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Humans

2012

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Articles 1 - 30 of 88

Full-Text Articles in Life Sciences

Persistence Of Episomal Hiv-1 Infection Intermediates In Patients On Highly Active Anti-Retroviral Therapy, Mark Sharkey, Ian Teo, Thomas Greenough, Natalia Sharova, Katherine Luzuriaga, John Sullivan, R. Bucy, Leondios Kostrikis, Ashley Haase, Claire Veryard, Raul Davaro, Sarah Cheeseman, Jennifer Daly, Carol Bova, Richard Ellison, Brian Mady, Kwan Lai, Graeme Moyle, Mark Nelson, Brian Gazzard, Sunil Shaunak, Mario Stevenson Dec 2012

Persistence Of Episomal Hiv-1 Infection Intermediates In Patients On Highly Active Anti-Retroviral Therapy, Mark Sharkey, Ian Teo, Thomas Greenough, Natalia Sharova, Katherine Luzuriaga, John Sullivan, R. Bucy, Leondios Kostrikis, Ashley Haase, Claire Veryard, Raul Davaro, Sarah Cheeseman, Jennifer Daly, Carol Bova, Richard Ellison, Brian Mady, Kwan Lai, Graeme Moyle, Mark Nelson, Brian Gazzard, Sunil Shaunak, Mario Stevenson

Associate Professor Mark Nelson

Treatment of HIV-1-infected individuals with a combination of anti-retroviral agents results in sustained suppression of HIV-1 replication, as evidenced by a reduction in plasma viral RNA to levels below the limit of detection of available assays. However, even in patients whose plasma viral RNA levels have been suppressed to below detectable levels for up to 30 months, replication-competent virus can routinely be recovered from patient peripheral blood mononuclear cells and from semen. A reservoir of latently infected cells established early in infection may be involved in the maintenance of viral persistence despite highly active anti-retroviral therapy. However, whether virus replication …


Vegf And Angiopoietin-1 Exert Opposing Effects On Cell Junctions By Regulating The Rho Gef Syx, Siu P. Ngok, Rory Geyer, Miaoliang Liu, Antonis Kourtidis, Sudesh Agrawal, Chuanshen Wu, Himabindu Reddy Seerapu, Laura J. Lewis-Tuffin, Karen L. Moodie, Deborah Huveldt, Ruth Marx, Jay M. Baraban, Peter Storz, Arie Horowitz, Panos Z. Anastasiadis Dec 2012

Vegf And Angiopoietin-1 Exert Opposing Effects On Cell Junctions By Regulating The Rho Gef Syx, Siu P. Ngok, Rory Geyer, Miaoliang Liu, Antonis Kourtidis, Sudesh Agrawal, Chuanshen Wu, Himabindu Reddy Seerapu, Laura J. Lewis-Tuffin, Karen L. Moodie, Deborah Huveldt, Ruth Marx, Jay M. Baraban, Peter Storz, Arie Horowitz, Panos Z. Anastasiadis

Dartmouth Scholarship

Vascular endothelial growth factor (VEGF) and Ang1 (Angiopoietin-1) have opposing effects on vascular permeability, but the molecular basis of these effects is not fully known. We report in this paper that VEGF and Ang1 regulate endothelial cell (EC) junctions by determining the localization of the RhoA-specific guanine nucleotide exchange factor Syx. Syx was recruited to junctions by members of the Crumbs polarity complex and promoted junction integrity by activating Diaphanous. VEGF caused translocation of Syx from cell junctions, promoting junction disassembly, whereas Ang1 maintained Syx at the junctions, inducing junction stabilization. The VEGF-induced translocation of Syx from EC junctions was …


Targeted Mutation Of Mouse Skeletal Muscle Sodium Channel Produces Myotonia And Potassium-Sensitive Weakness, Lawrence Hayward, Joanna Kim, Ming-Yang Lee, Hongru Zhou, Ji Kim, Kumudini Misra, Mohammad Salajegheh, Fen-Fen Wu, Shinji Matsuda, Valerie Reid, Didier Cros, Eric Hoffman, Jean-Marc Renaud, Stephen Cannon, Robert Brown Dec 2012

Targeted Mutation Of Mouse Skeletal Muscle Sodium Channel Produces Myotonia And Potassium-Sensitive Weakness, Lawrence Hayward, Joanna Kim, Ming-Yang Lee, Hongru Zhou, Ji Kim, Kumudini Misra, Mohammad Salajegheh, Fen-Fen Wu, Shinji Matsuda, Valerie Reid, Didier Cros, Eric Hoffman, Jean-Marc Renaud, Stephen Cannon, Robert Brown

