Medicine and Health Sciences Commons^™

Review Of Biomedical Čerenkov Luminescence Imaging Applications, Kaveh Tanha, Ali Mahmoud Pashazadeh, Brian W. Pogue

Dartmouth Scholarship

Čerenkov radiation is a fascinating optical signal, which has been exploited for unique diagnostic biological sensing and imaging, with significantly expanded use just in the last half decade. Čerenkov Luminescence Imaging (CLI) has desirable capabilities for niche applications, using specially designed measurement systems that report on radiation distributions, radiotracer and nanoparticle concentrations, and are directly applied to procedures such as medicine assessment, endoscopy, surgery, quality assurance and dosimetry. When compared to the other imaging tools such as PET and SPECT, CLI can have the key advantage of lower cost, higher throughput and lower imaging time. CLI can also provide imaging …

Association Between Arsenic Exposure From Drinking Water And Longitudinal Change In Blood Pressure Among Heals Cohort Participants, Jieying Jiang, Mengling Liu, Faruque Parvez, Binhuan Wang, Fen Wu, Mahbub Eunus, Sripal Bangalore, Jonathan D. Newman, Alauddin Ahmed, Tariqul Islam, Muhammed Rakibuz-Zaman, Rabiul Hasan, Golam Sarwar, Diane Levy, Vesna Slavkovich, Maria Argos, Molly Scannell Bryan, Shohreh F. Farzan, Richard B. Hayes, Joseph H. Graziano, Habibul Ahsan, Yu Chen

Dartmouth Scholarship

Background:

Cross-sectional studies have shown associations between arsenic exposure and prevalence of high blood pressure; however, studies examining the relationship of arsenic exposure with longitudinal changes in blood pressure are lacking.

Method:

We evaluated associations of arsenic exposure in relation to longitudinal change in blood pressure in 10,853 participants in the Health Effects of Arsenic Longitudinal Study (HEALS). Arsenic was measured in well water and in urine samples at baseline and in urine samples every 2 years after baseline. Mixed-effect models were used to estimate the association of baseline well and urinary creatinine-adjusted arsenic with annual change in blood pressure …

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 …

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 …

Addressing Therapeutic Options For Ebola Virus Infection In Current And Future Outbreaks, Azizul Haque, Didier Hober, Joel Blondiaux

Dartmouth Scholarship

Ebola virus can cause severe hemorrhagic disease with high fatality rates. Currently, no specific therapeutic agent or vaccine has been approved for treatment and prevention of Ebola virus infection of humans. Although the number of Ebola cases has fallen in the last few weeks, multiple outbreaks of Ebola virus infection and the likelihood of future exposure highlight the need for development and rapid evaluation of pre- and postexposure treatments. Here, we briefly review the existing and future options for anti-Ebola therapy, based on the data coming from rare clinical reports, studies on animals, and results from in vitro models. We …

Dna Methylation In Ductal Carcinoma In Situ Related With Future Development Of Invasive Breast Cancer, Kevin C. Johnson, Devin C. Koestler, Thomas Fleischer, Panpan Chen, Erik G. Jenson, Jonathan D. Marotti, Tracy Onega, Vessela N. Kristenen, Brock C. Christensen

Dartmouth Scholarship

Background: Ductal carcinoma in situ (DCIS) is a heterogeneous, pre-invasive lesion associated with an increased risk for future invasive ductal carcinoma. However, accurate risk stratification for development of invasive disease and appropriate treatment decisions remain clinical challenges. DNA methylation alterations are early events in the progression of cancer and represent emerging molecular markers that may predict invasive recurrence more accurately than traditional measures of DCIS prognosis.

