Channels最新文献

{"title":"Elementary calcium signaling in arterial smooth muscle","authors":"Gang Fan, Yingqiu Cui, M. Gollasch, M. Kassmann","doi":"10.1080/19336950.2019.1688910","DOIUrl":"https://doi.org/10.1080/19336950.2019.1688910","url":null,"abstract":"ABSTRACT Vascular smooth muscle cells (VSMCs) of small peripheral arteries contribute to blood pressure control by adapting their contractile state. These adaptations depend on the VSMC cytosolic Ca2+ concentration, regulated by complex local elementary Ca2+ signaling pathways. Ca2+ sparks represent local, transient, rapid calcium release events from a cluster of ryanodine receptors (RyRs) in the sarcoplasmic reticulum. In arterial SMCs, Ca2+ sparks activate nearby calcium-dependent potassium channels, cause membrane hyperpolarization and thus decrease the global intracellular [Ca2+] to oppose vasoconstriction. Arterial SMC Cav1.2 L-type channels regulate intracellular calcium stores content, which in turn modulates calcium efflux through RyRs. Cav3.2 T-type channels contribute to a minor extend to Ca2+ spark generation in certain types of arteries. Their localization within cell membrane caveolae is essential. We summarize present data on local elementary calcium signaling (Ca2+ sparks) in arterial SMCs with focus on RyR isoforms, large-conductance calcium-dependent potassium (BKCa) channels, and cell membrane-bound calcium channels (Cav1.2 and Cav3.2), particularly in caveolar microdomains.","PeriodicalId":9750,"journal":{"name":"Channels","volume":null,"pages":null},"PeriodicalIF":3.3,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81619366","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"PI3Kα in cardioprotection: Cytoskeleton, late Na+ current, and mechanism of arrhythmias","authors":"P. Zhabyeyev, Xueyi Chen, B. Vanhaesebroeck, G. Oudit","doi":"10.1080/19336950.2019.1697127","DOIUrl":"https://doi.org/10.1080/19336950.2019.1697127","url":null,"abstract":"ABSTRACT PI 3-kinase α (PI3Kα) is a lipid kinase that converts phosphatidylinositol-4,5-bisphosphate (PIP2) to phosphatidylinositol-3,4,5-triphosphate (PIP3). PI3Kα regulates a variety of cellular processes such as nutrient sensing, cell cycle, migration, and others. Heightened activity of PI3Kα in many types of cancer made it a prime oncology drug target, but also raises concerns of possible adverse effects on the heart. Indeed, recent advances in preclinical models demonstrate an important role of PI3Kα in the control of cytoskeletal integrity, Na+ channel activity, cardioprotection, and prevention of arrhythmias.","PeriodicalId":9750,"journal":{"name":"Channels","volume":null,"pages":null},"PeriodicalIF":3.3,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77469432","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Role of the voltage sensor module in Nav domain IV on fast inactivation in sodium channelopathies: The implication of closed-state inactivation","authors":"T. Nakajima, Y. Kaneko, Tommy Dharmawan, M. Kurabayashi","doi":"10.1080/19336950.2019.1649521","DOIUrl":"https://doi.org/10.1080/19336950.2019.1649521","url":null,"abstract":"ABSTRACT The segment 4 (S4) voltage sensor in voltage-gated sodium channels (Navs) have domain-specific functions, and the S4 segment in domain DIV (DIVS4) plays a key role in the activation and fast inactivation processes through the coupling of arginine residues in DIVS4 with residues of putative gating charge transfer center (pGCTC) in DIVS1-3. In addition, the first four arginine residues (R1-R4) in Nav DIVS4 have position-specific functions in the fast inactivation process, and mutations in these residues are associated with diverse phenotypes of Nav-related diseases (sodium channelopathies). R1 and R2 mutations commonly display a delayed fast inactivation, causing a gain-of-function, whereas R3 and R4 mutations commonly display a delayed recovery from inactivation and profound use-dependent current attenuation, causing a severe loss-of-function. In contrast, mutations of residues of pGCTC in Nav DIVS1-3 can also alter fast inactivation. Such alterations in fast inactivation may be caused by disrupted interactions of DIVS4 with DIVS1-3. Despite fast inactivation of Navs occurs from both the open-state (open-state inactivation; OSI) and closed state (closed-state inactivation; CSI), changes in CSI have received considerably less attention than those in OSI in the pathophysiology of sodium channelopathies. CSI can be altered by mutations of arginine residues in DIVS4 and residues of pGCTC in Navs, and altered CSI can be an underlying primary biophysical defect of sodium channelopathies. Therefore, CSI should receive focus in order to clarify the pathophysiology of sodium channelopathies.","PeriodicalId":9750,"journal":{"name":"Channels","volume":null,"pages":null},"PeriodicalIF":3.3,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88086139","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Call to Peace: How Third-Party Actors and Frameworks Impacted the Peace Processes of Northern Ireland and Colombia","authors":"Esther K Holm","doi":"10.15385/JCH.2018.3.1.3","DOIUrl":"https://doi.org/10.15385/JCH.2018.3.1.3","url":null,"abstract":"Northern Ireland and Colombia both serve as excellent case studies on how the end of the Cold War impacted peace processes. Both countries experienced conflicts that begun in the Cold War era and underwent peace processes in the post-Cold War era. As such, studying them reveals characteristics of post-Cold War peace processes. For example, both Northern Ireland and Colombia showcase the important role that third-party actors play in modern conflict mediation. Both countries benefited greatly from mediation conducted by international