Medicine and Health Sciences Commons^™

Circulating Micrornas In Cardiovascular Disease, David Mcmanus, Victor Ambros

Victor R. Ambros

Comment on: Transcoronary concentration gradients of circulating microRNAs. [Circulation. 2011]

Increased Ho-1 Levels Ameliorate Fatty Liver Development Through A Reduction Of Heme And Recruitment Of Fgf21, Terry Hinds, Komal Sodhi, Charles Meadows, Nader Abraham, Larisa Fedorova, Nitin Puri, Dong Kim, Stephen Peterson, Joseph Shapiro, Attallah Kappas

Charles Meadows

Objective Obese leptin deficient (ob/ob) mice are a model of adiposity that displays increased levels of fat, glucose, and liver lipids. Our hypothesis is that HO-1 overexpression ameliorates fatty liver development. Methods Obese mice were administered cobalt protoporphyrin (CoPP) and stannic mesoporphyrin (SnMP) for 6 weeks. Heme, HO-1, HO activity, PGC1α, FGF21, glycogen content, and lipogenesis were assessed. Results CoPP administration increased hepatic HO-1 protein levels and HO activity, decreased hepatic heme, body weight gain, glucose levels, and resulted in decreased steatosis. Increased levels of HO-1 produced a decrease in lipid droplet size, Fatty acid synthase (FAS) levels involving recruitment …

Increased Ho-1 Levels Ameliorate Fatty Liver Development Through A Reduction Of Heme And Recruitment Of Fgf21, Terry Hinds, Komal Sodhi, Charles Meadows, Nader Abraham, Larisa Fedorova, Nitin Puri, Dong Kim, Stephen Peterson, Joseph Shapiro, Attallah Kappas

Nader G. Abraham

Objective Obese leptin deficient (ob/ob) mice are a model of adiposity that displays increased levels of fat, glucose, and liver lipids. Our hypothesis is that HO-1 overexpression ameliorates fatty liver development. Methods Obese mice were administered cobalt protoporphyrin (CoPP) and stannic mesoporphyrin (SnMP) for 6 weeks. Heme, HO-1, HO activity, PGC1α, FGF21, glycogen content, and lipogenesis were assessed. Results CoPP administration increased hepatic HO-1 protein levels and HO activity, decreased hepatic heme, body weight gain, glucose levels, and resulted in decreased steatosis. Increased levels of HO-1 produced a decrease in lipid droplet size, Fatty acid synthase (FAS) levels involving recruitment …

Cyclooxygenase-2 Dependent Metabolism Of 20-Hete Increases Adiposity And Adipocyte Enlargement In Mesenchymal Stem Cell-Derived Adipocytes, Dong Kim, Nitin Puri, Komal Sodhi, John Falck, Nader Abraham, Joseph Shapiro, Michal Schwartzman

Nader G. Abraham

Abstract 20-Hydroxy-5,8,11,14-eicosatetraenoic acid (20-HETE), a product of the cytochrome P450 (CYP)-catalyzed [1] -hydroxylation of arachidonic acid, induces oxidative stress and, in clinical studies, is associated with increased body mass index (BMI) and the metabolic syndrome. This study was designed to examine the effects of exogenous 20- HETE on mesenchymal stem cell (MSC)-derived adipocytes. The expression levels of CYP4A11 and CYP4F2 (major 20-HETE synthases in humans) in MSCs decreased during adipocyte differentiation; however, exogenous administration of 20-HETE (0.1–1 M) increased adipogenesis in a dose dependent manner in these cells ( P < 0.05). The inability of a 20-HETE analog to reproduce these …

Hnrnp A1 And Secondary Structure Coordinate Alternative Splicing Of Mag, Nancy Zearfoss, Emily Johnson, Sean Ryder

