Medicine and Health Sciences Commons^™

Lactate Dehydrogenase In Toxoplasma Gondii Controls Virulence, Bradyzoite Differentiation, And Chronic Infection, Abdelbaset E. Abdelbaset, Barbara A. Fox, Mohamed H. Karram, Mahmoud R. Abd Ellah, David J. Bzik, Makoto Igarashi

Dartmouth Scholarship

In the asexual stages, Toxoplasma gondii stage converts between acute phase rapidly replicating tachyzoites and chronic phase slowly dividing bradyzoites. Correspondingly, T. gondii differentially expresses two distinct genes and isoforms of the lactate dehydrogenase enzyme, expressing LDH1 exclusively in the tachyzoite stage and LDH2 preferentially in the bradyzoite stage. LDH catalyzes the interconversion of pyruvate and lactate in anaerobic growth conditions and is utilized for energy supply, however, the precise role of LDH1 and LDH2 in parasite biology in the asexual stages is still unclear. Here, we investigated the biological role of LDH1 and LDH2 in the asexual stages, …

Neutralization Of Diverse Human Cytomegalovirus Strains Conferred By Antibodies Targeting Viral Gh/Gl/Pul128-131 Pentameric Complex, Sha Ha, Fengsheng Li, Matthew C. Troutman, Daniel C. Freed, Aimin Tang, John W. Loughney, Dai Wang, I-Ming Wang, Josef Vlasak, David C. Nickle, Richard R. Rustandi, Melissa Hamm, Pete A. Dephillips, Ningyan Zhang, Jason S. Mclellan, Stuart P. Adler, Michael A. Mcvoy, Zhiqiang An, Tong-Ming Fu

Dartmouth Scholarship

Human cytomegalovirus (HCMV) is the leading cause of congenital viral infection, and developing a prophylactic vaccine is of high priority to public health. We recently reported a replication-defective human cytomegalovirus with restored pentameric complex glycoprotein H (gH)/gL/pUL128-131 for prevention of congenital HCMV infection. While the quantity of vaccine-induced antibody responses can be measured in a viral neutralization assay, assessing the quality of such responses, including the ability of vaccine-induced antibodies to cross-neutralize the field strains of HCMV, remains a challenge. In this study, with a panel of neutralizing antibodies from three healthy human donors with natural HCMV infection or a …

Susceptibility Of Anopheles Gambiae To Insecticides Used For Malaria Vector Control In Rwanda, Emmanuel Hakizimana, Corine Karema, Dunia Munyakanage, Gad Iranzi, John Githure, Jon Eric Tongren, Willem Takken, Agnes Binagwaho, Constantianus J.M. Koenraadt

Dartmouth Scholarship

Background:

The widespread emergence of resistance to pyrethroids is a major threat to the gains made in malaria control. To monitor the presence and possible emergence of resistance against a variety of insecticides used for malaria control in Rwanda, nationwide insecticide resistance surveys were conducted in 2011 and 2013.

Methods:

Larvae of Anopheles gambiae sensu lato mosquitoes were collected in 12 sentinel sites throughout Rwanda. These were reared to adults and analysed for knock-down and mortality using WHO insecticide test papers with standard diagnostic doses of the recommended insecticides. A sub-sample of tested specimens was analysed for the presence of …

Optical Tracer Size Differences Allow Quantitation Of Active Pumping Rate Versus Stokes–Einstein Diffusion In Lymphatic Transport, Alisha V. Dsouza, Kayla Marra, Jason R. Gunn, Kimberley S. Samkoe, Brian W. Pogue

Dartmouth Scholarship

Lymphatic uptake of interstitially administered agents occurs by passive convective–diffusive inflow driven by interstitial concentration and pressure, while the downstream lymphatic transport is facilitated by active propulsive contractions of lymphatic vessel walls. Near-infrared fluorescence imaging in mice was used to measure these central components of lymphatic transport for the first time, using two different-sized molecules––methylene blue (MB) and fluorescence-labeled antibody immunoglobulin G (IgG)-IRDye 680RD. This work confirms the hypothesis that lymphatic passive inflow and active propulsion rates can be separated based upon the relative differences in Stokes–Einstein diffusion coefficient. This coefficient specifically affects the passive-diffusive uptake when the interstitial volume …