organization, other countries, and individuals. Furthermore, both countries demonstrate the importance of frameworks in any successful peace negotiation. This paper argues that third-party actors greatly benefit peace processes and that a detailed framework is imperative to a successful peace process.","PeriodicalId":9750,"journal":{"name":"Channels","volume":null,"pages":null},"PeriodicalIF":3.3,"publicationDate":"2018-12-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88645946","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"21st Century Javelin Catchers: White House Organization and the Chief of Staff","authors":"Molly Schwall","doi":"10.15385/JCH.2018.3.1.5","DOIUrl":"https://doi.org/10.15385/JCH.2018.3.1.5","url":null,"abstract":"This research discusses the impact that White House organization has on the roles of chief of staff. The paper begins with an overview of the major models of White House organization and the roles typically performed by chief of staff. By examining the impact of organizational difficulties faced by the chiefs of staff in the presidencies of George W. Bush and Barack Obama through case studies, this research seeks to situate the major roles of chief of staff within White House organization to examine the impact of organization on chief of staff performance. The findings of the case studies suggest that the formalistic model of White House organization best serves the roles of chief of staff by providing clear, delineated lines of organization with specific tasks for White House staffing. The paper concludes by examining the presidency of Donald Trump and the organizational difficulties faced during the first year of his administration.","PeriodicalId":9750,"journal":{"name":"Channels","volume":null,"pages":null},"PeriodicalIF":3.3,"publicationDate":"2018-12-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74592150","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Speech Act of Naming in Context: A Linguistic Study of Naming in the Old Testament","authors":"L. Yost","doi":"10.15385/JCH.2018.3.1.2","DOIUrl":"https://doi.org/10.15385/JCH.2018.3.1.2","url":null,"abstract":"This research sought to study the act of naming in the context of the Old Testament using speech act theory. To analyze naming as presented in the Old Testament, I first studied the Hebrew words qārāʾ and šēm, creating from my findings the following extended definition: (naming is) the act of giving a name within particular specified circumstances by one with authority over the name-receiver, whose authority is respected by others such that the name spoken is hence used to identify and represent the receiver. This, along with an understanding of Alston (2000) and the example of Arcadi (2013), shaped a schema of illocutionary rules and conditions that I then tested in nine case studies of naming throughout the Old Testament. Key components include particular circumstances, necessary conditions and authority, and the occurrence within a community. Ultimately, I conclude naming as presented in the Old Testament is in fact a speech act that is subject to particular rules and carries great importance.","PeriodicalId":9750,"journal":{"name":"Channels","volume":null,"pages":null},"PeriodicalIF":3.3,"publicationDate":"2018-12-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88022139","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Eyes on the Money: How Realist Economic Policy Facilitates the Modern Surveillance State in the USA and the PRC","authors":"Benjamin Warder","doi":"10.15385/JCH.2018.3.1.7","DOIUrl":"https://doi.org/10.15385/JCH.2018.3.1.7","url":null,"abstract":"This paper examines the manner in which the United States of America and the People’s Republic of China, as the world’s leading economic superpowers, pursue a generally realist international relations approach to maintaining and securing their bases of economic power, and how this purpose translates into the development and proliferation of Closed Circuit Television (CCTV) camera networks in major cities as a means of protecting those cities as economic hubs crucial to the national economy. Two research questions guide the paper. First, how does each state demonstrate realist policies in the process of securing economic centers and the overall protection of its economy? Second, how does the use of CCTV contribute to the security and functionality of major economic centers in each state? Through a case comparison, the study examines the two countries on the bases of differences in governmental ideological orientation, justification of continued government-operated CCTV proliferation, and likelihood of altering that proliferation by civic means, ultimately concluding that as the international system retains its competitive atmosphere, surveillance state policies will continue to be the norm as national government purpose to maintain bases of global power.","PeriodicalId":9750,"journal":{"name":"Channels","volume":null,"pages":null},"PeriodicalIF":3.3,"publicationDate":"2018-12-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90249186","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Seeing Green Through the Eyes of National Oil Companies: A Comparison of Gazprom’s and Petrobras’ Environmental Sustainability","authors":"J. A. Thompson","doi":"10.15385/jch.2018.3.1.6","DOIUrl":"https://doi.org/10.15385/jch.2018.3.1.6","url":null,"abstract":"The case studies of Gazprom and Petrobras are used to compare the interaction and relation between national oil companies, the state government and environmental policy. Specifically the paper seeks to address how the policy and interaction between the state government and the NOCs affect sustainable development