Results: We measured DNA methylation using the Illumina HumanMethylation450K array of estrogen-receptor positive DCIS (n = 40) and adjacent-normal (n = 15) tissues from subjects in the New Hampshire Mammography Network longitudinal breast imaging …

Trustworthy Guidelines – Excellent; Customized Care Tools – Even Better, Glyn Elwyn, Casey Quinlan, Albert Mulley, Thomas Agoritsas, Per Olav Vandvik, Gordon Guyatt

Dartmouth Scholarship

Background:

The ability to do online searches for health information has led to concerns that patients find the results confusing and that they often lead to expectations for treatments that have little supportive evidence. At the same time, the science of summarizing research evidence has advanced to the point where it is increasingly possible to quantify treatment tradeoffs and to describe the balance between harms and benefits for individual patients.

Discussion:

Trustworthy clinical practice guidelines provide evidence-based recommendations to health care practitioners based on assessments of study-level averages. In an effort to customize the use of evidence and ensure that …

Genome-Wide Meta-Analysis In Alopecia Areata Resolves Hla Associations And Reveals Two New Susceptibility Loci, Regina C. Betz, Lynn Petukhova, Stephan Ripke, Hailiang Huang, Androniki Menelaou, Silke Redeler, Tim Becker, Stefanie Heilmann, Tarek Yamany, Madeleine Duvic, Maria Hordinsky, David Norris, Vera H. Price, Julian Mackay-Wiggan, Annemieke De Jong, Gina M. Destefano, Susanne Moebus, Markus Böhm, Ulrike Blume-Peytavi, Hans Wolff, Gerhard Lutz, Roland Kruse, Li Bian, Christopher I. Amos

Dartmouth Scholarship

Alopecia areata (AA) is a prevalent autoimmune disease with ten known susceptibility loci. Here we perform the first meta-analysis in AA by combining data from two genome-wide association studies (GWAS), and replication with supplemented ImmunoChip data for a total of 3,253 cases and 7,543 controls. The strongest region of association is the MHC, where we fine-map 4 independent effects, all implicating HLA-DR as a key etiologic driver. Outside the MHC, we identify two novel loci that exceed statistical significance, containing ACOXL/BCL2L11(BIM) (2q13); GARP (LRRC32) (11q13.5), as well as a third nominally significant region SH2B3(LNK)/ ATXN2 (12q24.12). Candidate susceptibility gene expression …

Registered Report: Biomechanical Remodeling Of The Microenvironment By Stromal Caveolin-1 Favors Tumor Invasion And Metastasis, Steven Fiering, Lay-Hong Ang, Judith Lacoste, Tim D. Smith, Erin Griner

Dartmouth Scholarship

The Reproducibility Project: Cancer Biology seeks to address growing concerns about reproducibility in scientific research by conducting replicating selected results from a number of high-profile papers in the field of cancer biology. The papers, which were published between 2010 and 2012 were selected on the basis of citations and Altimetric scores (Errington et al., 2014). This Registered report describes the proposed replication plan of key experiments from ‘Biomechanical remodeling of the microenvironment by stromal caveolin-1 favors tumor invasion and metastasis’ by Goetz and colleagues, published in Cell in 2011 (Goetz et al., 2011). The key experiments …

New York State: Comparison Of Treatment Outcomes For Unruptured Cerebral Aneurysms Using An Instrumental Variable Analysis, Kimon Bekelis, Symeon Missios, Shannon Coy, Robert J. Singer, Todd A. Mackenzie

Dartmouth Scholarship

Background:

There is wide regional variation in the predominant treatment for unruptured cerebral aneurysms. We investigated the association of elective surgical clipping and endovascular coiling with mortality, readmission rate, length of stay, and discharge to rehabilitation.