Dr Robert Brown

Hyperkalemic periodic paralysis (HyperKPP) produces myotonia and attacks of muscle weakness triggered by rest after exercise or by K+ ingestion. We introduced a missense substitution corresponding to a human familial HyperKPP mutation (Met1592Val) into the mouse gene encoding the skeletal muscle voltage-gated Na+ channel NaV1.4. Mice heterozygous for this mutation exhibited prominent myotonia at rest and muscle fiber-type switching to a more oxidative phenotype compared with controls. Isolated mutant extensor digitorum longus muscles were abnormally sensitive to the Na+/K+ pump inhibitor ouabain and exhibited age-dependent changes, including delayed relaxation and altered generation of tetanic force. Moreover, rapid and sustained weakness …


Decreased Metallation And Activity In Subsets Of Mutant Superoxide Dismutases Associated With Familial Amyotrophic Lateral Sclerosis, Lawrence Hayward, Jorge Rodriguez, Ji Kim, Ashutosh Tiwari, Joy Goto, Diane Cabelli, Joan Valentine, Robert Brown Dec 2012

Decreased Metallation And Activity In Subsets Of Mutant Superoxide Dismutases Associated With Familial Amyotrophic Lateral Sclerosis, Lawrence Hayward, Jorge Rodriguez, Ji Kim, Ashutosh Tiwari, Joy Goto, Diane Cabelli, Joan Valentine, Robert Brown

Dr Robert Brown

Over 90 different mutations in the gene encoding copper/zinc superoxide dismutase (SOD1) cause approximately 2% of amyotrophic lateral sclerosis (ALS) cases by an unknown mechanism. We engineered 14 different human ALS-related SOD1 mutants and obtained high yields of biologically metallated proteins from an Sf21 insect cell expression system. Both the wild type and mutant "as isolated" SOD1 variants were deficient in copper and were heterogeneous by native gel electrophoresis. By contrast, although three mutant SOD1s with substitutions near the metal binding sites (H46R, G85R, and D124V) were severely deficient in both copper and zinc ions, zinc deficiency was not a …


Adenosine Deaminase Enhances The Immunogenicity Of Human Dendritic Cells From Healthy And Hiv-Infected Individuals, Víctor Casanova, Isaac Isaac Naval-Macabuhay, Marta Massanella, Marta Rodríguez-García Dec 2012

Adenosine Deaminase Enhances The Immunogenicity Of Human Dendritic Cells From Healthy And Hiv-Infected Individuals, Víctor Casanova, Isaac Isaac Naval-Macabuhay, Marta Massanella, Marta Rodríguez-García

Dartmouth Scholarship

ADA is an enzyme implicated in purine metabolism, and is critical to ensure normal immune function. Its congenital deficit leads to severe combined immunodeficiency (SCID). ADA binding to adenosine receptors on dendritic cell surface enables T-cell costimulation through CD26 crosslinking, which enhances T-cell activation and proliferation. Despite a large body of work on the actions of the ecto-enzyme ADA on T-cell activation, questions arise on whether ADA can also modulate dendritic cell maturation. To this end we investigated the effects of ADA on human monocyte derived dendritic cell biology. Our results show that both the enzymatic and non-enzymatic activities of …


A Hunter Virus That Targets Both Infected Cells And Hiv Free Virions: Implications For Therapy, Cody Greer, Gisela García-Ramos Dec 2012

A Hunter Virus That Targets Both Infected Cells And Hiv Free Virions: Implications For Therapy, Cody Greer, Gisela García-Ramos

Biology Faculty Publications

The design of 'hunter' viruses aimed at destroying human immunodeficiency virus (HIV) infected cells is an active area of research that has produced promising results in vitro. Hunters are designed to target exposed viral envelope proteins in the membranes of infected cells, but there is evidence that the hunter may also target envelope proteins of free HIV, inducing virus-virus fusion. In order to predict the effects of this fusion on therapy outcomes and determine whether fusion ability is advantageous for hunter virus design, we have constructed a model to account for the possibility of hunter-HIV fusion. The study was based …


Process And Domain Specificity In Regions Engaged For Face Processing: An Fmri Study Of Perceptual Differentiation, Heather R. Collins, Xun Zhu, Ramesh S. Bhatt, Jonathan D. Clark, Jane E. Joseph Dec 2012

Process And Domain Specificity In Regions Engaged For Face Processing: An Fmri Study Of Perceptual Differentiation, Heather R. Collins, Xun Zhu, Ramesh S. Bhatt, Jonathan D. Clark, Jane E. Joseph

