Open Access. Powered by Scholars. Published by Universities.®
Articles 1 - 2 of 2
Full-Text Articles in Endocrine System Diseases
Pka-Mediated Erk1/2 Inactivation And Hsp70 Gene Expression Following Exercise, C.W. Melling, Matthew Krause, Earl Noble
Pka-Mediated Erk1/2 Inactivation And Hsp70 Gene Expression Following Exercise, C.W. Melling, Matthew Krause, Earl Noble
Jamie Melling
Exercise induces the expression of the cardioprotective protein, Hsp70, through the activation of its transcription factor HSF1. Recently, we reported that administration of a protein kinase A (PKA) inhibitor suppressed exercise-induced hsp70 gene expression, suggesting a role for PKA in the regulation of HSF1 activation in vivo. While the mechanism by which PKA regulates HSF1 is unclear, studies in vitro have reported that HSF1 is phosphorylated on two serine residues by mitogen activated protein kinases (MAPKs); ERK1/2 (ser307) and JNK/SAPK (ser363). As PKA is a regulator of these protein kinases, the current study examined the role of PKA in their …
Imaging Islets Labeled Wth Magnetic Nanoparticules At 1.5 Tesla, J.H. Tai, Paula Foster, Alma Rosales, Biao Feng, Craig Ha, Violetta Martinez, Soha Ramadan, Jonatan Snir, C.W. Melling, Savita Dhanvantari, Brian Rutt, David White
Imaging Islets Labeled Wth Magnetic Nanoparticules At 1.5 Tesla, J.H. Tai, Paula Foster, Alma Rosales, Biao Feng, Craig Ha, Violetta Martinez, Soha Ramadan, Jonatan Snir, C.W. Melling, Savita Dhanvantari, Brian Rutt, David White
Jamie Melling
We have developed a magnetic resonance imaging (MRI) technique for imaging Feridex (superparamagnetic iron oxide [SPIO])-labeled islets of Langerhans using a standard clinical 1.5-Tesla (T) scanner and employing steady-state acquisition imaging sequence (3DFIESTA). Both porcine and rat islets were labeled with SPIO by a transfection technique using a combination of poly-l-lysine and electroporation. Electron microscopy demonstrated presence of SPIO particles within the individual islet cells, including beta-cells and particles trapped between cell membranes. Our labeling method produced a transfection rate of 860 pg to 3.4 ng iron per islet, dependent on the size of the islet. The labeling procedure did …