CHAGAS DISEASE A M EDICAL D ICTIONARY , B IBLIOGRAPHY , AND A NNOTATED R ESEARCH G UIDE TO I NTERNET R E FERENCES
J AMES N. P ARKER , M.D. AND P HILIP M. P ARKER , P H .D., E DITORS
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ICON Health Publications ICON Group International, Inc. 4370 La Jolla Village Drive, 4th Floor San Diego, CA 92122 USA Copyright 2004 by ICON Group International, Inc. Copyright 2004 by ICON Group International, Inc. All rights reserved. This book is protected by copyright. No part of it may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without written permission from the publisher. Printed in the United States of America. Last digit indicates print number: 10 9 8 7 6 4 5 3 2 1
Publisher, Health Care: Philip Parker, Ph.D. Editor(s): James Parker, M.D., Philip Parker, Ph.D. Publisher's note: The ideas, procedures, and suggestions contained in this book are not intended for the diagnosis or treatment of a health problem. As new medical or scientific information becomes available from academic and clinical research, recommended treatments and drug therapies may undergo changes. The authors, editors, and publisher have attempted to make the information in this book up to date and accurate in accord with accepted standards at the time of publication. The authors, editors, and publisher are not responsible for errors or omissions or for consequences from application of the book, and make no warranty, expressed or implied, in regard to the contents of this book. Any practice described in this book should be applied by the reader in accordance with professional standards of care used in regard to the unique circumstances that may apply in each situation. The reader is advised to always check product information (package inserts) for changes and new information regarding dosage and contraindications before prescribing any drug or pharmacological product. Caution is especially urged when using new or infrequently ordered drugs, herbal remedies, vitamins and supplements, alternative therapies, complementary therapies and medicines, and integrative medical treatments. Cataloging-in-Publication Data Parker, James N., 1961Parker, Philip M., 1960Chagas Disease: A Medical Dictionary, Bibliography, and Annotated Research Guide to Internet References / James N. Parker and Philip M. Parker, editors p. cm. Includes bibliographical references, glossary, and index. ISBN: 0-497-00219-1 1. Chagas Disease-Popular works. I. Title.
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Disclaimer This publication is not intended to be used for the diagnosis or treatment of a health problem. It is sold with the understanding that the publisher, editors, and authors are not engaging in the rendering of medical, psychological, financial, legal, or other professional services. References to any entity, product, service, or source of information that may be contained in this publication should not be considered an endorsement, either direct or implied, by the publisher, editors, or authors. ICON Group International, Inc., the editors, and the authors are not responsible for the content of any Web pages or publications referenced in this publication.
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Acknowledgements The collective knowledge generated from academic and applied research summarized in various references has been critical in the creation of this book which is best viewed as a comprehensive compilation and collection of information prepared by various official agencies which produce publications on Chagas disease. Books in this series draw from various agencies and institutions associated with the United States Department of Health and Human Services, and in particular, the Office of the Secretary of Health and Human Services (OS), the Administration for Children and Families (ACF), the Administration on Aging (AOA), the Agency for Healthcare Research and Quality (AHRQ), the Agency for Toxic Substances and Disease Registry (ATSDR), the Centers for Disease Control and Prevention (CDC), the Food and Drug Administration (FDA), the Healthcare Financing Administration (HCFA), the Health Resources and Services Administration (HRSA), the Indian Health Service (IHS), the institutions of the National Institutes of Health (NIH), the Program Support Center (PSC), and the Substance Abuse and Mental Health Services Administration (SAMHSA). In addition to these sources, information gathered from the National Library of Medicine, the United States Patent Office, the European Union, and their related organizations has been invaluable in the creation of this book. Some of the work represented was financially supported by the Research and Development Committee at INSEAD. This support is gratefully acknowledged. Finally, special thanks are owed to Tiffany Freeman for her excellent editorial support.
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About the Editors James N. Parker, M.D. Dr. James N. Parker received his Bachelor of Science degree in Psychobiology from the University of California, Riverside and his M.D. from the University of California, San Diego. In addition to authoring numerous research publications, he has lectured at various academic institutions. Dr. Parker is the medical editor for health books by ICON Health Publications. Philip M. Parker, Ph.D. Philip M. Parker is the Eli Lilly Chair Professor of Innovation, Business and Society at INSEAD (Fontainebleau, France and Singapore). Dr. Parker has also been Professor at the University of California, San Diego and has taught courses at Harvard University, the Hong Kong University of Science and Technology, the Massachusetts Institute of Technology, Stanford University, and UCLA. Dr. Parker is the associate editor for ICON Health Publications.