Psychology Faculty Publications

The degree to which face-specific brain regions are specialized for different kinds of perceptual processing is debated. This study parametrically varied demands on featural, first-order configural, or second-order configural processing of faces and houses in a perceptual matching task to determine the extent to which the process of perceptual differentiation was selective for faces regardless of processing type (domain-specific account), specialized for specific types of perceptual processing regardless of category (process-specific account), engaged in category-optimized processing (i.e., configural face processing or featural house processing), or reflected generalized perceptual differentiation (i.e., differentiation that crosses category and processing type boundaries). ROIs were …


Immunological Mechanisms Of Extracorporeal Photopheresis In Cutaneous T Cell Lymphoma And Graft Versus Host Disease, Lisa Shiue Dec 2012

Immunological Mechanisms Of Extracorporeal Photopheresis In Cutaneous T Cell Lymphoma And Graft Versus Host Disease, Lisa Shiue

Dissertations & Theses (Open Access)

IMMUNOLOGICAL MECHANISMS OF EXTRACORPOREAL PHOTOPHERESIS IN CUTANEOUS T CELL LYMPHOMA AND GRAFT VERSUS HOST DISEASE

Publication No.___________

Lisa Harn-Ging Shiue, B.S.

Supervisory Professor: Madeleine Duvic, M.D.

Extracorporeal photopheresis (ECP) is an effective, low-risk immunomodulating therapy for leukemic cutaneous T cell lymphoma (L-CTCL) and graft versus host disease (GVHD), but whether the mechanism(s) of action in these two diseases is (are) identical or different is unclear. To determine the effects of ECP in vivo, we studied regulatory T cells (T-regs), cytotoxic T lymphocytes (CTLs), and dendritic cells (DCs) by immunofluorescence flow cytometry in 18 L-CTCL and 11 GVHD patients before …


Plant Polyadenylation Factors: Conservation And Variety In The Polyadenylation Complex In Plants, Arthur G. Hunt, Denghui Xing, Qingshun Q. Li Nov 2012

Plant Polyadenylation Factors: Conservation And Variety In The Polyadenylation Complex In Plants, Arthur G. Hunt, Denghui Xing, Qingshun Q. Li

Plant and Soil Sciences Faculty Publications

BACKGROUND: Polyadenylation, an essential step in eukaryotic gene expression, requires both cis-elements and a plethora of trans-acting polyadenylation factors. The polyadenylation factors are largely conserved across mammals and fungi. The conservation seems also extended to plants based on the analyses of Arabidopsis polyadenylation factors. To extend this observation, we systemically identified the orthologs of yeast and human polyadenylation factors from 10 plant species chosen based on both the availability of their genome sequences and their positions in the evolutionary tree, which render them representatives of different plant lineages.

RESULTS: The evolutionary trajectories revealed several interesting features of plant polyadenylation factors. …


A Novel Method For Comparative Analysis Of Retinal Specialization Traits From Topographic Maps, Bret A. Moore, Jason M. Kamilar, Shaun P. Collin, Olaf R. P. Bininda-Emonds, Nathaniel J. Dominy, Margaret I. Hall, Christopher P. Hessy, Sonke Johnsen, Thomas J. Lisney, Ellis R. Loew, Gillian Moritz Nov 2012

A Novel Method For Comparative Analysis Of Retinal Specialization Traits From Topographic Maps, Bret A. Moore, Jason M. Kamilar, Shaun P. Collin, Olaf R. P. Bininda-Emonds, Nathaniel J. Dominy, Margaret I. Hall, Christopher P. Hessy, Sonke Johnsen, Thomas J. Lisney, Ellis R. Loew, Gillian Moritz

Dartmouth Scholarship

Abstract Vertebrates possess different types of retinal specializations that vary in number, size, shape, and position in the retina. This diversity in retinal configuration has been revealed through topographic maps, which show variations in neuron density across the retina. Although topographic maps of about 300 vertebrates are available, there is no method for characterizing retinal traits quantitatively. Our goal is to present a novel method to standardize information on the position of the retinal specializations and changes in retinal ganglion cell (RGC) density across the retina from published topographic maps. We measured the position of the retinal specialization using two …


Inla Promotes Dissemination Of Listeria Monocytogenes To The Mesenteric Lymph Nodes During Food Borne Infection Of Mice, Elsa N. Bou Ghanem, Grant S. Jones, Tanya Myers-Morales, Pooja D. Patil, Achmad N. Hidayatullah, Sarah E. F. D'Orazio Nov 2012

