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Newly Developed Chronic Conditions and Changes in Health‐Related Quality of Life in Postmenopausal Women 下载免费PDF全文
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The Patient Protection and Affordable Care Act of 2010 (ACA) is revamping the access, quality, and financing of the health and mental health systems. However, its impact on training and education in clinical psychology is unclear. This article aims to identify specific components of the ACA, in particular the Mental and Behavioral Health Education and Training Grants, that are expected to affect training and education in the field. The article further connects the ACA with four paradigm shifts in clinical psychology that have broad implications for training and education—evidence‐based practices, research methodology, interprofessionalism, and the quality indicator movement. The overarching goal of this article is to begin timely discussions on the future directions of the field under the current healthcare reform. 相似文献
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Rebecca L. Charles Olena Rudyk Oleksandra Prysyazhna Alisa Kamynina Jun Yang Christophe Morisseau Bruce D. Hammock Bruce A. Freeman Philip Eaton 《Proceedings of the National Academy of Sciences of the United States of America》2014,111(22):8167-8172
Soluble epoxide hydrolase (sEH) is inhibited by electrophilic lipids by their adduction to Cys521 proximal to its catalytic center. This inhibition prevents hydrolysis of the enzymes’ epoxyeicosatrienoic acid (EET) substrates, so they accumulate inducing vasodilation to lower blood pressure (BP). We generated a Cys521Ser sEH redox-dead knockin (KI) mouse model that was resistant to this mode of inhibition. The electrophilic lipid 10-nitro-oleic acid (NO2-OA) inhibited hydrolase activity and also lowered BP in an angiotensin II-induced hypertension model in wild-type (WT) but not KI mice. Furthermore, EET/dihydroxy-epoxyeicosatrienoic acid isomer ratios were elevated in plasma from WT but not KI mice following NO2-OA treatment, consistent with the redox-dead mutant being resistant to inhibition by lipid electrophiles. sEH was inhibited in WT mice fed linoleic acid and nitrite, key constituents of the Mediterranean diet that elevates electrophilic nitro fatty acid levels, whereas KIs were unaffected. These observations reveal that lipid electrophiles such as NO2-OA mediate antihypertensive signaling actions by inhibiting sEH and suggest a mechanism accounting for protection from hypertension afforded by the Mediterranean diet.Soluble epoxide hydrolase (sEH) has a conserved cysteine (Cys521) proximal to its catalytic center. This cysteine can undergo Michael addition with electrophilic lipids, which inhibits hydrolysis of the enzyme’s epoxyeicosatrienoic acid (EET) substrates (1). This in turn elevates EET levels, which mediate blood vessel dilation and lowers blood pressure (BP), especially in the setting of hypertension (2, 3). Diverse sEH inhibitors limit injury in a variety of diseases (4), providing broad cardiovascular protection (5) against hypertension (6, 7), ischemia and reperfusion injury (8, 9), hypertrophy, and heart failure (10), as well as inflammation (11, 12). Consistent with the therapeutic potential of hydrolase inhibitors, sEH null mice are protected from pathological interventions (13). Conversely, genetic alterations that promote enhanced hydrolase activity are a risk factor for human heart failure (14).The endogenous lipid electrophile 10-nitrooctadec-9-enoic acid (nitro-oleic acid, NO2-OA) inhibits sEH in vitro (1). NO2-OA and other fatty acid nitroalkenes appear to signal via pleiotropic mechanisms including targeting and activating peroxisome proliferator-activated receptor gamma (PPARγ), the Kelch-like erythroid cell-derived protein with CNC homology (EHC)-associated protein-1 (Keap1), and nuclear factor (erythroid-derived)-like-2 (Nrf2)-regulated antioxidant response genes and inhibiting proinflammatory gene expression regulated by nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) (15, 16). Nitroalkenes are produced by radical addition of nitrogen dioxide (·NO2) to one or more of the olefinic carbons of an unsaturated fatty acid. Nitrogen dioxide is both a product of oxidative inflammatory reactions involving nitric oxide (NO) and nitrite and the acidification nitrite. When the electron-withdrawing nitro group is bonded to alkenyl groups, this confers an electrophilic reactivity to fatty acids (17, 18). Thus, fatty acid nitroalkenes can modify proteins covalently via reversible Michael addition reactions that overall serves to link cellular metabolic and redox homeostasis with the posttranslational regulation of target protein function.Nitro fatty acids, which have been detected endogenously in plasma and urine of humans, animal models, and plants (19–21), mediate salutary