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About ICON Health Publications To discover more about ICON Health Publications, simply check with your preferred online booksellers, including Barnes&Noble.com and Amazon.com which currently carry all of our titles. Or, feel free to contact us directly for bulk purchases or institutional discounts: ICON Group International, Inc. 4370 La Jolla Village Drive, Fourth Floor San Diego, CA 92122 USA Fax: 858-546-4341 Web site: www.icongrouponline.com/health
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Table of Contents FORWARD .......................................................................................................................................... 1 CHAPTER 1. STUDIES ON CHAGAS DISEASE ..................................................................................... 3 Overview........................................................................................................................................ 3 The Combined Health Information Database................................................................................. 3 Federally Funded Research on Chagas Disease.............................................................................. 4 E-Journals: PubMed Central ....................................................................................................... 17 The National Library of Medicine: PubMed ................................................................................ 18 CHAPTER 2. NUTRITION AND CHAGAS DISEASE............................................................................ 55 Overview...................................................................................................................................... 55 Finding Nutrition Studies on Chagas Disease ............................................................................ 55 Federal Resources on Nutrition ................................................................................................... 56 Additional Web Resources ........................................................................................................... 57 CHAPTER 3. ALTERNATIVE MEDICINE AND CHAGAS DISEASE ..................................................... 59 Overview...................................................................................................................................... 59 National Center for Complementary and Alternative Medicine.................................................. 59 Additional Web Resources ........................................................................................................... 65 General References ....................................................................................................................... 66 CHAPTER 4. DISSERTATIONS ON CHAGAS DISEASE ....................................................................... 67 Overview...................................................................................................................................... 67 Dissertations on Chagas Disease ................................................................................................. 67 Keeping Current .......................................................................................................................... 67 CHAPTER 5. BOOKS ON CHAGAS DISEASE ...................................................................................... 69 Overview...................................................................................................................................... 69 Book Summaries: Federal Agencies.............................................................................................. 69 CHAPTER 6. PERIODICALS AND NEWS ON CHAGAS DISEASE ........................................................ 71 Overview...................................................................................................................................... 71 News Services and Press Releases................................................................................................ 71 Academic Periodicals covering Chagas Disease ........................................................................... 73 APPENDIX A. PHYSICIAN RESOURCES ............................................................................................ 77 Overview...................................................................................................................................... 77 NIH Guidelines............................................................................................................................ 77 NIH Databases............................................................................................................................. 79 Other Commercial Databases....................................................................................................... 81 APPENDIX B. PATIENT RESOURCES ................................................................................................. 83 Overview...................................................................................................................................... 83 Patient Guideline Sources............................................................................................................ 83 Finding Associations.................................................................................................................... 85 APPENDIX C. FINDING MEDICAL LIBRARIES .................................................................................. 87 Overview...................................................................................................................................... 87 Preparation................................................................................................................................... 87 Finding a Local Medical Library.................................................................................................. 87 Medical Libraries in the U.S. and Canada ................................................................................... 87 ONLINE GLOSSARIES.................................................................................................................. 93 Online Dictionary Directories ..................................................................................................... 95 CHAGAS DISEASE DICTIONARY............................................................................................. 97 INDEX .............................................................................................................................................. 131
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FORWARD In March 2001, the National Institutes of Health issued the following warning: "The number of Web sites offering health-related resources grows every day. Many sites provide valuable information, while others may have information that is unreliable or misleading."1 Furthermore, because of the rapid increase in Internet-based information, many hours can be wasted searching, selecting, and printing. Since only the smallest fraction of information dealing with Chagas disease is indexed in search engines, such as www.google.com or others, a non-systematic approach to Internet research can be not only time consuming, but also incomplete. This book was created for medical professionals, students, and members of the general public who want to know as much as possible about Chagas disease, using the most advanced research tools available and spending the least amount of time doing so. In addition to offering a structured and comprehensive bibliography, the pages that follow will tell you where and how to find reliable information covering virtually all topics related to Chagas disease, from the essentials to the most advanced areas of research. Public, academic, government, and peer-reviewed research studies are emphasized. Various abstracts are reproduced to give you some of the latest official information available to date on Chagas disease. Abundant guidance is given on how to obtain free-of-charge primary research results via the Internet. While this book focuses on the field of medicine, when some sources provide access to non-medical information relating to Chagas disease, these are noted in the text. E-book and electronic versions of this book are fully interactive with each of the Internet sites mentioned (clicking on a hyperlink automatically opens your browser to the site indicated). If you are using the hard copy version of this book, you can access a cited Web site by typing the provided Web address directly into your Internet browser. You may find it useful to refer to synonyms or related terms when accessing these Internet databases. NOTE: At the time of publication, the Web addresses were functional. However, some links may fail due to URL address changes, which is a common occurrence on the Internet. For readers unfamiliar with the Internet, detailed instructions are offered on how to access electronic resources. For readers unfamiliar with medical terminology, a comprehensive glossary is provided. For readers without access to Internet resources, a directory of medical libraries, that have or can locate references cited here, is given. We hope these resources will prove useful to the widest possible audience seeking information on Chagas disease. The Editors
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From the NIH, National Cancer Institute (NCI): http://www.cancer.gov/cancerinfo/ten-things-to-know.
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CHAPTER 1. STUDIES ON CHAGAS DISEASE Overview In this chapter, we will show you how to locate peer-reviewed references and studies on Chagas disease.
The Combined Health Information Database The Combined Health Information Database summarizes studies across numerous federal agencies. To limit your investigation to research studies and Chagas disease, you will need to use the advanced search options. First, go to http://chid.nih.gov/index.html. From there, select the “Detailed Search” option (or go directly to that page with the following hyperlink: http://chid.nih.gov/detail/detail.html). The trick in extracting studies is found in the drop boxes at the bottom of the search page where “You may refine your search by.” Select the dates and language you prefer, and the format option “Journal Article.” At the top of the search form, select the number of records you would like to see (we recommend 100) and check the box to display “whole records.” We recommend that you type “Chagas disease” (or synonyms) into the “For these words:” box. Consider using the option “anywhere in record” to make your search as broad as possible. If you want to limit the search to only a particular field, such as the title of the journal, then select this option in the “Search in these fields” drop box. The following is what you can expect from this type of search: •
American Trypanosomiasis (Chagas' Disease) Source: Gastroenterology Clinics of North America. 25(3): 517-533. September 1996. Contact: Available from W.B. Saunders Company, Periodicals Fulfillment, 6277 Sea Harbor Drive, Orlando, FL 32887. (800) 654-2452. Summary: This article reviews American trypanosomiasis or Chagas' disease, an illness caused by the protozoan parasite Trypanosoma cruzi. Gastrointestinal (GI) dysfunction is a major problem for many patients with chronic Chagas' disease; the underlying anatomic abnormality in these patients is a denervation of the GI tract. This process of nerve destruction usually develops insidiously over many years, and it is highly variable. Megaesophagus is the most common manifestation of GI Chagas' disease, and mechanical dilation of the esophageal sphincter or surgery in advanced cases usually
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give satisfactory relief of symptoms. Megacolon, particularly of the sigmoid segment, is also common in patients with chronic T. cruzi infections, and its presence can be complicated by fecal impaction or sigmoid volvulus. Patients with advanced megacolon who have resections of the sigmoid colon and most of the rectum generally do well postoperatively. 4 figures. 90 references. (AA-M).
