Reversal of the anticoagulant and anti-hemostatic effect of low molecular weight heparin by direct prothrombin activation

Lopap, found in the bristles of Lonomia obliqua caterpillar, is the first exogenous prothrombin activator that shows serine protease-like activity, independent of prothrombinase components and unique lipocalin reported to interfere with hemostasis mechanisms. To assess the action of an exogenous prothrombin activator reversing the anticoagulant and antihemostatic effect induced by low molecular weight heparin (LMWH), male New Zealand rabbits (N = 20, weighing 3.8-4.0 kg) allocated to 4 groups were anticoagulated with 1800 IU/kg LMWH (iv) over 2 min, followed by iv administration of saline (SG) or recombinant Lopap (rLopap) at 1 µg/kg (LG1) or 10 µg/kg (LG10), 10 min after the injection of LMWH, in a blind manner. Control animals (CG) were treated only with saline. The action of rLopap was assessed in terms of activated partial thromboplastin time (aPTT), prothrombin fragment F1+2, fibrinogen, and ear puncture bleeding time (BT) at 5, 10, 15, 17, 20, 30, 40, 60, and 90 min after initiation of LMWH infusion. LG10 animals showed a decrease of aPTT in more than 50% and BT near to normal baseline. The level of prothrombin fragment F1+2 measured by ELISA had a 6-fold increase with rLopap treatment (10 µg/kg) and was inversely proportional to BT in LMWH-treated animals. Thus, Lopap, obtained in recombinant form using E. coli expression system, was useful in antagonizing the effect of LMWH through direct prothrombin activation, which can be a possible strategy for the reversal of bleeding and anticoagulant events

Influência do óleo de linhaça sobre o desempenho e a qualidade dos ovos de poedeiras semipesadas Influence of linseed oil on performance and egg quality of semi-heavy laying hens

O experimento foi conduzido para avaliar a influência da adição de óleo de linhaça em substituição ao óleo de soja em rações para poedeiras semipesadas sobre o desempenho e a qualidade interna e externa dos ovos. Utilizaram-se 192 poedeiras da linhagem Bovans Godline com 29 semanas de idade, distribuídas em seis tratamentos, que consistiram de uma dieta controle (sem óleo vegetal) e de cinco dietas contendo 0,0; 0,5; 1,0; 1,5 e 2,0% de óleo de linhaça em substituição, respectivamente, a 100, 75, 50, 25 ou 0% do óleo de soja. Avaliaram-se a produção (PROD), o peso (PO) e a massa de ovo (MO), as conversões por massa (CMO) e por dúzia de ovos (CDZ), os pesos e as porcentagens de albúmen, gema e casca, a gravidade específica, os teores de matéria seca, cinzas e proteína do albúmen e da gema e o teor de colesterol e a coloração da gema. A produção, o peso do ovo, a massa de ovo e as conversões por massa e por dúzia de ovos, bem como a qualidade interna e externa dos ovos, não foram influenciados pelos níveis de óleo de linhaça na ração. Do mesmo modo, não houve efeito da inclusão de óleo de linhaça sobre a composição química dos ovos e somente a coloração da gema foi intensificada quando utilizados níveis acima de 1% de óleo de linhaça na dieta. A adição de até 2% de óleo de linhaça na ração não altera o desempenho de poedeiras semipesadas nem a qualidade interna e externa e o teor de colesterol dos ovos.<br>This experiment was carried out to evaluate the influence of the linseed oil addition in replacement of soybean oil in laying hens diets on performance and internal and external egg quality. A total of 192 laying hens Bovans Godline line with 29 week-old, were distributed to six treatments, that consisted of a control diet (without vegetal oil) and of five diets containing 2% of linseed oil in replacement of 0, 25, 50, 75 and 100% of soybean oil, generating levels of 0.0, 0.5, 1.0, 1.5 and 2.0 % of linseed oil in the diets. The evaluated parameters were: production (PROD), egg weight (EW) and mass (EM), feed:egg mass ratio (FEM) and feed:egg dozen ratio (FED), albumen, yolk and shell weights and percentages, specific gravity, albumen and yolk dry matter, ashes and protein, yolk cholesterol and coloration. The production , EW, EM, FEM and FED, as for internal and external egg quality, were not influenced by the linseed oil levels in the diet. Likewise, no effect was observed on egg chemical composition and only yolk coloration was intensified with the levels above 1% of linseed oil in the diet. The addition of up to 2% f linseed oil on diet did not alter the performance on semi-heavy laying hens, and the internal and external egg quality and cholesterol