Objective-Epoxyeicosatrienoic acids (EETs) have been shown to have antiinflammatory effects and therefore may play a role in preventing vascular inflammatory and atherosclerotic diseases. Soluble epoxide hydrolase (s-EH) converts EETs into less bioactive dihydroxyeicosatrienoic acids. Thus, inhibition of s-EH can prevent degradation of EETs and prolong their effects. The present study aimed to test the hypothesis that inhibition of s-EH has vascular protective effects. Methods and Results-Six-month-old apolipoprotein E-deficient mice were chronically infused with angiotensin II (1.44 mg/kg/d) for 4 weeks to induce abdominal aortic aneurysm (AAA), accelerate atherosclerosis development and carotid artery ligation-induced vascular remodeling. The mice were treated with a novel s-EH inhibitor, AR9276 (1.5 g/L in drinking water) or vehicle for 4 weeks. The results demonstrated that AR9276 significantly reduced the rate of AAA formation and atherosclerotic lesion area, but had no effect on ligation-induced carotid artery remodeling. These effects were associated with a reduction of serum lipid, IL-6, murine IL-8-KC, and IL-1␣, and downregulation of gene expressions of ICAM-1, VCAM-1, and IL-6 in the arterial wall. Key Words: epoxyeicosatrienoic acids Ⅲ soluble epoxide hydrolase Ⅲ dyslipidemia Ⅲ atherosclerosis Ⅲ abdominal aorta aneurysm Ⅲ inflammatory markers A rachidonic acid can be metabolized by 3 major oxidative pathways: cyclooxygenase (COX) forming prostaglandins; lipoxygenase (LOX) forming hydroxyeicosatetraenoic acids (HETEs) and leukotrienes; and cytochrome P-450 monooxygenase forming epoxides and HETEs. 1 The COX and LOX pathways have been extensively studied, and their eicosanoid products have been shown to play important roles in a variety of biological processes such as inflammation, cell proliferation, and intracellular signaling. In contrast, less is known about the "third pathway" of arachidonic acid metabolism. Recently, epoxyeicosatrienoic acids (EETs), the cytochrome P450 metabolites of arachidonic acid, have received increasing attention for multiple beneficial biological functions, including vasodilation, antiinflammation, and inhibition of proliferation and migration of vascular smooth muscle cells. 1,2 Based on these properties, it has been postulated that EETs may exert therapeutic benefits in inflammatory vascular diseases, such as atherosclerosis. 2,3 Soluble epoxide hydrolase (s-EH) converts EETs into their corresponding dihydroxyeicosatrienoic acids (DHETs), which are generally thought to have reduced biological activity relative to EETs, and hydration of the EETs by s-EH is a dominant mechanism whereby their activity can be reduced. 4 Thus, inhibition of s-EH could be a promising therapeutic target for amplifying the beneficial effects of EETs. 4 Indeed, s-EH inhibitors have been demonstrated to lower blood pressure in hypertension, 5,6 decrease hypertension-induced renal damage 7 and cerebral ischemia injury, 8 attenuate vascular smooth muscle cell proliferation, 9 and reduce tissue...

AR9281, a potent and selective inhibitor of soluble epoxide hydrolase (s-EH), is in clinical development targeting hypertension and type 2 diabetes. The safety, pharmacokinetics, and pharmacodynamics of AR9281 were evaluated in double-blind, randomized, placebo-controlled, ascending, single oral dose (10-1000 mg) and multiple dose (100-400 mg every 8 hours for 7 days) studies in healthy subjects. AR9281 was well tolerated, and no dose-related adverse events were observed during either study. The drug was rapidly absorbed with a mean terminal half-life ranging from 3 to 5 hours. The area under the plasma concentration-time curve increased in an approximately dose-proportional manner up to the 500-mg dose and exhibited a greater than dose linearity at higher doses. AR9281 directly and dose-dependently inhibited blood s-EH activity with 90% inhibition or greater over an 8-hour period at the 250-mg dose and over a 12-hour period at the 500-mg dose. Multiple doses of AR9281 ranging from 100 to 400 mg every 8 hours resulted in a sustained inhibition of s-EH activity at 90% or greater during the trough. The current studies provide proof of safety and target inhibition of AR9281 in healthy subjects. AR9281 pharmacokinetic and pharmacodynamic characteristics support a twice-daily or thrice-daily dosing regimen in patients.

SummaryHost cell invasion by Toxoplasma gondii is critically dependent upon adhesive proteins secreted from the micronemes. Proteolytic trimming of microneme contents occurs rapidly after their secretion onto the parasite surface and is proposed to regulate adhesive complex activation to enhance binding to host cell receptors. However, the proteases responsible and their exact function are still unknown. In this report, we show that T. gondii tachyzoites lacking the microneme subtilisin protease TgSUB1 have a profound defect in surface processing of secreted microneme proteins. Notably parasites lack protease activity responsible for proteolytic trimming of MIC2, MIC4 and M2AP after release onto the parasite surface. Although complementation with fulllength TgSUB1 restores processing, complementation of Dsub1 parasites with TgSUB1 lacking the GPI anchor (Dsub1::DGPISUB1) only partially restores microneme protein processing. Loss of TgSUB1 decreases cell attachment and in vitro gliding efficiency leading to lower initial rates of invasion. Dsub1 and Dsub1::DGPISUB1 parasites are also less virulent in mice. Thus TgSUB1 is involved in micronemal protein processing and regulation of adhesive properties of macromolecular adhesive complexes involved in host cell invasion.

How can humans acquire relational representations that enable analogical inference and other forms of high-level reasoning? Using comparative relations as a model domain, we explore the possibility that bottom-up learning mechanisms applied to objects coded as feature vectors can yield representations of relations sufficient to solve analogy problems. We introduce Bayesian analogy with relational transformations (BART) and apply the model to the task of learning first-order comparative relations (e.g., larger, smaller, fiercer, meeker) from a set of animal pairs. Inputs are coded by vectors of continuousvalued features, based either on human magnitude ratings, normed feature ratings (De Deyne et al., 2008), or outputs of the topics model (Griffiths, Steyvers, & Tenenbaum, 2007). Bootstrapping from empirical priors, the model is able to induce first-order relations represented as probabilistic weight distributions, even when given positive examples only. These learned representations allow classification of novel instantiations of the relations and yield a symbolic distance effect of the sort obtained with both humans and other primates. BART then transforms its learned weight distributions by importance-guided mapping, thereby placing distinct dimensions into correspondence. These transformed representations allow BART to reliably solve 4-term analogies (e.g., larger:smaller::fiercer:meeker), a type of reasoning that is arguably specific to humans. Our results provide a proof-of-concept that structured analogies can be solved with representations induced from unstructured feature vectors by mechanisms that operate in a largely bottom-up fashion. We discuss potential implications for algorithmic and neural models of relational thinking, as well as for the evolution of abstract thought. Keywords: analogy, relation learning, generalization, Bayesian modelsSupplemental materials: http://dx.doi.org/10.1037/a0028719.supp One of the hallmarks of human reasoning is the ability to form representations of relations between entities and then to reason about the higher order relations between these relations. Whereas concepts such as larger and smaller, for example, are first-order relations, potentially derivable by comparing features of individual objects, a relation such as opposite is a higher order relation between relations (Gentner, 1983). The capacity to represent and reason with higher order relations has been considered central to human analogical thinking

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