Sean P. Ryder

Myelin-associated glycoprotein (MAG) is a major component of myelin in the vertebrate central nervous system. MAG is present in the periaxonal region of the myelin structure, where it interacts with neuronal proteins to inhibit axon outgrowth and protect neurons from degeneration. Two alternatively spliced isoforms of Mag mRNA have been identified. The mRNA encoding the shorter isoform, known as S-MAG, contains a termination codon in exon 12, while the mRNA encoding the longer isoform, known as L-MAG, skips exon 12 and produces a protein with a longer C-terminal region. L-MAG is required in the central nervous system. How inclusion of …

Development Of A Novel Screening Strategy Designed To Discover A New Class Of Hiv Drugs, Nancy Cheng, Sook-Kyung Lee, P. Donover, Mel Reichman, Celia Schiffer, Emily Hull-Ryde, Ronald Swanstrom, William Janzen

Celia A. Schiffer

Current antiretroviral treatments target multiple pathways important for human immunodeficiency virus (HIV) multiplication, including viral entry, synthesis and integration of the DNA provirus, and the processing of viral polyprotein precursors. However, HIV is becoming increasingly resistant to these "combination therapies." Recent findings show that inhibition of HIV Gag protein cleavage into its two structural proteins, matrix (MA) and capsid (CA), has a devastating effect on viral production, revealing a potential new target class for HIV treatment. Unlike the widely used HIV protease inhibitors, this new class of inhibitor would target the substrate, not the protease enzyme itself. This approach offers …

Interview With Celia Schiffer, Celia Schiffer

Celia A. Schiffer

Celia Schiffer, a Professor in Biochemistry and Molecular Pharmacology; a former Director of UMass Center for AIDS Research; and a Founder and Co-Director for the Institute for Drug Resistance (University of Massachusetts Medical School, MA, USA). Schiffer has an undergraduate degree in physics from the University of Chicago, with a PhD in biophysics from University of California, San Francisco (CA, USA). She was a postdoctoral associate first at the ETH in Zurich and then at Genentech in San Francisco. Schiffer has published more than 100 peer reviewed journal articles. Her laboratory primarily uses structural biology, biophysical and chemistry techniques to …

Prototypical Recombinant Multi-Protease Inhibitor Resistant Infectious Molecular Clones Of Human Immunodeficiency Virus Type-1, Vici Varghese, Yumi Mitsuya, W. Jeffrey Fessel, Tommy F. Liu, George Melikian, David Katzenstein, Celia Schiffer, Susan Holmes, Robert Shafer

Celia A. Schiffer

The many genetic manifestations of HIV-1 protease inhibitor (PI) resistance present challenges to research into the mechanisms of PI-resistance and the assessment of new PIs. To address these challenges, we created a panel of recombinant multi-PI resistant infectious molecular clones designed to represent the spectrum of clinically relevant multi-PI resistant viruses. To assess the representativeness of this panel, we examined the sequences of the panel's viruses in the context of a correlation network of PI-resistance amino acid substitutions in sequences from more than 10,000 patients. The panel of recombinant infectious molecular clones comprised 29 of 41 study-defined PI-resistance amino acid …

Dysfunctional Conformational Dynamics Of Protein Kinase A Induced By A Lethal Mutant Of Phospholamban Hinder Phosphorylation, Jonggul Kim, Larry R. Masterson, Alessandro Cembran, Raffaello Verardi, Lei Shi, Jiali Gao, Susan S. Taylor, Gianluigi Veglia

Larry Masterson

Synchronous Opening And Closing Motions Are Essential For Camp-Dependent Protein Kinase A Signaling, Atul K. Srivastava, Leanna R. Mcdonald, Alessandro Cembran, Jonggul Kim, Larry R. Masterson, Christopher L. Mcclendon, Susan S. Taylor, Gianluigi Veglia

Larry Masterson

Characterization Of A Recently Purified Thermophilic Dnase From A Novel Thermophilic Fungus, Kyle Landry, Robert Levin

Kyle S Landry

Development Of A Novel Affinity Membrane Purification System For Deoxyribonuclease, Kyle Landry, Robert Levin

Kyle S Landry

Purification Of An Inducible Dnase From A Thermophilic Fungus, Kyle Landry, Andrea Vu, Robert Levin

