266 resultados para non-accidental injury
Resumo:
Angiogenic T/natural killer (NK)-cell lymphoma is a non-Hodgkin lymphoma characterized by necrosis and vascular destruction that is strongly associated with Epstein-Barr virus and AIDS. Early diagnosis is essential to improve the chances of patient survival, but severe local inflammatory infiltrate impairs histologic diagnosis by obscuring neoplastic cells. The most common markers are CD2, CD56, cytoplasmic CD3, and CD43 EBV We describe 3 cases of angiogenic T/NK-cell lymphoma that show the diverse Presentation of the same disease. Patient I was HIV positive and had nasal obstruction, facial edema, and ulceration of the nasal mucosa. Patient 2 had fever, a sore throat, and weight loss. Patient 3 had facial edema, fever, proptosis, and rapid development Of neurologic alterations. Several biopsies were needed for histologic confirmation in these patients, despite positivity for the CD3 and CD56 markers.
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The genus Schistosoma is composed of blood flukes that infect vertebrates, from which three species are major causative agents of human schistosomiasis, a tropical disease that affects more than 200 million people. Current models of the recent evolution of Schistosoma indicate multiple events of migration and speciation from an Asian ancestral species. Transposable elements are important drivers of genome evolution and have been hypothesised to have an important role in speciation. In this work, we describe a comprehensive inventory of Schistosoma mansoni and Schistosoma japonicum retrotransposons, based on their recently published genomic data. We find a considerable difference in retrotransposon representation between the two species (22% and 13%, respectively). A large part of this difference can be attributed to higher representation of two previously described families of S. mansoni retrotransposons (SR2 and Perere-3/SR3), compared with the representation of their closest relative families in S. japonicum. A more detailed analysis suggests that these two S. mansoni families were the subject of recent bursts of transposition that were not paralleled by their S. japonicum counterparts. We hypothesise that these bursts could be a consequence of the evolutionary pressure resulting from migration of Schistosoma from Asia to Africa and their establishment in this new environment, helping both speciation and adaptation. (C) 2009 Australian Society for Parasitology Inc. Published by Elsevier Ltd. All rights reserved.
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Methionine-choline-deficient diet represents a model for the study of the pathogenesis of steatohepatitis. Male rats were divided into three groups, the first group receiving a control diet and the other two groups receiving a methionine-choline-deficient diet for 1 month (MCD1) and for 2 months (MCD2), respectively. The livers of the animals were collected for the determination of vitamin E, thiobarbituric acid reactive substances (TBARS), GSH concentration, DNA damages, and for histopathological evaluation. The hepatic TBARS and GSH content was higher (P < 0.05) in the groups receiving the experimental diet (MCD1 and MCD2) compared to control diet, and hepatic vitamin E concentration differed (P < 0.05) between the MCD1 and MCD2 groups, with the MCD2 group presenting a lower concentration. Damage to hepatocyte DNA was greater (P < 0.05) in the MCD2 group (262.80 DNA injuries/100 hepatocytes) compared to MCD1 (136.4 DNA injuries/100 hepatocytes) and control diet (115.83 DNA injuries/100 hepatocytes). Liver histopathological evaluation showed that steatosis, present in experimental groups was micro- and macro-vesicular and concentrated around the centrolobular vein, zone 3, with preservation of the portal space. The inflammatory infiltrate was predominantly periductal and the steatosis and inflammatory infiltrate was similar in the MCD1 and MCD2 groups, although the presence of Mallory bodies was greater in the MCD2 group. The study describes the contribution of a methionine-choline-deficient diet to the progression of steatosis, lipid peroxidation and hepatic DNA damage in rats, serving as a point of reflection about the role of these nutrients in the western diet and the elevated non-alcoholic steatohepatitis rates in humans.
