Download or read book Identification and Characterization of Novel Drug Resistance Loci in Plasmodium Falciparum written by Daria Natalie Van Tyne and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Malaria has plagued mankind for millennia. Antimalarial drug use over the last century has generated highly drug-resistant parasites, which amplify the burden of this disease and pose a serious obstacle to control efforts. This dissertation is motivated by the simple fact that malaria parasites have become resistant to nearly every antimalarial drug that has ever been used, yet the precise genetic mechanisms of parasite drug resistance remain largely unknown. Our work pairs genomics-age technologies with molecular biology, genetics and molecular epidemiology in order to identify and characterize novel genes that contribute to drug resistance in P. falciparum.
Download or read book Multi drug Resistance in Malaria written by Pritha Sen and published by . This book was released on 2001 with total page 162 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Discovery and Characterization of a Novel Class of Metabolic Regulators in the Malaria Parasite Plasmodium Falciparum written by Ann M. Guggisberg and published by . This book was released on 2016 with total page 260 pages. Available in PDF, EPUB and Kindle. Book excerpt: The malaria parasite, Plasmodium falciparum, infects hundreds of millions of people per year and causes hundreds of thousands of deaths. Within the host red blood cell, the parasite relies on glycolysis for energy and synthesis of essential biomolecules. One such anabolic fate of glucose is the synthesis of isoprenoids, a broad and essential class of compounds that participate in a variety of cellular functions. In the face of ever-evolving drug resistance, new inhibitors and better understanding of parasite metabolism are required. The antibiotic fosmidomycin (FSM) targets the methylerythritol phosphate pathway for isoprenoid synthesis and is a well-validated inhibitor of P. falciparum growth. A forward selection for FSM resistance generated a number of parasite strains with increased drug tolerance. We identify mutations in two members of the haloacid dehalogenase-like hydrolase (HAD) superfamily, PfHAD1 and PfHAD2, as causal for resistance. Enzymatic characterization and metabolic profiling reveal that these mutations are deleterious and confirm the role of PfHAD1 and PfHAD2 as novel negative regulators of glucose and isoprenoid metabolism. Despite their homology and shared role in FSM resistance, PfHAD1, a sugar phosphatase, and PfHAD2, a purine nucleotidase, appear to mediate FSM resistance via distinct enzymatic mechanisms. To further understand the role of PfHADs as metabolic regulators, we harness a growth defect in FSM-resistant PfHAD2 mutants to select for suppressors of FSM resistance. We identify suppressor mutations in the key glycolytic enzyme phosphofructokinase (PfPFK9) and describe the effect of these mutations on enzyme function and parasite metabolism. Given its safety in humans and its specificity as a MEP pathway inhibitor, FSM is a strong candidate for clinical development and is currently being evaluated in clinical trials as part of an antimalarial combination therapy. Unfortunately, previous studies have observed high rates of recrudescence following FSM treatment when paired with the antibiotic clindamycin (CLN). To understand whether any genetic changes correlate with recrudescence, we performed whole genome sequencing on patient parasite populations before and after recrudescence. We demonstrate the use of a selective amplification method to amplify and sequence parasite genomes from blood spots. Our genotyping does not reveal any genetic changes responsible for recrudescence, but rather support the hypothesis that FSM-CLN treatment failure is due to formulation or partner drug selection. We encourage further development of FSM and other MEP pathway inhibitors as antimalarial therapies.
Download or read book Characterization of Plasmodium Falciparum Resistance to Novel Drugs written by Sonia Edayé and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: "Plasmodium falciparum is the deadly protozoan parasite responsible for malaria. Malaria is one of the most important infectious diseases that has been raging for millennia and affecting almost half of the world's population. The treatment regimen that was based on quinoline drugs such as chloroquine (CQ), was efficient for decades. Nowadays, the use of this class of drugs is doomed to failure due to the emergence of quinoline-resistant parasites. Today, artemisinin-based combination therapies (ACTs) are the first-line drugs for uncomplicated falciparum malaria treatment. ACTs improve the cure rate of malaria and thus are seen as efficient treatment against uncomplicated forms of the disease. Despite their efficiency, these drugs are currently facing the development of resistance. PfCRT and PfMDR1, which are membrane transporters, have been shown to be involved in malaria parasites drug resistance. To tackle the inefficiency of existing drugs in regard to the development of resistance, alternative therapies must be discovered. In this thesis, antimalarial activity of novel potential drugs against P. falciparum is assessed and the interaction of these drugs with PfCRT and PfMDR1 is determined. Furthermore, because many ABC transporter genes play a key role in drug resistance, the characterization of an ABC transporter member of the ABCG family in Plasmodium is addressed and its role in drug resistance investigated.In the first part of this thesis, MK571 (a quinoline analogue) activity against P. falciparum parasites is investigated. MK571 is found to be more toxic to most of the CQ-resistant strains than to the CQ-sensitive strains. In addition, we determine that MK571 is not a substrate of PfCRT as are other quinoline drugs, but is instead a substrate of PfMDR1. Therefore, it can be a good complement to existing quinoline drugs in the treatment of uncomplicated malaria. In the second part, novel compound analogues of chloroquine are tested for their antimalarial activity against CQ-sensitive and -resistant parasites. Although chloroquine analogues tested