418 resultados para Pancreatitis -- immunology
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We have shown previously that nitric oxide (NO) controls platelet endothelial cell adhesion molecule (PECAM-1) expression on both neutrophils and endothelial cells under physiological conditions. Here, the molecular mechanism by which NO regulates lipopolysaccharide (LPS)-induced endothelial PECAM-1 expression and the role of interleukin (IL)-10 on this control was investigated. For this purpose, N-(G)-nitro-L-arginine methyl ester (L-NAME; 20 mg/kg/day for 14 days dissolved in drinking water) was used to inhibit both constitutive (cNOS) and inducible nitric oxide (iNOS) synthase activities in LPS-stimulated Wistar rats (5 mg/kg, intraperitoneally). This treatment resulted in reduced levels of serum NO. Under this condition, circulating levels of IL-10 was enhanced, secreted mainly by circulating lymphocytes, dependent on transcriptional activation, and endothelial PECAM-1 expression was reduced independently on reduced gene synthesis. The connection between NO, IL-10 and PECAM-1 expression was examined by incubating LPS-stimulated (1 mu g/ml) cultured endothelial cells obtained from naive rats with supernatant of LPS-stimulated lymphocytes, which were obtained from blood of control or L-NAME-treated rats. Supernatant of LPS-stimulated lymphocytes obtained from L-NAME-treated rats, which contained higher levels of IL-10, reduced LPS-induced PECAM-1 expression by endothelial cells, and this reduction was reversed by adding the anti-IL-10 monoclonal antibody. Therefore, an association between NO, IL-10 and PECAM-1 was found and may represent a novel mechanism by which NO controls endothelial cell functions.
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Aims: To evaluate the IL1RN polymorphism as a possible marker for Rheumatic Fever (RF) susceptibility or disease severity. Methods: The genotypes of 84 RF patients (Jones criteria) and 84 normal race-matched controls were determined through the analysis of the number of 86-bp tandem repeats in the second intron of IL1RN. The DNA was extracted from peripheral-blood leukocytes and amplified with specific primers. Clinical manifestations of RF were obtained through a standardized questionnaire and an extensive chart review. Carditis was defined as new onset cardiac murmur that was perceived by a trained physician with corresponding valvae regurgitation or stenosis on echocardiogram. Carditis was classified as severe in the presence of congestive heart failure or upon the indication for cardiac surgery. The statistical association among the genotypes, RF and its clinical variations was determined. Results: The presence of allele I and the genotype A1/A1 were found less frequently among patients with severe carditis when compared to patients without this manifestation (OR = 0.11, p = 0.031; OR = 0.092, p = 0.017). Neither allele I nor allele 2 were associated with the presence of RF (p = 0.188 and p = 0.106), overall carditis (p = 0.578 and p = 0.767), polyarthritis (p = 0.343 and p = 0.313) and chorea (p = 0.654 and p = 0.633). Conclusion: In the Brazilian population, the polymorphism of the IL-1ra gene is a relevant factor for rheumatic heart disease severity. (C) 2009 Elsevier Ltd. All rights reserved.
