978 resultados para coagulation necrosis


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Pro-inflammatory cytokines are believed to play an important role in the pathogenesis of dengue infection. This study reports cytokine levels in a total of 54 patients examined in Recife, State of Pernambuco, Brazil. Five out of eight patients who had hemorrhagic manifestations presented tumor necrosis factor-alpha (TNF-alpha) levels in sera which were statistically higher than those recorded for controls. In contrast, only one out of 16 patients with mild manifestations had elevated TNF-alpha levels. The levels of interleukin-6 (IL), IL-1beta tested in 24 samples and IL-12 in 30 samples were not significantly increased. Interferon-g was present in 10 out of 30 patients with dengue. The data support the concept that the increased level of TNF-alpha is related to the severity of the disease. Soluble TNF receptor p75 was found in most patients but it is unlikely to be related to severity since it was found with an equivalent frequency and levels in 15 patients with dengue fever and another 15 with dengue hemorrhagic fever.

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Tumor necrosis factor (TNF) alpha, interleukins (IL) 2, 4, 6, and 10, and IgG oligoclonal bands (IgG OB) in vitro production was assessed, after whole-blood stimulation with lipopolysaccharide or concanavalin A, in 61 patients presenting with relapsing-remitting, relapsing-progressive, or chronic progressive multiple sclerosis. Multiple sclerosis patients were receiving no treatment or azathioprine (AZA), cyclosporin, cyclophosphamide, subcutaneous interferon (IFN) beta 1 a, or corticosteroids (CST). Statistical correlations significantly showed that: (a) AZA lowers TNF-alpha (P = 0.002) and increases IL-4 production (P = 0.0024), and IFN-beta 1 a increases TNF-alpha and decreases IL-4 levels; (b) CST has a negative effect on TNF-alpha, IL-6, and IL-4 synthesis; and (c) AZA, IFN-beta 1 a, and CST diminish IgG OB synthesis (P = 0.001). Although our study of the dynamics of TNF-alpha, IL-2, IL-4, IL-6, and IL-10 in vitro production generally found no statistically significant correlations (partly explained by the limited number of values in the various groups), IL-6 was shown to drop during the periods surrounding relapse (P = 0.05) in the absence of treatment, while TNF-alpha (P = 0.04) and IL-6 (P < 0.05) dropped before exacerbation in the presence of AZA. In vitro production of TNF-alpha was closely and positively correlated with that of IL-6, independently of clinical features. The enhanced production of IL-10 detected before or at relapse with AZA and IFN-beta 1 a (trends) may interfere with initiation of the immune reaction and with the development of new CNS lesions. Some discrepancies with previously published results stress the difficulties in studying the state of stimulation of different populations of leukocytes by using a variety of in vitro stimuli and in establishing a correlation between mRNA studies and the amount of final or active protein produced.

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BACKGROUND: Activation of coagulation and fibrinolysis play a role in the pathophysiology of experimental arthritis. Objective: To determine the extent of activation of the coagulation and fibrinolytic pathways in different joint diseases in humans and to ascertain the factors that may influence fibrin deposition within the joint. METHODS: Plasma from normal subjects (controls, n= 21) and plasma and synovial fluid samples from patients with rheumatoid arthritis (RA; n = 64), osteoarthritis (OA; n = 29), spondyloarthropathy (SpA; n = 22) and crystal arthritis (CA; n = 25) were analyzed for the levels of TF (tissue factor) and tissue factor pathway inhibitor (TFPI) activities, thrombin-antithrombin III (TAT) complexes, and F1 + 2 (thrombin fragment), fibrin d-dimer and thrombin-activated fibrinolysis inhibitor (TAFI) antigenic levels. The measurements were analyzed by pairwise correlation with each other as well as with standard parameters of inflammation [C-reactive protein (CRP), joint leukocyte count]. Inter-group comparisons were performed to look for disease-specific differences. RESULTS: Compared with healthy controls, patients with joint diseases had higher levels of TAT, F1 + 2 and d-dimers in their plasma. In the synovial fluid, TF activity, TAT, d-dimers, and TAFI were significantly higher in inflammatory arthritides than in OA. The levels were highest in RA patients. In the plasma, TF activity was correlated with TAT and d-dimer levels with CRP, TFPI, and TAT. In the synovial fluid, TF activity correlated with plasma CRP levels, synovial fluid leukocyte count, and synovial TAT and TAFI levels. In addition, synovial d-dimers correlated with CRP, and synovial TAFI levels were correlated with synovial F1 + 2 and TAT. CONCLUSIONS: Activation of the coagulation and fibrinolytic cascades in the joint and in the circulation is evident in both inflammatory and degenerative joint diseases. Within the joint, inflammatory mechanisms leading to TF-mediated activation of the coagulation pathway and subsequent fibrin deposition is the most likely explanation for the observed findings. In the plasma, the link between inflammation (CRP increase) and TF activation is weak, and a non-TF-mediated mechanism of coagulation activation could explain these findings. RA is characterized by significantly higher levels of TAT in the synovial fluid and plasma than other arthritides. Although fibrinolytic activity is linked to inflammation, the increased amounts of TAFI in the joint, particularly in RA, may explain why fibrin formation is so prominent in this condition compared with other joint diseases.