Federally Funded Research on Chagas Disease The U.S. Government supports a variety of research studies relating to Chagas disease. These studies are tracked by the Office of Extramural Research at the National Institutes of Health.2 CRISP (Computerized Retrieval of Information on Scientific Projects) is a searchable database of federally funded biomedical research projects conducted at universities, hospitals, and other institutions. Search the CRISP Web site at http://crisp.cit.nih.gov/crisp/crisp_query.generate_screen. You will have the option to perform targeted searches by various criteria, including geography, date, and topics related to Chagas disease. For most of the studies, the agencies reporting into CRISP provide summaries or abstracts. As opposed to clinical trial research using patients, many federally funded studies use animals or simulated models to explore Chagas disease. The following is typical of the type of information found when searching the CRISP database for Chagas disease: •
Project Title: A GENETIC SYSTEM FOR KINETOPLASTID DRUG DISCOVERY Principal Investigator & Institution: Swindle, John T.; Vice President and Chief Scientific Offi; Complegen, Inc. 1124 Columbia St, Ste 662 Seattle, Wa 981042050 Timing: Fiscal Year 2003; Project Start 01-MAY-2003; Project End 30-APR-2004 Summary: (provided by applicant): The goal of this project is to apply a novel, well developed cost effective means of drug target and drug discovery to parasitic disease, focusing on Trypanosoma cruzi and Leishmania, the causative agents of Chagas disease and Leishmanaisis respectively. This project will generate comparative compound screens to identify new anti-kinetoplastid compounds that are broadly applicable to both T. cruzi and Leishmania species. The identification of broad-spectrum therapeutics will facilitate later commercialization by significantly increasing the potential market for new therapeutics, an important attribute since most of the afflicted populations are poor. The experimental approach exploits a novel method for identifying compounds that interact specifically with trypanosomal protein targets but not with the human analogs. In this method, T. cruzi, Leishmania sp., and human genes are introduced into yeast, functionally replacing the cognate yeast genes. A collection of these yeast strains, each bearing a different trypanosomatid or human gene (trypanosomatid and human XenoGene arrays), can be used as compound screening platforms in a high through-put bioassay to identify compounds which specifically inhibit the function of the trypanosome targets but not analogous targets in the human XenoGene array. This application also includes a pilot small molecule screen of selected kinetoplastid targets. Website: http://crisp.cit.nih.gov/crisp/Crisp_Query.Generate_Screen
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Healthcare projects are funded by the National Institutes of Health (NIH), Substance Abuse and Mental Health Services (SAMHSA), Health Resources and Services Administration (HRSA), Food and Drug Administration (FDA), Centers for Disease Control and Prevention (CDCP), Agency for Healthcare Research and Quality (AHRQ), and Office of Assistant Secretary of Health (OASH).
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Project Title: A STRATEGY FOR SPREADING GENES IN CHAGAS DISEASE VECTORS Principal Investigator & Institution: Durvasula, Ravi V.; Epidemiology and Public Health; Yale University 47 College Street, Suite 203 New Haven, Ct 065208047 Timing: Fiscal Year 2002; Project Start 01-APR-2001; Project End 31-MAR-2005 Summary: A paratransgenic strategy aimed at decreasing transmission of trypanasoma cruzi, the causative agent of Chagas disease, from reduviid vectors to man is being developed. The symbiotic bacterium, Rhodococcus rhodnii, that resides in the reduviid vector, Rhodnius prolixus, has been transformed to export peptides toxic to T. cruzi and single chain antibodies that may be engineered to target T. cruzi. In this proposal, a strategy to spread engineered symbiotic bacteria in field populations of the vector will be studied. The synthetic fecal paste, CRUZIGARD, that has been formulated to mimic naturally occurring coprophagic methods of symbiont transfer in Rhodnius prolixus will be evaluated as a gene spreading strategy. In Aim I 'the fitness of engineered symbiotic bacteria to compete with wild-type organisms to establish infection in the host vector will be assessed. In co-infection studies of aposymbiotic R. prolixus (bugs that are specially reared to be free of gut-associated bacteria), effects of different gene constructs on fitness will be determined. In Aim 2, the potential non-target gene spread will be evaluated. In closed cage-studies uptake and retention of transgenes by arthropods that do not transmit T. cruzi (ants, crickets, fleas and cockroaches) but-may be exposed to CRUZIGARD will be determined. Furthermore, transfer of genetic material from engineered bacteria to other environmental microbes will be characterized. Aim 3 will involve simulated release of transgeuic microbes in life-size huts that are contained within a greenhouse facility. Huts will be constructed of standard materials and infested with reduviid bugs. Various applications of CRUZIGARD will be used to determine extent of gene spread in a hut and possible hut-to-hut transfer of genetic materials. From these studies, optimal methods for gene delivery via CRUZIGARD can be established. Website: http://crisp.cit.nih.gov/crisp/Crisp_Query.Generate_Screen
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Project Title: ADAPTATION OF RIBOZYME TECHNOLOGY TO LEISHMANIA Principal Investigator & Institution: Sturm, Nancy R.; Microbiology and Immunology; University of California Los Angeles 10920 Wilshire Blvd., Suite 1200 Los Angeles, Ca 90024 Timing: Fiscal Year 2003; Project Start 01-APR-2003; Project End 31-MAR-2005 Summary: (provided by the applicant): Directed ribozyme activity will add a valuable tool to the arsenal of techniques for study of small RNAs, and has not yet been reported in the kinetoplastids. This research is aimed at understanding gene expression in the family Trypanosomatidae, which includes the parasitic protozoan responsible for leishmaniasis, African sleeping sickness, and Chagas Disease. The focus is on the genesis and function of the spliced leader RNA, a small RNA which contributes the 5'end sequence to every nuclear messenger RNA via a trans-splicing reaction. Transsplicing is not found in the human host or insect vector, and thus represents a possible therapeutic target. This proposal outlines two series of experiments aimed at exploring the use of hammerhead ribozymes while elucidating the maturation pathway of the spliced leader RNA in Leishmania tarentolae: 1) Ribozyme activity in cis (monomolecular) will be used to specify the 3' end of the spliced leader RNA. Stable products will allow us to overcome known processing defects for specific mutations in the spliced leader RNA and to examine downstream processing events including 5' methylation and trans-splicing. 2) Ribozymes will be used in trans (hi-molecular) to assay for
