Cellular bases for human atrial fibrillation

Atrial fibrillation (AF) causes substantial morbidity and mortality. It may be triggered and sustained by either reentrant or nonreentrant electrical activity. Human atrial cellular refractory period is shortened in chronic AF, likely aiding reentry. The ionic and molecular mechanisms are not fully understood and may include increased inward rectifier K<sup>+</sup> current and altered Ca<sup>2+</sup> handling. Heart failure, a major cause of AF, may involve arrhythmogenic atrial electrical remodeling, but the pattern is unclear in humans. Beta-blocker therapy prolongs atrial cell refractory period; a potentially antiarrhythmic influence, but the ionic and molecular mechanisms are unclear. The search for drugs to suppress AF without causing ventricular arrhythmias has been aided by basic studies of cellular mechanisms of AF. It remains to be seen whether such drugs will improve patient treatment

Electrophysiological and arrhythmogenic effects of 5-hydroxytryptamine on human atrial cells are reduced in atrial fibrillation

5-Hydroxytryptamine (5-HT) is proarrhythmic in atrial cells from patients in sinus rhythm (SR) via activation of 5-HT<sub>4</sub> receptors, but its effects in atrial cells from patients with atrial fibrillation (AF) are unknown. The whole-cell perforated patch-clamp technique was used to record L-type Ca<sup>2+</sup> current (<i>I</i><sub>CaL</sub>), action potential duration (APD) and arrhythmic activity at 37 °C in enzymatically isolated atrial cells obtained from patients undergoing cardiac surgery, in SR or with chronic AF. In the AF group, 5-HT (10 μM) produced an increase in <i>I</i><sub>CaL</sub> of 115 ± 21% above control (<i>n</i> = 10 cells, 6 patients) that was significantly smaller than that in the SR group (232 ± 33%; <i>p</i> 0.05; <i>n</i> = 27 cells, 12 patients). Subsequent co-application of isoproterenol (1 μM) caused a further increase in <i>I</i><sub>CaL</sub> in the AF group (by 256 ± 94%) that was greater than that in the SR group (22 ± 6%; p < 0.05). The APD at 50% repolarisation (APD<sub>50</sub>) was prolonged by 14 ± 3 ms by 5-HT in the AF group (<i>n</i> = 37 cells, 14 patients). This was less than that in the SR group (27 ± 4 ms; <i>p</i> < 0.05; <i>n</i> = 58 cells, 24 patients). Arrhythmic activity in response to 5-HT was observed in 22% of cells in the SR group, but none was observed in the AF group (p < 0.05). Atrial fibrillation was associated with reduced effects of 5-HT, but not of isoproterenol, on <i>I</i><sub>CaL</sub> in human atrial cells. This reduced effect on <i>I</i><sub>CaL</sub> was associated with a reduced APD<sub>50</sub> and arrhythmic activity with 5-HT. Thus, the potentially arrhythmogenic influence of 5-HT may be suppressed in AF-remodelled human atrium

Communicating Farm Animal Welfare Science: Wisconsin Dairy Producers' Attitudes Toward and Interest in Dairy Cattle Welfare

Research in the field of farm animal welfare science provides the foundation for the farm animal welfare assessment criteria and legislation that has been developing over the past fifty years, especially in the EU, England, Australia, and Canada. Research in this field involves using empirical evidence to make judgments about an animal's state of welfare; however, a number of studies, primarily in the EU, explore producer opinions and knowledge about farm animal welfare issues. Few comparable studies of US producers exist in the literature. The current study of Wisconsin (WI) dairy producers targeted producers' opinions about an animal's ability to experience the affective states of pain, fear, boredom, and frustration; their opinions about controversial on-farm management practices (e.g., tail docking and dehorning); their familiarity with farm animal welfare initiatives (e.g., university extension-sponsored conferences); their interest in learning about dairy cattle welfare; and how they currently obtain farm management information. Surveys were mailed to a computer-generated random sample (n=1,000) of WI dairy producers with a response rate of 48%. Results indicated that farm type, farm size, producer age, and producer education level impacted survey responses. This information could be used to develop welfare education strategies based on demographics and producers' preferred information sources

Effekt des anti-gangliosidären monoklonalen Antikörpers AA4 auf die intrazelluläre Calciumkonzentration in RBL-2H3-Zellen