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Hem fet un estudi retrospectiu de 73 adults amb pancreatitis aguda greu recollint variables analítiques i radiològiques a l'ingrés i a les 48h i relacionant-les amb l'existència de necrosi pancreàtica a la TC. Les variables relacionades amb la necrosi van ser: edat, leucòcits, VSG, TP, INR, glucèmia, urea, creatinina, proteïnes, albúmina, LDH, calci, PCR i presència de vessament pleural a la Rx. D'aquestes, el vessament pleural a l'ingrés i la hipoalbuminemia, les xifres altes de LDH i PCR a les 48 hores es van relacionar significativament, la qual cosa permet identificar pacients amb major risc en els quals instaurar mesures precoces

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We compared plasma tumor necrosis factor-alpha (TNF-alpha) levels among asymptomatic/"indeterminate" Chagas disease patients (ASY) and patients across the clinical spectrum of chronic Chagas disease cardiomyopathy (CCC). Idiopathic dilated cardiomyopathy (DCM) patients and normal controls (NC) were included as controls. ASY Chagas disease patients had significantly higher plasma TNF-alpha levels than NC. TNF-alpha levels among severe CCC patients with significant left ventricular (LV) dysfunction were similar to those of DCM patients, showing average 2-fold higher levels than CCC patients without LV dysfunction and ASY patients, and 8-fold higher levels than NC. In Chagas disease, chronic TNF-a production prior to heart failure may play a role in CCC progression.

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OBJECTIVE: To evaluate the initiation of and response to tumor necrosis factor (TNF) inhibitors for axial spondyloarthritis (axSpA) in private rheumatology practices versus academic centers. METHODS: We compared newly initiated TNF inhibition for axSpA in 363 patients enrolled in private practices with 100 patients recruited in 6 university hospitals within the Swiss Clinical Quality Management (SCQM) cohort. RESULTS: All patients had been treated with ≥ 1 nonsteroidal antiinflammatory drug and > 70% of patients had a baseline Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) ≥ 4 before anti-TNF agent initiation. The proportion of patients with nonradiographic axSpA (nr-axSpA) treated with TNF inhibitors was higher in hospitals versus private practices (30.4% vs 18.7%, p = 0.02). The burden of disease as assessed by patient-reported outcomes at baseline was slightly higher in the hospital setting. Mean levels (± SD) of the Ankylosing Spondylitis Disease Activity Score were, however, virtually identical in private practices and academic centers (3.4 ± 1.0 vs 3.4 ± 0.9, p = 0.68). An Assessment of SpondyloArthritis international Society (ASAS40) response at 1 year was reached for ankylosing spondylitis in 51.7% in private practices and 52.9% in university hospitals (p = 1.0) and for nr-axSpA in 27.5% versus 25.0%, respectively (p = 1.0). CONCLUSION: With the exception of a lower proportion of patients with nr-axSpA newly treated with anti-TNF agents in private practices in comparison to academic centers, adherence to ASAS treatment recommendations for TNF inhibition was equally high, and similar response rates to TNF blockers were achieved in both clinical settings.