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Drug provocation tests (DPTs) are considered the gold standard for identifying adverse drug reactions (ADRs). The aim of this study was to analyze DPT results and discuss severe systemic reactions associated with them. This was a retrospective analysis of 500 patients with ADRs who sought treatment and were submitted to DPTs when indicated between 2006 and 2010. We performed DPTs according to the European Network for Drug Allergy recommendations. Single-blind, placebo-controlled DPTs were performed with antibiotics, local anesthetics, and nonsteroidal anti-inflammatory drugs, as well as with other drugs. Patient characteristics, DPT results, and reactions were analyzed. The sample comprised 198 patients (80.8% of whom were female patients) submitted to 243 DPTs. Ages ranged from 9 to 84 years (mean, 39.9 years). The 243 DPTs were performed with local anesthetics (n = 93), antibiotics (n = 19), acetaminophen (n = 44), benzydamine (n = 33), COX-2 inhibitors (n = 26), dipyrone (n = 7), aspirin (n = 4), or other drugs (n = 17). The results of 4 tests (1.6%) were inconclusive, whereas those of 10 (4.1%) revealed positive reactions to antibiotics (2/19), COX-2 inhibitors (2/26), acetaminophen (3/44), and local anesthetics (3/93). Two severe reactions were observed: cephalexin-induced anaphylactic shock and bupivacaine-induced anaphylaxis without shock. Four patients (2.0%) reacted to the placebo before administration of the drug. Drug provocation tests are safe for use in clinical practice but they should be placebo-controlled and should be performed under the supervision of an allergist. To confirm a presumptive diagnosis and to manage allergies appropriately, it is crucial to perform DPTs. (Allergy Asthma Proc 32:301-306, 2011; doi: 10.2500/aap.2011.32.3450)
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Rheumatic fever (RF) is an autoimmune disease caused by the gram-positive bacteria Streptococcus pyogenes that follows a nontreated throat infection in susceptible children. The disease manifests as polyarthritis, carditis, chorea, erythema marginatum, and/or subcutaneous nodules. Carditis, the most serious complication, occurs in 30% to 45% of RF patients and leads to chronic rheumatic heart disease (RHD), which is characterized by progressive and permanent valvular lesions. In this review, we will focus on the genes that confer susceptibility for developing the disease, as well as the innate and adaptive immune responses against S. pyogenes during the acute rheumatic fever episode that leads to RHD autoimmune reactions. The disease is genetically determined, and some human leukocyte antigen class II alleles are involved with susceptibility. Other single nucleotide polymorphisms for TNF-alpha and mannan-binding lectin genes were reported as associated with RF/RHD. T cells play an important role in RHD heart lesions. Several autoantigens were already identified, including cardiac myosin epitopes, vimentin, and other intracellular proteins. In the heart tissue, antigen-driven oligoclonal T cell expansions were probably the effectors of the rheumatic heart lesions. These cells are CD4(+) and produced inflammatory cytokines (TNF alpha and IFN gamma). Molecular mimicry is the mechanism that mediated the cross-reactions between streptococcal antigens and human proteins. The elucidation of chemokines and their receptors involved with the recruitment of Th1, Th2, and Th17 cells, as well as the function of T regulatory cells in situ will certainly contribute to the delineation of the real picture of the heart lesion process that leads to RHD.
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Introduction. Lung transplantation (LTx) candidates present incapacitating symptoms related to their mobility and activities of daily living, thereby affecting their work, social and emotional relations, and quality of life (QoL). Objective. To study the QoL of LTx candidates, seeking to identify domains that suffer the greatest impact and verify if there are differences among these impairments according to the original lung disease. Methods. We applied the Short Form-36 questionnaires and St George`s Respiratory Questionnaire (SGRQ). All data were analyzed by one-way analysis of variance and the Kruskal Wallis test for the probability with significance at P < 0.05. Results. Fifty patients were divided into groups of emphysema (n = 16), bronchiectasis (n = 12), idiopathic pulmonary fibrosis (n = 7), and cystic fibrosis (n = 15). The functional capacity, physical aspects, general status, and vitality domains showed average values below 50 points. The cystic fibrosis group showed higher functional capacity scores (46 +/- 23) than the emphysema (12 +/- 13) or idiopathic pulmonary fibrosis cohort (7 5). The limitation caused by pain affected the bronchiectasis more than the cystic fibrosis group (52 +/- 28 vs 81 +/- 25, respectively). The SGRQ scores showed impairment among all groups in all domains with average values over 50. The activities domain shows the highest score value; the emphysema (92 +/- 10) and idiopathic pulmonary fibrosis cohorts (91 +/- 9) were extremely affected compared with the cystic fibrosis (69 +/- 21) and bronchiectasis subjects (79 +/- 16). The impact domain show that subjects with cystic fibrosis were less emotionally affected by the disease. Conclusion. LTx candidates showed great impairment of their QoL due to their health problems, above all in the physical-functional aspects; the cystic fibrosis patients were the least affected by their health status.