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nucleolar trafficking by attaching the ribozyme to a nucleolar U3 snoRNA. The nucleolar ribozyme will be directed against the spliced leader RNA and the spliced leader associated 1 RNA. Efficient ablation of RNA targets has great potential for elucidating the role of conserved sequences, structures and subcellular Iocalization. Once the parameters of the technique are established increasingly ambitious experiments can be designed including targeting of the spliced SL or discrete mRNAs. Website: http://crisp.cit.nih.gov/crisp/Crisp_Query.Generate_Screen •
Project Title: ANTI-TRYPANOSOMAL AGENTS FROM A NEOTROPICAL CLOUDFOREST Principal Investigator & Institution: Setzer, William N.; Professor; Chemistry; University of Alabama in Huntsville Office of Sponsored Programs Huntsville, Al 35899 Timing: Fiscal Year 2004; Project Start 01-MAY-2004; Project End 30-APR-2007 Summary: (provided by applicant): Over 18 million people in tropical and subtropical America are afflicted by American trypanosomiasis or Chagas disease. The disease is caused by the parasitic protozoan Trypanosoma cruzi, which is transmitted by Triatomid ("kissing") bugs. The parasite enters the body through the eyes, mucous membranes, or open wounds. After entering the body, the parasite burrows into cells and begins to multiply, causing rupture of the parasitized cell, and newly produced parasites are then released into the blood. In humans, symptoms of the disease include fever, swelling, and heart and brain damage, usually leading to death. There is currently no effective treatment for this disease. The purpose of this research program is to find new medicines from tropical cloudforest plants for treatment of this parasitic disease. Tropical cloudforests are incredibly diverse, and tropical plants have evolved chemical defenses to protect themselves from being consumed by insects, nematodes, fungus attack, etc. These multitudinous chemicals, developed over millions of years, have varied and diverse structures and interfere with many different biochemical targets. Our hypothesis is that tropical cloudforest plants represent a storehouse of new chemical agents that may also inhibit parasites such as Trypanosoma. These compounds may be promising drug candidates themselves, or they may serve as templates for further synthetic elaboration and optimization. Our plan of attack in this proposal is: (a) to screen our collection of tropical rainforest plant extracts for killing of the parasites in culture, (b) to test our extracts for inhibition of some key enzymes necessary for survival of the protozoa, (c) when we find active extracts, to isolate and determine the structures of the active compounds, (d) to see how active compounds bind to enzyme target molecules, and (e) to determine the effectiveness of new potential drugs a mouse model. The long-term benefit of this research project is the development of new medicines to treat patients with Chagas disease. Website: http://crisp.cit.nih.gov/crisp/Crisp_Query.Generate_Screen
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Project Title: ASSESSMENT OF STROKE RISK AND OUTCOME IN CHAGAS DISEASE Principal Investigator & Institution: Furie, Karen L.; Assistant Professor; Massachusetts General Hospital 55 Fruit St Boston, Ma 02114 Timing: Fiscal Year 2003; Project Start 30-SEP-2003; Project End 30-JUN-2005 Summary: (provided by applicant): Stroke is an enormous international public health concern, particularly in the developing world where there are limited resources available to provide for an aging population. One of the main contributors to stroke incidence in Brazil is the highly prevalent Chagas disease, a parasitic infection affecting
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14% of the population and a major cause of heart failure in Latin America. Chagas disease conveys stroke risk through two established mechanisms, structural cardiac disease and chronic inflammation. Although inflammation is associated with an increased risk of ischemic stroke and poorer outcome, its role has been largely linked to atherogenesis. Chronic inflammation can result in endothelial dysfunction and stimulate the hemostatic system, increasing systemic fibrin production and platelet activation. Adults, young and old, who develop a secondary cardiomyopathy from Chagas, are therefore at higher risk of cardioembolism. Stroke patients usually survive, but can be left with significant disability affecting their health status, productivity, and quality of life. These factors impact caregivers as well. Thus, the social and economic consequences of stroke are vast. The short term goals of this planning grant are to develop a multidisciplinary collaborative infrastructure of investigators and resources in the United States and Brazil to promote clinical stroke research, to provide training for emerging Brazilian clinical stroke researchers, and to determine the resources necessary to support this clinical research effort in future endeavors. As part of this development phase, we will collect pilot data to address two specific aims: (1) to elucidate which of the potential inflammatory and hemostatic markers of stroke risk are associated with chagasic cardiomyopathy, and (2) to determine the mechanism and outcome of stroke in patients with Chagas disease. The long-term goal of this project is to establish noninvasive methods of stroke risk stratification and prediction of stroke outcome in patients with Chagas disease. This work will also facilitate the development of novel anti-trypanosomal, anti-inflammatory, and antithrombotic strategies for stroke prevention and management in Brazil. Website: http://crisp.cit.nih.gov/crisp/Crisp_Query.Generate_Screen •