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A major goal in the treatment of acute ischemia of a vascular territory is to restore blood flow to normal values, i.e. to "reperfuse" the ischemic vascular bed. However, reperfusion of ischemic tissues is associated with local and systemic leukocyte activation and trafficking, endothelial barrier dysfunction in postcapillary venules, enhanced production of inflammatory mediators and great lethality. This phenomenon has been referred to as "reperfusion injury" and several studies demonstrated that injury is dependent on neutrophil recruitment. Furthermore, ischemia and reperfusion injury is associated with the coordinated activation of a series of cytokines and adhesion molecules. Among the mediators of the inflammatory cascade released, TNF-alpha appears to play an essential role for the reperfusion-associated injury. On the other hand, the release of IL-10 modulates pro-inflammatory cytokine production and reperfusion-associated tissue injury. IL-1beta, PAF and bradykinin are mediators involved in ischemia and reperfusion injury by regulating the balance between TNF-alpha and IL-10 production. Strategies that enhance IL-10 and/or prevent TNF-alpha concentration may be useful as therapeutic adjuvants in the treatment of the tissue injury that follows ischemia and reperfusion.

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ABSTRACT: BACKGROUND: In acute myocardial infarction (AMI), both tissue necrosis and edema are present and both might be implicated in the development of intraventricular dyssynchrony. However, their relative contribution to transient dyssynchrony is not known. Cardiovascular magnetic resonance (CMR) can detect necrosis and edema with high spatial resolution and it can quantify dyssynchrony by tagging techniques. METHODS: Patients with a first AMI underwent percutaneous coronary interventions (PCI) of the infarct-related artery within 24 h of onset of chest pain. Within 5-7 days after the event and at 4 months, CMR was performed. The CMR protocol included the evaluation of intraventricular dyssynchrony by applying a novel 3D-tagging sequence to the left ventricle (LV) yielding the CURE index (circumferential uniformity ratio estimate; 1 = complete synchrony). On T2-weighted images, edema was measured as high-signal (>2 SD above remote tissue) along the LV mid-myocardial circumference on 3 short-axis images (% of circumference corresponding to the area-at-risk). In analogy, on late-gadolinium enhancement (LGE) images, necrosis was quantified manually as percentage of LV mid-myocardial circumference on 3 short-axis images. Necrosis was also quantified on LGE images covering the entire LV (expressed as %LV mass). Finally, salvaged myocardium was calculated as the area-at-risk minus necrosis (expressed as % of LV circumference). RESULTS: After successful PCI (n = 22, 2 female, mean age: 57 ± 12y), peak troponin T was 20 ± 36ug/l and the LV ejection fraction on CMR was 41 ± 8%. Necrosis mass was 30 ± 10% and CURE was 0.91 ± 0.05. Edema was measured as 58 ± 14% of the LV circumference. In the acute phase, the extent of edema correlated with dyssynchrony (r2 = -0.63, p < 0.01), while extent of necrosis showed borderline correlation (r2 = -0.19, p = 0.05). PCI resulted in salvaged myocardium of 27 ± 14%. LV dyssynchrony (=CURE) decreased at 4 months from 0.91 ± 0.05 to 0.94 ± 0.03 (p < 0.004, paired t-test). At 4 months, edema was absent and scar %LV slightly shrunk to 23.7 ± 10.0% (p < 0.002 vs baseline). Regression of LV dyssynchrony during the 4 months follow-up period was predicted by both, the extent of edema and its necrosis component in the acute phase. CONCLUSIONS: In the acute phase of infarction, LV dyssynchrony is closely related to the extent of edema, while necrosis is a poor predictor of acute LV dyssynchrony. Conversely, regression of intraventricular LV dyssynchrony during infarct healing is predicted by the extent of necrosis in the acute phase.

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Here we report the case of an immunocompetent 8-year-old child who developed acute retinal necrosis concomitant with a primary herpes simplex virus type I infection. Ocular inflammation changed along with the development of a specific antibody titer in the serum. This evidence suggests that the immune response of the host can significantly modulate the clinical aspect of the ocular infection.

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BACKGROUND: Acute retinal necrosis syndrome is clinically defined by the presence of peripheral necrotizing retinitis associated with severe occlusive vasculitis caused primarily by herpes simplex virus and varicella zoster virus. Previously considered as an exclusively retinal pathology, choroidal involvement, as demonstrated by indocyanine green angiography, has not been extensively studied. HISTORY AND SIGNS: Indocyanine green angiography was performed in 4 patients with ARN. Observed angiographic patterns included: 1. a characteristic triangular area of hypo-perfusion, 2. hypofluorescent lobular patches and areas of fuzzy choroidal vascular hyperfluorescence, and 3. isolated hypofluorescent lobular patches of the contralateral eye. THERAPY AND OUTCOME: Marked choroidal hypo-perfusion on indocyanine green angiography was associated with extensive retinal ischemia. Treatment included a combination of antiviral agents and corticosteroids complemented by prophylactic acetylsalicylate. CONCLUSION: Indocyanine green angiography may provide important information regarding choroidal vascular involvement in ARN. It may also permit the timely identification of sub-clinical contralateral eye involvement.

