Clinical relevance of nitrated beta 2-glycoprotein I in antiphospholipid syndrome: Implications for thrombosis risk

Β2-Glycoprotein I (β2GPI) is an important anti-thrombotic protein and is the major auto-antigen in the antiphospholipid syndrome (APS). The clinical relevance of nitrosative stress in post translational modification of β2GPI was examined.The effects of nitrated (n)β2GPI on its anti-thrombotic properties and its plasma levels in primary and secondary APS were determined with appropriate clinical control groups. β2-glycoprotein I was nitrated at tyrosines 218, 275 and 309. β2-glycoprotein I binds to lipid peroxidation modified products through Domains IV and V. Nitrated β2GPI loses this binding (p < 0.05) and had diminished activity in inhibiting platelet adhesion to vWF under high shear flow (p < 0.01). Levels of nβ2GPI were increased in patients with primary APS compared to patients with either secondary APS (p < 0.05), autoimmune disease without APS (p < 0.05) or non-autoimmune patients with arterial thrombosis (p < 0.01) and healthy individuals (p < 0.05).In conclusion tyrosine nitration of plasma β2GPI is demonstrated and has important implications with regards to the pathophysiology of platelet mediated thrombosis in APS. Elevated plasma levels of nβ2GPI in primary APS may be a risk factor for thrombosis warranting further investigation. © 2021 Elsevier Lt

Aspectos clínicos e radiográficos de caprino com megaesôfago

A seven month old female goat showed neck swelling, apathy, appetite and weight loss, restlessness, increased salivation, cough, and regurgitation episodes which occurred post feeding. The animal was evaluated through both clinical and radiographic examinations. Plain radiography was performed and contrasted X-ray was done using barium sulfate. For radiological examination, the lateral projection was used for analysis. The results showed a radiopaque content in the esophageal lumen dorsally positioned to heart with density and appearance similar to the rumen. A dilation of the esophagus was reported and a diagnosis of megaesophagus was made. In conclusion, contrast esophagography must be included in the diagnosis of megaesophagus in goats

Novel assays of thrombogenic pathogenicity in the antiphospholipid syndrome based on the detection of molecular oxidative modification of the major autoantigen β2-glycoprotein i

Objective Beta-2-glycoprotein I (β2GPI) constitutes the major autoantigen in the antiphospholipid syndrome (APS), a common acquired cause of arterial and venous thrombosis. We recently described the novel observation that β2GPI may exist in healthy individuals in a free thiol (biochemically reduced) form. The present study was undertaken to quantify the levels of total, reduced, and posttranslationally modified oxidized β2GPI in APS patients compared to various control groups. Methods In a retrospective multicenter analysis, the proportion of β2GPI with free thiols in serum from healthy volunteers was quantified. Assays for measurement of reduced as well as total circulating β2GPI were developed and tested in the following groups: APS (with thrombosis) (n = 139), autoimmune disease with or without persistent antiphospholipid antibodies (aPL) but without APS (n = 188), vascular thrombosis without APS or aPL (n = 38), and healthy volunteers (n = 91). Results Total β2GPI was significantly elevated in patients with APS (median 216.2 μg/ml [interquartile range 173.3-263.8]) as compared to healthy subjects (median 178.4 μg/ml [interquartile range 149.4-227.5] [P < 0.0002]) or control patients with autoimmune disease or vascular thrombosis (both P < 0.0001). The proportion of total β2GPI in an oxidized form (i.e., lacking free thiols) was significantly greater in the APS group than in each of the 3 control groups (all P < 0.0001). Conclusion This large retrospective multicenter study shows that posttranslational modification of β2GPI via thiol-exchange reactions is a highly specific phenomenon in the setting of APS thrombosis. Quantification of posttranslational modifications of β2GPI in conjunction with standard laboratory tests for APS may offer the potential to more accurately predict the risk of occurrence of a thrombotic event in the setting of APS. Copyright © 2011 by the American College of Rheumatology

Nucleation in tropical ecological restoration A nucleação na restauração ecológica de ecossistemas tropicais

Ecological theories of facilitation and nucleation are proposed as a basis for environmental restoration in tropical ecosystems. The main goal of this paper is to present restoration techniques based on the concept of nucleation, in which small nuclei of vegetation are established within a degraded land. The nucleation techniques (artificial shelters for animals, planting of herbaceous shrub life forms, soil and seed bank translocation, seed rain translocation, soil and seed rain translocation's seedling set, artificial perches, planting of native trees in groups, and ecological stepping-stones with functional groups) promote the landscape connectivity on two flows: inward: receiver connectivity and outward: donor connectivity. The nuclei development represents an alternative for restoration by prioritizing the natural processes of succession. This methodology appears to take long to generate vegetation corresponding to tropical climates, but is fundamental in the formation of communities capable of acting, in the future, as a new functional nuclei within the current fragmented landscape. This strategy also encourages greater integration between the theories and projects of ecological restoration for the development of human resources and to benefit the restoration practitioner.<br>As teorias ecológicas da facilitação e nucleação são propostas como base para a restauração ambiental de ecossistemas tropicais. Nesse "Ponto de Vista" apresentam-se técnicas de restauração fundamentadas no conceito de nucleação, onde pequenos núcleos de vegetação são implantados em uma área degradada. As técnicas de nucleação (abrigos artificiais para animais, plantio de espécies herbáceo-arbustivas, transposição de solo e banco de sementes, transposição de chuva de sementes, blocos de mudas procedentes de transposição de solo e chuva de sementes, poleiros artificiais, plantio de árvores nativas em grupos de Anderson, e trampolins ecológicos com grupos funcionais) promovem a conectividade da paisagem sob dois fluxos: interno: conectividade recebedora; e externo: conectividade doadora. O desenvolvimento dos núcleos representa uma alternativa de restauração que prioriza os processos de sucessão natural. A restauração através das técnicas de nucleação pode parecer muito lenta para atingir uma vegetação que corresponda ao clima tropical, porém representa uma base para a constituição de comunidades que, no futuro, poderão potencialmente atuar como novos núcleos funcionais dentro da atual paisagem fragmentada. Encoraja-se maior integração entre teorias ecológicas e projetos de restauração para desenvolvimento de recursos humanos e formação de restauradores ecológicos