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Full-Text Articles in Medical Sciences

Accelerated Forgetting In People With Epilepsy: Pathologic Memory Loss, Its Neural Basis, And Potential Therapies, Sarah Ashley Steimel Phd Jan 2023

Accelerated Forgetting In People With Epilepsy: Pathologic Memory Loss, Its Neural Basis, And Potential Therapies, Sarah Ashley Steimel Phd

Dartmouth College Ph.D Dissertations

While forgetting is vital to human functioning, delineating between normative and disordered forgetting can become incredibly complex. This thesis characterizes a pathologic form of forgetting in epilepsy, identifies a neural basis, and investigates the potential of stimulation as a therapeutic tool. Chapter 2 presents a behavioral characterization of the time course of Accelerated Long-Term Forgetting (ALF) in people with epilepsy (PWE). This chapter shows evidence of ALF on a shorter time scale than previous studies, with a differential impact on recall and recognition. Chapter 3 builds upon the work in Chapter 2 by extending ALF time points and investigating the …


Intrinsic And Innate Defenses Of Neurons: Détente With The Herpesviruses, Lynn Enquist, David A. Leib Oct 2017

Intrinsic And Innate Defenses Of Neurons: Détente With The Herpesviruses, Lynn Enquist, David A. Leib

Dartmouth Scholarship

Neuroinvasive herpesviruses have evolved to efficiently infect and establish latency in neurons. The nervous system has limited capability to regenerate, so immune responses therein are carefully regulated to be nondestructive, with dependence on atypical intrinsic and innate defenses. In this article we review studies of some of these noncanonical defense pathways and how herpesvirus gene products counter them, highlighting the contributions that primary neuronal in vitro models have made to our understanding of this field.


Aspergillus Fumigatus Trehalose-Regulatory Subunit Homolog Moonlights To Mediate Cell Wall Homeostasis Through Modulation Of Chitin Synthase Activity, Arsa Thammahong, Alayna K. Caffrey-Card, Sourabh Dhingra, Joshua J. Obar, Robert Cramer Apr 2017

Aspergillus Fumigatus Trehalose-Regulatory Subunit Homolog Moonlights To Mediate Cell Wall Homeostasis Through Modulation Of Chitin Synthase Activity, Arsa Thammahong, Alayna K. Caffrey-Card, Sourabh Dhingra, Joshua J. Obar, Robert Cramer

Dartmouth Scholarship

Trehalose biosynthesis is found in fungi but not humans. Proteins involved in trehalose biosynthesis are essential for fungal pathogen virulence in humans and plants through multiple mechanisms. Loss of canonical trehalose biosynthesis genes in the human pathogen Aspergillus fumigatus significantly alters cell wall structure and integrity, though the mechanistic link between these virulence-associated pathways remains enigmatic. Here we characterize genes, called tslAand tslB, which encode proteins that contain domains similar to those corresponding to trehalose-6-phosphate phosphatase but lack critical catalytic residues for phosphatase activity. Loss of tslA reduces trehalose content in both conidia and mycelia, impairs cell wall …


Filamentous Fungal Carbon Catabolite Repression Supports Metabolic Plasticity And Stress Responses Essential For Disease Progression, Sarah R. Beattie, Kenneth Mark, Arsa Thammahong, Laure Nicolas Annick Ries, Sourabh Dhingra, Alayna Caffrey-Carr, Chao Cheng Apr 2017

Filamentous Fungal Carbon Catabolite Repression Supports Metabolic Plasticity And Stress Responses Essential For Disease Progression, Sarah R. Beattie, Kenneth Mark, Arsa Thammahong, Laure Nicolas Annick Ries, Sourabh Dhingra, Alayna Caffrey-Carr, Chao Cheng

Dartmouth Scholarship

Aspergillus fumigatus is responsible for a disproportionate number of invasive mycosis cases relative to other common filamentous fungi. While many fungal factors critical for infection establishment are known, genes essential for disease persistence and progression are ill defined. We propose that fungal factors that promote navigation of the rapidly changing nutrient and structural landscape characteristic of disease progression represent untapped clinically relevant therapeutic targets. To this end, we find that A. fumigatus requires a carbon catabolite repression (CCR) mediated genetic network to support in vivo fungal fitness and disease progression. While CCR as mediated by the transcriptional repressor CreA is …