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HLA-G is a non-classic Human Leukocyte Antigen (HLA-G) Class I of low polymorphism and restricted tissue distribution that displays tolerogenic functions. In heart transplantation and in combined liver/renal allograft transplantation, the expression of HLA-G has been associated with a lower incidence of acute graft rejection episodes and absence of chronic dysfunction. Since the expression of HLA-G in renal biopsies has been investigated only in few patients who received a combined kidney and liver transplant, in this study we performed a cross-sectional study, systematically comparing the expression of HLA-G in post-transplanted renal grafts, stratifying patients according to the presence or absence of rejection. Patients and Methods: Seventy-three renal specimens (10 with acute rejection and 13 with chronic allograft nephropathy, and 50 with no signs of rejection) were immunohistochemically evaluated for HLA-G expression. Results: In the group as a whole, HLA-G molecules were detected in 40 cases (54.8%). Among specimens that presented HLA-G expression, 2 out of 40 (5%) exhibited acute rejection, 2 (5%) exhibited chronic allograft nephropathy, and the remaining 36 (90%) exhibited no signs of rejection. The comparison between patients with rejection and those without rejection showed that the expression of HLA-G was significantly increased in specimens exhibiting no signs of rejection (p<0.0001). Considering only patients with acute rejection, 8 out of 10 patients showed no HLA-G expression in their kidney biopsies when compared to patients exhibiting no signs of rejection and absence of HLA-G was observed in 14 out of 50 (p=0.0032). Similarly, considering only patients with chronic allograft nephropathy, absence of HLA-G expression was observed in I I out of 13 specimens, whereas in patients without rejection absence of HLA-G was observed in 14 out of 50 (p=0.003). Therapy with tacrolimus was significantly associated with the expression of HLA-G and a better graft prognosis. Conclusions: Our results suggest that HLA-G expression in the kidney allograft and the use of tacrolimus are associated with a lower frequency of acute renal rejection and chronic allograft nephropathy. (c) 2007 Elsevier B.V. All rights reserved.
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The balance between different immunological stimuli is essential in the progression and stabilization of atherosclerotic plaques. Immune regulation has been suggested as potential target for the treatment of atherosclerotic disease. We sought to determine whether treatment with pentoxifylline, a phosphodiesterase inhibitor with immunomodulating properties, could reduce the pro-inflammatory response observed in patients with acute coronary syndromes (ACS) and increase anti-inflammatory activity. In a double-blind, prospective, placebo-controlled study, 64 patients with ACS were randomized to receive pentoxifylline 400 mg TID or placebo for 6 months. Analysis of the pro-inflammatory markers, Greactive protein (CRP), interleukin (IL)-6, IL-12, interferon-gamma and tumor necrosis factor (TNF)-alpha and the anti-inflammatory cytokines, transforming growth factor (TGF)-beta 1 and IL-10 were done at baseline, 1 and 6 months. Pentoxifylline treatment significantly reduced the adjusted levels of CRP and TNF-alpha compared to placebo after 6 months (P=0.04 and P < 0.01, respectively). IL-12 increase was significantly less pronounced with pentoxifylline (P=0.04). The levels of the anti-inflammatory cytokine, IL-10, also declined significantly less in the pentoxifylline group compared to placebo (P < 0.01) with a trend towards a higher increase of TGF-beta 1 in the former group (P=0.16). Pentoxifylline reduces pro-inflammatory and increases anti-inflammatory response in patients with ACS and may have beneficial clinical effects on cardiovascular events. (c) 2006 Elsevier Ireland Ltd. All rights reserved.