Inla Promotes Dissemination Of Listeria Monocytogenes To The Mesenteric Lymph Nodes During Food Borne Infection Of Mice, Elsa N. Bou Ghanem, Grant S. Jones, Tanya Myers-Morales, Pooja D. Patil, Achmad N. Hidayatullah, Sarah E. F. D'Orazio

Microbiology, Immunology, and Molecular Genetics Faculty Publications

Intestinal Listeria monocytogenes infection is not efficient in mice and this has been attributed to a low affinity interaction between the bacterial surface protein InlA and E-cadherin on murine intestinal epithelial cells. Previous studies using either transgenic mice expressing human E-cadherin or mouse-adapted L. monocytogenes expressing a modified InlA protein (InlA(m)) with high affinity for murine E-cadherin showed increased efficiency of intragastric infection. However, the large inocula used in these studies disseminated to the spleen and liver rapidly, resulting in a lethal systemic infection that made it difficult to define the natural course of intestinal infection. We describe here a …


Controls Of Nucleosome Positioning In The Human Genome, Daniel J. Gaffney, Graham Mcvicker, Athma A. Pai, Yvonne N. Fondufe-Mittendorf, Noah Lewellen, Katelyn Michelini, Jonathan Widom, Yoav Gilad, Jonathan K. Pritchard Nov 2012

Controls Of Nucleosome Positioning In The Human Genome, Daniel J. Gaffney, Graham Mcvicker, Athma A. Pai, Yvonne N. Fondufe-Mittendorf, Noah Lewellen, Katelyn Michelini, Jonathan Widom, Yoav Gilad, Jonathan K. Pritchard

Molecular and Cellular Biochemistry Faculty Publications

Nucleosomes are important for gene regulation because their arrangement on the genome can control which proteins bind to DNA. Currently, few human nucleosomes are thought to be consistently positioned across cells; however, this has been difficult to assess due to the limited resolution of existing data. We performed paired-end sequencing of micrococcal nuclease-digested chromatin (MNase-seq) from seven lymphoblastoid cell lines and mapped over 3.6 billion MNase-seq fragments to the human genome to create the highest-resolution map of nucleosome occupancy to date in a human cell type. In contrast to previous results, we find that most nucleosomes have more consistent positioning …


Wolbachia Strain Wpip Yields A Pattern Of Cytoplasmic Incompatibility Enhancing A Wolbachia-Based Suppression Strategy Against The Disease Vector Aedes Albopictus, Maurizio Calvitti, Riccardo Moretti, Amanda R. Skidmore, Stephen L. Dobson Nov 2012

Wolbachia Strain Wpip Yields A Pattern Of Cytoplasmic Incompatibility Enhancing A Wolbachia-Based Suppression Strategy Against The Disease Vector Aedes Albopictus, Maurizio Calvitti, Riccardo Moretti, Amanda R. Skidmore, Stephen L. Dobson

Entomology Faculty Publications

BACKGROUND: Cytoplasmic incompatibility (CI) is induced in nature by Wolbachia bacteria, resulting in conditional male sterility. Previous research demonstrated that the two Wolbachia strains (wAlbA and wAlbB) that naturally co-infect the disease vector mosquito Aedes albopictus (Asian tiger mosquito) can be replaced with the wPip Wolbachia strain from Culex pipiens. Since Wolbachia-based vector control strategies depend upon the strength and consistency of CI, a greater understanding is needed on the CI relationships between wPip, wAlbA and wAlbB Wolbachia in Ae. albopictus.

METHODS: This work consisted of a collaborative series of crosses carried out in Italy and in US to study …


Molecular Mechanism For Depolarization-Induced Modulation Of Kv Channel Closure, Alain J. Labro, Jerome J. Lacroix, Carlos A. Villalba-Galea, Dirk J. Snyders, Francisco Bezanilla Nov 2012

Molecular Mechanism For Depolarization-Induced Modulation Of Kv Channel Closure, Alain J. Labro, Jerome J. Lacroix, Carlos A. Villalba-Galea, Dirk J. Snyders, Francisco Bezanilla

School of Pharmacy Faculty Articles

Voltage-dependent potassium (Kv) channels provide the repolarizing power that shapes the action potential duration and helps control the firing frequency of neurons. The K(+) permeation through the channel pore is controlled by an intracellularly located bundle-crossing (BC) gate that communicates with the voltage-sensing domains (VSDs). During prolonged membrane depolarizations, most Kv channels display C-type inactivation that halts K(+) conduction through constriction of the K(+) selectivity filter. Besides triggering C-type inactivation, we show that in Shaker and Kv1.2 channels (expressed in Xenopus laevis oocytes), prolonged membrane depolarizations also slow down the kinetics of VSD deactivation and BC gate closure during the …