Project Title: BABOON MODEL OF CHAGAS DISEASE: T CRUZI Principal Investigator & Institution: Vandeberg, John L.; Director; Southwest Foundation for Biomedical Res San Antonio, Tx 782450549 Timing: Fiscal Year 2002; Project Start 01-MAY-2002; Project End 30-APR-2003 Summary: The overall objectives of this pilot study are to determine the feasibility of developing a nonhuman primate model for research on the etiology of Chagas' disease, to contribute to understanding the clinical condition of nonhuman primates that are naturally infected with Trypanosoma cruzi (the causative agent of Chagas' disease), and to protect against the use of T cruzi infected baboons as organ donors for xenotransplantation. The project will involve surveying 2,600 baboons for seropositivity to determine age-specific, sex-specific, and housing-specific prevalences of T. cruzi infection. The project will determine ages of seroconversion. and the heritability of seropositivity. The chromosomal location of polymorphic genes that confer differential susceptibility to T. cruzi infection will be sought by linkage analysis using 330 microsatellite markers already typed in the pedigreed baboons. The pathology of seropositive animals will be carefully documented at necropsy. Results obtained from this pilot study are expected to justify its expansion into a major model development project. The validation of a naturally occurring nonhuman primate model of Chagas' disease will be a major accomplishment for future research purposes, will enable a better understanding of the clinical condition of animals at the Center, and will provide a means for preventing the inadvertent infection of humans with T. cruzi via xenotransplantation. Website: http://crisp.cit.nih.gov/crisp/Crisp_Query.Generate_Screen
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Project Title: COMPLEMENT REGULATION IN TRYPANOSOMA CRUZI Principal Investigator & Institution: Norris, Karen A.; Associate Professor; Molecular Genetics & Biochem; University of Pittsburgh at Pittsburgh 350 Thackeray Hall Pittsburgh, Pa 15260 Timing: Fiscal Year 2002; Project Start 01-MAR-1992; Project End 31-MAY-2006 Summary: (provided by the applicant): The goal of this research is the molecular and immunologic characterization of the 160 kDa complement regulatory protein (CRP) of the protozoan parasite, Trypanosoma cruzi, the causative agent of Chagas disease. After infection of the vertebrate host, the bloodstream stage trypomastigote is capable of evading host alternative and classical complement activation pathways, allowing dissemination to targettissues and intracellular replication. This is accomplished through the production of adevelopmentally regulated surface glycoprotein, CRP that restricts complement activation atthe level of C3 convertase formation. Our hypothesis is that immunologic neutralization of theCRP contributes to destruction of the extracellular bloodstream stage, and thus will contribute to protection from disease. We have shown that immunization with plasmid DNA encoding the full length CRP structural gene elicits neutralizing antibodies and protects against a lethal challenge in a murine model of Chagas disease. Three specific aims are designed to optimize the design of vaccine candidates based on the CRP gene and to characterize the immune responses to the protein, in vivo. Specific Aim 1 will provide a molecular analysis of the active domains of CRP and the binding interaction between CRP and its ligand, the complement component C3b. The functional analysis will be carried out using mutant CRP constructs expressed in mammalian cells and assayed for complement restriction activity and C3b binding. In addition, we will use neutralizing anti-CRP monoclonal antibodies and CRP-binding peptides to provide a finer map of activity. Specific Aim 2 will focus on an evaluation of CRP-DNA based vaccines in a murine model of Chagas disease. In these studies we will compare three expression vectors, optimize immunization protocols, and evaluate the range of protection using multiple mouse and parasite strains. In addition, we will examine oral and mucosal vaccine delivery systems and mucosal, sub-lethal challenge regimens. The goal of Specific Aim 3 is to analyze the immune effector mechanisms involved in the pmtective anti-CRP response. The role of immune antibodies will be evaluated in DNA immunized mice to determine if conformationally dependent epitopes are essential to the induction of a protective response. Passive transfer and challenge studies will be conducted and we will test vaccinated mice for the presence of CRP-specific cytotoxic T cells using CRP-expressing target cells. The successful completion of these aims will provide the first functional and immunological evaluation of a critical virulence factor of T. cruzi and provide information and reagents for the use of CRP as a vaccine candidate. Website: http://crisp.cit.nih.gov/crisp/Crisp_Query.Generate_Screen
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Project Title: DEVELOPMENT OF PARATRANSGENIC TICKS FOR DISEASE CONTROL Principal Investigator & Institution: Munderloh, Ulrike G.; Research Associate Professor; Entomology; University of Minnesota Twin Cities 200 Oak Street Se Minneapolis, Mn 554552070 Timing: Fiscal Year 2002; Project Start 01-JUL-2002; Project End 30-APR-2007 Summary: (provided by the applicant): Tick-borne diseases are increasingly diagnosed in humans and animals. Some are due to the resurgence of previously known illnesses, like Rocky Mountain spotted fever (Walker 1995). but others are due to new, emerging