cardiovascular signaling actions (22). For example they relax blood vessels, attenuate platelet activation, and reduce inflammation via cyclic guanosine monophosphate (cGMP)-independent mechanisms (23, 24). Of relevance, the Mediterranean diet is characterized by high consumption of unsaturated fatty acids, especially from olive oil and fish rich in oleic and linoleic acid, together with vegetables rich in nitrite and nitrate (25). The acidic and low-oxygen conditions in the stomach provide an environment for efficient nitration of such unsaturated fatty acids by nitrite (26).NO2-OA normalizes blood pressure in an angiotensin (Ang) II-induced murine model of hypertension via undefined mechanisms (27). This was notable as pharmacological inhibitors of sEH also lower BP in murine hypertension, including salt- or Ang II-induced models (6, 7). As NO2-OA inhibits sEH, we hypothesized that this mechanism may account for BP lowering in the setting of hypertension. Furthermore, as the Mediterranean diet both contains nitro fatty acids and can elevate their endogenous generation, this mechanism may contribute to dietary-induced BP decreases that in turn will reduce the risk of adverse cardiovascular event (28).Given the complexity of causally establishing whether nitro fatty acids lower BP by inhibiting sEH, especially in the setting of dietary-induced endogenous fatty acid nitration, we generated a Cys521Ser sEH knockin (KI) mouse. This “redox-inactive” sEH thiol mutant, rendered insensitive to adductive inhibition by lipid electrophiles in vitro, provided a novel model system for testing the impact of lipid nitroalkenes on sEH hydrolysis of vasoactive EET species and downstream physiological responses (1). The data reveal that nitro fatty acids, applied exogenously as a pharmacological agent or generated endogenously as part of the Mediterranean diet, inhibit sEH to elevate plasma EETs, which in turn lower BP. 相似文献
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Shao D Oka S Brady CD Haendeler J Eaton P Sadoshima J 《Journal of molecular and cellular cardiology》2012,52(3):550-558
Oxidative stress is presumed to be involved in the pathogenesis of many diseases, including cardiovascular disease. However, oxidants are also generated in healthy cells, and increasing evidence suggests that they can act as signaling molecules. The intracellular reduction-oxidation (redox) status is tightly regulated by oxidant and antioxidant systems. Imbalance between them causes oxidative or reductive stress which triggers cellular damage or aberrant signaling, leading to dysregulation. In this review, we will briefly summarize the aspects of ROS generation and neutralization mechanisms in the cardiovascular system. ROS can regulate cell signaling through oxidation and reduction of specific amino acids within proteins. Structural changes during post-translational modification allow modification of protein activity which can result in altered cellular function. We will focus on the molecular basis of redox protein modification and how this regulatory mechanism affects signal transduction in the cardiovascular system. Finally, we will discuss some techniques applied to monitoring redox status and identifying redox-sensitive proteins in the heart. This article is part of a Special Section entitled "Post-translational Modification." 相似文献
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Vagnini MT Smeigh AL Blakemore JD Eaton SW Schley ND D'Souza F Crabtree RH Brudvig GW Co DT Wasielewski MR 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(39):15651-15656
Photodriving the activity of water-oxidation catalysts is a critical step toward generating fuel from sunlight. The design of a system with optimal energetics and kinetics requires a mechanistic understanding of the single-electron transfer events in catalyst activation. To this end, we report here the synthesis and photophysical characterization of two covalently bound chromophore-catalyst electron transfer dyads, in which the dyes are derivatives of the strong photooxidant perylene-3,4:9,10-bis(dicarboximide) (PDI) and the molecular catalyst is the Cp∗Ir(ppy)Cl metal complex, where ppy = 2-phenylpyridine. Photoexcitation of the PDI in each dyad results in reduction of the chromophore to PDI•- in less than 10 ps, a process that outcompetes any generation of 3∗PDI by spin-orbit-induced intersystem crossing. Biexponential charge recombination largely to the PDI-Ir(III) ground state is suggestive of multiple populations of the PDI•--Ir(IV) ion-pair, whose relative abundance varies with solvent polarity. Electrochemical studies of the dyads show strong irreversible oxidation current similar to that seen for model catalysts, indicating that the catalytic integrity of the metal complex is maintained upon attachment to the high molecular weight photosensitizer. 相似文献
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