A Human Phospholipid Phosphatase Activated By A Transmembrane Control Module, Christian R. Halaszovich, Michael G. Leitner, Angeliki Mavrantoni, Audrey Le, Ludivine Frezza, Anja Feuer, Daniela N. Schreiber, Carlos A. Villalba-Galea, Dominik Oliver Nov 2012

A Human Phospholipid Phosphatase Activated By A Transmembrane Control Module, Christian R. Halaszovich, Michael G. Leitner, Angeliki Mavrantoni, Audrey Le, Ludivine Frezza, Anja Feuer, Daniela N. Schreiber, Carlos A. Villalba-Galea, Dominik Oliver

School of Pharmacy Faculty Articles

In voltage-sensitive phosphatases (VSPs), a transmembrane voltage sensor domain (VSD) controls an intracellular phosphoinositide phosphatase domain, thereby enabling immediate initiation of intracellular signals by membrane depolarization. The existence of such a mechanism in mammals has remained elusive, despite the presence of VSP-homologous proteins in mammalian cells, in particular in sperm precursor cells. Here we demonstrate activation of a human VSP (hVSP1/TPIP) by an intramolecular switch. By engineering a chimeric hVSP1 with enhanced plasma membrane targeting containing the VSD of a prototypic invertebrate VSP, we show that hVSP1 is a phosphoinositide-5-phosphatase whose predominant substrate is PI(4,5)P(2). In the chimera, enzymatic activity …


Dendritic Cells In Hepatitis C Infection: Can They (Help) Win The Battle, Angela Dolganiuc, Gyongyi Szabo Oct 2012

Dendritic Cells In Hepatitis C Infection: Can They (Help) Win The Battle, Angela Dolganiuc, Gyongyi Szabo

Gyongyi Szabo

Infection with hepatitis C virus (HCV) is a public health problem; it establishes a chronic course in ~85% of infected patients and increases their risk for developing liver cirrhosis, hepatocellular carcinoma, and significant extrahepatic manifestations. The mechanisms of HCV persistence remain elusive and are largely related to inefficient clearance of the virus by the host immune system. Dendritic cells (DCs) are the most efficient inducers of immune responses; they are capable of triggering productive immunity and maintaining the state of tolerance to self- and non-self antigens. During the past decade, multiple research groups have focused on DCs, in hopes of …


Hypoxia And Hypoxia Inducible Factors: Diverse Roles In Liver Diseases, Bharath Nath, Gyongyi Szabo Oct 2012

Hypoxia And Hypoxia Inducible Factors: Diverse Roles In Liver Diseases, Bharath Nath, Gyongyi Szabo

Gyongyi Szabo

Hypoxia has been shown to have a role in the pathogenesis of several forms of liver disease. The hypoxia inducible factors (HIFs) are a family of evolutionarily conserved transcriptional regulators that affect a homeostatic response to low oxygen tension and have been identified as key mediators of angiogenesis, inflammation, and metabolism. In this review we summarize the evidence for a role of HIFs across a range of hepatic pathophysiology. We describe regulation of the HIFs and review investigations that demonstrate a role for HIFs in the development of liver fibrosis, activation of innate immune pathways, hepatocellular carcinoma, as well as …


Mitochondrial Antiviral Signaling Protein Defect Links Impaired Antiviral Response And Liver Injury In Steatohepatitis In Mice, Timea Csak, Angela Dolganiuc, Karen Kodys, Bharath Nath, Jan Petrasek, Shashi Bala, Dora Lippai, Gyongyi Szabo Oct 2012

Mitochondrial Antiviral Signaling Protein Defect Links Impaired Antiviral Response And Liver Injury In Steatohepatitis In Mice, Timea Csak, Angela Dolganiuc, Karen Kodys, Bharath Nath, Jan Petrasek, Shashi Bala, Dora Lippai, Gyongyi Szabo

Gyongyi Szabo

Mitochondrial dysfunction is a pathogenic feature of nonalcoholic steatohepatitis (NASH). NASH complicates hepatotropic viral disease. The mitochondrial antiviral signaling protein (MAVS) is the adapter of helicase receptors involved in sensing double-stranded RNA (dsRNA). We hypothesized that impaired MAVS function may contribute to insufficient antiviral response and liver damage in steatohepatitis. We identified reduced MAVS protein levels and increased MAVS association with the proteasome subunit alpha type 7 (PSMA7) in livers from mice given a methionine-choline-deficient (MCD) diet. Decreased association of MAVS with mitochondria and increased cytosolic cytochrome c indicated mitochondrial damage in steatohepatitis. In vivo administration of the synthetic dsRNA …