possess the quinoline ring structure of chloroquine, they are less efficient than chloroquine and are not substrates of PfCRT. One of the analogues (3-ICQ) reverses the resistance of CQ-resistant strains to chloroquine and therefore, could be used in combination with chloroquine in cases of CQ-resistant malaria. In the third part of the thesis we conduct the characterization of PfABCG, the sole member of the P. falciparum ABCG family. The characterization study demonstrates that PfABCG is localized on the parasite plasma membrane and is expressed throughout the asexual life cycle of the parasite. In addition, PfABCG is differentially expressed in various Plasmodium strains. This expression does not correlate with the resistance to chloroquine but to the sensitivity of the parasite to an antihistaminic drug named ketotifen. Overall, this thesis sheds light on challenges and understanding of the complex resistance machinery deployed by the P. falciparum parasite from novel drug discovery to characterization of proteins. " --
Download or read book Identification and Characterization of Novel Inhibitors of Plasmodium Falciparum Hemozoin Formation written by Margaret Andrews Rush and published by . This book was released on 2009 with total page 374 pages. Available in PDF, EPUB and Kindle. Book excerpt: We've conducted a series of experiments to determine if the seventeen CFHCS hits inhibit P. falciparum growth by inhibiting heme crystallization, including heme binding assays, structure activity relationship studies, investigations of drug sensitivity in multidrug resistant parasites and experiments to determine if hemoglobin protease inhibitors antagonize the activity of the CFHCS hits. Additionally, we conducted phenotypic studies to determine if these compounds changed parasite morphology, especially the morphology of the hemozoin crystal and parasite food vacuole. Each of these assays has been previously described to support the mechanism of action of the quinoline antimalarials. Through these experiments we were able to rule out BCM as the mechanism of action of at least one compound and provide strong evidence to support this mechanism for nine compounds. Our finding also have interesting implications for the development of drugs which act by inhibiting BCM, one of the most important drug targets in the malaria parasite.
Download or read book Characterization of Drug resistant Isolates of Plasmodium Falciparum written by and published by . This book was released on 1997 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Identification and Characterization of MB2 written by Thanh Viet Nguyen and published by . This book was released on 2001 with total page 218 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Advances in Malaria Research written by Deepak Gaur and published by John Wiley & Sons. This book was released on 2016-12-27 with total page 611 pages. Available in PDF, EPUB and Kindle. Book excerpt: Thoroughly reviews our current understanding of malarial biology Explores the subject with insights from post-genomic technologies Looks broadly at the disease, vectors of infection, and treatment and prevention strategies A timely publication with chapters written by global researchers leaders
Download or read book The Malaria Genome Projects written by Irwin W. Sherman and published by World Scientific. This book was released on 2012 with total page 389 pages. Available in PDF, EPUB and Kindle. Book excerpt: The year 2012 marks the tenth anniversary of the announcement of the genome sequence of the human malaria parasite Plasmodium falciparum and that of its mosquito vector Anopheles. The genome sequences were a result of the Plasmodium falciparum Genome Project. This book covers in detail the biology of malaria parasites and the mosquitoes that transmit the disease, how the Genome Project came into being, the people who created it, and the cadre of scientists who are attempting to see the promise of the Project realized. The promise was: a more complete understanding of the genes of the parasite (and its vector) would provide a rational basis for the development of antimalarial drugs and vaccines, allow a better understanding of the regulation of the complex life cycle in the red blood and liver cells of the human, identify the genes the parasite uses to thwart the host immune response and the ways in which the parasite evades cure by drug treatments, as well as leading to more effective measures of control transmission. The hope was that cracking the genetic code of Plasmodium and Anopheles would reveal the biochemical Achilles heel of the parasite and its vector, leading to the development of novel drugs and better methods of control, and by finding the targets of protective immunity could result in the manufacture of effective vaccines. Through a historic approach, this book will allow for those new to the field, or those with insufficient background in the sciences, to have an easier entry point. Even scientists already working in the field may better appreciate how discoveries made in the past can impact the direction of future research.
Download or read book The Zoological Record written by and published by . This book was released on with total page 1432 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Resistance of Malaria Parasites to Drugs written by World Health Organization. Scientific Group on Resistance of Malaria Parasites to Drugs and published by . This book was released on 1965 with total page 76 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Handbook of Antimicrobial Resistance written by Matthias Gotte and published by Springer. This book was released on 2018-02-12 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: While many volumes have been written about various aspects of antimicrobial resistance, this book is a comprehensive reference work. All manifestations of resistance are addressed: viral; bacterial, parasitical and fungal are given dedicated sections. The underlining molecular mechanisms, which depend not only on the microbe but on the specific drug (target), are highly diverse. This work discusses and compares the biological, biochemical and structural aspects of resistance and its evolution.