Methods and Results:

We performed a cohort study involving patients with unruptured cerebral aneurysms, who underwent surgical clipping or endovascular coiling from 2009 to 2013 and were registered in the Statewide Planning and Research Cooperative System database. An instrumental variable analysis was used to investigate the association of treatment technique with outcomes. Of the 4643 patients undergoing treatment, 3190 (68.7%) underwent coiling, and 1453 …

Characterization Of A Prefusion-Specific Antibody That Recognizes A Quaternary, Cleavage-Dependent Epitope On The Rsv Fusion Glycoprotein, Morgan S.A Gilman, Syed M. Moin, Vicente Mas, Man Chen, Nita K. Patel, Kari Kramer, Qing Zhu, Stephanie C. Kabeche, Azad Kumar, Concepción Palomo, Tim Beaumont, Ulrich Baxa, Nancy D. Ulbrandt, José A. Melero, Barney S. Graham, Jason S. Mclellan

Dartmouth Scholarship

Prevention efforts for respiratory syncytial virus (RSV) have been advanced due to the recent isolation and characterization of antibodies that specifically recognize the prefusion conformation of the RSV fusion (F) glycoprotein. These potently neutralizing antibodies are in clinical development for passive prophylaxis and have also aided the design of vaccine antigens that display prefusion-specific epitopes. To date, prefusion-specific antibodies have been shown to target two antigenic sites on RSV F, but both of these sites are also present on monomeric forms of F. Here we present a structural and functional characterization of human antibody AM14, which potently neutralized laboratory strains …

Targeting Neddylation Induces Dna Damage And Checkpoint Activation And Sensitizes Chronic Lymphocytic Leukemia B Cells To Alkylating Agents, C Paiva, J C. Godbersen, A Berger, J R. Brown, A V. Danilov

Dartmouth Scholarship

Microenvironment-mediated upregulation of the B-cell receptor (BCR) and nuclear factor-κB (NF-κB) signaling in CLL cells resident in the lymph node and bone marrow promotes apoptosis evasion and clonal expansion. We recently reported that MLN4924 (pevonedistat), an investigational agent that inhibits the NEDD8-activating enzyme (NAE), abrogates stromal-mediated NF-κB pathway activity and CLL cell survival. However, the NAE pathway also assists degradation of multiple other substrates. MLN4924 has been shown to induce DNA damage and cell cycle arrest, but the importance of this mechanism in primary neoplastic B cells has not been studied. Here we mimicked the lymph node microenvironment using CD40 …

Selective Involvement Of The Checkpoint Regulator Vista In Suppression Of B-Cell, But Not T-Cell, Responsiveness By Monocytic Myeloid-Derived Suppressor Cells From Mice Infected With An Immunodeficiency-Causing Retrovirus, Kathy A. Green, Li Wang, Randolph J. Noelle, William R. Green

Dartmouth Scholarship

Inhibition of T-cell responses in tumor microenvironments by myeloid-derived suppressor cells (MDSCs) is widely accepted. We demonstrated augmentation of monocytic MDSCs whose suppression of not only T-cell, but also B-cell, responsiveness paralleled the immunodeficiency during LP-BM5 retrovirus infection. MDSCs inhibited T cells by inducible nitric oxide synthase (iNOS)/nitric oxide (NO), but uniquely, inhibition of B cells was ~50% dependent each on iNOS/NO and the MDSC-expressed negative-checkpoint regulator VISTA. Blockade with a combination of iNOS/NO and VISTA caused additive or synergistic abrogation of MDSC-mediated suppression of B-cell responsiveness.

Neuronal Interferon Signaling Is Required For Protection Against Herpes Simplex Virus Replication And Pathogenesis, Pamela C. Rosato, David A. Leib

Dartmouth Scholarship

Interferon (IFN) responses are critical for controlling herpes simplex virus 1 (HSV-1). The importance of neuronal IFN signaling in controlling acute and latent HSV-1 infection remains unclear. Compartmentalized neuron cultures revealed that mature sensory neurons respond to IFNβ at both the axon and cell body through distinct mechanisms, resulting in control of HSV-1. Mice specifically lacking neural IFN signaling succumbed rapidly to HSV-1 corneal infection, demonstrating that IFN responses of the immune system and non-neuronal tissues are insufficient to confer survival following virus challenge. Furthermore, neurovirulence was restored to an HSV strain lacking the IFN-modulating gene, γ34.5, despite its expected …