Cis-Eqtl-Based Trans-Ethnic Meta-Analysis Reveals Novel Genes Associated With Breast Cancer Risk, Joshua Hoffman, Rebecca Graff, Nima Emami, Caroline Tai, Michael Passarelli Mar 2017

Cis-Eqtl-Based Trans-Ethnic Meta-Analysis Reveals Novel Genes Associated With Breast Cancer Risk, Joshua Hoffman, Rebecca Graff, Nima Emami, Caroline Tai, Michael Passarelli

Dartmouth Scholarship

Breast cancer is the most common solid organ malignancy and the most frequent cause of cancer death among women worldwide. Previous research has yielded insights into its genetic etiology, but there remains a gap in the understanding of genetic factors that contribute to risk, and particularly in the biological mechanisms by which genetic variation modulates risk. The National Cancer Institute's "Up for a Challenge" (U4C) competition provided an opportunity to further elucidate the genetic basis of the disease. Our group leveraged the seven datasets made available by the U4C organizers and data from the publicly available UK Biobank cohort to …


A Novel Multi-Network Approach Reveals Tissue-Specific Cellular Modulators Of Fibrosis In Systemic Sclerosis, Jaclyn N. Taroni, Casey S. Greene, Viktor Martyanov, Tammara A. Wood Mar 2017

A Novel Multi-Network Approach Reveals Tissue-Specific Cellular Modulators Of Fibrosis In Systemic Sclerosis, Jaclyn N. Taroni, Casey S. Greene, Viktor Martyanov, Tammara A. Wood

Dartmouth Scholarship

Systemic sclerosis (SSc) is a multi-organ autoimmune disease characterized by skin fibrosis. Internal organ involvement is heterogeneous. It is unknown whether disease mechanisms are common across all involved affected tissues or if each manifestation has a distinct underlying pathology.We used consensus clustering to compare gene expression profiles of biopsies from four SSc-affected tissues (skin, lung, esophagus, and peripheral blood) from patients with SSc, and the related conditions pulmonary fibrosis (PF) and pulmonary arterial hypertension, and derived a consensus disease-associate signature across all tissues. We used this signature to query tissue-specific functional genomic networks. We performed novel network analyses to contrast …


A New Class Of Inhibitors Of The Arac Family Virulence Regulator Vibrio Cholerae Toxt, Anne K. Woodbrey, Evans O. Onyango, Maria Pellegrini, Gabriela Kovacikova, Ronald Taylor, Gordon Gribble, F. Jon Kull Mar 2017

A New Class Of Inhibitors Of The Arac Family Virulence Regulator Vibrio Cholerae Toxt, Anne K. Woodbrey, Evans O. Onyango, Maria Pellegrini, Gabriela Kovacikova, Ronald Taylor, Gordon Gribble, F. Jon Kull

Dartmouth Scholarship

Vibrio cholerae is responsible for the diarrheal disease cholera that infects millions of people worldwide. While vaccines protecting against cholera exist, and oral rehydration therapy is an effective treatment method, the disease will remain a global health threat until long-term solutions such as improved sanitation and access to clean water become widely available. Because of this, there is a pressing need for potent therapeutics that can either mitigate cholera symptoms, or act prophylactically to prevent the virulent effects of a cholera infection. Here we report the design, synthesis, and characterization of a set of compounds that bind and inhibit ToxT, …


Potent Single-Domain Antibodies That Arrest Respiratory Syncytial Virus Fusion Protein In Its Prefusion State, Iebe Rossey, Morgan Gilman, Stephanie Kabeche, Koen Sedeyn, Daniel Wrapp Feb 2017

Potent Single-Domain Antibodies That Arrest Respiratory Syncytial Virus Fusion Protein In Its Prefusion State, Iebe Rossey, Morgan Gilman, Stephanie Kabeche, Koen Sedeyn, Daniel Wrapp

Dartmouth Scholarship

Human respiratory syncytial virus (RSV) is the main cause of lower respiratory tract infections in young children. The RSV fusion protein (F) is highly conserved and is the only viral membrane protein that is essential for infection. The prefusion conformation of RSV F is considered the most relevant target for antiviral strategies because it is the fusion-competent form of the protein and the primary target of neutralizing activity present in human serum. Here, we describe two llama-derived single-domain antibodies (VHHs) that have potent RSV-neutralizing activity and bind selectively to prefusion RSV F with picomolar affinity. Crystal structures of these VHHs …


Pseudomonas Aeruginosa Sabotages The Generation Of Host Proresolving Lipid Mediators, Becca A. Flitter, Kelli L. Hvorecny, Emiko Ono, Taylor Eddens Jan 2017