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Microinjection of noradrenaline into the bed nucleus of the stria terminalis (BST) has been reported to cause a pressor response in unanesthetized rats, which was shown to be mediated by acute vasopressin release into the systemic circulation. In the present study we verified the involvement of magnocellular neurons of the hypothalamic paraventricular (PVN) or supraoptic (SON) nuclei and the local neurotransmitter involved in the pressor response to noradrenaline microinjection into the BST. The PVN pretreatment with the non-selective neurotransmission blocker CoCl(2) (1 nmol/100 nL) inhibited the noradrenaline-evoked pressor response. However, responses were not affected by SON treatment with CoCl(2). Further experiments were carried out to test if glutamatergic neurotransmission in the PVN mediates the pressor response evoked by noradrenaline microinjection into the BST. Pretreatment of the PVN with the selective N-methyl-d-aspartate (NMDA) receptor antagonist LY235959 (2 nmol/100 nL) did not affect the noradrenaline-evoked pressor response. However, PVN pretreatment with the selective non-NMDA receptor antagonist NBQX (2 nmol/100 nL) significantly reduced the pressor response to noradrenaline microinjection into the BST. In conclusion, our results suggest that pressor responses to noradrenaline microinjection into the BST are mediated by PVN magnocellular neurons without involvement of SON neurons. They also suggest that a glutamatergic neurotransmission through non-NMDA glutamate receptors in the PVN mediates the response.
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Ischemia and reperfusion injury (IRI) contributes to the development of chronic interstitial fibrosis/tubular atrophy in renal allograft patients, Cyclooxygenase (COX) 1 and 2 actively participate in acute ischemic injury by activating endothelial cells and inducing oxidative stress. Furthermore, blockade of COX I and 2 has been associated with organ improvement after ischemic damage. The aim of this study was to evaluate the role of COX I and 2 in the development of fibrosis by performing a COX I and 2 blockade immediately before IRI We subjected C57BI/6 male mice to 60 min of unilateral renal pedicle occlusion, Prior to surgery mice were either treated with indomethacin (IMT) at days -1 and 0 or were untreated. Blood and kidney samples were collected 6 wks after IRI. Kidney samples were analyzed by real-time reverse transcription-poly me rase chain reaction for expression of transforming growth factor beta (TGF-beta), monocyte chemoattractant protein 1 (MCP-1), osteopontin (OPN), tumor necrosis factor alpha (TNF-alpha), interleukin (IL)-1 beta, IL-10, heme oxygenose 1 (HO-1), vimentin, connective-tissue growth factor (CTGF), collagen 1, and bone morphogenic protein 7 (BMP-7), To assess tissue fibrosis we performed morphometric analyses and Sirius red staining. We also performed immunohistochemical analysis of anti-actin smooth muscle, Renal function did not significantly differ between groups. Animals pretreated with IMT showed significantly less interstitial fibrosis than nontreated animals. Gene transcript analyses showed decreased expression of TGF-beta, MCP-1,TNF-alpha, IL-1-beta, vimentin, collagen 1, CTGF and IL-10 mRNA (all P < 0.05), Moreover, HO-I mRNA was increased in animals pretreated with IMT (P < 0.05) Conversely, IMT treatment decreased osteopontin expression and enhanced BMP-7 expression, although these levels did rot reach statistical significance when compared with control expression levels, I he blockade of COX 1 and 2 resulted in less tissue fibrosis, which was associated with a decrease in proinflammatory cytokines and enhancement of the protective cellular response.
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The mechanism of isoproterenol-induced myocardial damage is unknown, but a mismatch of oxygen supply vs. demand following coronary hypotension and myocardial hyperactivity is the best explanation for the complex morphological alterations observed. Severe alterations in the structural integrity of the sarcolemma of cardiomyocytes have been demonstrated to be caused by isoproterenol. Taking into account that the sarcolemmal integrity is stabilized by the dystrophin-glycoprotein complex (DGC) that connects actin and laminin in contractile machinery and extracellular matrix and by integrins, this study tests the hypothesis that isoproterenol affects sarcolemmal stability through changes in the DGC and integrins. We found different sensitivity of the DGC and integrin to isoproterenol subcutaneous administration. Immunofluorescent staining revealed that dystrophin is the most sensitive among the structures connecting the actin in the cardiomyocyte cytoskeleton and the extracellular matrix. The sarcomeric actin dissolution occurred after the reduction or loss of dystrophin. Subsequently, after lysis of myofilaments, gamma-sarcoglycan, beta-dystroglycan, beta 1-integrin, and laminin alpha-2 expressions were reduced followed by their breakdown, as epiphenomena of the myocytolytic process. In conclusion, administration of isoproterenol to rats results in primary loss of dystrophin, the most sensitive among the structural proteins that form the DGC that connects the extracellular matrix and the cytoskeleton in cardiomyocyte. These changes, related to ischaemic injury, explain the severe alterations in the structural integrity of the sarcolemma of cardiomyocytes and hence severe and irreversible injury induced by isoproterenol.
