma and/or rhinitis based on the written questionnaire (WQ) of ISAAC phase III study. Patients and Methods: A total of 996 adolescents (387 boys) were selected by systematic samples. A standard allergen extracts panel (positive/negative control, D pteronyssinus [Dpt], P americana [Pal, B germanica [Bg], dog, cat, fungal and grass mix) was used and its positivity compared with positive responses to asthma, rhinitis or both. Results: Positive SPT to at least one allergen was observed in 466 adolescents (46.8 %), with sensitisation to Dpt in 79.1 %. Positivity to more than one allergen occurred in 232 students (49.8 %). The frequency of positive SPTs was significantly higher among adolescents with asthma (OR = 2.16), rhinitis (OR = 1.69), and asthma and rhinitis (OR = 2.03). Positive SPT to four or more allergens were higher among asthmatics (OR = 2.6) and among adolescents with asthma and rhinitis (OR = 3). Conclusions: A high sensitisation rate to aeroallergens was observed, significantly higher among those with asthma, rhinitis or a combination of both, especially in multiple sensitisations.

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Objectives. In this study, we aimed to identify ancestry informative haplotypes and make interethnic admixture estimates using X-chromosome markers. Methods. A significant sample (461 individuals) of European, African, and Native American populations was analyzed, and four linkage groups were identified. The data obtained were used to describe the ancestral contribution of populations from four different geographical regions of Brazil (745 individuals). Results. The global interethnic admixture estimates of the four mixed populations under investigation were calculated applying all the 24 insertion/deletion (INDEL) markers. In the North region, a larger Native Americans ancestry was observed (42%). The Northeast and Southeast regions had smaller Native American contribution (27% in both of them). In the South region, there was a large European contribution (46%). Conclusions. The estimates obtained are compatible with expectations for a colonization model with biased admixture between European men (one X chromosome) and Native American and African women (two X chromosomes), so the 24 X-INDEL panel described here can be a useful to make admixture interethnic estimates in Brazilian populations. Am. J. Hum. Biol. 22:849-852,2010. (C) 2010 Wiley-Liss, Inc.

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P>Background The nonclassical human leucocyte antigen (HLA)-G molecule has been well recognized as a tolerogenic molecule and few studies have evaluated the role of the molecule in inflammatory cutaneous autoimmune diseases. Objectives To evaluate the expression of HLA-G in skin specimens of patients with psoriasis and to analyse its correlation with epidemiological and clinical variables. Methods Thirty untreated patients with psoriasis and 32 healthy individuals were enrolled. Immunohistochemistry was applied to identify HLA-G expression in formalin-fixed paraffin-embedded cutaneous skin biopsies. Results Soluble and membrane-bound HLA-G expression was detected in 30 (90%) of the skin specimens from patients presenting clinical and histopathological features of psoriasis. Although infiltrating lymphomononuclear cells of the dermis exhibited HLA-G expression, the epidermis was primarily targeted. HLA-G expression was also observed in 27% (three of 11) of the specimens that exhibited no clinical and histopathological features of psoriasis (nonaffected areas). In contrast, skin specimens obtained from healthy individuals exhibited no HLA-G expression (P < 0 center dot 0001). The intensity of HLA-G expression was not associated with type I/II psoriasis, Psoriasis Area and Severity Index score or clinical forms. Conclusions As the HLA-G molecule was consistently expressed in affected and, to a lesser extent, in nonaffected areas of untreated patients with psoriasis, irrespective of the severity of the clinical variants, one may hypothesize that the presence of HLA-G may be responsible, at least in part, for the regulation of autoimmune effector cells.