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Introduction. Chagas` disease is endemic in South America. Objective. This research reviewed the experience with cardiac transplantation in Chagas` disease, emphasizing reactivation, immunosuppression, and mortality. Methods. Over 25 years from March 1985 to March 2010, 107/409 (26.2%) patients with Chagas` disease underwent heart transplantation, patients including 74 (71.1%) men and 72 (67.2%), in functional class IV with 33 (30.8%) on vasopressors and 17 (10.7%) on mechanical circulatory support. Results. The diagnosis of disease reactivation was performed by identifying the parasite in the myocardium (n = 23; 71.8%) in the subcutaneous tissue (n = 8; 25.0%), in blood (n = 11; 34.3%), or in central nervous tissue (n = 1; 3.1%). Hospital mortality was 17.7% (n = 19) due to infection (n = 6; 31.5%), graft dysfunction (n = 6; 31.5%), rejection (n 4; 21.1%), or sudden death (n = 2; 10.5%). Late mortality was 27 (25.2%) cases, which were distributed as: rejection (n = 6; 22.2%), infection (n = 6; 22.2%), (n = lymphoma 4; 14.8%), sarcoma (n = 2; 7.4%), for constrictive pericarditis (n = 2; 7.4%) reactivation of Chagas` disease in the central nervous system (n = 1; 7.1%). Conclusions. Transplantation in Chagas` disease has peculiar problems that differ from other etiologies due to the possibility of disease reactivation and the increased possibility of emergence of cancers. However, transplantation is the only treatment able to modify the natural progression of the disease in its terminal phase. Early diagnosis and rapid introduction of benzonidazole reverses the histological patterns. Immunosuppression, especially steroids, predisposes to the development of cancer and disease reactivation.
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Introduction. Advantages of the bicaval versus the biatrial technique have been reported, emphasizing atrial electrical stability and less tricuspid regurgitation. Objective. To analyze the impact of the surgical technique on long-term pulmonary pressures, contractility, and graft valvular behavior after heart transplantation. Methods. Among 400 orthotopic heart transplantation recipients from 1985 to 2010, we selected 30 consecutive patients who had survived beyond 3 years. The biatrial versus bicaval surgical technique groups included 15 patients each. Their preoperative clinical characteristics were similar. None of the patients displayed a pulmonary vascular resistance or pulmonary artery pressure over 6U Wood or 60 mm Hg, respectively. We evaluated invasive hemodynamic parameters during routine endomyocardial biopsies. Two-dimensional echocardiographic parameters were obtained from routine examinations. Results. There were no significant differences regarding right atrial pressure, systolic pulmonary artery pressure, pulmonary capillary wedge pressure, pulmonary vascular resistance, cardiac index, systolic blood pressure, left ventricular ejection fraction, and mitral regurgitation (P > .05). Tricuspid regurgitation increased significantly over the 3 years of observation only among the biatrial group (P = .0212). In both groups, the right atrial pressure, pulmonary wedge capillary pressure, transpulmonary gradient, and pulmonary vascular resistance decreased significantly (P < .05) from the pre- to the postoperative examination. In both groups cardiac index and systemic blood pressure increased significantly after transplantation (P < .05). Comparative analysis of the groups only showed significant differences regarding right atrial pressure and degree of tricuspid regurgitation; the bicaval group showing the best performance. Conclusions. Both surgical techniques ensure adequate left ventricular function in the long term; however, the bicaval technique provided better trends in hemodynamic performance, as well as a lower incidence and severity of tricuspid valve dysfunction.
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Introduction. The quality and effectiveness of myocardial protection are fundamental problems to expand the use of and consequently good outcomes of donated hearts for transplantation. Objective. The purpose of this investigation was to compare the cardioprotective effects of Krebs-Henseleit, Bretschneider-HTK, St Thomas, and Celsior solutions using a modified nonrecirculating Langendorff column model of isolated perfused rat heart during prolonged cold storage. Materials and Methods. After removal 36 rat hearts underwent isolated perfusion into a Langendorff apparatus using Krebs-Henseleit solution for a 15-minute period of recovery; we excluded organs that did not maintain an aortic pressure above 100 m Hg. Subsequently, we equally distributed the hearts into four groups according to the cardioprotection solution; group 1, Krebs-Henseleit (control); group II, Bretschneider-HTK; group III, St Thomas; and group IV, Celsior. Each heart received the specific cardioplegic solution at 10 C for 2-hour storage at 20 C, before a 15 minutes perfusion with Krebs-Henseleit solution for recovery and stabilization. After 60 additional minutes of perfusion, every 5 minutes we determined heart rate (HR), coronary flow (CF), left ventricular systolic pressure (LVSP), and positive and negative peak of the first derivative of left ventricular pressure (+dP/dt and dP/dt, respectively). Results. Comparative analysis by Turkey`s test showed the following performances among the groups at 60 minutes of reperfusion: HR: II = IV > III > I; CF: II = IV > I = III; LVSP: IV > I = II = III; +dP/dt: IV > I = II = III; and dP/dt: IV = II > I = II. Conclusion. Cardioprotective solutions generally used in clinical practice are not able to avoid hemodynamic alterations in hearts exposed to prolonged ischemia. Celsior solution showed better performance than Bretschneider-HTK, St Thomas, and Krebs-Henseleit.