Pseudomonas Aeruginosa Sabotages The Generation Of Host Proresolving Lipid Mediators, Becca A. Flitter, Kelli L. Hvorecny, Emiko Ono, Taylor Eddens

Dartmouth Scholarship

Recurrent Pseudomonas aeruginosa infections coupled with robust, damaging neutrophilic inflammation characterize the chronic lung disease cystic fibrosis (CF). The proresolving lipid mediator, 15-epi lipoxin A4 (15-epi LXA4), plays a critical role in limiting neutrophil activation and tissue inflammation, thus promoting the return to tissue homeostasis. Here, we show that a secreted P. aeruginosa epoxide hydrolase, cystic fibrosis transmembrane conductance regulator inhibitory factor (Cif), can disrupt 15-epi LXA4 transcellular biosynthesis and function. In the airway, 15-epi LXA4 production is stimulated by the epithelial-derived eicosanoid 14,15-epoxyeicosatrienoic acid (14,15-EET). Cif sabotages the production of 15-epi LXA4 by rapidly hydrolyzing 14,15-EET into its cognate …


5-Hydroxymethylcytosine Localizes To Enhancer Elements And Is Associated With Survival In Glioblastoma Patients, Kevin C. Johnson, E. Andres Houseman, Jessica E. King, Katharine M. Von Herrmann, Camilo E. Fadu, Brock C. Christensen Nov 2016

5-Hydroxymethylcytosine Localizes To Enhancer Elements And Is Associated With Survival In Glioblastoma Patients, Kevin C. Johnson, E. Andres Houseman, Jessica E. King, Katharine M. Von Herrmann, Camilo E. Fadu, Brock C. Christensen

Dartmouth Scholarship

Glioblastomas exhibit widespread molecular alterations including a highly distorted epigenome. Here, we resolve genome-wide 5-methylcytosine and 5-hydroxymethylcytosine in glioblastoma through parallel processing of DNA with bisulfite and oxidative bisulfite treatments. We apply a statistical algorithm to estimate 5-methylcytosine, 5-hydroxymethylcytosine and unmethylated proportions from methylation array data. We show that 5-hydroxymethylcytosine is depleted in glioblastoma compared with prefrontal cortex tissue. In addition, the genomic localization of 5-hydroxymethylcytosine in glioblastoma is associated with features of dynamic cell-identity regulation such as tissue-specific transcription and super-enhancers. Annotation of 5-hydroxymethylcytosine genomic distribution reveal significant associations with RNA regulatory processes, immune function, stem cell maintenance and …


Constitutively Activated Pi3k Accelerates Tumor Initiation And Modifies Histopathology Of Breast Cancer, M. R. Sheen, J. D. Marotti, M. J. Allegrezza, M. Rutkowski, J. R. Conejo-Garcia, S. Fiering Oct 2016

Constitutively Activated Pi3k Accelerates Tumor Initiation And Modifies Histopathology Of Breast Cancer, M. R. Sheen, J. D. Marotti, M. J. Allegrezza, M. Rutkowski, J. R. Conejo-Garcia, S. Fiering

Dartmouth Scholarship

The gene encoding phosphatidylinositol 3-kinase catalytic subunit α-isoform (PIK3CA, p110α) is frequently activated by mutation in human cancers. Based on detection in some breast cancer precursors, PIK3CA mutations have been proposed to have a role in tumor initiation. To investigate this hypothesis, we generated a novel mouse model with a Cre-recombinase regulated allele of p110α (myristoylated-p110α, myr-p110α) along with p53fl/fl deletion and KrasG12D also regulated by Cre-recombinase. After instillation of adenovirus-expressing Cre-recombinase into mammary ducts, we found that myr-p110α accelerated breast tumor initiation in a copy number-dependent manner. Breast tumors induced by p53fl/fl;KrasG12D with no or one copy of myr-p110α …


Immune- And Nonimmune-Compartment-Specific Interferon Responses Are Critical Determinants Of Herpes Simplex Virus-Induced Generalized Infections And Acute Liver Failure, Zachary M. Parker, Tracy Jo Pasieka, George A. Parker, David A. Leib Sep 2016

Immune- And Nonimmune-Compartment-Specific Interferon Responses Are Critical Determinants Of Herpes Simplex Virus-Induced Generalized Infections And Acute Liver Failure, Zachary M. Parker, Tracy Jo Pasieka, George A. Parker, David A. Leib