Phenotypes Associated With Knockouts Of Eight Dense Granule Gene Loci (Gra2-9) In Virulent Toxoplasma Gondii, Leah M. Rommereim, Valeria Bellini, Barbara A. Fox, Graciane Pètre, Camille Rak, Bastien Touquet, Delphine Aldebert, Jean-François Dubremetz, Marie-France Cesbron-Delauw, Corinne Mercier, David J. Bzik

Dartmouth Scholarship

Toxoplasma gondii actively invades host cells and establishes a parasitophorous vacuole (PV) that accumulates many proteins secreted by the dense granules (GRA proteins). To date, at least 23 GRA proteins have been reported, though the function(s) of most of these proteins still remains unknown. We targeted gene knockouts at ten GRA gene loci (GRA1-10) to investigate the cellular roles and essentiality of these classical GRA proteins during acute infection in the virulent type I RH strain. While eight of these genes (GRA2-9) were successfully knocked out, targeted knockouts at the GRA1 and GRA10 loci were not …

Secretion Of Rhoptry And Dense Granule Effector Proteins By Nonreplicating Toxoplasma Gondii Uracil Auxotrophs Controls The Development Of Antitumor Immunity, Barbara A. Fox, Kiah L. Sanders, Leah M. Rommereim, Rebekah B. Guevara, David J. Bzik

Dartmouth Scholarship

Nonreplicating type I uracil auxotrophic mutants of Toxoplasma gondii possess a potent ability to activate therapeutic immunity to established solid tumors by reversing immune suppression in the tumor microenvironment. Here we engineered targeted deletions of parasite secreted effector proteins using a genetically tractable Δku80 vaccine strain to show that the secretion of specific rhoptry (ROP) and dense granule (GRA) proteins by uracil auxotrophic mutants of T. gondii in conjunction with host cell invasion activates antitumor immunity through host responses involving CD8α⁺ dendritic cells, the IL-12/interferon-gamma (IFN-γ) T_H1 axis, as well as CD4⁺ and CD8 …

Vegfr2 Py949 Signalling Regulates Adherens Junction Integrity And Metastatic Spread, Xiujuan Li, Narendra Padhan, Elisabet O. Sjöström, Francis P. Roche, Chiara Testini, Naoki Honkura, Miguel Sáinz-Jaspeado, Emma Gordon, Katie Bentley, Andrew Philippides, Vladimir Tolmachev, Elisabetta Dejana, Radu V. Stan, Dietmar Vestweber, Kurt Ballmer-Hofer, Christer Betsholtz, Kristian Pietras, Leif Jansson, Lena Claesson-Welsh

Dartmouth Scholarship

The specific role of VEGFA-induced permeability and vascular leakage in physiology and pathology has remained unclear. Here we show that VEGFA-induced vascular leakage depends on signalling initiated via the VEGFR2 phosphosite Y949, regulating dynamic c-Src and VE-cadherin phosphorylation. Abolished Y949 signalling in the mouse mutant Vegfr2^Y949F/Y949F leads to VEGFA-resistant endothelial adherens junctions and a block in molecular extravasation. Vessels in Vegfr2^Y949F/Y949F mice remain sensitive to inflammatory cytokines, and vascular morphology, blood pressure and flow parameters are normal. Tumour-bearing Vegfr2^Y949F/Y949F mice display reduced vascular leakage and oedema, improved response to chemotherapy and, importantly, reduced metastatic spread. The inflammatory …

Smn Protein Can Be Reliably Measured In Whole Blood With An Electrochemiluminescence (Ecl) Immunoassay: Implications For Clinical Trials, Phillip Zaworski, Katharine M. Von Herrmann, Shannon Taylor, Sara S. Sunshine, Kathleen Mccarthy, Nicole Risher, Tara Newcomb, Marla Weetall, Thomas W. Prior, Kathryn J. Swoboda, Karen S. Chen, Sergey Paushkin

Dartmouth Scholarship

Spinal muscular atrophy (SMA) is caused by defects in the survival motor neuron 1 (SMN1) gene that encodes survival motor neuron (SMN) protein. The majority of therapeutic approaches currently in clinical development for SMA aim to increase SMN protein expression and there is a need for sensitive methods able to quantify increases in SMN protein levels in accessible tissues. We have developed a sensitive electrochemiluminescence (ECL)-based immunoassay for measuring SMN protein in whole blood with a minimum volume requirement of 5μL. The SMN-ECL immunoassay enables accurate measurement of SMN in whole blood and other tissues. Using the assay, …

Cddo-Me Redirects Activation Of Breast Tumor Associated Macrophages, Michael S. Ball, Emilie P. Shipman, Hyunjung Kim, Karen T. Liby, Patricia A. Pioli