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T cell activation is a complex process involving many steps and the role played by the non-protein-coding RNAs (ncRNAs) in this phenomenon is still unclear. The non-coding T cells transcript (NTT) is differentially expressed during human T cells activation, but its function is unknown. Here, we detected a 426 m NTT transcript by RT-PCR using RNA of human lymphocytes activated with a synthetic peptide of HIV-1. After cloning, the sense and antisense 426 nt NTT transcripts were obtained by in vitro transcription and were sequenced. We found that both transcripts are highly structured and are able to activate PKR. A striking observation was that the antisense 426 nt NTT transcript is significantly more effective in activating PKR than the corresponding sense transcript. The transcription factor NF-kappa B is activated by PKR through phosphorylation and subsequent degradation of its inhibitor I-kappa B beta. We also found that the antisense 426 nt NTT transcript induces more efficiently the degradation Of I-kappa B beta than the sense transcript. Thus, this study suggests that the role played by NTT in the activation of lymphocytes can be mediated by PKR through NF-kappa B activation. However, the physiological significance of the activity of the antisense 426 nt NTT transcript remains unknown. (c) 2007 Elsevier Inc. All rights reserved.
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While endogenous nitric oxide (NO) may be relevant to the beneficial hemodynamic effects produced by sildenafil during acute pulmonary embolism (APE), huge amounts of inducible NO synthase (iNOS)derived NO may contribute to lung injury. We hypothesized that iNOS inhibition with S-methylisothiourea could attenuate APE-induced increases in oxidative stress and pulmonary hypertension and, therefore, could improve the beneficial hemodynamic and antioxidant effects produced by sildenafil during APE. Hemodynamic evaluations were performed in non-embolized dogs treated with saline (n = 4), S-methylisothiourea (0.01 mg/kg followed by 0.5 mg/kg/h, n = 4), sildenafil (0.3 mg/kg, n = 4), or S-methylisothiourea followed by sildenafil (n = 4), and in dogs that received the same drugs and were embolized with silicon microspheres (n = 8 for each group). Plasma nitrite/nitrate (NOx) and thiobarbituric acid reactive substances (TBARS) concentrations were determined by Griess and a fluorometric assay, respectively. APE increased mean pulmonary arterial pressure (MPAP) and pulmonary vascular resistance index (PVRI) by 25 +/- 1.7 mm Hg and by 941 +/- 34 dyn s cm(-5) m(-2), respectively. S-methylisothiourea neither attenuated APE-induced pulmonary hypertension, nor enhanced the beneficial hemodynamic effects produced by sildenafil after APE (>50% reduction in pulmonary vascular resistance). While sildenafil produced no change in plasma NOx concentrations, S-methylisothiourea alone or combined with sildenafil blunted APE-induced increases in NOx concentrations. Both drugs, either alone or combined, produced antioxidant effects. In conclusion, although iNOS-derived NO may play a key role in APE-induced oxidative stress, our results suggest that the iNOS inhibitor S-methylisothiourea neither attenuates APE-induced pulmonary hypertension, nor enhances the beneficial hemodynamic effects produced by sildenafil. (C) 2010 Elsevier Inc. All rights reserved.