of the preservation of the environment. The methodology used is set out by senior research international scholar, Eduardo Viola. He examines the state government’s position on the climate through three criteria: reduction of greenhouse gas (GHG) emissions, domestic climate policies and the state’s international standing on the issue. The United Nations Framework Convention on Climate Change (UNFCCC) GHG Inventory data, Brazil and Russia’s energy strategies and a third-party newspaper reporter will all be used to compare the two case studies. The research discovers that protection of the natural environment is an area of lesser importance to more predominant state goals of energy development and independence and the foreign policy agendas of legitimizing or leveraging the state’s energy capabilities towards other nations.","PeriodicalId":9750,"journal":{"name":"Channels","volume":null,"pages":null},"PeriodicalIF":3.3,"publicationDate":"2018-12-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80998543","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Public Principles and Economic Legacy","authors":"Stanley G. Schwartz","doi":"10.15385/JCH.2018.2.2.2","DOIUrl":"https://doi.org/10.15385/JCH.2018.2.2.2","url":null,"abstract":"Abstract 2018 will mark the 60 th anniversary of the publication of Public Principles of Public Debt. The Nobel-prize winning economist’s first book conflicted with the Keynesian orthodoxy of the day, and added fresh ideas to an ongoing debate over the fundamentals of public debt theory. This paper seeks to outline the dialogue among leading economists surrounding public debt since the publication of Public Principles of Public Debt, examining the major schools of thought and their development. The ideas of John Maynard Keynes, James Buchanan, and Richard Barro will receive attention, without neglecting other significant contributions. The paper will conclude by examining current papers in the field of public debt theory, considering them in light of the noted historical ideas. Despite the foundational nature of James Buchanan’s work in public finance, his cautions regarding the assumptions, methodology, incentives, and institutions of public debt, particularly his integration of public choice, are not treated centrally in many ongoing analyses. The empirical nature of much current public debt theory and research has led away from the presuppositional roots of the public debt debate. Renewed awareness of the historical and theoretical realities of public debt theory will be valuable for the field, and can provide reinvigorated application of public choice. This paper works toward those goals, examining the 60 years of public debt theory history since the publication of James Buchanan’s Public Principles of Public Debt and considering current work in the field.","PeriodicalId":9750,"journal":{"name":"Channels","volume":null,"pages":null},"PeriodicalIF":3.3,"publicationDate":"2018-04-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90330447","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Four-Legged Megalosaurus and Swimming Brontosaurs","authors":"Jordan C. Oldham","doi":"10.15385/jch.2018.2.2.5","DOIUrl":"https://doi.org/10.15385/jch.2018.2.2.5","url":null,"abstract":"Thomas Kuhn in his famous work The Structure of Scientific Revolutions laid out the framework for his theory of how science changes. At the advent of dinosaur paleontology fossil hunters like Gideon Mantell discovered some of the first dinosaurs like Iguanodon and Megalosaurus. Through new disciples like Georges Cuvier’s comparative anatomy lead early dinosaur paleontologist to reconstruct them like giant reptiles of absurd proportions. This lead to the formation of a new paradigm that prehistoric animals like dinosaurs existed and eventually went extinct. The first reconstructions of dinosaur made them to look like giant counterparts of their modern cousins. Then in 1841, Richard Owen coined the term dinosaur, and put the newly discovered dinosaurs into a special group based on similar morphological characteristics. He reconstructed them to look like giant elephant like reptiles. They were slow, sluggish, and their tales dragged the ground. Then in 1858, William Foulke and Joseph Leidy discovered the dinosaur Hadrosaurus which had morphological characteristics that hindered the animal from being quadrupedal. As a result a new paradigm was formed and some dinosaurs were lifted off the ground. They were reconstructed to look like giant reptilian kangaroos in stance, but they were still considered slow, sluggish, with tails still dragging behind them. This paradigm persisted until the 1960’s when paleontologist John Ostrom realized that there was an anomaly within dinosaur paleontology. The environments that dinosaurs inhabited did not match with the reconstructions of swamp dwelling animals, and dinosaur anatomy also did not match those reconstructions. Ostrom’s discovery and description of Deinonychus with its very bird like skeleton lead him to conclude that dinosaurs were energetic, and probably endothermic. This resulted in a crisis which lead other paleontologist to research this anomaly. More discoveries proved Ostrom’s new paradigm and dinosaur paleontology underwent a scientific revolution from the 1960’s to the 1980’s. Formally termed the dinosaur renaissance this revolution lead to dinosaurs being reconstructed as active, intelligent animals no longer with their tails dragging behind them.","PeriodicalId":9750,"journal":{"name":"Channels","volume":null,"pages":null},"PeriodicalIF":3.3,"publicationDate":"2018-04-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84895719","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}