Background: Hypoxia is one of the most frequently encountered stresses in health and disease. Methods: We compared the effects of an anti-β1 periodontal IgG (pIgG) and an authentic β1 adrenergic agonist, xamoterol, ...Background: Hypoxia is one of the most frequently encountered stresses in health and disease. Methods: We compared the effects of an anti-β1 periodontal IgG (pIgG) and an authentic β1 adrenergic agonist, xamoterol, on isolated myocardium from rat atria contractility. We used an ELISA assay to measure the generation of PGE2 in vitro after the addition of either the antibody or the adrenergic agonist. We analyzed the myocardium histopathologically in the presence of both the antibody and/or the adrenergic agonist drug during normoxia, hypoxia and reperfusion conditions. Results: PGE2 generation increased during the hypoxia and was unchanged during reoxygenation period compared with the production of this prostanoid in atria during normoxia condition. A β1 specific adrenoceptor antagonist atenolol and the β1 synthetic peptide abrogated the increment of the prostanoid in the presence of pIgG but only atenolol due to it in the presence of xamoterol. The increment of PGE2 was dependent on the activation of cox-1 and cox-2 isoforms. Moreover, cox-2 was more active and produced more increments in the production of PGE2 in the presence of the pIgG than cox-1 activation. Histopathologically, studies of myocardium specimens during these different periods of the experimental protocol: basal (B), hypoxia (H) and reoxygenation (R), were also performed and showed tissue necrosis and edematization at the myocardium level. Conclusion: The phenomenon studied here supports the notion that PGE2 may be responsible for tissue edematization. PGE2 maybe acts as a beneficial modulator in the myocardium and prevents a major injury of it. The inflammation damage to the heart organ and cardiomyocytes caused by the actions of the antibodies in the course of heart lesions provoked by cardiovascular autoimmune disease, explains some of these results obtained in the present experiments. Further studies will be needed to establish the real role of PGE2 during hypoxia injury of the heart in the course of autoimmune diseases.展开更多
Antiphospholipid syndrome(APS)or Hughes syndrome is an acquired thromboinflammatory disorder.Clinical criteria of APS diagnosis are large-and small-vessel thrombosis as well as obstetric problems;laboratory criteria a...Antiphospholipid syndrome(APS)or Hughes syndrome is an acquired thromboinflammatory disorder.Clinical criteria of APS diagnosis are large-and small-vessel thrombosis as well as obstetric problems;laboratory criteria are the presence of antiphospholipid antibodies(lupus anticoagulant,anticardiolipin antibodies and anti-β2-glycoprotein-1).The presence of at least 1 clinical and 1 laboratory criterion allows definitive diagnosis of APS.Primary APS is diagnosed in patients without features of connective tissue disease;secondary APS is diagnosed in patients with clinical signs of autoimmune disease.A high frequency of catastrophic APS as well as a high tendency to evolve from primary APS to secondary syndrome during the course of lupus and lupus-like disease is a feature of pediatric APS.The most characteristic clinical presentation of APS in the pediatric population is venous thrombosis,mainly in the lower limbs,and arterial thrombosis causing ischemic brain stroke.Currently,no diagnostic criteria for pediatric APS exist,which probably results in an underestimation of the problem.Similarly,no therapeutic procedures for APS specific for children have yet been established.In the present literature review,we discussed data concerning APS in children and its role in cerebrovascular diseases,including pediatric arterial ischemic stroke,migraine and cerebral venous thrombosis.展开更多
文摘Background: Hypoxia is one of the most frequently encountered stresses in health and disease. Methods: We compared the effects of an anti-β1 periodontal IgG (pIgG) and an authentic β1 adrenergic agonist, xamoterol, on isolated myocardium from rat atria contractility. We used an ELISA assay to measure the generation of PGE2 in vitro after the addition of either the antibody or the adrenergic agonist. We analyzed the myocardium histopathologically in the presence of both the antibody and/or the adrenergic agonist drug during normoxia, hypoxia and reperfusion conditions. Results: PGE2 generation increased during the hypoxia and was unchanged during reoxygenation period compared with the production of this prostanoid in atria during normoxia condition. A β1 specific adrenoceptor antagonist atenolol and the β1 synthetic peptide abrogated the increment of the prostanoid in the presence of pIgG but only atenolol due to it in the presence of xamoterol. The increment of PGE2 was dependent on the activation of cox-1 and cox-2 isoforms. Moreover, cox-2 was more active and produced more increments in the production of PGE2 in the presence of the pIgG than cox-1 activation. Histopathologically, studies of myocardium specimens during these different periods of the experimental protocol: basal (B), hypoxia (H) and reoxygenation (R), were also performed and showed tissue necrosis and edematization at the myocardium level. Conclusion: The phenomenon studied here supports the notion that PGE2 may be responsible for tissue edematization. PGE2 maybe acts as a beneficial modulator in the myocardium and prevents a major injury of it. The inflammation damage to the heart organ and cardiomyocytes caused by the actions of the antibodies in the course of heart lesions provoked by cardiovascular autoimmune disease, explains some of these results obtained in the present experiments. Further studies will be needed to establish the real role of PGE2 during hypoxia injury of the heart in the course of autoimmune diseases.
文摘Antiphospholipid syndrome(APS)or Hughes syndrome is an acquired thromboinflammatory disorder.Clinical criteria of APS diagnosis are large-and small-vessel thrombosis as well as obstetric problems;laboratory criteria are the presence of antiphospholipid antibodies(lupus anticoagulant,anticardiolipin antibodies and anti-β2-glycoprotein-1).The presence of at least 1 clinical and 1 laboratory criterion allows definitive diagnosis of APS.Primary APS is diagnosed in patients without features of connective tissue disease;secondary APS is diagnosed in patients with clinical signs of autoimmune disease.A high frequency of catastrophic APS as well as a high tendency to evolve from primary APS to secondary syndrome during the course of lupus and lupus-like disease is a feature of pediatric APS.The most characteristic clinical presentation of APS in the pediatric population is venous thrombosis,mainly in the lower limbs,and arterial thrombosis causing ischemic brain stroke.Currently,no diagnostic criteria for pediatric APS exist,which probably results in an underestimation of the problem.Similarly,no therapeutic procedures for APS specific for children have yet been established.In the present literature review,we discussed data concerning APS in children and its role in cerebrovascular diseases,including pediatric arterial ischemic stroke,migraine and cerebral venous thrombosis.
