scholarly journals Influence of group B streptococci on piglet pulmonary artery response to bradykinin

1999 ◽  
Vol 86 (1) ◽  
pp. 61-65 ◽  
Author(s):  
Richard M. Whitehurst ◽  
Rachel Laskey ◽  
Ronald N. Goldberg ◽  
Donald Herbert ◽  
Cornelius Van Breemen
Keyword(s):  
Pulmonary Artery ◽  
Contractile Response ◽  
Isometric Force ◽  
Control Group ◽  
Relaxed Controls ◽  
Vascular Response ◽  
Group B Streptococci ◽  
Resting Tension ◽  
Neonatal Group ◽  
Group B

To study whether a sepsis-induced increase in des-Arg9-bradykinin (des-Arg9-BK) and bradykinin (BK) B1-receptor activity participates in the observed increase in pulmonary vascular resistance in neonatal group B streptococcal sepsis (GBS), isometric force bioassays of pulmonary artery (PA) rings were studied, after 4-h exposure to either Krebs or GBS, by using the following protocols: 1) BK dose-response curve, 2) vascular response to BK with N G-nitro-l-arginine methyl ester (l-NAME), and 3) response to des-Arg9-BK (BK metabolite and B1 agonist). PA rings exposed to BK resulted in contraction in the GBS group and a decrease in resting tension in the Control group ( P = 0.034) at a concentration of 10−5 M. GBS-treated PA rings contracted more to des-Arg9-BK than did Controls ( P < 0.001). BK (10−6 M) relaxed preconstricted PA rings incubated in GBS less than BK relaxed Controls ( P < 0.001), and preincubation withl-NAME decreased relaxation in both. These results suggest that GBS decreased endothelium-dependent BK relaxation and increased contractile response to des-Arg9-BK. We speculate that this occurs secondary to upregulation of B1 receptors reflected by B1-agonist-mediated PA contraction.

Existence of optimal controls for systems of controlled forward-backward doubly SDEs

2020 ◽  
Vol 28 (2) ◽  
pp. 93-112
Author(s):  
Abdelhakim Ninouh ◽  
Boulakhras Gherbal ◽  
Nassima Berrouis
Keyword(s):  
Weak Convergence ◽  
Control Problem ◽  
Optimality Conditions ◽  
Sufficient Optimality Conditions ◽  
Optimal Controls ◽  
Convexity Condition ◽  
Relaxed Controls ◽  
Relaxed Control ◽  
Doubly Stochastic ◽  
Existence Of Optimal Controls

AbstractWe wish to study a class of optimal controls for problems governed by forward-backward doubly stochastic differential equations (FBDSDEs). Firstly, we prove existence of optimal relaxed controls, which are measure-valued processes for nonlinear FBDSDEs, by using some tightness properties and weak convergence techniques on the space of Skorokhod {\mathbb{D}} equipped with the S-topology of Jakubowski. Moreover, when the Roxin-type convexity condition is fulfilled, we prove that the optimal relaxed control is in fact strict. Secondly, we prove the existence of a strong optimal controls for a linear forward-backward doubly SDEs. Furthermore, we establish necessary as well as sufficient optimality conditions for a control problem of this kind of systems. This is the first theorem of existence of optimal controls that covers the forward-backward doubly systems.

scholarly journals Regularity and Stability of Feedback Relaxed Controls

2021 ◽  
Vol 59 (5) ◽  
pp. 3118-3151
Author(s):  
Christoph Reisinger ◽  
Yufei Zhang
Keyword(s):  
Relaxed Controls

scholarly journals When are minimizing controls also minimizing relaxed controls?

2015 ◽  
Vol 35 (9) ◽  
pp. 4573-4592 ◽  
Author(s):  
Michele Palladino ◽  
◽  
Richard B. Vinter
Keyword(s):  
Relaxed Controls
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