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Objectives Alterations in the enzymes involved in homocysteine (Hcy) metabolism or vitamin deficiency could play a role in coronary artery disease (CAD) development. This study investigated the influence of MTHFR and MTR gene polymorphisms, plasma folate and MMA on Hcy concentrations and CAD development. MMA and folate concentrations were also investigated according to the polymorphisms. Methods Two hundred and eighty-three unrelated Caucasian individuals undergoing coronary angiography (175 with CAD and 108 non-CAD) were assessed in a case-control study. Plasma Hcy and MMA were measured by liquid chromatography/tandem mass spectrometry. Plasma folate was measured by competitive immunoassay. Dietary intake was evaluated using a nutritional questionnaire. Polymorphisms MTHFR and MTR were investigated by polymerase chain reaction (PCR) followed by enzyme digestion or allele-specific PCR. Results Hcy mean concentrations were higher in CAD patients compared to controls, but below statistical significance (P = 0.246). Increased MMA mean concentrations were frequently observed in the CAD group (P = 0.048). Individuals with MMA concentrations > 0.5 mu mol/l (vitamin B(12) deficiency) were found only in the CAD group (P = 0.004). A positive correlation between MMA and Hcy mean concentrations was observed in both groups, CAD (P = 0.001) and non-CAD (P = 0.020). MMA mean concentrations were significantly higher in patients with hyperhomocysteinemia in both groups, CAD and non-CAD (P = 0.0063 and P = 0.013, respectively). Folate mean concentration was significantly lower in carriers of the wild-type MTHFR 1298AA genotype (P = 0.010). Conclusion Our results suggest a correlation between the MTHFR A1298C polymorphism and plasma folate concentration. Vitamin B(12) deficiency, reflected by increased MMA concentration, is an important risk factor for the development both of hyperhomocysteinemia and CAD.

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Rationale: The reduction of neutrophil migration to the bacterial focus is associated with poor outcome in sepsis. Objectives: The objective of this study was to identify soluble substances in the blood of septic mice that inhibit neutrophil migration. Methods: A pool of serum obtained from mice 2 hours after the induction of severe sepsis by cecal ligation and puncture inhibited the neutrophil migration. The proteins with inhibitory activity on neutrophil migration were isolated by Blue-Sepharose chromatography, high-performance liquid chromatography, and electrophoresis, and identified by mass spectrometry. Measurements and Main Results: Hemopexin was identified as the serum component responsible for the inhibition of neutrophil migration. In sepsis, the pretreatment of wild-type mice with hemopexin inhibited neutrophil migration to the focus of infection and decreased the survival rate from 87.5 to 50.0%. Hemopexin-null mice subjected to severe sepsis presented normal neutrophil migration, low bacteremia, and an improvement of 40% in survival rate. Moreover, hemopexin inhibited the neutrophil chemotaxis response evoked by C5a or macrophage inflammatory protein-2 and induced a reduction of CXCR2 and L-selectin as well as the up-regulation of CD11b expression in neutrophil membranes. The inhibitory effect of hemopexin on neutrophil chemotaxis was prevented by serine protease inhibitors or ATP. In addition, serum levels of ATP were decreased 2 hours after severe sepsis. Conclusions: These data demonstrate for the first time the inhibitory role of hemopexin in neutrophil migration during sepsis and suggest that the therapeutic inhibition of hemopexin or its protease activity could improve neutrophil migration to the focus of infection and survival in sepsis.

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Rationale Sepsis is defined as a systemic inflammatory response to infection, which in its severe form is associated with multiple organ dysfunction syndrome (MODS). The precise mechanisms by Which MODS develops remain unclear. Neutrophils have a pivotal role in the defense against infections; however, overwhelming activation of neutrophils is known to elicit tissue damage. Objectives: We investigated the role of the chemokine receptor CCR2 in driving neutrophil infiltration and eliciting tissue damage in remote organs during sepsis. Methods: Sepsis was induced in wild-type mice treated with CCR2 antagonist (RS504393) or CCR2(-/-) mice by cecal ligation and puncture (CLP) model. Neutrophil infiltration into the organs was measured by myeloperoxidase activity and fluorescence-activated cell sorter. CCR2 expression and chemotaxis were determined in neutrophils stimulated with Toll-like receptor agonists or isolated from septic mice and patients. Measurements and Main Results: CCR2 expression and responsiveness to its ligands was induced in circulating neutrophils during CLP-induced sepsis by a mechanism dependent on Toll-like receptor/nuclear factor-kappa B pathway. Genetic or pharmacologic inhibition of CCR2 protected mice from CLP-induced mortality. This protection was associated with lower infiltration of neutrophils into the lungs, heart, and kidneys and reduced serum biochemical indicators of organ injury and dysfunction. Importantly, neutrophils from septic patients express high levels of CCR2, and the severity of patient illness correlated positively with increasing neutrophil chemotaxis to CCR2 ligands. Conclusions: Collectively, these data identify CCR2 as a key receptor that drives the inappropriate infiltration of neutrophils into remote organs during sepsis. Therefore, CCR2 blockade is a novel potential therapeutic target for treatment of sepsis-induced MODS.