An Essential Role For Monocyte Chemoattractant Protein-1 In Alcoholic Liver Injury: Regulation Of Proinflammatory Cytokines And Hepatic Steatosis In Mice, Pranoti Mandrekar, Aditya Ambade, Arlene Lim, Gyongyi Szabo, Donna Catalano Oct 2012

An Essential Role For Monocyte Chemoattractant Protein-1 In Alcoholic Liver Injury: Regulation Of Proinflammatory Cytokines And Hepatic Steatosis In Mice, Pranoti Mandrekar, Aditya Ambade, Arlene Lim, Gyongyi Szabo, Donna Catalano

Gyongyi Szabo

The importance of chemokines in alcoholic liver injury has been implicated. The role of the chemokine, monocyte chemoattractant protein-1 (MCP-1), elevated in patients with alcoholic liver disease is not yet understood. Here, we evaluated the pathophysiological significance of MCP-1 and its receptor, chemokine (C-C motif) receptor 2 (CCR2), in alcoholic liver injury. The Leiber-DeCarli diet containing alcohol or isocaloric control diets were fed to wild-type (WT) and MCP-1-deficient knockout (KO) mice for 6 weeks. In vivo and in vitro assays were performed to study the role of MCP-1 in alcoholic liver injury. MCP-1 was increased in Kupffer cells (KCs) as …


Advanced Molecular Biologic Techniques In Toxicologic Disease, Jeanine Ward, Gyongyi Szabo, David Mcmanus, Edward Boyer Oct 2012

Advanced Molecular Biologic Techniques In Toxicologic Disease, Jeanine Ward, Gyongyi Szabo, David Mcmanus, Edward Boyer

Gyongyi Szabo

The advancement of molecular biologic techniques and their capabilities to answer questions pertaining to mechanisms of pathophysiologic events have greatly expanded over the past few years. In particular, these opportunities have provided researchers and clinicians alike the framework from with which to answer clinical questions not amenable for elucidation using previous, more antiquated methods. Utilizing extremely small molecules, namely microRNA, DNA, protein, and nanoparticles, we discuss the background and utility of these approaches to the progressive, practicing physician. Finally, we consider the application of these tools employed as future bedside point of care tests, aiding in the ultimate goal of …


Novel Developmental Biology-Based Protocol Of Embryonic Stem Cell Differentiation To Morphologically Sound And Functional Yet Immature Hepatocytes, Terence Bukong, Tracie Lo, Gyongyi Szabo, Angela Dolganiuc Oct 2012

Novel Developmental Biology-Based Protocol Of Embryonic Stem Cell Differentiation To Morphologically Sound And Functional Yet Immature Hepatocytes, Terence Bukong, Tracie Lo, Gyongyi Szabo, Angela Dolganiuc

Gyongyi Szabo

BACKGROUND/AIMS: Liver diseases are common in the United States and often require liver transplantation; however, donated organs are limited and thus alternative sources for liver cells are in high demand. Embryonic stem cells (ESC) can provide a continuous and readily available source of liver cells. ESC differentiation to liver cells is yet to be fully understood and comprehensive differentiation protocols are yet to be defined. Here, we aimed to achieve human (h)ESC differentiation into mature hepatocytes using defined recombinant differentiation factors and metabolites. METHODS: Embryonic stem cell H1 line was sub-cultured on feeder layer. We induced hESCs into endodermal differentiation …


Escherichia Coli Recg Functionally Suppresses Human Bloom Syndrome Phenotypes, Michael W. Killen, Dawn M. Stults, William A. Wilson, Andrew J. Pierce Oct 2012

Escherichia Coli Recg Functionally Suppresses Human Bloom Syndrome Phenotypes, Michael W. Killen, Dawn M. Stults, William A. Wilson, Andrew J. Pierce

Microbiology, Immunology, and Molecular Genetics Faculty Publications

Defects in the human BLM gene cause Bloom syndrome, notable for early development of tumors in a broad variety of tissues. On the basis of sequence similarity, BLM has been identified as one of the five human homologs of RecQ from Escherichia coli. Nevertheless, biochemical characterization of the BLM protein indicates far greater functional similarity to the E. coli RecG protein and there is no known RecG homolog in human cells. To explore the possibility that the shared biochemistries of BLM and RecG may represent an example of convergent evolution of cellular function where in humans BLM has evolved to …