Kyle S Landry

Purification And Characterization Of Iso-Ribonucleases From A Novel Thermophilic Fungus, Kyle Landry, Robert Levin

Kyle S Landry

Cooperative Effects Of Drug-Resistance Mutations In The Flap Region Of Hiv-1 Protease, Jennifer Foulkes-Murzycki, Christina Rosi, Nese Yilmaz, Robert Shafer, Celia Schiffer

Celia A. Schiffer

Understanding the interdependence of multiple mutations in conferring drug resistance is crucial to the development of novel and robust inhibitors. As HIV-1 protease continues to adapt and evade inhibitors while still maintaining the ability to specifically recognize and efficiently cleave its substrates, the problem of drug resistance has become more complicated. Under the selective pressure of therapy, correlated mutations accumulate throughout the enzyme to compromise inhibitor binding, but characterizing their energetic interdependency is not straightforward. A particular drug resistant variant (L10I/G48V/I54V/V82A) displays extreme entropy-enthalpy compensation relative to wild-type enzyme but a similar variant (L10I/G48V/I54A/V82A) does not. Individual mutations of sites …

Tca Cycle Inactivation In Staphylococcus Aureus Alters Nitric Oxide Production In Raw 264.7 Cells, Chandirasegaran Massilamany, Arunakumar Gangaplara, Donald Gardner, James Musser, David Steffen, Greg Somerville, Jay Reddy

Greg A. Somerville

Inactivation of the Staphylococcus aureus tricarboxylic acid (TCA) cycle delays the resolution of cutaneous ulcers in a mouse soft tissue infection model. In this study, it was observed that cutaneous lesions in mice infected with wild-type or isogenic aconitase mutant S. aureus strains contained comparable inflammatory infiltrates, suggesting the delayed resolution was independent of the recruitment of immune cells. These observations led us to hypothesize that staphylococcal metabolism can modulate the host immune response. Using an in vitro model system involving RAW 264.7 cells, the authors observed that cells cultured with S. aureus aconitase mutant strains produced significantly lower amounts …

Consumption Of High Ω-3 Fatty Acid Diet Suppressed Prostate Tumorigenesis In C3(1) Tag Mice, Juliana Akinsete, Gabriela Ion, Theodore Witte, W. Hardman

Gabriela Ion

Prostate cancer incidence and mortality are high in the Western world and high ω-6/ω-3 PUFA in the Western diet may be a contributing factor. We investigated whether changing from a diet that approximates ω-6 fat content of the Western diet to a high ω-3 fat diet at adulthood might reduce prostate cancer risk. Female SV 129 mice that had consumed a high ω-6 diet containing corn oil for 2 weeks were bred with homozygous C3(1)Tag transgenic male mice. All male offspring were weaned to the corn oil diet (CO) until postpuberty when half of the male offspring were transferred to …

Non-Helicobacter Pylori Related Duodenal Ulcer Disease In Children, Yoram Elitsur, Zandra Lawrence

Yoram Elitsur

Background. In spite of the worldwide distribution of Helicobacter pylori infection, recent data have reported an increased rate of non-H. pylori, non-NSAIDs-duodenal ulcer disease in adults. The estimated rate of these ulcers in children is unknown. We aimed to investigate the prevalence of non-H. pylori, non-NSAIDs-peptic ulcer disease in our pediatric patients who undergo upper endoscopic procedures. Methods. A retrospective analysis of 622 upper endoscopic reports was performed. Reports that documented mucosal ulcerations were included in our study. The demographic, clinical, endoscopic, and histological data were retrieved. The H. pylori-negative, duodenal/gastric ulcer-positive patients were compared with H. pylori-positive, duodenal/gastric ulcer-positive …

Is Sudden Infant Death Syndrome Associated With Helicobacter Pylori Infection In Children?, Yoram Elitsur, William Btriest, Zia Sabet, Cheryl Neace, Chuancang Jiang, Eapen Thomas