Resumo:
Gene expression of peripheral tissue antigens (PTAs) in stromal medullary thymic epithelial cells (mTECs) is a key process to the negative selection of autoreactive thymocytes. This phenomenon was termed ""promiscuous gene expression"" (PGE), which is partially controlled by the Aire gene. Nevertheless, reasons for the correlation of Aire and PTAs with the emergence of autoimmune diseases are largely unknown, though it may be a result of a chronological effect. Although the effect of Aire mutations in pathogenic autoimmunity is well know, it could not be a unique cause for autoimmunity. Independently of mutations, temporal deregulation of Aire expression may imbalance Aire-dependent PTAs and/or wide PGE. This deregulation may be an early warning sign for autoimmune diseases as it guarantees autoantigen representation in the thymus. To assess this hypothesis, we studied the expression levels of Aire, Aire-dependent (Ins2) and Aire-independent (Gad67 and Col2a1) PTAs using real-time-PCR of the thymic stromal cells of NOD mice during the development of autoimmune type 1 diabetes mellitus (DM-1). Wide PGE was studied by microarrays in which the PTA genes were identified through parallel CD80(+) mTEC 3.10 cell line expression profiling. The results show that Aire gene was down-regulated in young pre-autoimmune (pre-diabetic) NOD mice. PGE and specific PTA genes were down-regulated in adult autoimmune diabetic animals. These findings represent evidence indicating that chronological deregulation of genes important to negative selection may be associated with the development of an autoimmune disease (DM-1) in mice.
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Cytogenetic information of non-ossifying fibromas (NOFs) is exceptionally limited. This fact relies, in part, on their benign nature but mainly because most cases evolve undetected or there is no need for surgical intervention. We report the case of a NOF arising in the left tibia of a 14-year-old male with an invariable clonal translocation. The karyotype was denoted as 42-46,XY,t(11;3;14)(q23;p21;p11). There are only two previous reported cases of clonally aberrant NOF. Records from additional cases will be essential to assess whether consistent karyotypic aberrations define this lesion. Pediatr Blood Cancer 2010;54:764 767. (C) 2010 Wiley-Liss, Inc.
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Common features such as elastic fibre destruction, mucoid accumulation, and smooth muscle cell apoptosis are co-localized in aneurysms of the ascending aorta of various aetiologies. Recent experimental studies reported an activation of TGF-beta in aneurysms related to Marfan (and Loeys-Dietz) syndrome. Here we investigate TGF-beta signalling in normal and pathological human ascending aortic wall in syndromic and non-syndromic aneurysmal disease. Aneurysmal ascending aortic specimens, classified according to aetiology: syndromic MFS (n = 15, including two mutations in TGFBR2), associated with BAV (n = 15) or degenerative forms (n = 19), were examined. We show that the amounts of TGF-beta 1 protein retained within and released by aneurysmal tissue were greater than for control aortic tissue, whatever the aetiology, contrasting with an unchanged TGF-beta 1 mRNA level. The increase in stored TGF-beta 1 was associated with enhanced LTBP-I protein and mRNA levels. These dysiregulations of the extracellular ligand are associated with higher phosphorylated Smad2 and Smad2 mRNA levels in the ascending aortic wall from all types of aneurysm. This activation correlated with the degree of elastic fibre fragmentation. Surprisingly, there was no consistent association between the nuclear location of pSmad2 and extracellular TGF-beta 1 and LTBP-I staining and between their respective mRNA expressions. In parallel, decorin. was focally increased in aneurysmal media, whereas biglycan was globally decreased in aneurysmal aortas. In conclusion, this study highlights independent dysregulations of TGF-beta retention and Smad2 signalling in syndromic and non-syndromic aneurysms of the ascending aorta. Copyright (C) 2009 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
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This study evaluated the arterial response to cobalt-chromium stents with and without polymer coating (Camouflage (R), Hemoteq AG, Wuerselen, Germany) implanted in pigs. Cobalt-chromium balloon-expandable stents (4 x 16 mm) were implanted in the common carotid arteries of nine pigs. Histological analysis of endothelialization, inflammation and injury was performed one month later. All stents were successfully deployed, and all but one animal survived the 30 study days. All arteries were patent. Endothelialization was nearly complete in most sections of all carotid stents in both groups. There were mild inflammatory infiltrate and mild-to-moderate injury, which were associated with the stent shafts and not significantly different between groups. Our findings suggest that, in porcine carotid arteries, the histological response to balloon-expandable cobalt-chromium stents coated with polymer (Camouflage (R), Hemoteq AG) is similar to the response to non-coated cobalt-chromium stents.