Dartmouth Scholarship

Tumor-associated macrophages can account for up to 50% of the tumor mass in breast cancer patients and high TAM density is associated with poor clinical prognosis. Because TAMs enhance tumor growth, development, and metastatic potential, redirection of TAM activation may have significant therapeutic benefit. Our studies in primary human macrophages and murine breast TAMs suggest that the synthetic oleanane triterpenoid CDDO-methyl ester (CDDO-Me) reprograms the activation profile of TAMs from tumor-promoting to tumor-inhibiting. We show that CDDO-Me treatment inhibits expression of IL-10 and VEGF in stimulated human M2 macrophages and TAMs but increases expression of TNF-α and IL-6. Surface expression …

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 …

Regulation Of Stem Cell Proliferation And Cell Fate Specification By Wingless/Wnt Signaling Gradients Enriched At Adult Intestinal Compartment Boundaries, Ai Tian, Hassina Benchabane, Zhenghan Wang, Yashi Ahmed

Dartmouth Scholarship

Intestinal stem cell (ISC) self-renewal and proliferation are directed by Wnt/β-catenin signaling in mammals, whereas aberrant Wnt pathway activation in ISCs triggers the development of human colorectal carcinoma. Herein, we have utilized the Drosophila midgut, a powerful model for ISC regulation, to elucidate the mechanisms by which Wingless (Wg)/Wnt regulates intestinal homeostasis and development. We provide evidence that the Wg signaling pathway, activation of which peaks at each of the major compartment boundaries of the adult intestine, has essential functions. Wg pathway activation in the intestinal epithelium is required not only to specify cell fate near compartment boundaries during development, …

Analyzing Clustered Data: Why And How To Account For Multiple Observations Nested Within A Study Participant?, Erika L. Moen, Catherine J. Fricano-Kugler, Bryan W. Luikart, A. James O’Malley

Dartmouth Scholarship

A conventional study design among medical and biological experimentalists involves col- lecting multiple measurements from a study subject. For example, experiments utilizing mouse models in neuroscience often involve collecting multiple neuron measurements per mouse to increase the number of observations without requiring a large number of mice. This leads to a form of statistical dependence referred to as clustering. Inappropriate analy- ses of clustered data have resulted in several recent critiques of neuroscience research that suggest the bar for statistical analyses within the field is set too low. We compare naïve ana- lytical approaches to marginal, fixed-effect, and mixed-effect models …

Non-Alcoholic Fatty Liver Disease Induces Signs Of Alzheimer’S Disease (Ad) In Wild-Type Mice And Accelerates Pathological Signs Of Ad In An Ad Model, Do-Geun Kim, Antje Krenz, Leon E. Toussaint, Kirk J. Maurer

Dartmouth Scholarship

Background: Non-alcoholic fatty liver disease (NAFLD) is a chronic liver disease afflicting about one third of the world's population and 30 % of the US population. It is induced by consumption of high-lipid diets and is characterized by liver inflammation and subsequent liver pathology. Obesity and consumption of a high-fat diet are known to increase the risk of Alzheimer's disease (AD). Here, we investigated NAFLD-induced liver inflammation in the pathogenesis of AD.

Methods: WT and APP-Tg mice were fed with a standard diet (SD) or a high-fat diet (HFD) for 2, 5 months, or 1 year to induce NAFLD. Another …

Integrative Analysis Of Breast Cancer Reveals Prognostic Haematopoietic Activity And Patient-Specific Immune Response Profiles, Frederick S. Varn, Erik H. Andrews, David W. Mullins, Chao Cheng

Dartmouth Scholarship

Transcriptional programmes active in haematopoietic cells enable a variety of functions including dedifferentiation, innate immunity and adaptive immunity. Understanding how these programmes function in the context of cancer can provide valuable insights into host immune response, cancer severity and potential therapy response. Here we present a method that uses the transcriptomes of over 200 murine haematopoietic cells, to infer the lineage-specific haematopoietic activity present in human breast tumours. Correlating this activity with patient survival and tumour purity reveals that the transcriptional programmes of many cell types influence patient prognosis and are found in environments of high lymphocytic infiltration. Collectively, these …

Framework For Hyperspectral Image Processing And Quantification For Cancer Detection During Animal Tumor Surgery, Guolan Lu, Dongsheng Wang, Xulei Qin, Luma Halig, Susan Muller, Hongzheng Zhang, Amy Chen, Brian W. Pogue, Zhuo G. Chen