Decomposing The Energetic Impact Of Drug-Resistant Mutations: The Example Of Hiv-1 Protease-Drv Binding, Yufeng Cai, Celia Schiffer Oct 2012

Decomposing The Energetic Impact Of Drug-Resistant Mutations: The Example Of Hiv-1 Protease-Drv Binding, Yufeng Cai, Celia Schiffer

Celia A. Schiffer

HIV-1 protease is a major drug target for AIDS therapy. With the appearance of drug-resistant HIV-1 protease variants, understanding the mechanism of drug resistance becomes critical for rational drug design. Computational methods can provide more details about inhibitor-protease binding than crystallography and isothermal titration calorimetry. The latest FDA-approved HIV-1 protease inhibitor is Darunavir (DRV). Herein, each DRV atom is evaluated by free energy component analysis for its contribution to the binding affinity with wild-type protease and ACT, a drug-resistant variant. This information can contribute to the rational design of new HIV-1 protease inhibitors.


Gene Expression Analysis Of A Murine Model With Pulmonary Vascular Remodeling Compared To End-Stage Ipah Lungs, Kayoko Shimodaira, Yoichiro Okubo, Eri Ochiai, Haruo Nakayama, Harutaka Katano, Megumi Wakayama, Minoru Shinozaki, Takao Ishiwatari, Daisuke Sasai, Naobumi Tochigi, Tetsuo Nemoto, Tsutomu Saji, Katsuhiko Kamei, Kazutoshi Shibuya Oct 2012

Gene Expression Analysis Of A Murine Model With Pulmonary Vascular Remodeling Compared To End-Stage Ipah Lungs, Kayoko Shimodaira, Yoichiro Okubo, Eri Ochiai, Haruo Nakayama, Harutaka Katano, Megumi Wakayama, Minoru Shinozaki, Takao Ishiwatari, Daisuke Sasai, Naobumi Tochigi, Tetsuo Nemoto, Tsutomu Saji, Katsuhiko Kamei, Kazutoshi Shibuya

Microbiology, Immunology, and Molecular Genetics Faculty Publications

BACKGROUND: Idiopathic pulmonary arterial hypertension (IPAH) continues to be one of the most serious intractable diseases that might start with activation of several triggers representing the genetic susceptibility of a patient. To elucidate what essentially contributes to the onset and progression of IPAH, we investigated factors playing an important role in IPAH by searching discrepant or controversial expression patterns between our murine model and those previously published for human IPAH. We employed the mouse model, which induced muscularization of pulmonary artery leading to hypertension by repeated intratracheal injection of Stachybotrys chartarum, a member of nonpathogenic and ubiquitous fungus in our …


Fus-Nls/Transportin 1 Complex Structure Provides Insights Into The Nuclear Targeting Mechanism Of Fus And The Implications In Als, Chunyan Niu, Jiayu Zhang, Feng Gao, Liuqing Yang, Minze Jia, Haining Zhu, Weimin Gong Oct 2012

Fus-Nls/Transportin 1 Complex Structure Provides Insights Into The Nuclear Targeting Mechanism Of Fus And The Implications In Als, Chunyan Niu, Jiayu Zhang, Feng Gao, Liuqing Yang, Minze Jia, Haining Zhu, Weimin Gong

Molecular and Cellular Biochemistry Faculty Publications

The C-terminal nuclear localization sequence of FUsed in Sarcoma (FUS-NLS) is critical for its nuclear import mediated by transportin (Trn1). Familial amyotrophic lateral sclerosis (ALS) related mutations are clustered in FUS-NLS. We report here the structural, biochemical and cell biological characterization of the FUS-NLS and its clinical implications. The crystal structure of the FUS-NLS/Trn1 complex shows extensive contacts between the two proteins and a unique α-helical structure in the FUS-NLS. The binding affinity between Trn1 and FUS-NLS (wide-type and 12 ALS-associated mutants) was determined. As compared to the wide-type FUS-NLS (K(D) = 1.7 nM), each ALS-associated mutation caused a decreased …


Aspm And The Evolution Of Cerebral Cortical Size In A Community Of New World Monkeys, Fernando A. Villanea, George H. Perry, Gustavo A. Gutiérrez-Espeleta, Nathaniel J. Dominy Sep 2012

Aspm And The Evolution Of Cerebral Cortical Size In A Community Of New World Monkeys, Fernando A. Villanea, George H. Perry, Gustavo A. Gutiérrez-Espeleta, Nathaniel J. Dominy

