Open Access. Powered by Scholars. Published by Universities.®

Medicine and Health Sciences Commons

Open Access. Powered by Scholars. Published by Universities.®

Journal Articles

Biological

Internal Medicine

Articles 1 - 8 of 8

Full-Text Articles in Medicine and Health Sciences

Cellular Dynamic Simulator: An Event Driven Molecular Simulation Environment For Cellular Physiology, Michael J Byrne, M Neal Waxham, Yoshihisa Kubota Jun 2010

Cellular Dynamic Simulator: An Event Driven Molecular Simulation Environment For Cellular Physiology, Michael J Byrne, M Neal Waxham, Yoshihisa Kubota

Journal Articles

In this paper, we present the Cellular Dynamic Simulator (CDS) for simulating diffusion and chemical reactions within crowded molecular environments. CDS is based on a novel event driven algorithm specifically designed for precise calculation of the timing of collisions, reactions and other events for each individual molecule in the environment. Generic mesh based compartments allow the creation / importation of very simple or detailed cellular structures that exist in a 3D environment. Multiple levels of compartments and static obstacles can be used to create a dense environment to mimic cellular boundaries and the intracellular space. The CDS algorithm takes into …


Structural Plasticity Can Produce Metaplasticity, Georgios Kalantzis, Harel Z Shouval Jan 2009

Structural Plasticity Can Produce Metaplasticity, Georgios Kalantzis, Harel Z Shouval

Journal Articles

BACKGROUND: Synaptic plasticity underlies many aspect of learning memory and development. The properties of synaptic plasticity can change as a function of previous plasticity and previous activation of synapses, a phenomenon called metaplasticity. Synaptic plasticity not only changes the functional connectivity between neurons but in some cases produces a structural change in synaptic spines; a change thought to form a basis for this observed plasticity. Here we examine to what extent structural plasticity of spines can be a cause for metaplasticity. This study is motivated by the observation that structural changes in spines are likely to affect the calcium dynamics …


Rationale For Reading Fluconazole Mics At 24 Hours Rather Than 48 Hours When Testing Candida Spp By The Clsi M27-A2 Standard Method, Luis Ostrosky-Zeichner, John H Rex, Michael A Pfaller, Daniel J Diekema, Barbara D Alexander, David Andes, Steven D Brown, Vishnu Chaturvedi, Mahmoud A Ghannoum, Cindy C Knapp, Daniel J Sheehan, Thomas J Walsh Nov 2008

Rationale For Reading Fluconazole Mics At 24 Hours Rather Than 48 Hours When Testing Candida Spp By The Clsi M27-A2 Standard Method, Luis Ostrosky-Zeichner, John H Rex, Michael A Pfaller, Daniel J Diekema, Barbara D Alexander, David Andes, Steven D Brown, Vishnu Chaturvedi, Mahmoud A Ghannoum, Cindy C Knapp, Daniel J Sheehan, Thomas J Walsh

Journal Articles

We investigated if CLSI M27-A2 Candida species breakpoints for fluconazole MIC are valid when read at 24 h. Analysis of a data set showed good correlation between 48- and 24-h MICs, as well as similar outcomes and pharmacodynamic efficacy parameters, except for isolates in the susceptible dose-dependent category, such as Candida glabrata.


Poly(A)-Binding Protein-Interacting Protein 1 Binds To Eukaryotic Translation Initiation Factor 3 To Stimulate Translation, Yvan Martineau, Mélanie C Derry, Xiaoshan Wang, Akiko Yanagiya, Juan José Berlanga, Ann-Bin Shyu, Hiroaki Imataka, Kalle Gehring, Nahum Sonenberg Nov 2008

Poly(A)-Binding Protein-Interacting Protein 1 Binds To Eukaryotic Translation Initiation Factor 3 To Stimulate Translation, Yvan Martineau, Mélanie C Derry, Xiaoshan Wang, Akiko Yanagiya, Juan José Berlanga, Ann-Bin Shyu, Hiroaki Imataka, Kalle Gehring, Nahum Sonenberg

Journal Articles

Poly(A)-binding protein (PABP) stimulates translation initiation by binding simultaneously to the mRNA poly(A) tail and eukaryotic translation initiation factor 4G (eIF4G). PABP activity is regulated by PABP-interacting (Paip) proteins. Paip1 binds PABP and stimulates translation by an unknown mechanism. Here, we describe the interaction between Paip1 and eIF3, which is direct, RNA independent, and mediated via the eIF3g (p44) subunit. Stimulation of translation by Paip1 in vivo was decreased upon deletion of the N-terminal sequence containing the eIF3-binding domain and upon silencing of PABP or several eIF3 subunits. We also show the formation of ternary complexes composed of Paip1-PABP-eIF4G and …


