Biopacemaker acceleration without increased synchronization by chronic exposure to phorbol myristate acetate

L'activité électrique du coeur est initiée par la génération spontanée de potentiels d'action venant des cellules pacemaker du noeud sinusal (SN). Toute dysfonction au niveau de cette région entraîne une instabilité électrique du coeur. La majorité des patients souffrant d'un noeud sinusal déficient nécessitent l'implantation chirurgicale d'un pacemaker électronique; cependant, les limitations de cette approche incitent à la recherche d'une alternative thérapeutique. La base moléculaire des courants ioniques jouant un rôle crucial dans l'activité du noeud sinusal sont de plus en plus connues. Une composante importante de l'activité des cellules pacemakers semble être le canal HCN, responsable du courant pacemaker If. Le facteur T-box 3 (Tbx3), un facteur de transcription conservé durant le processus de l'évolution, est nécessaire au développement du système de conduction cardiaque. De précédentes études ont démontré que dans différentes lignées cellulaires le Phorbol 12-myristate 13-acetate (PMA) active l'expression du gène codant Tbx3 via des réactions en cascade partant de la protéine kinase C (PKC). L'objectif principal de cette étude est de tester si le PMA peut augmenter la fréquence et la synchronisation de l'activité spontanée du pacemaker biologique en culture. Plus précisément, nous avons étudié les effets de l'exposition chronique au PMA sur l'expression du facteur de transcription Tbx3, sur HCN4 et l'activité spontanée chez des monocouches de culture de myocytes ventriculaires de rats néonataux (MVRN). Nos résultats démontrent que le PMA augmente significativement le facteur transcription de Tbx3 et l'expression ARNm de HCN4, favorisant ainsi l'augmentation du rythme et de la stabilité de l'activité autonome. De plus, une diminution significative de la vitesse de conduction a été relevée et est attribuée à la diminution du couplage intercellulaire. La diminution de la vitesse de conduction pourrait expliquer l'effet négatif du PMA sur la synchronisation de l'activité autonome du pacemaker biologique. Ces résultats ont été confirmés par un modèle mathématique multicellulaire suggérant que des fréquences et résistances intercellulaires plus élevée pourraient induire une activité plus stable et moins synchrone. Cette étude amène de nouvelles connaissances très importantes destinées à la production d'un pacemaker biologique efficient et robuste.

The European Union’s Response to Piracy: Are the Lessons Learned in the Horn of Africa a Model for the Gulf of Guinea? EU Diplomacy Paper/2015

The European Union (EU) is seen as the leading actor in successfully fighting piracy around the Horn of Africa. As a global trade power with strong economic interests, the EU is also challenged by similar maritime security threats in the Gulf of Guinea. To date, there has been no comprehensive analysis to assess the potential transfer of successful EU instruments from the Horn of Africa to the piracy situation in West African waters. This paper examines to what extent the EU can draw on its experience made in the Horn of Africa to deter piracy in West African waters. Based on qualitative research interviews, lessons learned from East Africa are identified and subsequently applied to the situation in the Gulf of Guinea. The results show that the EU is only partially drawing on its experience made in the Horn of Africa. One the one hand, it is rather reluctant to use crisis management instruments such as naval operations. On the other hand, the EU is drawing on its successful leadership in international political and military cooperation from around the Horn of Africa in order to make more effective use of available resources in the Gulf of Guinea.

Key to League of Nations documents placed on public sale, 1920-1929 /

Kept up to date by supplements, 1930-1934/36.

LPF Farm Security Administration.7; Farm Security Administration

No caption or date. Photo by Marion Post. Gift of M. Feingold.

LPF United States Dept. of Agriculture.69; United States Dept. of Agriculture

Mexican farm workers playing in a band at a Farm Labor Supply Center. No date or location given. Gift of M. Feingold.

LPF Detroit House of Corrections.1; Detroit House of Corrections

DeHoCo demonstration, no date. Photo by Ken Fireman. Fifth Estate photo

Manual of recommended practice for railway engineering: definitions of terms, designs and plans, specifications, economics of construction and maintenance [and] principles and practices. Complete to March 24, 1976.

Kept up-to-date by periodic replacement or new pages. The latest supplements have title: Manual for railway engineering (fixed properties)

Appletons' general guide to the United States and Canada.

Issue for 1893 has an appendix describing the Columbian exposition; those for 1899-1901, a short account of Puerto Rico, Cuba, Hawaii, and the Philippines.

A Resource guide to Chicago cultural institutions.

"Assistance provided by Terra Foundation for the Arts."

Fossil fuel-fired power plants : report to the House and Senate Environment and Energy Commissions.

The Illinois Environmental Protection Agency (Illinois EPA) was asked by the Illinois General Assembly to examine whether the State should address further potential restrictions on power plant pollution. This request was made under Section 9-10 of the Environmental Protection Act (Act). This is a report of the Illinois EPA's findings. The Illinois EPA has prepared this report of its findings to date based on consideration of a broad spectrum of issues including health benefits, the impact of the reliability of the power grid, the impact on consumer utility rates and the impact on jobs and Illinois' economy. It provides an overview of the principal issues, presents a review of the information we have gathered that addresses those issues, lists information gaps, and uncertainties and finally, lists the work that remains to develop a solution that does not create unintended adverse economic consequences for the people of Illinois.

A register of ships, employed in the service of the Honorable the United East India Company, from the year 1760 to 1810 : with an appendix, containing a variety of particulars, and useful information interesting to those concerned with East India commerce /

Goldsmiths'-Kress no. 20268.7.

A collection of all such acts of the General Assembly of Virginia, of a public and permanent nature, as are now in force : with a new and complete index : to which are prefixed the declaration of rights, and constitution, or form of government...

Kept up to date by supplements.

How to become a successful stenograher, for the young woman who wants to make good ...

"Acknowledgment is due Miss Eleanor Gilbert for her co-operation in the preparation of this little book, and permission to use some of her newspaper editorials for business women."

History of the Heatwole family from the beginning of the seventeenth century to the present time (1907)

The Germans in the United States. By Rudolf Cronau: p. 19-61.

A guide to the West Indies, Bermuda and Panama /

Plates printed on both sides.