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Rationale Sepsis is a leading cause of death in the intensive care unit, characterized by a systemic inflammatory response (SIRS) and bacterial infection, which can often induce multiorgan damage and failure. Leukocyte recruitment, required to limit bacterial spread, depends on phosphoinositide-3 kinase gamma (PI3K gamma) signaling in vitro; however, the role of this enzyme in polymicrobial sepsis has remained unclear. Objectives: This study aimed to determine the specific role of the kinase activity of PI3K gamma in the pathogenesis of sepsis and multiorgan damage. Methods. PI3K gamma wild-type, knockout, and kinase-dead mice were exposed to cecal ligation and perforation induced sepsis and assessed for survival; pulmonary, hepatic, and cardiovascular damage; coagulation derangements; systemic inflammation; bacterial spread; and neutrophil recruitment. Additionally, wild-type mice were treated either before or after the onset of sepsis with a PI3K gamma inhibitor and assessed for survival, neutrophil recruitment, and bacterial spread. Measurements and Main Results: Both genetic and pharmaceutical PI3K gamma kinase inhibition significantly improved survival, reduced multiorgan damage, and limited bacterial decompartmentalization, while modestly affecting SIRS. Protection resulted from both neutrophil-independent mechanisms, involving improved cardiovascular function, and neutrophil-dependent mechanisms, through reduced susceptibility to neutrophil migration failure during severe sepsis by maintaining neutrophil surface expression of the chemokine receptor, CXCR2. Furthermore, PI3K gamma pharmacological inhibition significantly decreased mortality and improved neutrophil migration and bacterial control, even when administered during established septic shock. Conclusions: This study establishes PI3K gamma as a key molecule in the pathogenesis of septic infection and the transition from SIRS to organ damage and identifies it as a novel possible therapeutic target.

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Objectives Interleukin 33 (IL-33) is a new member of the IL-1 family of cytokines which signals via its receptor, ST2 (IL-33R), and has an important role in Th2 and mast cell responses. This study shows that IL-33 orchestrates neutrophil migration in arthritis. Methods and results Methylated bovine serum albumin (mBSA) challenge in the knee joint of mBSA-immunised mice induced local neutrophil migration accompanied by increased IL-33R and IL-33 mRNA expression. Cell migration was inhibited by systemic and local treatments with soluble (s) IL-33R, an IL-33 decoy receptor, and was not evident in IL-33R-deficient mice. IL-33 injection also induced IL-33R-dependent neutrophil migration. Antigen- and IL-33-induced neutrophil migration in the joint was dependent on CXCL1, CCL3, tumour necrosis factor a (TNF alpha) and IL-1 beta synthesis. Synovial tissue, macrophages and activated neutrophils expressed IL-33R. IL-33 induces neutrophil migration by activating macrophages to produce chemokines and cytokines and by directly acting on neutrophils. Importantly, neutrophils from patients with rheumatoid arthritis successfully treated with anti-TNF alpha antibody (infliximab) expressed significantly lower levels of IL-33R than patients treated with methotrexate alone. Only neutrophils from patients treated with methotrexate alone or from normal donors stimulated with TNF alpha responded to IL-33 in chemotaxis. Conclusions These results suggest that suppression of IL-33R expression in neutrophils, preventing IL-33-induced neutrophil migration, may be an important mechanism of anti-TNF alpha therapy of inflammation.