Yoram Elitsur

Helicobacter pylori infection has recently been implicated in the pathogenesis of sudden infant death syndrome (SIDS). We investigated this association. Twenty-five pairs of gastric and tracheal tissue specimens obtained from autopsies of 25 children with previous diagnoses of SIDS were available for this study. The presence of H. pylori organisms was evaluated by three different methods: histology (hematoxylin-eosin or Giemsa staining), immunohistochemistry, and nested polymerase chain reaction technique. We were unable to confirm the presence of H. pylori organisms by the first two methods. H. pylori DNA was identified by nested polymerase chain reaction in six different tissue specimens (stomach, …

Global Analysis Of Gene Expression Changes During Retinoic Acid-Induced Growth Arrest And Differentiation Of Melanoma: Comparison To Differentially Expressed Genes In Melanocytes Vs Melanoma, Mary Estler, Goran Boskovic, James Denvir, Sarah Miles, Donald Primerano, Richard Niles

James Denvir

BACKGROUND: The incidence of malignant melanoma has significantly increased over the last decade. Some of these malignancies are susceptible to the growth inhibitory and pro-differentiating effects of all-trans-retinoic acid (RA). The molecular changes responsible for the biological activity of RA in melanoma are not well understood. RESULTS: In an analysis of sequential global gene expression changes during a 4-48 h RA treatment of B16 mouse melanoma cells, we found that RA increased the expression of 757 genes and decreased the expression of 737 genes. We also compared the gene expression profile (no RA treatment) between non-malignant melan-a mouse melanocytes and …

Conformational Equilibrium Of N-Myristoylated Camp-Dependent Protein Kinase A By Molecular Dynamics Simulations, Alessandro Cembran, Larry R. Masterson, Christopher L. Mcclendon, Susan S. Taylor, Jiali Gao, Gianluigi Veglia

Larry Masterson

Competition Between Ski And Creb-Binding Protein For Binding To Smad Proteins In Transforming Growth Factor-Beta Signaling, Weijun Chen, Suvana Lam, Hema Srinath, Celia Schiffer, William Royer, Kai Lin

Celia A. Schiffer

The family of Smad proteins mediates transforming growth factor-beta (TGF-beta) signaling in cell growth and differentiation. Smads repress or activate TGF-beta signaling by interacting with corepressors (e.g. Ski) or coactivators (e.g. CREB-binding protein (CBP)), respectively. Specifically, Ski has been shown to interfere with the interaction between Smad3 and CBP. However, it is unclear whether Ski competes with CBP for binding to Smads and whether they can interact with Smad3 at the same binding surface on Smad3. We investigated the interactions among purified constructs of Smad, Ski, and CBP in vitro by size-exclusion chromatography, isothermal titration calorimetry, and mutational studies. Here, …

Mass Spectrometry Analysis Of Hiv-1 Vif Reveals An Increase In Ordered Structure Upon Oligomerization In Regions Necessary For Viral Infectivity, Jared Auclair, Karin Green, Shivender Shandilya, James Evans, Mohan Somasundaran, Celia Schiffer

Celia A. Schiffer

HIV-1 Vif, an accessory protein in the viral genome, performs an important role in viral pathogenesis by facilitating the degradation of APOBEC3G, an endogenous cellular inhibitor of HIV-1 replication. In this study, intrinsically disordered regions are predicted in HIV-1 Vif using sequence-based algorithms. Intrinsic disorder may explain why traditional structure determination of HIV-1 Vif has been elusive, making structure-based drug design impossible. To characterize HIV-1 Vif's structural topology and to map the domains involved in oligomerization we used chemical cross-linking, proteolysis, and mass spectrometry. Cross-linking showed evidence of monomer, dimer, and trimer species via denaturing gel analysis and an additional …

Exploring The Role Of The Solvent In The Denaturation Of A Protein: A Molecular Dynamics Study Of The Dna Binding Domain Of The 434 Repressor, Celia Schiffer, Volker Dötsch, Kurt Wuthrich, Wilfred Van Gunsteren