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pathogens. Among the spotted fever group (SFG) alone, 8 new human pathogens have been described in the last 15 years (Stenos et al. 1997; Nilsson et al. 1999; Fournier et al. 2000), but they also include viruses, ehilichias and Babesia (Dawson et al. 1991; Thomford et al. 1994; Bakken et al. 1994; Telford et al 1991). Novel, efficient, specific and environmentally acceptable methods that interfere with disease transmission by ticks are urgently needed. Using paratransgenic ticks that carry symbiotic prokaryotes expressing an antimicrobial substance, as has been achieved with the symbiote of the Chagas disease vector, Rhodnius prolixus (Durvasula et aL 1997), could offer a safe and effective way to reduce disease transmission by ticks. A major obstacle to accomplishing this goal has been the lack of culture systems for tick symbiotes. Our laboratory has the largest collection of tick cell lines. We have successfully used these to isolate tickassociated rickettsiae (Munderloh et al. 1998; Weller et al. 1998; Palmer et al. 1999; Simser et al. 2001a,b) from the Lone Star tick (MOAa), the Rocky Mountain wood tick (R. peacockli DAE100R), and the Castor Bean tick (Rmoreli T2). We have characterized these microbes by light and electron microscopy, by using specific antibodies, as well as by PCR and nucleotide sequence analysis of 165 rDNA and other key genes. We are now in the process of defining the cultures to facilitate genetic manipulation of the symbiotes. Ourlong-termaim is the stabletransformation of Rickettsiapeacockii with cecropinA. an insect ponn gene (Hultmark et al. 1983). Infection of ticks with the transformed rickettsia, and interference with pathogen transmission. We plan to target the nonfunctional rompA gene of R. peacockli as a site for homologous transformation, avoiding deleterious effects associated with disruption of a vital gene, e.g. the rpoB gene (troyer et al. 1999). We will take the recent advances in successful transformation of insect-borne rickettsiae as a guide (Rachek et al. 1998; Troyer et al. 1999). and also apply transposome technology (Epicentre). Specifically, we will 1. optimize culture conditions for production of R. peacockii in tick cell culture, exanine its behavior in tick and mammalian cell culture by light and electron microscopy. 2. We will analyze cultured R. peacockii in ticks in terms of tissue tropism and transstadial/transovanal passage, and sensitivity to Cecropin A. Finally, we will work towards 3. stable transformation of R. peacockii with cecropinA. We will then test the transfonnants for antimicrobial activity in vitro and in ticks, and characterize them by sequence analysis. Website: http://crisp.cit.nih.gov/crisp/Crisp_Query.Generate_Screen •
Project Title: ECOEPIDEMIOLOGY OF CHAGAS DISEASE IN NORTHWEST ARGENTINA Principal Investigator & Institution: Kitron, Uriel D.; Professor; Animal Sciences and Veterinary Pathobiology; University of Illinois Urbana-Champaign Henry Administration Bldg Champaign, Il 61820 Timing: Fiscal Year 2002; Project Start 01-AUG-2002; Project End 31-MAY-2007 Summary: (provided by applicant): Chagas disease (American Trypanosomiasis), caused by Trypanosoma cruzi and transmitted by triatomine bugs, is the most important vector-borne disease in Latin America. Despite an ongoing eradication campaign, transmission persists in much of the continent, particularly in the Gran Chaco of northern Argentina, Paraguay and Bolivia, where Triatoma infestans is the main vector. Abundant peridomestic structures (particularly animal corrals) provide a refuge and source for repeated domestic reinfestation, dogs are a continuous source of infection for colonizing triatomine bugs, and sylvatic vectors invading human habitations may also play a role in reintroducing T. cruzi. The long-term goal of this project is to interrupt the reinfestation process and introduction of infection into homes. High degree of spatial, temporal and host heterogeneity with regard to vector and parasite survival,
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reproduction and spread, and ongoing anthropogenic changes have to be considered to understand infestation and infection patterns. Data derived from molecular tools, satellite imagery and field observations and experiments will be integrated into a GIS and mathematical models to elucidate the underlying biological mechanisms and epidemiological processes. The Specific Aims of the project are: 1) To analyze the spatial and temporal pattern of reinfestation by triatomine bugs and distribution of T. cruzi infection in bugs, dogs and people in three rural communities with the aid of satellite imagery, GIS, spatial statistics and other analytical tools; 2) To identify mechanisms underlying these patterns using field observations, field manipulations and experimental studies, and relate changes in these patterns to management strategies, habitat degradation and other anthropogenic changes; 3) To determine the source of colonizing vectors and T. cruzi infection by comparing the genetic makeup of bug and parasite strains using molecular techniques and morphometry; 4) To develop an empirically based, spatially structured mathematical model of the reinfestation and transmission process at the community-wide level; 5) On a coarser scale, to apply the results and develop risk maps of the distribution of household infestation by T. infestans and T. cruzi infection at the village, Department and Province-wide level; to compare effects of standard vs. scientifically designed intervention programs on infestation level and rate of reinfestation in new communities; and 6) To train scientists and NVCP personnel in the use of ecological and epidemiological tools, modeling, GIS and remote sensing techniques for research design and focused control strategies. Website: http://crisp.cit.nih.gov/crisp/Crisp_Query.Generate_Screen •
Project Title: EXPRESSION OF THE LEISHMANIA TARENTOLAE SL RNA GENE Principal Investigator & Institution: Campbell, David A.; Microbiology and Immunology; University of California Los Angeles 10920 Wilshire Blvd., Suite 1200 Los Angeles, Ca 90024 Timing: Fiscal Year 2002; Project Start 01-DEC-1994; Project End 29-FEB-2004 Summary: Leishmaniasis, African Sleeping Sickness and Chagas Disease are fatal or debilitating diseases that afflict over 20 million people annually in tropical countries and are caused by infections with related trypanosomatid protozoa. We are studying features of trypanosomatid gene expression that are shared among the pathogens, but which are absent in the human host. The expression of the parasite's Spliced Leader RNA gene and the role of its primary transcript, the SL RNA, in the maturation of nuclear messenger RNAs (mRNA) via trans-splicing is the focus of our research. We are taking molecular genetic and biochemical approaches to defining the promoter that directs initiation of SL RNA gene transcription, and characterizing protein(s) that bind to the SL RNA gene promoter. In the next funding period we propose to: 1) define the protein-DNA interactions in transcription initiation from the SL RNA gene promoter, and to identify the RNA polymerase that transcribes the SL RNA gene through a genetic approach, 2) define additional regions of the SL RNA gene that are necessary for transcription termination and efficient transcription initiation, and 3) analyze the effect of mutations in the Spliced Leader that may affect translation. These experiments will identify new molecules and elucidate essential protein-DNA and RNA-RNA interactions that distinguish the parasite's metabolism from that of the human host. These unique features represent potential targets for selective therapeutic intervention. Website: http://crisp.cit.nih.gov/crisp/Crisp_Query.Generate_Screen