Download or read book Drug Resistance in Bacteria Fungi Malaria and Cancer written by Gunjan Arora and published by Springer. This book was released on 2017-03-21 with total page 629 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is a compilation of past and recent knowledge in the field of emerging drug resistance. The book covers major aspects of drug resistance in bacteria, fungi, malaria, and cancer.Human survival on earth is constantly threatened by disease and syndrome. From the early days, the aim of research in medicine was to find therapeutic agents that can improve the quality of human life. Although humans are dependent on natural compounds from early days their dependence of drugs increased excessively in last century. The advances in chemistry and biology have helped researchers to identify the drugs that have improved treatment of many diseases. The primary factor for treatment of these diseases is dependent on the efficacy of drugs available. The development of resistance to these drugs is one of the major hindrances. Although there are number of books available on this topic, “drug resistance” biology across kingdoms has never been discussed in a coherent way.
Download or read book Antibiotic Drug Resistance written by José-Luis Capelo-Martínez and published by John Wiley & Sons. This book was released on 2019-09-24 with total page 730 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents a thorough and authoritative overview of the multifaceted field of antibiotic science – offering guidance to translate research into tools for prevention, diagnosis, and treatment of infectious diseases. Provides readers with knowledge about the broad field of drug resistance Offers guidance to translate research into tools for prevention, diagnosis, and treatment of infectious diseases Links strategies to analyze microbes to the development of new drugs, socioeconomic impacts to therapeutic strategies, and public policies to antibiotic-resistance-prevention strategies
Download or read book Chimpanzees in Biomedical and Behavioral Research written by National Research Council and published by National Academies Press. This book was released on 2011-12-05 with total page 200 pages. Available in PDF, EPUB and Kindle. Book excerpt: For many years, experiments using chimpanzees have been instrumental in advancing scientific knowledge and have led to new medicines to prevent life-threatening and debilitating diseases. However, recent advances in alternate research tools have rendered chimpanzees largely unnecessary as research subjects. The Institute of Medicine, in collaboration with the National Research Council, conducted an in-depth analysis of the scientific necessity for chimpanzees in NIH-funded biomedical and behavioral research. The committee concludes that while the chimpanzee has been a valuable animal model in the past, most current biomedical research use of chimpanzees is not necessary, though noted that it is impossible to predict whether research on emerging or new diseases may necessitate chimpanzees in the future.
Download or read book Parasite Genomics written by Luis M. de Pablos and published by Humana. This book was released on 2021-07-28 with total page 336 pages. Available in PDF, EPUB and Kindle. Book excerpt: This detailed book provides a comprehensive series of innovative research techniques and methodologies applied to the parasite genomics research area, all applying different approaches to analyzing parasite genomes and furthering the study of genetic complexity and the mechanisms of regulation. Beginning with chapters on novel sequencing and the bioinformatics pipeline, the volume continues by exploring diagnostic approaches using genomic tools, host-parasite interactions, as well as the genomics of parasite-derived extracellular vesicles. Written for the highly successful Methods in Molecular Biology series, chapters include introductions to their respective topics, lists of the necessary materials and reagents, step-by-step, readily reproducible laboratory protocols, and tips on troubleshooting and avoiding known pitfalls. Authoritative and practical, Parasite Genomics: Methods and Protocols creates a detailed picture of genomic approaches for researchers seeking a better understanding of characterizing parasite nucleic acid content.
Download or read book Rodent Malaria written by R. Killick-Kendrick and published by Elsevier. This book was released on 2012-12-02 with total page 435 pages. Available in PDF, EPUB and Kindle. Book excerpt: Rodent Malaria reviews significant findings concerning malaria parasites of rodents, including their taxonomy, zoogeography, and evolution, along with life cycles and morphology; genetics and biochemistry; and concomitant infections. This volume is organized into eight chapters and begins by sketching out the history of the discovery of rodent as well as aspects of parasitology, immunology, and chemotherapy. These concepts are investigated two decades following Ignace Vincke's major discovery and Meir Yoeli's successful establishment of the method of cyclical transmission of the parasite. The following chapters focus on the taxonomy and systematics of the subgenus Vinckeia, with reference to the concepts of species and subspecies of animals and the degree to which they apply to malaria parasites, in particular to those of rodents. The discussion then shifts to how the rodent malaria parasites provide a unique insight into the subcellular organization of Plasmodium species, the use of rodent malaria as an experimental model to study immunological responses, and infectious agents that interact with malaria parasites. The book concludes with a chapter on malaria chemotherapy, with emphasis on the value of rodent malaria in antimalarial drug screening and the use of antimalarial drugs as biological probes. This book will be of interest to protozoologists and physicians as well as those from other disciplines including biochemistry, immunology, pharmacology, cell biology, and genetics.