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Rationale Recovering the neutrophil migration to the infectious focus improves survival in severe sepsis. Recently, we demonstrated that the cystathionine gamma-lyase (CSE)/hydrogen sulfide (H(2)S) pathway increased neutrophil recruitment to inflammatory focus during sterile inflammation. Objectives: To evaluate if H(2)S administration increases neutrophil migration to infectious focus and survival of mice. Methods. Sepsis was induced by cecal ligation and puncture (CLP) Measurements and Main Results. The pretreatments of mice with H2S donors (NaHS or Lawesson`s reagent) improved leukocyte rolling/adhesion in the mesenteric microcirculation as well as neutrophil migration. Consequently, bacteremia levels were reduced, hypotension and lung lesions were prevented, and the survival rate increased from approximately 13% to approximately 80% Even when treatment was delayed (6 h after CLP), a highly significant reduction in mortality compared with untreated mice was observed Moreover, H(2)S pretreatment prevented the down-regulation of CXCR2 and L-selectin and the up-regulation of CD11b and G protein-coupled receptor kinase 2 in neutrophils during sepsis. H(2)S also prevented the reduction of intercellular adhesion molecule-1 expression in the endothelium of the mesenteric microcirculation in severe sepsis Confirming the critical role of H(2)S on sepsis outcome, pretreatment with dl-propargylglycine (a CSE inhibitor) inhibited neutrophil migration to the infectious focus, enhanced lung lesions, and induced high mortality in mice subjected to nonsevere sepsis (from 0 to similar to 80%). The beneficial effects of H(2)S were blocked by glibenclamide (a ATP-dependent K(+) channel blocker). Conclusions: These results showed that H(2)S restores neutrophil migration to the infectious focus and improves survival outcome in severe sepsis by an ATP-dependent K(+) channel-dependent mechanism.

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Rationale: Systemic administration of cannabidiol (CBD), a non-psychotomimetic component of Cannabis sativa, is able to attenuate cardiovascular and behavioral (freezing) changes induced by re-exposure to a context that had been previously paired with footshocks. The brain sites mediating this effect, however, remain unknown. The medial prefrontal cortex (mPFC) has been related to contextual fear conditioning. Objectives: (1) To verify, using c-Fos immunocytochemistry, if the mPFC is involved in the attenuation of contextual fear induced by systemic administration of CBD; (2) to investigate if direct microinjections of CBD into mPFC regions would also attenuate contextual fear. Results: Confirming previous results systemic administration of CBD (10 mg/kg) decreased contextual fear and associated c-Fos expression in the prefrontal cortex (prelimbic and infralimbic regions). The drug also attenuated c-Fos expression in the bed nucleus of the stria terminalis (BNST). Direct CBD (30 nmol) microinjection into the PL prefrontal cortex reduced freezing induced by re-exposure to the aversively conditioned context. In the infralimbic (IL) prefrontal cortex, however, CBD (30 nmol) produced an opposite result, increasing the expression of contextual fear conditioning. This result was confirmed by an additional experiment where the conditioning session was performed under a less aversive protocol. Conclusion: These results suggest that the PL prefrontal cortex may be involved in the attenuation of contextual fear induced by systemic injection of CBD. They also support the proposition that the IL and PL play opposite roles in fear conditioning. A possible involvement of the BNST in CBD effects needs to be further investigated. (C) 2009 Elsevier B.V. All rights reserved.