Dartmouth Scholarship

The interferon (IFN) response to viral pathogens is critical for host survival. In humans and mouse models, defects in IFN responses can result in lethal herpes simplex virus 1 (HSV-1) infections, usually from encephalitis. Although rare, HSV-1 can also cause fulminant hepatic failure, which is often fatal. Although herpes simplex encephalitis has been extensively studied, HSV-1 generalized infections and subsequent acute liver failure are less well understood. We previously demonstrated that IFN-αβγR-/- mice are exquisitely susceptible to liver infection following corneal infection with HSV-1. In this study, we used bone marrow chimeras of IFN-αβγR-/- (AG129) and wild-type (WT; 129SvEv) mice …


Microrna Mir-155 Is Necessary For Efficient Gammaherpesvirus Reactivation From Latency, But Not For Establishment Of Latency, Rebecca L. Crepeau, Peisheng Zhang, Edward J. Usherwood Jun 2016

Microrna Mir-155 Is Necessary For Efficient Gammaherpesvirus Reactivation From Latency, But Not For Establishment Of Latency, Rebecca L. Crepeau, Peisheng Zhang, Edward J. Usherwood

Dartmouth Scholarship

MicroRNA-155 (miR-155) has been shown to play significant roles in the immune response, including in the formation of germinal centers (GC) and the development and maturation of T follicular helper (Tfh) cells. There is in vitro evidence to support a critical role for cellular miR-155 and viral miR-155 homologs in the establishment of gammaherpesvirus latency in B cells. We sought to determine the contribution of miR-155 to the establishment and maintenance of latency in vivousing murine gammaherpesvirus (MHV-68) infection. MHV-68-infected mice deficient in miR-155 exhibited decreases in GC B cells and Tfh cells. However, the frequencies of spleen cells …


Elevated Mtss1 Expression Associated With Metastasis And Poor Prognosis Of Residual Hepatitis B-Related Hepatocellular Carcinoma, Xiu-Yan Huang, Zi-Li Huang, Bin Xu, Zi Chen May 2016

Elevated Mtss1 Expression Associated With Metastasis And Poor Prognosis Of Residual Hepatitis B-Related Hepatocellular Carcinoma, Xiu-Yan Huang, Zi-Li Huang, Bin Xu, Zi Chen

Dartmouth Scholarship

Background: Hepatectomy generally offers the best chance of long-term survival for patients with hepatocellular carcinoma (HCC). Many studies have shown that hepatectomy accelerates tumor metastasis, but the mechanism remains unclear.

Methods: An orthotopic nude mice model with palliative HCC hepatectomy was performed in this study. Metastasis-related genes in tumor following resection were screened; HCC invasion, metastasis, and some molecular alterations were examined in vivo and in vitro. Clinical significance of key gene mRNA expression was also analyzed.


Expression Of Complement And Toll-Like Receptor Pathway Genes Is Associated With Malaria Severity In Mali: A Pilot Case Control Study, Rafal S. Sobota, Antoine Dara, Jessica E. Manning, Amadou Niangaly Mar 2016

Expression Of Complement And Toll-Like Receptor Pathway Genes Is Associated With Malaria Severity In Mali: A Pilot Case Control Study, Rafal S. Sobota, Antoine Dara, Jessica E. Manning, Amadou Niangaly

Dartmouth Scholarship

Background: The host response to infection by Plasmodium falciparum, the parasite most often responsible for severe malaria, ranges from asymptomatic parasitaemia to death. The clinical trajectory of malaria is influenced by host genetics and parasite load, but the factors determining why some infections produce uncomplicated malaria and some proceed to severe disease remain incompletely understood.

Methods: To identify molecular markers of severe falciparum malaria, human gene expression patterns were compared between children aged 6 months to 5 years with severe and uncomplicated malaria who were enrolled in a case–control study in Bandiagara, Mali. Microarrays were used to obtain expression …


Herpes Simplex Virus And Interferon Signaling Induce Novel Autophagic Clusters In Sensory Neurons, Sarah Katzenell, David A. Leib Feb 2016

Herpes Simplex Virus And Interferon Signaling Induce Novel Autophagic Clusters In Sensory Neurons, Sarah Katzenell, David A. Leib