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Positive end-expiratory pressure (PEEP) and sustained inspiratory insufflations (SI) during acute lung injury (ALI) are suggested to improve oxygenation and respiratory mechanics. We aimed to investigate the hemodynamic effects of PEEP with and without alveolar recruiting maneuver in a mild ALI model induced by inhalation of hydrochloric acid. Thirty-two pigs were randomly allocated into four groups (Control-PEEP, Control-SI, ALI-PEEP and ALI-SI). ALI was induced by intratracheal instillation of hydrochloric acid. PEEP values were progressively increased and decreased from 5, 10, 15 and 20 cmH(2)O in all groups. Three SIs maneuvers of 30 cmH(2)O for 20 s were applied to the assignable groups between each PEEP level. Transesophageal echocardiography (TEE), global hemodynamics, oxygenation indexes and gastric tonometry were measured 5 min after the maneuvers had been concluded and at each established value of PEEP (5, 10, 15 and 20 cmH(2)O). The cardiac index, ejection fraction and end-diastolic volume of right ventricle were significantly (P < 0.001) decreased with PEEP in both Control and ALI groups. Left ventricle echocardiography showed a significant decrease in end-diastolic volume at 20 cmH(2)O of PEEP (P < 0.001). SIs did not exert any significant hemodynamic effects either early (after 5 min) or late (after 3 h). In a mild ALI model induced by inhalation of hydrochloric acid, significant hemodynamic impairment characterized by cardiac function deterioration occurred during PEEP increment, but SI, probably due to low applied values (30 cmH(2)O), did not exert further negative hemodynamic effects. PEEP should be used cautiously in ALI caused by acid gastric content inhalation.
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Santos, K.B.; Daniel, A.G.T. & Hagiwara, M.K. [Reduced erythrocitary Glutathione and Heinz bodies in cats experimentally infected with the Feline Immunodeficiency Virus.] Glutationa Reduzida Eritrocitaria e Corpusculos de Heinz em gatos infectados experimentalmente pelo Virus da Imunodeficieneia Felina. Revista Brasileira de Medicina Veterinaria, 30(1):26-30, 2008. Centro Universitario Serra dos Orgaos, Rua Comendador Queiroz 52, Apto. 1403, Niteroi, RJ 24230-220, Brasil. E-mail: keilabsantos@)gmail.com The Feline Immunodeficiency Virus (FIV) produces a chronic infection with immunologic system disfunctions in domestic cats developing non-responsive anaemia. The feline immunologic status depression produces free radicals, whose imbalance between production and removal in the organism favour the oxidative injury occurrence. Heinz bodies in large amounts also can evident in vivo oxidative damage. Glutatione, a tripeptide found in the animal cells, is an important protection mechanism against oxidative damages. In this work erythrocyte reduced glutathione (GSH) concentrations for healthy and cats experimentally infected by FIV were determinated in relation to the hemogram and the Heinz bodies presence. All of the animals presents normal values for hemogram and Heinz bodies, however the GSH erythrocyte concentrations in the FIV positive cats were below the normality probably due to an passive depletion to GSH.
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This study was undertaken to test whether the structural remodelling of pulmonary parenchyma can be sequentially altered in a model and method that demonstrate the progression of the disease and result in remodelling within the lungs that is typical of idiopathic pulmonary fibrosis. Three groups of mice were studied: (i) animals that received 3-5-di-tert-butyl-4-hydroxytoluene (BHT) and were killed after 2 weeks (early BHT = 9); (ii) animals that received BHT and were killed after 4 weeks (late BHT = 11); (iii) animals that received corn oil solution (control = 10). The mice were placed in a ventilated Plexiglas chamber with a mixture of pure humidified oxygen and compressed air. Lung histological sections underwent haematoxylin-eosin, immunohistochemistry (epithelial, endothelial and immune cells) and specific staining (collagen/elastic fibres) methods for morphometric analysis. When compared with the control group, early BHT and late BHT groups showed significant decrease of type II pneumocytes, lower vascular density in both and higher endothelial activity. CD4 was increased in late BHT compared with early and control groups, while CD8, macrophage and neutrophil cells were more prominent only in early BHT. The collagenous fibre density were significantly higher only in late BHT, whereas elastic fibre content in late BHT was lower than that in control group. We conclude that the BHT experimental model is pathologically very similar to human usual interstitial pneumonia. This feature is important in the identification of animal models of idiopathic pulmonary fibrosis that can accurately reflect the pathogenesis and progression of the human disease.