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Introduction. Lung tranplantation, a consolidated treatment for end-stage lung disease, utilizes preservation solutions, such as low potassium dextran (LPD), to mitigate ischemia reperfusion injury. We sought the local development of LPD solutions in an attempt to facilitate access and enhance usage. We also sought to evaluate the effectiveness of a locally manufactured LPD solution in a rat model of ex vivo lung perfusion. Methods. We randomized the following groups \?\adult of male Wistar rats (n = 25 each): Perfadex (LPD; Vitro life, Sweden); locally manufactured LPD-glucose (LPDnac) (Farmoterapica, Brazil), and normal saline solution (SAL) with 3 ischemic times (6, 12, and 24 hours). The harvested heart lung blocks were flushed with solution at 4 C. After storage, the blocks were connected to an IL-2 Isolated Perfused Rat or Guinea Pig Lung System (Harvard Apparatus) and reperfused with homologous blood for 60 minutes. Respiratory mechanics, pulmonary artery pressure, perfusate blood gas analysis, and lung weight were measured at 10-minute intervals. Comparisons between groups and among ischemic times were performed using analysis of variance with a 5% level of significance. Results. Lungs preserved for 24 hours were nonviable and therefore excluded from the analysis. Those preserved for 6 hours showed better ventilatory mechanics when compared with 12 hours. The oxygenation capacity was not different between lungs flushed with LPD or LPDnac, regardless of the ischemic time. SAL lungs showed higher PCO(2) values than the other solutions. Lung weight increased over time during perfusion; however, there were no significant differences among the tested solutions (LPD, P = .23; LPDnac, P = .41; SAL, P = .26). We concluded that the LPDnac solution results in gas exchange were comparable to the original LPD (Perfadex); however ventilatory mechanics and edema formation were better with LPD, particularly among lungs undergoing 6 hours of cold ischemia.
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Background. We assessed the results of a noninvasive therapeutic strategy on the long-term occurrence of cardiac events and death in a registry of patients with chronic kidney disease (CKD) and coronary artery disease (CAD). Methods. We analyzed 519 patients with CKD (56+/-9 years, 67% men, 67% whites) on maintenance hemodialysis with clinical or scintigraphic evidence of CAD by using coronary angiography. Results. In 230 (44%) patients, coronary angiography revealed significant CAD (lumen reduction >= 70%). Subjects with significant CAD were kept on medical treatment (MT; n=184) or referred for myocardial revascularization (percutaneous transluminal coronary angioplasty/coronary artery bypass graft-intervention; n=30) according to American College of Cardiology/American Heart Association guidelines. In addition, 16 subjects refused intervention and were also followed-up. Event-free survival for patients on MT at 12, 36, and 60 months was 86%, 71%, and 57%, whereas overall survival was 89%, 71%, and 50% in the same period, respectively. Patients who refused intervention had a significantly worse prognosis compared with those who actually underwent intervention (events: hazard ratio=4.50; % confidence interval=1.48-15.10; death: hazard ratio=3.39; % confidence interval 1.41-8.45). Conclusions. In patients with CKD and significant CAD, MT promotes adequate long-term event-free survival. However, failure to perform a coronary intervention when necessary results in an accentuated increased risk of events and death.