Dartmouth Scholarship

Herpes simplex virus 1 (HSV-1) establishes lifelong infection in the neurons of trigeminal ganglia (TG), cycling between productive infection and latency. Neuronal antiviral responses are driven by type I interferon (IFN) and are crucial to controlling HSV-1 virulence. Autophagy also plays a role in this neuronal antiviral response, but the mechanism remains obscure. In this study, HSV-1 infection of murine TG neurons triggered unusual clusters of autophagosomes, predominantly in neurons lacking detectable HSV-1 antigen. Treatment of neurons with IFN-β induced a similar response, and cluster formation by infection or IFN treatment was dependent upon an intact IFN-signaling pathway. The autophagic …


In Vitro Modeling Of The Interaction Between Human Epithelial Cells And Lymphocytes Upon Influenza Infection, Natalia A. Ilyushina, Pete F. Wright Jan 2016

In Vitro Modeling Of The Interaction Between Human Epithelial Cells And Lymphocytes Upon Influenza Infection, Natalia A. Ilyushina, Pete F. Wright

Dartmouth Scholarship

Influenza viruses are a continuous threat to humans because of their ability to cross species barriers and adapt to new hosts. Data from murine studies, along with limited human data, suggest that CD8(+) cytotoxic T lymphocytes (CTL) that recognize conserved epitopes of structural influenza proteins are the main mediators of influenza virus clearance. Additionally, the fact that many CTLs recognize epitopes shared between different influenza strains offers the potential for broad cross-strain immunity. However, the mechanisms of cellular immunity against influenza viruses are poorly defined in humans, where the CTL response has been hard to measure and interpret. We developed …


Characterization Of The Paracoccidioides Hypoxia Response Reveals New Insights Into Pathogenesis Mechanisms Of This Important Human Pathogenic Fungus, Patrícia De Sousa Lima, Dawoon Chung, Alexandre Melo Bailão, Robert A. Cramer, Célia Maria De Almeida Soares Dec 2015

Characterization Of The Paracoccidioides Hypoxia Response Reveals New Insights Into Pathogenesis Mechanisms Of This Important Human Pathogenic Fungus, Patrícia De Sousa Lima, Dawoon Chung, Alexandre Melo Bailão, Robert A. Cramer, Célia Maria De Almeida Soares

Dartmouth Scholarship

Background: Hypoxic microenvironments are generated during fungal infection. It has been described that to survive in the human host, fungi must also tolerate and overcome in vivo microenvironmental stress conditions including low oxygen tension; however nothing is known how Paracoccidioides species respond to hypoxia. The genus Paracoccidioides comprises human thermal dimorphic fungi and are causative agents of paracoccidioidomycosis (PCM), an important mycosis in Latin America.


Cyclin-Dependent Kinase Inhibitor P1446a Induces Apoptosis In A Jnk/P38 Mapk-Dependent Manner In Chronic Lymphocytic Leukemia B-Cells, Cody Paiva, J. Claire Godbersen, Ryan S. Soderquist, Taylor Rowland, Sumner Kilmarx Nov 2015

Cyclin-Dependent Kinase Inhibitor P1446a Induces Apoptosis In A Jnk/P38 Mapk-Dependent Manner In Chronic Lymphocytic Leukemia B-Cells, Cody Paiva, J. Claire Godbersen, Ryan S. Soderquist, Taylor Rowland, Sumner Kilmarx

Dartmouth Scholarship

CDK (cyclin-dependent kinase) inhibitors have shown remarkable activity in CLL, where its efficacy has been linked to inhibition of the transcriptional CDKs (7 and 9) and deregulation of RNA polymerase and short-lived pro-survival proteins such as MCL1. Furthermore, ER (endoplasmic reticulum) stress has been implicated in CDK inhibition in CLL. Here we conducted a pre-clinical study of a novel orally active kinase inhibitor P1446A in CLL B-cells. P1446A inhibited CDKs at nanomolar concentrations and induced rapid apoptosis of CLL cells in vitro, irrespective of chromosomal abnormalities or IGHV mutational status. Apoptosis preceded inactivation of RNA polymerase, and was accompanied by …


Amikacin Concentrations Predictive Of Ototoxicity In Multidrug-Resistant Tuberculosis Patients, Chawangwa Modongo, Jotam G. Pasipanodya, Nicola M. Zetola, Scott M. Williams Jul 2015

Amikacin Concentrations Predictive Of Ototoxicity In Multidrug-Resistant Tuberculosis Patients, Chawangwa Modongo, Jotam G. Pasipanodya, Nicola M. Zetola, Scott M. Williams