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Project Title: FUNCTION OF THE KINETOPLAST IN THE HEMOFLAGELLATES Principal Investigator & Institution: Simpson, Larry P.; Professor; Molecular, Cellular & Dev Biol; University of California Los Angeles 10920 Wilshire Blvd., Suite 1200 Los Angeles, Ca 90024 Timing: Fiscal Year 2002; Project Start 01-MAY-1977; Project End 30-APR-2005 Summary: The long term goal of this project is to understand the molecular mechanism of the uridine-insertion/deletion type of RNA editing that occurs in the mitochondrion of kinetoplastid protozoa. The specific aims of this project are as follows: 1. Isolation of mitochondrial proteins and cloning of genes involved in RNA editing. Both enzymatic and structural proteins will be investigated. The genes will be cloned and expressed both in E. coli and as tagged proteins in L. tarentolae, and the recombinant proteins used to generate antibodies. Gene knockouts will be performed either by disruption of both alleles or by RNAi functional knockouts, and the effect on editing assayed both in vivo and in vitro. The recombinant proteins will be used to attempt to reconstitute editing activities in vitro. 2. Investigation of the mechanism of double strand RNA-induced (RNAi) inhibition of gene function. 3. Isolation of a functional 20S editing complex from Trypanosoma brucei procyclic cells; purification and identification of individual proteins and cloning genes. 4. Regulation of editing in T. brucei and Leishmania during life cycle, growth in culture, and during cell cycle. 5. Development of a transient mitochondrial expression system and a stable mitochondrial transformation system for use in studying RNA editing. 6. Investigation of the specific C34-U34 editing of the anticodon of imported tRNATrp in L. tarentolae. These parasites represent the causal agents of a variety of human animal and plant diseases, such as visceral and dermal leishmaniasis, Chagas Disease, African trypanosomiasis, and palm decay diseases. The existence of such a unique metabolic pathway as U-insertion/deletion RNA editing may provide a selective handle for chemotherapeutic intervention without affecting the host. Editing is required for the mt metabolism of these cells. A detailed knowledge of the enzymes involved in editing and the precise molecular pathways may allow the development of drugs which can kill the parasite and not affect the host. Website: http://crisp.cit.nih.gov/crisp/Crisp_Query.Generate_Screen
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Project Title: FUNCTIONAL GENOMICS OF METACYCLOGENESIS IN T.CRUZI Principal Investigator & Institution: Buck, Gregory A.; Professor & Director, Molecular Biol. &; Microbiology and Immunology; Virginia Commonwealth University Richmond, Va 232980568 Timing: Fiscal Year 2002; Project Start 01-JUL-2002; Project End 30-JUN-2007 Summary: (provided by applicant): Chagas disease, caused by Trypanosoma cruzi, is globally ranked behind malaria and schistosomiasis as the third most serious parasitic disease, and remains the most serious parasitic disease in Latin America in terms of disability adjusted life years. Despite recent progress controlling dissemination of T. cruzi in reduviid bugs, no treatment is available for chronic Chagas disease, and acute infections can only be treated with highly toxic drugs. Thus, there is a critical need for new approaches to treatment of T. cruzi infections. Metacyclogenesis is the process by which non-infectious "insect form" epimastigotes of T. cruzi differentiate into infectious metacyclic trypomastigotes. This process is the subject of much interest among scientists because of the implications for treatment/prevention of Chagas disease. We have used an axenic model system for metacyclogenesis, begun a nonredundant microarray of sequence-verified cDNA sequences, and established an exogenously regulated expression system that can be used to dissect this important differentiation system. The
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specific aims of the project are: 1) To establish and validate comprehensive microarrays of T. cruzi genes expressed during differentiation of epimastigotes into metacyclic trypomastigotes. 2) To use these DNA microarrays to identify T. cruzi genes that are differentially expressed during metacyclogenesis. 3) To use known potentiators of T. cruzi metacyclogenesis to identify 5-10 candidate genes that trigger, control or direct the differentiation process. 4) To document the function of these regulatory genes by in silico analysis, overexpression, knockout of the endogenous genes, or regulated inhibition of expression (e.g., using RNAi), using our regulated T. cruzi gene expression system. We anticipate identifying several hundred differentially regulated genes in Specific Aim #2. In Specific Aim #3, we will screen out most of the genes that are not directly causal in the differentiation process and select 5-10 candidates for regulatory genes for further analysis. In Specific Aim #4, we will use our regulatable T. cruzi genetic system and RNAi to establish the functions and roles of the differentially expressed genes that play a probable Website: http://crisp.cit.nih.gov/crisp/Crisp_Query.Generate_Screen •