Die Arbeit untersucht den Einfluß des Antikörpers AA4 auf den F$\varepsilon$RI-vermittelten Anstieg der intrazellulären Calciumkonzentration ($\Delta$[Ca$^{2+}$]$_{i}$) und die Rate der Serotoninfreisetzung in den RBL-2H3-Zellen. Eine Inhibition der F$\varepsilon$RI-vermittelten Serotoninfreisetzung und des F$\varepsilon$RI-vermittelten Anstieges der intrazellulären Calciumkonzentration durch den anti-gangliosidären monoklonalen Antikörper AA4 in RBL-2H3-Zellen konnte demonstriert werden. Die Untersuchungsergebnisse lassen eine mögliche regulatorische Funktion des Gangliosids GD$_{1b}$ auf die F$\varepsilon$RI-vermittelte Signaltransduktionsereignisse vermuten

Die Intervention von Drittstaaten im nicht-internationalen bewaffneten Konflikt

ZusammenfassungDie Intervention von Drittstaaten im nicht-internationalen bewaffneten KonfliktMeine Diplomarbeit befasst sich mit der Frage, wann ein nicht-internationaler bewaffneter Konflikt durch die Intervention von Drittstaaten internationalisiert wird.In der Einleitung präsentiere ich die von mir gewählte Methode Internationales Recht und Internationale Beziehungen (IR/IB). Jede Arbeit mit der Methode IR/IB basiert auf einem Modell oder einer Diagnose aus der Praxis, die grundlegende Struktur der Probleme wird genau umrissen, daher sind Gemeinsamkeiten verschiedener Probleme einfacher zu identifizieren. Im ersten Teil meiner Diplomarbeit kläre ich den Begriff des bewaffneten Konflikts, sowohl der internationale als auch der nicht-internationale bewaffnete Konflikt erfuhren in der Vergangenheit unterschiedliche Interpretationen, welche ich darstelle. Analysiert wird auch die Vorgangsweise der Urteilsfindung des International Court of Justice im Nicaragua Fall. Der Tadic Fall ist der eigentliche Auslöser für die wissenschaftliche Diskussion um die Internationalisierung nicht-internationaler bewaffneter Konflikte. Sowohl der ?effective control? als auch der ?overall control? Test werden analysiert, eigene Kritik des International Criminal Tribunal for the former Yugoslavia und eine flexible Interpretation des ?effective control? Test werden auch behandelt. Weiter gibt es verschiedene Meinungen und Interpretationsrichtungen, so bei-spielsweise die Frage nach einer de facto Organschaft der Armee der Republik Srpska (VRS) und einer damit verbundenen ?ultra vires? Haftbarkeit der Republik Jugoslawien. Im letzten Kapitel geht es um die Frage, ob mittels des Kriteriums der ?effektiven Kontrolle?, geprägt durch eine derart große Abhängigkeit der VRS von der Republik Jugoslawien und der damit möglichen Ausübung von Kontrolle, eine de facto Organschaft der VRS festgestellt werden kann.AbstractThe intervention of third party states in non-international armed conflictIn my diploma thesis I am trying to answer the following question: when does a non-international armed conflict get internationalized by the intervention of a third party state. Starting with an introduction I am presenting my chosen method International Law and International Relations (IL/IR). Each work using this method is based on a model or a diagnostics out of practice. The main structure of problems is shown precisely therefore common problems can be identified much easier. In the first chapter I want to present a definition of the term armed conflict, international as well as non-international armed conflict were interpreted in different manners during history. The Nicaragua case is a very important case in my diploma thesis, I compare ?overall control? test and ?effective control? test. The finding of the judgment in the Nicaragua case will also be analyzed.The main part of my diploma thesis is about the Tadic case. It is the starting point of the scientific discussion about the internationalization of non-international armed conflicts. The ?effective control? test as well as ?overall control? test and the International Criminal Tribunal for the former Yugoslavia?s own critic and a flexible interpretation of the ?effective control? test are analyzed. There are several opinions and ways of interpretation for instance a de facto affiliation of the army of the Republic Srpska (VRS) and a possible ?ultra vires? liability to the Federal Republic of Yugoslavia. In the last chapter I am dealing with the question whether it is possible to determine a de facto affiliation of the army of the Republic Srpska with the criteria of ?effective control? in con-nection with an essential dependency of the army of the Republic Srpska to the Federal Republic of Yugoslavia and the possibility of exercising control.Albin SkasaAbweichender Titel laut Übersetzung der Verfasserin/des VerfassersGraz, Univ., Dipl.-Arb., 2010(VLID)21127