Celia A. Schiffer

Molecular dynamics simulations of the DNA binding domain of 434 repressor are presented which aim at unraveling the role of solvent in protein denaturation. Four altered solvent models, each mimicking various possible aspects of the addition of a denaturant to the aqueous solvent, were used in the simulations to analyze their effects on the stability of the protein. The solvent was altered by selectively changing the Coulombic interaction between water and protein atoms and between different water molecules. The use of a modified solvent model has the advantage of mimicking the presence of denaturant without having denaturant molecules present in …

Structural Analysis Of Human Immunodeficiency Virus Type 1 Crf01_Ae Protease In Complex With The Substrate P1-P6., Rajintha Bandaranayake, Moses Prabu-Jeyabalan, Junko Kakizawa, Wataru Sugiura, Celia Schiffer

Celia A. Schiffer

The effect of amino acid variability between human immunodeficiency virus type 1 (HIV-1) clades on structure and the emergence of resistance mutations in HIV-1 protease has become an area of significant interest in recent years. We determined the first crystal structure of the HIV-1 CRF01_AE protease in complex with the p1-p6 substrate to a resolution of 2.8 A. Hydrogen bonding between the flap hinge and the protease core regions shows significant structural rearrangements in CRF01_AE protease compared to the clade B protease structure.

Micrornas Are Independent Predictors Of Outcome In Diffuse Large B-Cell Lymphoma Patients Treated With R-Chop, Goldi Kozloski

Goldi A Kozloski

Muc4/Muc4 Functions And Regulation In Cancer., Goldi Kozloski

Goldi A Kozloski

Hdl-Cholesterol-Raising Effect Of Orange Juice In Subjects With Hypercholesterolemia, Elzbieta Kurowska, J. Spence, John Jordan, Stephen Wetmore, David Freeman, Leonard Piché, Paula Serratore

Leonard Piché

Background: Orange juice-a rich source of vitamin C, folate, and flavonoids such as hesperidin-induces hypocholesterolemic responses in animals. Objective: We determined whether orange juice beneficially altered blood lipids in subjects with moderate hypercholesterolemia. Design: The sample consisted of 16 healthy men and 9 healthy women with elevated plasma total and LDL-cholesterol and normal plasma triacylglycerol concentrations. Participants incorporated 1, 2, or 3 cups (250 mL each) of orange juice sequentially into their diets, each dose over a period of 4 wk. This was followed by a 5-wk washout period. Plasma lipid, folate, homocyst(e)ine, and vitamin C (a compliance marker) concentrations …

Role Of Transglutaminase 2 In Liver Injury Via Cross-Linking And Silencing Of Transcription Factor Sp1., Hideki Tatsukawa, Yayoi Fukaya, Gordon Frampton, Antonio Martinez-Fuentes, Kenji Suzuki, Ting-Fang Kuo, Keisuke Nagatsuma, Kentaro Shimokado, Masataka Okuno, Jian Wu, Siiri Iismaa, Tomokazu Matsuura, Hidekazu Tsukamoto, Mark A Zern, Robert M Graham, Soichi Kojima

jian duan wu

BACKGROUND & AIMS: Despite high morbidity and mortality of alcoholic liver disease worldwide, the molecular mechanisms underlying alcohol-induced liver cell death are not fully understood. Transglutaminase 2 (TG2) is a cross-linking enzyme implicated in apoptosis. TG2 levels and activity are increased in association with various types of liver injury. However, how TG2 induces hepatic apoptosis is not known. METHODS: Human hepatic cells or primary hepatocytes from rats or TG2+/+ and TG2-/- mice were treated with ethanol. Mice were administered anti-Fas antibody or alcohol. Liver sections were prepared from patients with alcoholic steatohepatitis. Changes in TG2 levels, Sp1 cross-linking and its …

Structural And Dynamic Basis Of Phospholamban And Sarcolipin Inhibition Of Ca2+-Atpase, Nathaniel J. Traaseth, Kim N. Ha, Raffaello Verardi, Lei Shi, Jarrod J. Buffy, Larry R. Masterson, Gianluigi Veglia

Larry Masterson