Dartmouth Scholarship

Hyperspectral imaging (HSI) is an imaging modality that holds strong potential for rapid cancer detection during image-guided surgery. But the data from HSI often needs to be processed appropriately in order to extract the maximum useful information that differentiates cancer from normal tissue. We proposed a framework for hyperspectral image processing and quantification, which includes a set of steps including image preprocessing, glare removal, feature extraction, and ultimately image classification. The framework has been tested on images from mice with head and neck cancer, using spectra from 450- to 900-nm wavelength. The image analysis computed Fourier coefficients, normalized reflectance, mean, …

Nucleus Accumbens Deep Brain Stimulation In A Rat Model Of Binge Eating, W. T. Doucette, J. Y. Khokhar, A. I. Green

Dartmouth Scholarship

Binge eating (BE) is a difficult-to-treat behavior with high relapse rates, thus complicating several disorders including obesity. In this study, we tested the effects of high-frequency deep brain stimulation (DBS) in a rodent model of BE. We hypothesized that BE rats receiving high-frequency DBS in the nucleus accumbens (NAc) core would have reduced binge sizes compared with sham stimulation in both a 'chronic BE' model as well as in a 'relapse to chronic BE' model. Male Sprague-Dawley rats (N=18) were implanted with stimulating electrodes in bilateral NAc core, and they received either active stimulation (N=12) or sham stimulation (N=6) for …

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 …

Systematic Analysis Of Hematopoietic Gene Expression Profiles For Prognostic Prediction In Acute Myeloid Leukemia, Frederick S. Varn, Erik H. Andrews, Chao Cheng

Dartmouth Scholarship

Acute myeloid leukemia (AML) is a hematopoietic disorder initiated by the leukemogenic transformation of myeloid cells into leukemia stem cells (LSCs). Preexisting gene expression programs in LSCs can be used to assess their transcriptional similarity to hematopoietic cell types. While this relationship has previously been examined on a small scale, an analysis that systematically investigates this relationship throughout the hematopoietic hierarchy has yet to be implemented. We developed an integrative approach to assess the similarity between AML patient tumor profiles and a collection of 232 murine hematopoietic gene expression profiles compiled by the Immunological Genome Project. The resulting lineage similarity …

Pleiotropic Effects Of Immune Responses Explain Variation In The Prevalence Of Fibroproliferative Diseases, Shirley B. Russell, Joan C. Smith, Minjun Huang, Joel S. Trupin, Scott M. Williams

Dartmouth Scholarship

Many diseases are differentially distributed among human populations. Differential selection on genetic variants in ancestral environments that coincidentally predispose to disease can be an underlying cause of these unequal prevalence patterns. Selected genes may be pleiotropic, affecting multiple phenotypes and resulting in more than one disease or trait. Patterns of pleiotropy may be helpful in understanding the underlying causes of an array of conditions in a population. For example, several fibroproliferative diseases are more prevalent and severe in populations of sub-Saharan ancestry. We propose that this disparity is due to selection for an enhanced Th2 response that confers resistance to …

Dendritic Cell Autophagy Contributes To Herpes Simplex Virus-Driven Stromal Keratitis And Immunopathology, Yike Jiang, Xiaotang Yin, Patrick M. Stuart, David A. Leib

Dartmouth Scholarship

Herpetic stromal keratitis (HSK) is a blinding ocular disease that is initiated by HSV-1 and characterized by chronic inflammation in the cornea. Although HSK immunopathology of the cornea is well documented in animal models, events preceding this abnormal inflammatory cascade are poorly understood. In this study, we have examined the activation of pathological CD4T cells in the development of HSK. Dendritic cell autophagy (DC-autophagy) is an important pathway regulating ma- jor histocompatibility complex class II (MHCII)-dependent antigen presentation and proper CD4T cell activation during infectious diseases. Using DC-autophagy-deficient mice, we found that DC-autophagy significantly and specifically contributes to HSK disease …

The Fungal Exopolysaccharide Galactosaminogalactan Mediates Virulence By Enhancing Resistance To Neutrophil Extracellular Traps, Mark J. Lee, Hong Liu, Bridget M. Barker, Brendan D. Snarr, Fabrice M. Gravelat, Qusai Al Abdallah, Christina Gavino, Shane R. Baistrocchi, Hanna Ostapska, Tianli Xiao, Benjamin Ralph, Norma V. Solis, Melanie Lehoux, Stefanie D. Baptista, Arsa Thammahong