Project Title: GENETIC ANALYSIS OF PURINE METABOLISM IN LEISHMANIA DONO Principal Investigator & Institution: Ullman, Buddy; Professor; Biochem and Molecular Biology; Oregon Health & Science University Portland, or 972393098 Timing: Fiscal Year 2002; Project Start 01-JUN-1983; Project End 31-MAR-2003 Summary: Amalgamating tools of molecular biology, genetics, biochemistry, structural biology, and immunochemistry, this proposal offers a thorough interdisciplinary analysis of three key enzymes of the purine salvage pathway of Leishmania. These enzymes are hypoxanthine-guanine phosphoribosyltransferase (HGPRT), adenine phosphoribosyltransferase (APRT), and xabthine phosphoribosyltransferase (XPRT). As protozoan parasites are auxotrophic for purines, HGPRT, APRT, and XPRT provide an important, if not vital, nutritional function for the parasite, and HGPRT initiates the intracellular metabolism of allopurinol, a lead compound that has shown therapeutic efficacy in both leishmaniasis and Chagas disease. The proposed investigations constitute a logical step in the validation of these enzymes as potential therapeutic targets and in the implementation of a rational, structure-based strategy of drug discovery, and ultimately drug design, for the treatment and prophylaxis of leishmaniasis and other diseases of parasitic origin. The first objective of this application is to determine the contributions of HGPRT, APRT, XPRT, and adenosine kinase (AK) to purine salvage in L. donovani promastigotes by phenotypic characterization of deltaxprt mutants that will be constructed by targeted gene replacement in wild type, deltahgprt, deltaaprt, deltahgprt/deltaaprt, deltahgprt/ak, deltaaprt/ak, and deltahgprt/deltaaprt/ak genetic backgrounds. Whether HGRPT, APRT, or XPRT function is essential for infectivity or virulence will be tested by generating null mutants in the infective M379 L. mexicana strain. The second specific aim entails a detailed biochemical and structural characterization of the HGRPT, APRT, and XPRT proteins. The first component of Specific Aim II consists of an evaluation of the HGPRT and XPRT molecular models and the APRT structure by site-directed mutagenesis of key amino acids that are conjectured to be involved in catalysis or substrate binding and biochemical characterization of the genetically altered proteins. The second aspect of this aim is to supplement the structure-function studies on HGPRT and XPRT via the introduction of crystallographic methods with the ultimate intention of resolving a 3-D structure of a leishmanial HGPRT or XPRT protein. The final specific aim is to ascertain the intracellular location of the APRT and XPRT proteins by subcellular fractionation of
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parasite lysates and by immunofluorescence and immunoelectron microscopy on intact cells. Website: http://crisp.cit.nih.gov/crisp/Crisp_Query.Generate_Screen •
Project Title: GRNA/MRNA INTERACTIONS IN TRYPANSOME RNA EDITING Principal Investigator & Institution: Koslowsky, Donna J.; Associate Professor; Microbiology and Public Health; Michigan State University 301 Administration Bldg East Lansing, Mi 48824 Timing: Fiscal Year 2002; Project Start 01-JAN-2001; Project End 31-DEC-2005 Summary: RNA editing in Trypanosoma brucei is a process that inserts / deletes uridylate residues (U) from mitochondrial pre-mRNA molecules. This phenomenon produces mature mRNAs by creating open reading frames, correcting frame shifts and creating signals for translational initiation and termination. The placement of Us is guided by a small RNA molecule (the guide (g) - RNA) which is complementary to portions of the mature mRNA. While the gRNA is known the carry the information for the editing process, little is known about how the gRNAs are used to direct the editing process. All of the gRNAs identified to date have defined 5' anchor sequences, guiding sequences and a non-encoded 3' uridine tail. The overall objective of this proposal is to understand how the different gRNA elements contribute to the editing process, how they interact with the pre-edited mRNA during editing and ultimately how the gRNA is utilized to direct editing. This objective will be approached using three avenues of research: 1) an analysis of the secondary structure interactions between gRNA and mRNA during the editing process. The extent of the gRNAs interactions with the mRNA will be determined by combining photoaffinity cross linking with structure probing techniques. Defining the structures of the gRNA and the mRNA as they interact during the editing process will help lead to a molecular understanding for the role of the gRNAs in the editing process. 2) An analysis of the tertiary structure of RNAs and proteins in the editing complex. The cross linking patterns of photo-agents attached at homologous sites in different gRNAs and mRNAs will be analyzed to determine if these RNAs contain a common, core tertiary structure. Using site-specific cross linking techniques, the positions of editing proteins in relation to specific regions of the gRNA and mRNA will be analyzed. 3) A determination of the roles of sequence and structure in the kinetics of gRNA/mRNA association. The contribution both sequence and structure make in the overall kinetics of RNA interaction will be analyzed using native and temperature gradient gel electrophoresis and surface plasmon resonance technology. The binding of the gRNA to the mRNA is the fundamental step in RNA editing. An understanding of the nature and relative importance of the elements, which confer specificity on this interaction, is critical to our understanding of the editing process. This research will allow us to begin to understand the structural function relationship of RNAs and protein within the editing complex and greatly enhance our understanding of the mechanism involved in the transfer of information from one RNA molecule to another. Members of the kinetoplastida are the causative agents of African sleeping sickness, Chagas disease and leishmaniasis. Understanding kRNA editing, which is unique to these organisms, will contribute to the fundamental knowledge of the parasite and may lead to the development of new strategies for disease intervention and control. Website: http://crisp.cit.nih.gov/crisp/Crisp_Query.Generate_Screen
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Project Title: NEURON SURVIVAL IN CHAGAS DISEASE Principal Investigator & Institution: Pereira, Miercio A.; Professor; Pathology; Tufts University Boston Boston, Ma 02111 Timing: Fiscal Year 2002; Project Start 01-JUL-2000; Project End 30-JUN-2005 Summary: (Adapted from the Investigator's Abstract): Chagas disease, caused by the protozoan Trypanosoma cruzi, progresses through 3 stages: 1) acute disease, characterized by robust parasite growth, immunological disturbances, and peripheral neural degeneration; 2) indeterminate phase, asymptomatic and featuring extensive regeneration of neurons; and 3) chronic phase, characterized by immunological alterations and pronounced degeneration of neurons in the heart and GI tract. Most patients remain asymptomatic and with signs of neuronal regeneration for decades, but for enigmatic reasons, some (