A Self-Lysis Pathway That Enhances The Virulence Of A Pathogenic Bacterium, Kirsty A. Mcfarland, Emily L. Dolben, Michele Leroux, Tracy K. Kambara, Kathryn Ramsey, Robin Kirkpatrick, Joseph Mougous, Deborah Hogan, Simon Dove

Dartmouth Scholarship

In mammalian cells, programmed cell death (PCD) plays important roles in development, in the removal of damaged cells, and in fighting bacterial infections. Although widespread among multicellular organisms, there are relatively few documented instances of PCD in bacteria. Here we describe a potential PCD pathway in Pseudomonas aeruginosa that enhances the ability of the bacterium to cause disease in a lung infection model. Activation of the system can occur in a subset of cells in response to DNA damage through cleavage of an essential transcription regulator we call AlpR. Cleavage of AlpR triggers a cell lysis program through de-repression of …

Placental Dna Methylation Related To Both Infant Toenail Mercury And Adverse Neurobehavioral Outcomes, Jennifer Zeynab Joukhadar Maccani, Devin C. Koestler, Barry Lester, E Andres Houseman, David A. Armstrong, Karl T. Kelsey, Carmen J. Marsit

Dartmouth Scholarship

Background:

Prenatal mercury (Hg) exposure is associated with adverse child neurobehavioral outcomes. Because Hg can interfere with placental functioning and cross the placenta to target the fetal brain, prenatal Hg exposure can inhibit fetal growth and development directly and indirectly.

Objectives:

We examined potential associations between prenatal Hg exposure assessed through infant toenail Hg, placental DNA methylation changes, and newborn neurobehavioral outcomes.

Methods:

The methylation status of > 485,000 CpG loci was interrogated in 192 placental samples using Illumina’s Infinium HumanMethylation450 BeadArray. Hg concentrations were analyzed in toenail clippings from a subset of 41 infants; neurobehavior was assessed using the NICU …

Willingness To Test For Brca1/2 In High Risk Women: Influenced By Risk Perception And Family Experience, Rather Than By Objective Or Subjective Numeracy?, Talya Miron-Shatz, Yaniv Hanoch, Benjamin A. Katz, Glen M. Doniger, Elissa M. Ozanne

Dartmouth Scholarship

Genetic testing for breast and ovarian cancer can help target prevention programs, and possibly reduce morbidity and mortality. A positive result of BRCA1/2 is a substantial risk factor for breast and ovarian cancer, and its detection often leads to risk reduction interventions such as increased screening, prophylactic mastectomy and oophorectomy. We examined predictors of the decision to undergo cancer related genetic testing: perceived risk, family risk of breast or ovarian cancer, and numeracy as predictors of the decision to test among women at high risk of breast cancer. Stepwise regression analysis of survey responses from 459 women registered in the …

Obesity Early In Adulthood Increases Risk But Does Not Affect Outcomes Of Hepatocellular Carcinoma, Manal M. Hassan, Reham Abdel-Wahab, Ahmed Kaseb, Ahmed Shalaby, Alexandria Phan, Hashem El-Serag, Ernest Hawk, Jeff Morris, Kanwal Pratap Singh Raghav, Ju-Seog Lee, Jean-Nicolas Vauthey, Gehan Bortus, Harrys Torres, Christopher Amos, Robert Wolff, Donghui Li

Dartmouth Scholarship

Despite the significant association between obesity and several cancers, it has been difficult to establish an association between obesity and hepatocellular carcinoma (HCC). Patients with HCC often have ascites, making it a challenge to accurately determine body mass index (BMI), and many factors contribute to the development of HCC. We performed a case–control study to investigate whether obesity early in adulthood affects risk, age of onset, or outcomes of patients with HCC.

Patients Recording Clinical Encounters: A Path To Empowerment? Assessment By Mixed Methods, Glyn Elwyn, Paul James Barr, Stuart W. Grande

Dartmouth Scholarship

Objective: To examine the motivations of patients recording clinical encounters, covertly or otherwise, and why some do not wish to record encounters. Design: Mixed-methods analysis of survey data and nested semistructured interviews. Setting: Survey to UK audience, using social media and radio broadcast. Participants: 168 survey respondents, of whom 161 were 18 years of age or older (130 completions). Of the 56 participants who agreed to be contacted, we included data from 17 interviews.