Dartmouth Scholarship

Of the over 250 Aspergillus species, Aspergillus fumigatus accounts for up to 80% of invasive human infections. A. fumigatus produces galactosaminogalactan (GAG), an exopolysaccharide composed of galactose and N-acetyl-galactosamine (GalNAc) that mediates adherence and is required for full virulence. Less pathogenic Aspergillus species were found to produce GAG with a lower GalNAc content than A. fumigatus and expressed minimal amounts of cell wall-bound GAG. Increasing the GalNAc content of GAG of the minimally pathogenic A. nidulans, either through overexpression of the A. nidulans epimerase UgeB or by heterologous expression of the A. fumigatus epimerase …

Genestation 1.0: A Synthetic Resource Of Diverse Evolutionary And Functional Genomic Data For Studying The Evolution Of Pregnancy-Associated Tissues And Phenotypes, Mara Kim, Brian A. Cooper, Rohit Venkat, Julie B. Phillips, Haley R. Eidem, Jibril Hirbo, Sashank Nutakki, Scott M. Williams, Louis J. Muglia, J. Anthony Capra, Kenneth Petren, Patrick Abbot, Antonis Rokas, Kriston L. Mcgary

Dartmouth Scholarship

Mammalian gestation and pregnancy are fast evolving processes that involve the interaction of the fetal, maternal and paternal genomes. Version 1.0 of the GEneSTATION database (http://genestation.org) integrates diverse types of omics data across mammals to advance understanding of the genetic basis of gestation and pregnancy-associated phenotypes and to accelerate the translation of discoveries from model organisms to humans. GEneSTATION is built using tools from the Generic Model Organism Database project, including the biology-aware database CHADO, new tools for rapid data integration, and algorithms that streamline synthesis and user access. GEneSTATION contains curated life history information on pregnancy and …

Parasite Manipulation Of The Invariant Chain And The Peptide Editor H2-Dm Affects Major Histocompatibility Complex Class Ii Antigen Presentation During Toxoplasma Gondii Infection, Louis-Philippe Leroux, Manami Nishi, Sandy El-Hage, Barbara A. Fox, David I Bzik, Florence Dzierszinsk

Dartmouth Scholarship

Toxoplasma gondii is an obligate intracellular protozoan parasite. This apicomplexan is the causative agent of toxoplasmosis, a leading cause of central nervous system disease in AIDS. It has long been known that T. gondii interferes with major histocompatibility complex class II (MHC-II) antigen presentation to attenuate CD4(+) T cell responses and establish persisting infections. Transcriptional downregulation of MHC-II genes by T. gondii was previously established, but the precise mechanisms inhibiting MHC-II function are currently unknown. Here, we show that, in addition to transcriptional regulation of MHC-II, the parasite modulates the expression of key components of the MHC-II antigen presentation pathway, …

Eisosomes Provide Membrane Reservoirs For Rapid Expansion Of The Yeast Plasma Membrane, Ruth Kabeche, Louisa Howard, James B. Moseley

Dartmouth Scholarship

Cell surface area rapidly increases during mechanical and hypoosmotic stresses. Such expansion of the plasma membrane requires 'membrane reservoirs' that provide surface area and buffer membrane tension, but the sources of this membrane remain poorly understood. In principle, the flattening of invaginations and buds within the plasma membrane could provide this additional surface area, as recently shown for caveolae in animal cells. Here, we used microfluidics to study the rapid expansion of the yeast plasma membrane in protoplasts, which lack the rigid cell wall. To survive hypoosmotic stress, yeast cell protoplasts required eisosomes, protein-based structures that generate long invaginations at …

Development And Validation Of An Epitope Prediction Tool For Swine (Pigmatrix) Based On The Pocket Profile Method, Andres H. Gutiérrez, William D. Martin, Chris Bailey-Kellogg, Frances Terry, Leonard Moise, Anee S. De Groot

Dartmouth Scholarship

Background: T cell epitope prediction tools and associated vaccine design algorithms have accelerated the development of vaccines for humans. Predictive tools for swine and other food animals are not as well developed, primarily because the data required to develop the tools are lacking. Here, we overcome a lack of T cell epitope data to construct swine epitope predictors by systematically leveraging available human information. Applying the “pocket profile method ”, we use sequence and structural similarities in the binding pockets of human and swine major histocompatibility complex proteins to infer Swine Leukocyte Antigen (SLA) peptide binding preferences. We developed epitope-prediction …