Dartmouth Scholarship

Aminoglycosides, such as amikacin, are used to treat multidrug-resistant tuberculosis. However, ototoxicity is a common problem and is monitored using peak and trough amikacin concentrations based on World Health Organization recommendations. Our objective was to identify clinical factors predictive of ototoxicity using an agnostic machine learning method. We used classification and regression tree (CART) analyses to identify clinical factors, including amikacin concentration t

hresholds that pre- dicted audiometry-confirmed ototoxicity among 28 multidrug-resistant pulmonary tuberculosis patients in Botswana. Amika- cin concentrations were measured for all patients. The quantitative relationship between predictive factors and the probability of ototoxicity were then identified using …


A Novel Caspase 8 Selective Small Molecule Potentiates Trail-Induced Cell Death, Octavian Bucur, Gabriel Gaidos, Achani Yatawara, Bodvael Pennarun, Chamila Rupasinghe, Jérémie Roux, Stefan Andrei, Bingqian Guo, Alexandra Panaitiu, Maria Pellegrini, Dale Mierke, Roya Khosravi-Far May 2015

A Novel Caspase 8 Selective Small Molecule Potentiates Trail-Induced Cell Death, Octavian Bucur, Gabriel Gaidos, Achani Yatawara, Bodvael Pennarun, Chamila Rupasinghe, Jérémie Roux, Stefan Andrei, Bingqian Guo, Alexandra Panaitiu, Maria Pellegrini, Dale Mierke, Roya Khosravi-Far

Dartmouth Scholarship

Recombinant soluble TRAIL and agonistic antibodies against TRAIL receptors (DR4 and DR5) are currently being created for clinical cancer therapy, due to their selective killing of cancer cells and high safety characteristics. However, resistance to TRAIL and other targeted therapies is an important issue facing current cancer research field. An attractive strategy to sensitize resistant malignancies to TRAIL-induced cell death is the design of small molecules that target and promote caspase 8 activation. For the first time, we describe the discovery and characterization of a small molecule that directly binds caspase 8 and enhances its activation when combined with TRAIL, …


Site-Specific Immunomodulator: A Novel Treatment For Crohn's Disease, Brian Bressler, Kevin P. Bethel, Ralf Kleef, Sophie L. Reynolds, Simon Sutcliffe, David W. Mullins, Hal Gunn Apr 2015

Site-Specific Immunomodulator: A Novel Treatment For Crohn's Disease, Brian Bressler, Kevin P. Bethel, Ralf Kleef, Sophie L. Reynolds, Simon Sutcliffe, David W. Mullins, Hal Gunn

Dartmouth Scholarship

We investigated the mechanism of action, safety, and efficacy of the Site-Specific Immunomodulator (SSI) QBECO, a novel immunotherapy for Crohn’s disease (CD). Using human monocytic THP-1 cells, we demonstrate that SSI QBECO (derived from the common colon bacteria E. coli) activates macrophages to an M1 phenotype (associated with enhanced capacity to eliminate bacteria and activate innate immune responses). We assessed SSI QBECO in a compassionate use protocol of ten adult patients with active CD. Patients with moderate to severe clinical symptoms receiving conventional CD treatments and/or complementary therapies were included, except patients receiving anti-TNF medications. SSI QBECO was self-administered subcutaneously …


Systems Level Analysis Of Systemic Sclerosis Shows A Network Of Immune And Profibrotic Pathways Connected With Genetic Polymorphisms, J. Matthew Mahoney, Jaclyn Taroni, Viktor Martyanov, Tammara A. A. Wood, Casey S. Greene, Patricia A. Pioli, Monique E. Hinchcliff, Michael L. Whitfield Jan 2015

Systems Level Analysis Of Systemic Sclerosis Shows A Network Of Immune And Profibrotic Pathways Connected With Genetic Polymorphisms, J. Matthew Mahoney, Jaclyn Taroni, Viktor Martyanov, Tammara A. A. Wood, Casey S. Greene, Patricia A. Pioli, Monique E. Hinchcliff, Michael L. Whitfield

Dartmouth Scholarship

Systemic sclerosis (SSc) is a rare systemic autoimmune disease characterized by skin and organ fibrosis. The pathogenesis of SSc and its progression are poorly understood. The SSc intrinsic gene expression subsets (inflammatory, fibroproliferative, normal-like, and limited) are observed in multiple clinical cohorts of patients with SSc. Analysis of longitudinal skin biopsies suggests that a patient's subset assignment is stable over 6-12 months. Genetically, SSc is multi-factorial with many genetic risk loci for SSc generally and for specific clinical manifestations. Here we identify the genes consistently associated with the intrinsic subsets across three independent cohorts, show the relationship between these genes …