A Structural And Functional Comparison Between Infectious And Non-Infectious Autocatalytic Recombinant Prp Conformers, Geoffrey P. Noble, Daphne W. Wang, Daniel J. Walsh, Justin R. Barone, Michael B. Miller, Koren A. Nishina, Sheng Li, Surachai Supattapone

Dartmouth Scholarship

Infectious prions contain a self-propagating, misfolded conformer of the prion protein termed PrPSc. A critical prediction of the protein-only hypothesis is that autocatalytic PrPSc molecules should be infectious. However, some autocatalytic recombinant PrPSc molecules have low or undetectable levels of specific infectivity in bioassays, and the essential determinants of recombinant prion infectivity remain obscure. To identify structural and functional features specifically associated with infectivity, we compared the properties of two autocatalytic recombinant PrP conformers derived from the same original template, which differ by >105-fold in specific infectivity for wild-type mice. Structurally, hydrogen/deuterium exchange mass spectrometry (DXMS) studies revealed that solvent …

Tooth Retrospective Dosimetry Using Electron Paramagnetic Resonance: Influence Of Irradiated Dental Composites, Céline M. Desmet, Andrej Djurkin, Ana Maria Dos Santos-Goncalvez, Ruhong Dong, Maciej M. Kmiec, Kyo Kobayashi, Kevin Rychert, Sébastien Beun, Julian G. Leprince, Gaëtane Leloup, Philippe Levêque, Bernard Gallez

Dartmouth Scholarship

In the aftermath of a major radiological accident, the medical management of overexposed individuals will rely on the determination of the dose of ionizing radiations absorbed by the victims. Because people in the general population do not possess conventional dosimeters, after the fact dose reconstruction methods are needed. Free radicals are induced by radiations in the tooth enamel of victims, in direct proportion to dose, and can be quantified using Electron Paramagnetic Resonance (EPR) spectrometry, a technique that was demonstrated to be very appropriate for mass triage. The presence of dimethacrylate based restorations on teeth can interfere with the dosimetric …

Enhancing Interferon Regulatory Factor 7 Mediated Antiviral Responses And Decreasing Nuclear Factor Kappa B Expression Limit Hiv-1 Replication In Cervical Tissues, Christiane Rollenhage, Sherrill L. Macura, Melissa J. Lathrop, Todd A. Mackenzie, Gustavo F. Doncel, Susana N. Asin

Dartmouth Scholarship

Establishment of a productive HIV-1 infection in the female reproductive tract likely depends on the balance between anti-viral and pro-inflammatory responses leading to activation and proliferation of HIV target cells. Immune modulators that boost anti-viral and depress pro-inflammatory immune responses may decrease HIV-1 infection or replication. Polyinosinic: polycytidylic [Poly (I:C)] has been reported to down-regulate HIV-1 replication in immune cell subsets and lymphoid tissues, yet the scope and mechanisms of poly (I:C) regulation of HIV-1 replication in the cervicovaginal mucosa, the main portal of viral entry in women remain unknown. Using a relevant, underexplored ex vivo cervical tissue model, we …

A Cysteine Zipper Stabilizes A Pre-Fusion F Glycoprotein Vaccine For Respiratory Syncytial Virus, Guillaume B. E. Stewart-Jones, Paul V. Thomas, Man Chen, Aliaksandr Druz, Gordon M. Joyce, Wing-Pui Kong, Mallika Sastry, Conque Soto, Yongping Yang, Baoshan Zhang, Lei Chen, Gwo-Yu Chuang, Ivelin S. Georgiev, Jason S. Mclellan