Targeting Ezh2 Regulates Tumor Growth And Apoptosis Through Modulating Mitochondria Dependent Cell-Death Pathway In Hnscc, Xuan Zhou, Yu Ren, Lingping Kong, Guoshuai Cai, Shanshan Sun, Wangzhao Song, Yu Wang, Rui Jin, Lisha Qi, Mei Mei

Dartmouth Scholarship

EZH2 is a negative prognostic factor and is overexpressed or activated in most human cancers including head and neck squamous cell carcinoma (HNSCC). Analysis of The Cancer Genome Atlas (TCGA) HNSCC data indicated that EZH2 over-expression was associated with high tumor grade and conferred poor prognosis. EZH2 inhibition triggered cell apoptosis, cell cycle arrest and decreased cell growth in vitro. MICU1 (mitochondrial calcium uptake1) was shown to be down regulated when EZH2 expression was inhibited in HNSCC. When the EZH2 and MICU1 were inhibited, HNSCC cells became susceptible to cell cycle arrest and apoptosis. Mitochondrial membrane potential and cytosolic Ca2+ …

Rna-Seq Analysis Of Differential Splice Junction Usage And Intron Retentions By Dexseq, Yafang Li, Xiayu Rao, William W. Mattox, Christopher I. Amos, Bin Liu

Dartmouth Scholarship

Alternative splicing is an important biological process in the generation of multiple functional transcripts from the same genomic sequences. Differential analysis of splice junctions (SJs) and intron retentions (IRs) is helpful in the detection of alternative splicing events. In this study, we conducted differential analysis of SJs and IRs by use of DEXSeq, a Bioconductor package originally designed for differential exon usage analysis in RNA-seq data analysis. We set up an analysis pipeline including mapping of RNA-seq reads, the preparation of count tables of SJs and IRs as the input files, and the differential analysis in DEXSeq. We analyzed the …

Role Of The Dna Sensor Sting In Protection From Lethal Infection Following Corneal And Intracerebral Challenge With Herpes Simplex Virus 1, Zachary M. Parker, Aisling A. Murphy, David. A. Leib

Dartmouth Scholarship

STING is a protein in the cytosolic DNA and cyclic dinucleotide sensor pathway that is critical for the initiation of innate responses to infection by various pathogens. Consistent with this, herpes simplex virus 1 (HSV-1) causes invariable and rapid lethality in STING-deficient (STING(-/-)) mice following intravenous (i.v.) infection. In this study, using real-time bioluminescence imaging and virological assays, as expected, we demonstrated that STING(-/-) mice support greater replication and spread in ocular tissues and the nervous system. In contrast, they did not succumb to challenge via the corneal route even with high titers of a virus that was routinely lethal …

Logarithmic Intensity Compression In Fluorescence Guided Surgery Applications, Alisha V. Dsouza, Huiyun Lin, Jason Gunn, Brian W. Pogue

Dartmouth Scholarship

The use of fluorescence video imaging to guide surgery is rapidly expanding, and improvements in camera readout dynamic range have not matched display capabilities. Logarithmic intensity compression is a fast, single-step mapping technique that can map the useable dynamic range of high-bit fluorescence images onto the typical 8-bit display and potentially be a variable dynamic contrast enhancement tool. We demonstrate a ∼4.6  times improvement in image quality quantified by image entropy and a dynamic range reduction by a factor of ∼380 by the use of log-compression tools in processing in vivo fluorescence images.

Numerical Chromosomal Instability Mediates Susceptibility To Radiation Treatment, Samuel F. Bakhoum, Lilian Kabeche, Matthew D. Wood, Christopher D. Laucius

Dartmouth Scholarship

The exquisite sensitivity of mitotic cancer cells to ionizing radiation (IR) underlies an important rationale for the widely used fractionated radiation therapy. However, the mechanism for this cell cycle-dependent vulnerability is unknown. Here we show that treatment with IR leads to mitotic chromosome segregation errors in vivo and long-lasting aneuploidy in tumour-derived cell lines. These mitotic errors generate an abundance of micronuclei that predispose chromosomes to subsequent catastrophic pulverization thereby independently amplifying radiation-induced genome damage. Experimentally suppressing whole-chromosome missegregation reduces downstream chromosomal defects and significantly increases the viability of irradiated mitotic cells. Further, orthotopically transplanted human glioblastoma tumours in which …