A Coding Variant In Tmc8 (Ever2) Is Associated With High Risk Hpv Infection And Head And Neck Cancer Risk, Caihua Liang, Karl T. Kelsey, Michael D. Mcclean, Brock C. Christensen, Carmen J. Marsit Jan 2015

A Coding Variant In Tmc8 (Ever2) Is Associated With High Risk Hpv Infection And Head And Neck Cancer Risk, Caihua Liang, Karl T. Kelsey, Michael D. Mcclean, Brock C. Christensen, Carmen J. Marsit

Dartmouth Scholarship

HPV infection is a causal agent in many epithelial cancers, yet our understanding of genetic susceptibility to HPV infection and resultant cancer risk is limited. Epidermodysplasia Verruciformis is a rare condition of extreme susceptibility to cutaneous HPV infection primarily attributable to mutations in TMC6 and TMC8. Genetic variation in the TMC6/TMC8 region has been linked to beta-type HPV infection and squamous cell carcinoma of the skin, cervical cancer, HPV persistence and progression to cervical cancer. Here, we have tested the hypothesis that the common TMC8 SNP rs7208422 is associated with high-risk HPV infection and risk of head and neck …


Syndecan 4 Is Required For Endothelial Alignment In Flow And Atheroprotective Signaling, Nicolas Baeyens, Mary Jo Mulligan-Kehoe, Federico Corti, David D. Simon, Tyler D. Ross, John M. Rhodes, Thomas Z. Wang Dec 2014

Syndecan 4 Is Required For Endothelial Alignment In Flow And Atheroprotective Signaling, Nicolas Baeyens, Mary Jo Mulligan-Kehoe, Federico Corti, David D. Simon, Tyler D. Ross, John M. Rhodes, Thomas Z. Wang

Dartmouth Scholarship

Atherosclerotic plaque localization correlates with regions of disturbed flow in which endothelial cells (ECs) align poorly, whereas sustained laminar flow correlates with cell alignment in the direction of flow and resistance to atherosclerosis. We now report that in hypercholesterolemic mice, deletion of syndecan 4 (S4−/−) drastically increased atherosclerotic plaque burden with the appearance of plaque in normally resistant locations. Strikingly, ECs from the thoracic aortas of S4−/− mice were poorly aligned in the direction of the flow. Depletion of S4 in human umbilical vein endothelial cells (HUVECs) using shRNA also inhibited flow-induced alignment in vitro, which was rescued by re-expression …


E2f4 Regulatory Program Predicts Patient Survival Prognosis In Breast Cancer, Sari S. Khaleel, Erik H. Andrews, Matthew Ung, James Direnzo, Chao Chung Dec 2014

E2f4 Regulatory Program Predicts Patient Survival Prognosis In Breast Cancer, Sari S. Khaleel, Erik H. Andrews, Matthew Ung, James Direnzo, Chao Chung

Dartmouth Scholarship

Genetic and molecular signatures have been incorporated into cancer prognosis prediction and treatment decisions with good success over the past decade. Clinically, these signatures are usually used in early-stage cancers to evaluate whether they require adjuvant therapy following surgical resection. A molecular signature that is prognostic across more clinical contexts would be a useful addition to current signatures. We defined a signature for the ubiquitous tissue factor, E2F4, based on its shared target genes in multiple tissues. These target genes were identified by chromatin immunoprecipitation sequencing (ChIP-seq) experiments using a probabilistic method. We then computationally calculated the regulatory activity score …


Chip-Seq And In Vivo Transcriptome Analyses Of The Aspergillus Fumigatus Srebp Srba Reveals A New Regulator Of The Fungal Hypoxia Response And Virulence, Dawoon Chung, Bridget M. Barker, Charles C. Carey, Brittney Merriman Nov 2014

Chip-Seq And In Vivo Transcriptome Analyses Of The Aspergillus Fumigatus Srebp Srba Reveals A New Regulator Of The Fungal Hypoxia Response And Virulence, Dawoon Chung, Bridget M. Barker, Charles C. Carey, Brittney Merriman