Activation Of Heat Shock And Antioxidant Responses By The Natural Product Celastrol: Transcriptional Signatures Of A Thiol-Targeted Molecule, Amy Trott, James D West, Lada Klaić, Sandy D Westerheide, Richard B Silverman, Richard I Morimoto, Kevin A Morano Mar 2008

Activation Of Heat Shock And Antioxidant Responses By The Natural Product Celastrol: Transcriptional Signatures Of A Thiol-Targeted Molecule, Amy Trott, James D West, Lada Klaić, Sandy D Westerheide, Richard B Silverman, Richard I Morimoto, Kevin A Morano

Journal Articles

Stress response pathways allow cells to sense and respond to environmental changes and adverse pathophysiological states. Pharmacological modulation of cellular stress pathways has implications in the treatment of human diseases, including neurodegenerative disorders, cardiovascular disease, and cancer. The quinone methide triterpene celastrol, derived from a traditional Chinese medicinal herb, has numerous pharmacological properties, and it is a potent activator of the mammalian heat shock transcription factor HSF1. However, its mode of action and spectrum of cellular targets are poorly understood. We show here that celastrol activates Hsf1 in Saccharomyces cerevisiae at a similar effective concentration seen in mammalian cells. Transcriptional …


Dynamics Of A Minimal Model Of Interlocked Positive And Negative Feedback Loops Of Transcriptional Regulation By Camp-Response Element Binding Proteins, Hao Song, Paul Smolen, Evyatar Av-Ron, Douglas A Baxter, John H Byrne May 2007

Dynamics Of A Minimal Model Of Interlocked Positive And Negative Feedback Loops Of Transcriptional Regulation By Camp-Response Element Binding Proteins, Hao Song, Paul Smolen, Evyatar Av-Ron, Douglas A Baxter, John H Byrne

Journal Articles

cAMP-response element binding (CREB) proteins are involved in transcriptional regulation in a number of cellular processes (e.g., neural plasticity and circadian rhythms). The CREB family contains activators and repressors that may interact through positive and negative feedback loops. These loops can be generated by auto- and cross-regulation of expression of CREB proteins, via CRE elements in or near their genes. Experiments suggest that such feedback loops may operate in several systems (e.g., Aplysia and rat). To understand the functional implications of such feedback loops, which are interlocked via cross-regulation of transcription, a minimal model with a positive and negative loop …


Expression Of The Neural Stem Cell Markers Ng2 And L1 In Human Angiomyolipoma: Are Angiomyolipomas Neoplasms Of Stem Cells?, So Dug Lim, William Stallcup, Benjamin Lefkove, Baskaran Govindarajan, Kit Sing Au, Hope Northrup, Deborah Lang, David E Fisher, Avani Patel, Mahul B Amin, Jack L Arbiser Mar 2007

Expression Of The Neural Stem Cell Markers Ng2 And L1 In Human Angiomyolipoma: Are Angiomyolipomas Neoplasms Of Stem Cells?, So Dug Lim, William Stallcup, Benjamin Lefkove, Baskaran Govindarajan, Kit Sing Au, Hope Northrup, Deborah Lang, David E Fisher, Avani Patel, Mahul B Amin, Jack L Arbiser

Journal Articles

Angiomyolipomas are benign tumors of the kidney which express phenotypes of smooth muscle, fat, and melanocytes. These tumors appear with increased frequency in the autosomal dominant disorder tuberous sclerosis and are the leading cause of morbidity in adults with tuberous sclerosis. While benign, these tumors are capable of provoking life threatening hemorrhage and replacement of the kidney parenchyma, resulting in renal failure. The histogenesis of these tumors is currently unclear, although currently, we believe these tumors arise from "perivascular epithelioid cells" of which no normal counterpart has been convincingly demonstrated. Recently, stem cell precursors have been recognized that can give …


Cart: An Hrs/Actinin-4/Berp/Myosin V Protein Complex Required For Efficient Receptor Recycling, Qing Yan, Wei Sun, Pekka Kujala, Yasmin Lotfi, Thomas A Vida, Andrew J Bean May 2005

Cart: An Hrs/Actinin-4/Berp/Myosin V Protein Complex Required For Efficient Receptor Recycling, Qing Yan, Wei Sun, Pekka Kujala, Yasmin Lotfi, Thomas A Vida, Andrew J Bean

Journal Articles

Altering the number of surface receptors can rapidly modulate cellular responses to extracellular signals. Some receptors, like the transferrin receptor (TfR), are constitutively internalized and recycled to the plasma membrane. Other receptors, like the epidermal growth factor receptor (EGFR), are internalized after ligand binding and then ultimately degraded in the lysosome. Routing internalized receptors to different destinations suggests that distinct molecular mechanisms may direct their movement. Here, we report that the endosome-associated protein hrs is a subunit of a protein complex containing actinin-4, BERP, and myosin V that is necessary for efficient TfR recycling but not for EGFR degradation. The …