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Organ transplant shortage is a global problem caused by several factors, most of which are related to members of the family, who play it major role in the donation process. Objective. We sought to determine the most determinant features in the donor profile that relate to positive decisions versus refusal of donation. Material and Methods. Fifty-six families who were approached by the Organ Procurement Organization (OPO) from November 2004 to April 2006 agreed to participate in this work. To assess donor profiles, we used it structured interview. Results. Parental involvement directly in decisions about donation lead to significantly less frequent consent (P = .005), young donor age was associated with a reduced probability of donation (P = .002), violent death negatively influenced donation consent, excluding suicide (P = .004). Conclusion. The present study showed violent death, young patient age, and parental donation consent to be the most important factors that make it harder to obtain consent organ donation. When a collateral relative (sibling/uncle) or children were responsible for the donation decision, there was more success of consent.
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Extreme myocardial degeneration leading to advanced stages of cardiomyopathy with extensive atrophy is rarely observed before patients die. However, heterotopic transplantation is a special situation wherein this phenomenon can be observed. The greater part of the failed heart shows recuperation after receiving circulatory assistance by reduction of myocardial work. Herein we have reported an unusual behavior of degenerative cardiomyopathy associated with intense myocardial apoptosis resulting in extreme ventricular atrophy after heterotopic heart transplantation. An 11-year-old girl with end-stage heart failure due to dilated cardiomyopathy of undetermined etiology without pulmonary hypertension underwent heterotopic cardiac transplantation with an undersized (by weight mismatch) donor heart. After 9 years heart failure reappeared due to native heart enlargement leading to allograft compression. The patient underwent native heart replacement leaving her with 2 donor hearts. Despite normal hemodynamic recuperation, the patient experienced massive arterial microemboli which led to death. Pathological studies showed exuberant myocardial degeneration in the native heart with intense atrophy of the muscle and gigantic ventricular enlargement. The left ventricle wall was extremely thin with rarefaction of cardiomyocytes and replacement by fibrosis. The right ventricle showed old extensive thrombosis. In conclusion, this report is not usual as it is not frequent to observe cardiomyopathy with an intense degree of myocardial degeneration and atrophy, because the patient dies earlier. In special situations it is possible that a recipient may have 2 donor hearts with normal hemodynamics. Heterotopic heart transplantation is a surgical alternative in a priority situation offering excellent outcomes; however, the native heart must be removed when there is compromise of the function of the heterotopic allograft.
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Members of the nuclear factor of activated T cell (NFAT) family of transcription factors were originally described in T lymphocytes but later shown to be expressed in several immune and non-immune cell types. NFAT proteins can modulate cellular transformation intrinsically, and NFAT-deficient (NFAT1-/-) mice are indeed more susceptible to transformation than wild-type counterparts. However, the contribution of an NFAT1-/- microenvironment to tumor progression has not been studied. We have addressed this question by inoculating NFAT1-/- mice with B16F10 melanoma cells intravenously, an established model of tumor homing and growth. Surprisingly, NFAT1-/- animals sustained less tumor growth in the lungs after melanoma inoculation than wild-type counterparts. Even though melanoma cells equally colonize NFAT1-/- and wild-type lungs, tumors do not progress in the absence of NFAT1 expression. A massive mononuclear perivascular infiltrate and reduced expression of TGF-beta in the absence of NFAT1 suggested a role for tumor-infiltrating immune cells and the cytokine milieu. However, these processes are independent of an IL-4-induced regulatory tumor microenvironment, since lack of this cytokine does not alter the phenotype in NFAT1-/- animals. Bone marrow chimera experiments meant to differentiate the contributions of stromal and infiltrating cells to tumor progression demonstrated that NFAT1-induced susceptibility to pulmonary tumor growth depends on NFAT1-expressing parenchyma rather than on bone marrow-derived cells. These results suggest an important role for NFAT1 in radio-resistant tumor-associated parenchyma, which is independent of the anti-tumor immune response and Th1 versus Th2 cytokine milieu established by the cancer cells, but able to promote site-specific tumor growth.