Dartmouth Scholarship

The Aspergillus fumigatus sterol regulatory element binding protein (SREBP) SrbA belongs to the basic Helix-Loop-Helix (bHLH) family of transcription factors and is crucial for antifungal drug resistance and virulence. The latter phenotype is especially striking, as loss of SrbA results in complete loss of virulence in murine models of invasive pulmonary aspergillosis (IPA). How fungal SREBPs mediate fungal virulence is unknown, though it has been suggested that lack of growth in hypoxic conditions accounts for the attenuated virulence. To further understand the role of SrbA in fungal infection site pathobiology, chromatin immunoprecipitation followed by massively parallel DNA sequencing (ChIP-seq) was …


Role Of A Genetic Variant On The 15q25.1 Lung Cancer Susceptibility Locus In Smoking-Associated Nasopharyngeal Carcinoma, Xuemei Ji, Weidong Zhang, Jiang Gui, Xia Fan, Weiwei Zhang, Yafang Li, Guangyu An, Dakai Zhu, Qiang Hu Oct 2014

Role Of A Genetic Variant On The 15q25.1 Lung Cancer Susceptibility Locus In Smoking-Associated Nasopharyngeal Carcinoma, Xuemei Ji, Weidong Zhang, Jiang Gui, Xia Fan, Weiwei Zhang, Yafang Li, Guangyu An, Dakai Zhu, Qiang Hu

Dartmouth Scholarship

Background: The 15q25.1 lung cancer susceptibility locus, containing CHRNA5, could modify lung cancer susceptibility and multiple smoking related phenotypes. However, no studies have investigated the association between CHRNA5 rs3841324, which has been proven to have the highest association with CHRNA5 mRNA expression, and the risk of other smoking-associated cancers, except lung cancer. In the current study we examined the association between rs3841324 and susceptibility to smoking-associated nasopharyngeal carcinoma (NPC).

Methods: In this case-control study we genotyped the CHRNA5 rs3841324 polymorphism with 400 NPC cases and 491 healthy controls who were Han Chinese and frequency-matched by age (±5 years), gender, and …


Smarter Vaccine Design Will Circumvent Regulatory T Cell-Mediated Evasion In Chronic Hiv And Hcv Infection, Leonard Moise, Frances Terry, Andres H. Gutierrez, Ryan Tassone, Phyllis Losikoff, Stephen H. Gregory, Chris Bailey-Kellogg Oct 2014

Smarter Vaccine Design Will Circumvent Regulatory T Cell-Mediated Evasion In Chronic Hiv And Hcv Infection, Leonard Moise, Frances Terry, Andres H. Gutierrez, Ryan Tassone, Phyllis Losikoff, Stephen H. Gregory, Chris Bailey-Kellogg

Dartmouth Scholarship

Despite years of research, vaccines against HIV and HCV are not yet available, due largely to effective viral immunoevasive mechanisms. A novel escape mechanism observed in viruses that cause chronic infection is suppression of viral-specific effector CD4(+) and CD8(+) T cells by stimulating regulatory T cells (Tregs) educated on host sequences during tolerance induction. Viral class II MHC epitopes that share a T cell receptor (TCR)-face with host epitopes may activate Tregs capable of suppressing protective responses. We designed an immunoinformatic algorithm, JanusMatrix, to identify such epitopes and discovered that among human-host viruses, chronic viruses appear more human-like than viruses …


Inpp4b Suppresses Prostate Cancer Cell Invasion, Myles C. Hodgson, Elena I. Deryugina, Egla Suarez, Sandra M. Lopez, Dong Lin, Hui Xue, Ivan P. Gorlov Sep 2014

Inpp4b Suppresses Prostate Cancer Cell Invasion, Myles C. Hodgson, Elena I. Deryugina, Egla Suarez, Sandra M. Lopez, Dong Lin, Hui Xue, Ivan P. Gorlov

Dartmouth Scholarship

INPP4B and PTEN dual specificity phosphatases are frequently lost during progression of prostate cancer to metastatic disease. We and others have previously shown that loss of INPP4B expression correlates with poor prognosis in multiple malignancies and with metastatic spread in prostate cancer.

We demonstrate that de novo expression of INPP4B in highly invasive human prostate carcinoma PC-3 cells suppresses their invasion both in vitro and in vivo. Using global gene expression analysis, we found that INPP4B regulates a number of genes associated with cell adhesion, the extracellular matrix, and the cytoskeleton. Importantly, de novo expressed INPP4B suppressed the proinflammatory chemokine …