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Objectives The aim was to test the potential use of an extract of Mikania laevigata (popularly known in Brazil as guaco), made from leaves harvested in different months of the year, oil neutrophil migration after all inflammatory Stimulus and investigate the underlying molecular mechanisms. Methods We examined the effect of guaco on vascular permeability and leucocyte function in carrageenan-induced peritonitis in mice. Key findings Our results demonstrated that guaco extract administered subcutaneously (3 mg/kg) decreased the vascular permeability and also leucocyte rolling and adhesion to the inflamed tissues by a mechanism dependent on nitric oxide. Specifically, inhibitors of nitric oxide synthase remarkably abrogated the guaco extract-mediated suppression of neutrophil migration to the inflammatory site. In addition, guaco extract-mediated suppression of neutrophil migration appeared to be dependent on the production of the cytokines interleukin-1 beta and tumour necrosis factor-alpha. One of the major constituents of the guaco extract, coumarin, was able to inhibit the neutrophil migration towards the inflammatory focus. Conclusions In conclusion the anti-inflammatory effect induced by guaco extract may be by inhibition of pro-inflammatory cytokine production at the inflammatory site.

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Background/Objectives: Reduced food intake, appetite loss and alteration of ghrelin and PYY(3-36) secretion have been suggested to have a function in the loss of body weight commonly observed after gastrectomy. The objective of this study was to investigate the circulating concentrations of ghrelin and PYY(3-36) and their relationships with food intake, appetite and resting energy expenditure (REE) after gastrectomy plus vagotomy. Subjects/Methods: Seven patients with total gastrectomy (TG), 14 with partial gastrectomy (PG) and 10 healthy controls were studied. Habitual food intake and REE was assessed; fasting and postprandial plasma total ghrelin, PYY(3-36) concentrations and appetite ratings were determined after ingestion of a liquid test meal. Results: Differently from PG and controls, fasting ghrelin correlated with REE, and a higher energy intake was observed in the TG group. Fasting plasma ghrelin concentrations were lower in TG compared with controls, and no ghrelin response to the meal was observed in either PG or TG. Fasting plasma PYY(3-36) concentrations were not different among the groups. There was an early and exaggerated postprandial rise in PYY(3-36) levels in both PG and TG groups, but not in controls. No effect of ghrelin or PYY(3-36) concentrations was observed on hunger, prospective consumption or fullness ratings. Conclusions: Total ghrelin and PYY(3-36) do not seem to be involved with appetite or energy intake regulation after gastrectomy plus vagotomy. Ghrelin secreted by sources other than stomach is likely to have a function in the long-term regulation of body weight after TG. European Journal of Clinical Nutrition (2010) 64, 845-852; doi: 10.1038/ejcn.2010.88; published online 19 May 2010

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Tourism has had a profound impact upon destinations worldwide, and although this impact has been positive for many destinations, there are numerous examples where tourism has adversely impacted upon the environment and social fabric of the destination community (Coccossis 1996; Murphy 1985). The negative impacts of tourism have been attributed, among other things, to inadequate or non-existent planning for development (Gunn 1994; Hall2000). This has led to increased calls for tourism planning to offset some of the negative impacts that tourism can have on the destination community. While a number of approaches have been advocated, a collaborative philosophy, based on the principles of sustainability, is more likely to result in acceptable and successful policies and programmes for tourism destinations (Farrell1986; Jamal & Getz 1995; Maitland 2002; Minca & Getz 1995). Such an approach focuses on cooperation and broader based participation in tourism planning and decision-making between stakeholders to lead to agreement on planning directions and goals, with one of the primary objectives of collaborative arrangements being to develop a strategic vision for a destination (Bramwell & Lane 2000). [Extract from introduction]

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This paper focuses on the higher order factors affecting successful adoption of technologies. Drawing on the "actor-oriented perspective" in rural sociology, it is argued that successful examples of adoption at this higher level result from a complex conjunction of people and events, with outcomes that may have been quite unanticipated at the outset. From this perspective, research and extension projects and programs are viewed as arenas in which social actors–village leaders, farmers, researchers (local and international), aid officials, municipal agents, extension workers, and traders–pursue their own short- and long-term objectives and strategies. To this end, they maneuver, negotiate, organize, cooperate, participate, coerce, obstruct, form coalitions, adopt, adapt, and reject, all within a specific geographical and historical context.