Dartmouth Scholarship

Recombinant subunit vaccines should contain minimal non-pathogen motifs to reduce potential off-target reactivity. We recently developed a vaccine antigen against respiratory syncytial virus (RSV), which comprised the fusion (F) glycoprotein stabilized in its pre-fusion trimeric conformation by “DS-Cav1” mutations and by an appended C-terminal trimerization motif or “foldon” from T4-bacteriophage fibritin. Here we investigate the creation of a cyste- ine zipper to allow for the removal of the phage foldon, while maintaining the immunogenic- ity of the parent DS-Cav1+foldon antigen. Constructs without foldon yielded RSV F monomers, and enzymatic removal of the phage foldon from pre-fusion F trimers resulted in …

Fresolimumab Treatment Decreases Biomarkers And Improves Clinical Symptoms In Systemic Sclerosis Patients, Lisa M. Rice, Cristina M. Padilla, Sarah R. Mclaughlin, Allison Mathes, Jessica Ziemek, Salma Goummih, Sashidhar Nakerakanti, Michael York, Giuseppina Farina, Michael L. Whitfield, Robert F. Spiera, Romy B. Christmann, Jessica K. Gordon, Janice Weinberg, Robert Lafyatis

Dartmouth Scholarship

BACKGROUND. TGF-β has potent profibrotic activity in vitro and has long been implicated in systemic sclerosis (SSc), as expression of TGF-β–regulated genes is increased in the skin and lungs of patients with SSc. Therefore, inhibition of TGF-β may benefit these patients.

METHODS. Patients with early, diffuse cutaneous SSc were enrolled in an open-label trial of fresolimumab, a high-affinity neutralizing antibody that targets all 3 TGF-β isoforms. Seven patients received two 1 mg/kg doses of fresolimumab, and eight patients received one 5 mg/kg dose of fresolimumab. Serial mid-forearm skin biopsies, performed before and after treatment, were analyzed for expression …

Structure-Based Redesign Of Lysostaphin Yields Potent Antistaphylococcal Enzymes That Evade Immune Cell Surveillance, Kristina Blazanovic, Hongliang Zhao, Yoonjoo Choi, Wen Li, Regina S. Salvat, Daniel C. Osipovitch, Jennifer Fields, Leonard Moise, Brent L. Berwin, Steven N. Fiering, Chris Bailey-Kellogg, Karl E. Griswold

Dartmouth Scholarship

Staphylococcus aureus infections exert a tremendous burden on the health-care system, and the threat of drug-resistant strains continues to grow. The bacteriolytic enzyme lysostaphin is a potent antistaphylococcal agent with proven efficacy against both drug-sensitive and drug-resistant strains; however, the enzyme's own bacterial origins cause undesirable immunogenicity and pose a barrier to clinical translation. Here, we deimmunized lysostaphin using a computationally guided process that optimizes sets of mutations to delete immunogenic T cell epitopes without disrupting protein function. In vitro analyses showed the methods to be both efficient and effective, producing seven different deimmunized designs exhibiting high function and …

Testing Multiple Hypotheses Through Imp Weighted Fdr Based On A Genetic Functional Network With Application To A New Zebrafish Transcriptome Study, Jiang Gui, Casey S. Greene, Con Sullivan, Walter Taylor, Jason H. Moore, Carol Kim

Dartmouth Scholarship

In genome-wide studies, hundreds of thousands of hypothesis tests are performed simultaneously. Bonferroni correction and False Discovery Rate (FDR) can effectively control type I error but often yield a high false negative rate. We aim to develop a more powerful method to detect differentially expressed genes. We present a Weighted False Discovery Rate (WFDR) method that incorporate biological knowledge from genetic networks. We first identify weights using Integrative Multi-species Prediction (IMP) and then apply the weights in WFDR to identify differentially expressed genes through an IMP-WFDR algorithm. We performed a gene expression experiment to identify zebrafish genes that change expression …

Maximizing The Impact Of Training Initiatives For Health Professionals In Low-Income Countries: Frameworks, Challenges, And Best Practices, Corrado Cancedda, Paul E. Farmer, Vanessa Kerry, Tej Nuthulaganti, Kirstin W. Scott, Eric Goosby, Agnes Binagwaho

Dartmouth Scholarship

Corrado Cancedda and colleagues outline a framework for health professional training initiatives in low-income countries.