Dartmouth Scholarship

The ASPM (abnormal spindle-like microcephaly associated) gene has been proposed as a major determinant of cerebral cortical size among primates, including humans. Yet the specific functions of ASPM and its connection to human intelligence remain controversial. This debate is limited in part by a taxonomic focus on Old World monkeys and apes. Here we expand the comparative context of ASPM sequence analyses with a study of New World monkeys, a radiation of primates in which enlarged brain size has evolved in parallel in spider monkeys (genus Ateles) and capuchins (genus Cebus). The primate community of Costa Rica is perhaps a …


Time-Dependent Statistical And Correlation Properties Of Neural Signals During Handwriting, Valery I. Rupasov, Mikhail A. Lebedev, Joseph S. Erlichman, Stephen L. Lee, James C. Leiter, Michael Linderman Sep 2012

Time-Dependent Statistical And Correlation Properties Of Neural Signals During Handwriting, Valery I. Rupasov, Mikhail A. Lebedev, Joseph S. Erlichman, Stephen L. Lee, James C. Leiter, Michael Linderman

Dartmouth Scholarship

To elucidate the cortical control of handwriting, we examined time-dependent statistical and correlational properties of simultaneously recorded 64-channel electroencephalograms (EEGs) and electromyograms (EMGs) of intrinsic hand muscles. We introduced a statistical method, which offered advantages compared to conventional coherence methods. In contrast to coherence methods, which operate in the frequency domain, our method enabled us to study the functional association between different neural regions in the time domain. In our experiments, subjects performed about 400 stereotypical trials during which they wrote a single character. These trials provided time-dependent EMG and EEG data capturing different handwriting epochs. The set of trials …


Health Disparities Experienced By People With Disabilities In The Us: A Behavioral Risk Factor Surveillance System Study, Jennifer Renee Pharr, Timothy J. Bungum Sep 2012

Health Disparities Experienced By People With Disabilities In The Us: A Behavioral Risk Factor Surveillance System Study, Jennifer Renee Pharr, Timothy J. Bungum

Environmental & Occupational Health Faculty Publications

The Americans with Disabilities Act became law in 1990; since then research has shown that people with disabilities continue to experience barriers to health care. The purpose of this study was to compare utilization of preventive services, chronic disease rates, and engagement in health risk behaviors of participants with differing severities of disabilities to those without disabilities. This study was a secondary analysis of 2010 data collected in the Behavioral Risk Factor Surveillance System national survey in the United States. Rao Chi square test and logistic regression were employed. Participants with disabilities had significantly higher adjusted odds ratios for all …


Endogenous Inhibitor Proteins That Connect Ser/Thr Kinases And Phosphatases In Cell Signaling., Masumi Eto, David L Brautigan Sep 2012

Endogenous Inhibitor Proteins That Connect Ser/Thr Kinases And Phosphatases In Cell Signaling., Masumi Eto, David L Brautigan

Department of Molecular Physiology and Biophysics Faculty Papers

Protein phosphatase activity acts as a primary determinant of the extent and duration of phosphorylation of cellular proteins in response to physiological stimuli. Ser/Thr protein phosphatase-1 (PP1) belongs to the PPP superfamily, and is associated with regulatory subunits that confer substrate specificity, allosteric regulation, and subcellular compartmentalization. In addition, all eukaryotic cells contain multiple heat-stable proteins that originally were thought to inhibit phosphatase catalytic subunits released from the regulatory subunits, as a fail-safe mechanism. However, discovery of C-kinase-activated PP1 inhibitor, Mr of 17 kDa (CPI-17) required fresh thinking about the endogenous inhibitors as specific regulators of particular phosphatase complexes, acting …


Plant Calcium Content: Ready To Remodel, Jian Yang, Tracy Punshon, Mary Lou Guerinot, Kendal D. Hirschi Aug 2012

Plant Calcium Content: Ready To Remodel, Jian Yang, Tracy Punshon, Mary Lou Guerinot, Kendal D. Hirschi

Dartmouth Scholarship

By identifying the relationship between calcium location in the plant cell and nutrient bioavailability, the plant characteristics leading to maximal calcium absorption by humans can be identified. Knowledge of plant cellular and molecular targets controlling calcium location in plants is emerging. These insights should allow for better strategies for increasing the nutritional content of foods. In particular, the use of preparation-free elemental imaging technologies such as synchrotron X-ray fluorescence (SXRF) microscopy in plant biology may allow researchers to understand the relationship between subcellular location and nutrient bioavailability. These approaches may lead to better strategies for altering the location of calcium …