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Trimethyltin (TMT) is a neurotoxicant known to induce early microglial activation. The present study was undertaken to investigate the role played by these microglial cells in the TMT-induced neurotoxicity. The effects of TMT were investigated in monolayer cultures of isolated microglia or in neuron-enriched cultures and in neuron-microglia and astrocyte-microglia cocultures. The end points used were morphological criteria; evaluation of cell death and cell proliferation; and measurements of tumor necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6), and nitric oxide (NO) release in culture supernatant. The results showed that, in cultures of microglia, TMT (10(-6) M) caused, after a 5-day treatment, an increased release of TNF-alpha, without affecting microglial shape or cell viability. When microglia were cocultured with astrocytes, TNF-alpha release was decreased to undetectable levels. In contrast, in neuron-microglia cocultures, TNF-alpha levels were found to increase at lower concentrations of TMT (i.e., 10(-8) M). Moreover, at 10(-6) M of TMT, microglia displayed further morphological activation, as suggested by process retraction and by decrease in cell size. No morphological activation was observed in cultures of isolated microglial cells and in astrocyte-microglia cocultures. With regard to neurons, 10(-6) M of TMT induced about 30% of cell death, when applied to neuron-enriched cultures, whereas close to 100% of neuronal death was observed in neuron-microglia cocultures. In conclusion, whereas astrocytes may rather dampen the microglial activation by decreasing microglial TNF-alpha production, neuronal-microglial interactions lead to enhanced microglial activation. This microglial activation, in turn, exacerbates the neurotoxic effects of TMT. TNF-alpha may play a major role in such cell-cell communications.

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CONTEXT: Cirrhosis after viral hepatitis has been identified as a risk factor for osteoporosis in men. However, in postmenopausal women, most studies have evaluated the effect of primary biliary cirrhosis, but little is known about the effect of viral cirrhosis on bone mass [bone mineral density (BMD)] and bone metabolism. OBJECTIVE: Our objective was to assess the effect of viral cirrhosis on BMD and bone metabolism in postmenopausal women. DESIGN: We conducted a cross-sectional descriptive study. SETTING AND PATIENTS: We studied 84 postmenopausal female outpatients with viral cirrhosis and 96 healthy postmenopausal women from the general community. BMD was measured by dual-energy x-ray absorptiometry at lumbar spine (LS) and femoral neck (FN). RESULTS: The percentage with osteoporosis did not significantly differ between patients (LS, 43.1%; FN, 32.2%) and controls (LS, 41.2%; FN, 29.4%), and there was no difference in BMD (z-score) between groups. Serum concentrations of soluble TNF receptors, estradiol, and osteoprotegerin (OPG) were significantly higher in patients vs. controls (P < 0.001, P < 0.05, and P < 0.05, respectively). No significant difference was observed in urinary deoxypyridinoline. Serum OPG levels were positively correlated with soluble TNF receptors (r = 0.35; P < 0.02) and deoxypyridinoline (r = 0.37; P < 0.05). CONCLUSIONS: This study shows that bone mass and bone resorption rates do not differ between postmenopausal women with viral cirrhosis and healthy postmenopausal controls and suggests that viral cirrhosis does not appear to increase the risk of osteoporosis in these women. High serum estradiol and OPG concentrations may contribute to preventing the bone loss associated with viral cirrhosis in postmenopausal women.