Links Between Anr And Quorum Sensing In Pseudomonas Aeruginosa Biofilms, John H. Hammond, Emily F. Dolben, T. Jarrod Smith, Sabin Bhuju, Deborah Hogan

Dartmouth Scholarship

In Pseudomonas aeruginosa, the transcription factor Anr controls the cellular response to low oxygen or anoxia. Anr activity is high in oxygen-limited environments, including biofilms and populations associated with chronic infections, and Anr is necessary for persistence in a model of pulmonary infection. In this study, we characterized the Anr regulon in biofilm-grown cells at 1% oxygen in the laboratory strain PAO1 and in a quorum sensing (QS)-deficient clinical isolate, J215. As expected, transcripts related to denitrification, arginine fermentation, high-affinity cytochrome oxidases, and CupA fimbriae were lower in the Δanr derivatives. In addition, we observed that transcripts associated with quorum …

Whole Genome Capture Of Vector-Borne Pathogens From Mixed Dna Samples: A Case Study Of Borrelia Burgdorferi, Giovanna Carpi, Katharine S. Walter, Stephen J. Bent, Anne Gatewood Hoen, Maria Diuk-Wasser, Adalgisa Caccone

Dartmouth Scholarship

Background:

Rapid and accurate retrieval of whole genome sequences of human pathogens from disease vectors or animal reservoirs will enable fine-resolution studies of pathogen epidemiological and evolutionary dynamics. However, next generation sequencing technologies have not yet been fully harnessed for the study of vector-borne and zoonotic pathogens, due to the difficulty of obtaining high-quality pathogen sequence data directly from field specimens with a high ratio of host to pathogen DNA.

Results:

We addressed this challenge by using custom probes for multiplexed hybrid capture to enrich for and sequence 30 Borrelia burgdorferi genomes from field samples of its arthropod vector. Hybrid …

Iarc Monographs: 40 Years Of Evaluating Carcinogenic Hazards To Humans, Neil E. Pearce, Aaron Blair, Paolo Vineis, Wolfgang Ahrens, Aage Andersom, Josep M. Anto, Bruce K. Armstrong, Andrea A. Baccarelli, Frederick A. Beland, Amy Berrington, Pier Alberto Bertazzi, Linda S. Birnbaum, Ross C. Brownson, John R. Bucher, Kenneth P. Cantor, Elisabeth Cardis, John W. Cherrie, David C. Christiani, Pierluigi Cocco, David Coggon, Pietro Comba, Paul A. Demers, John M. Dement, Jeroen Douwes, Ellen A. Eisen, Lawrence S. Engel, Richard A. Fenske, Lora E. Fleming, Tony Fletcher, Elizabeth Fontham, Francesco Forastiere, Rainer Frentzel-Beyme, Lin Fritschi, Michel Gerin, Marcel Goldberg, Philippe Grandjean, Tom K. Grimsrud, Per Gustavsson, Andy Haines, Patricia Hartge, Johnni Hansen, Michael Hauptmann, Dick Heederik, Kari Hemminki, Denis Hemon, Irva Hertz-Picciotto, Jane A. Hoppin, James Huff, Bengt Jarvholm, Daehee Kang, Margaret R. Karagas

Dartmouth Scholarship

Background: Recently, the International Agency for Research on Cancer (IARC) Programme for the Evaluation of Carcinogenic Risks to Humans has been criticized for several of its evaluations, and also for the approach used to perform these evaluations. Some critics have claimed that failures of IARC Working Groups to recognize study weaknesses and biases of Working Group members have led to inappropriate classification of a number of agents as carcinogenic to humans.

Objectives: The authors of this Commentary are scientists from various disciplines relevant to the identification and hazard evaluation of human carcinogens. We examined criticisms of the IARC classification process …