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CONTEXT Adipose tissue hypoxia and endoplasmic reticulum (ER) stress may link the presence of chronic inflammation and macrophage infiltration in severely obese subjects. We previously reported the up-regulation of TNF-like weak inducer of apoptosis (TWEAK)/fibroblast growth factor-inducible 14 (Fn14) axis in adipose tissue of severely obese type 2 diabetic subjects. OBJECTIVES The objective of the study was to examine TWEAK and Fn14 adipose tissue expression in obesity, severe obesity, and type 2 diabetes in relation to hypoxia and ER stress. DESIGN In the obesity study, 19 lean, 28 overweight, and 15 obese nondiabetic subjects were studied. In the severe obesity study, 23 severely obese and 35 control subjects were studied. In the type 2 diabetes study, 11 type 2 diabetic and 36 control subjects were studied. The expression levels of the following genes were analyzed in paired samples of sc and visceral adipose tissue: Fn14, TWEAK, VISFATIN, HYOU1, FIAF, HIF-1a, VEGF, GLUT-1, GRP78, and XBP-1. The effect of hypoxia, inflammation, and ER stress on the expression of TWEAK and Fn14 was examined in human adipocyte and macrophage cell lines. RESULTS Up-regulation of TWEAK/Fn14 and hypoxia and ER stress surrogate gene expression was observed in sc and visceral adipose tissue only in our severely obese cohort. Hypoxia modulates TWEAK or Fn14 expression in neither adipocytes nor macrophages. On the contrary, inflammation up-regulated TWEAK in macrophages and Fn14 expression in adipocytes. Moreover, TWEAK had a proinflammatory effect in adipocytes mediated by the nuclear factor-kappaB and ERK but not JNK signaling pathways. CONCLUSIONS Our data suggest that TWEAK acts as a pro-inflammatory cytokine in the adipose tissue and that inflammation, but not hypoxia, may be behind its up-regulation in severe obesity.

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Overexpression of the tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) receptors, TRAIL-R1 and TRAIL-R2, induces apoptosis and activation of NF-kappaB in cultured cells. In this study, we have demonstrated differential signaling capacities by both receptors using either epitope-tagged soluble TRAIL (sTRAIL) or sTRAIL that was cross-linked with a monoclonal antibody. Interestingly, sTRAIL was sufficient for induction of apoptosis only in cell lines that were killed by agonistic TRAIL-R1- and TRAIL-R2-specific IgG preparations. Moreover, in these cell lines interleukin-6 secretion and NF-kappaB activation were induced by cross-linked or non-cross-linked anti-TRAIL, as well as by both receptor-specific IgGs. However, cross-linking of sTRAIL was required for induction of apoptosis in cell lines that only responded to the agonistic anti-TRAIL-R2-IgG. Interestingly, activation of c-Jun N-terminal kinase (JNK) was only observed in response to either cross-linked sTRAIL or anti-TRAIL-R2-IgG even in cell lines where both receptors were capable of signaling apoptosis and NF-kappaB activation. Taken together, our data suggest that TRAIL-R1 responds to either cross-linked or non-cross-linked sTRAIL which signals NF-kappaB activation and apoptosis, whereas TRAIL-R2 signals NF-kappaB activation, apoptosis, and JNK activation only in response to cross-linked TRAIL.

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BACKGROUND Renal ischemia/reperfusion (I/R) injury is manifested by acute renal failure (ARF) and acute tubular necrosis (ATN). The aim of this study was to evaluate the effectiveness of preconditioning with 3, 3, 5 triiodothyronine (T3) to prevent I/R renal injury. METHODOLOGY/PRINCIPAL FINDINGS THE RATS WERE DIVIDED INTO FOUR GROUPS: sham-operated, placebo-treated (SO-P), sham-operated T3- treated (SO- T3), I/R-injured placebo-treated (IR-P), and I/R-injured T3-treated (IR- T3) groups. At 24 h before ischemia, the animals received a single dose of T3 (100 μg/kg). Renal function and plasma, urinary, and tissue variables were studied at 4, 24, and 48 h of reperfusion, including biochemical, oxidative stress, and inflammation variables, PARP-1 immunohistochemical expression, and ATN morphology. In comparison to the SO groups, the IR-P groups had higher plasma urea and creatinine levels and greater proteinuria (at all reperfusion times) and also showed: increased oxidative stress-related plasma, urinary, and tissue variables; higher plasma levels of IL6 (proinflammatory cytokine); increased glomerular and tubular nuclear PARP-1 expression; and a greater degree of ATN. The IR-T3 group showed a marked reduction in all of these variables, especially at 48 h of reperfusion. No significant differences were observed between SO-P and SO-T3 groups. CONCLUSIONS This study demonstrates that preconditioning rats with a single dose of T3 improves the clinical signs and ATN of renal I/R injury. These beneficial effects are accompanied by reductions in oxidative stress, inflammation, and renal PARP-1 expression, indicating that this sequence of factors plays an important role in the ATN induced by I/R injury.