Digital Commons Network^™

The Effect Of Febrile Temperature On Plasmodium Falciparum, Heidi Sue Porter

Theses and Dissertations

Previously it has been shown that cultures of Plasmodium falciparum died following exposure to a febrile temperature of 40°C, as demonstrated by a decrease in parasitemia of the following generation. In the current study, the effect of 40°C treatment on culture media, erythrocytes, and parasite glucose consumption, were ruled out as possible influences on parasite death, demonstrating that 40°C impacted the parasites directly. Metabolic profiling of DNA synthesis, protein synthesis, and glucose utilization during exposure to 40°C clearly indicated that febrile temperatures had direct effect on major metabolic pathways and parasite development, beginning 20-24 hr after erythrocyte invasion. The ring …

Quantitative Dissection Of Clone-Specific Growth Rates In Cultured Malaria Parasites, Heather B. Reilly Ayala, Hongjian Wang, John A. Steuter, Anastasia M. Marx, Michael T. Ferdig

Faculty Publications - Department of Biological & Molecular Science

Measurement of parasite proliferation in cultured red blood cells underpins many facets of malaria research, from drug sensitivity assays to assessing the impact of experimentally altered genes on parasite growth, virulence, and fitness. Pioneering efforts to grow Plasmodium falciparum in cultured red blood cells revolutionized malaria research and spurred the development of semi-high throughput growth assays using radio-labeled hypoxanthine, an essential nucleic acid precursor, as a reporter of whole-cycle proliferation (Trager and Jensen, 1976; Desjardins et al., 1979). Use of hypoxanthine (Hx) and other surrogate readouts of whole-cycle proliferation remains the dominant choice in malaria research. While amenable to high-throughput …

Anopheles Gambiae Purine Nucleoside Phosphorylase: Catalysis, Structure And Inhibition, Erika Taylor, Agnes Rinaldo-Matthis, Lei Li, Mahmoud Ghanem, Keith Hazleton, M. Belen Cassera, Steven Almo, Vern Schramm

Erika A. Taylor, Ph.D.

The purine salvage pathway of Anopheles gambiae, a mosquito that transmits malaria, has been identified in genome searches on the basis of sequence homology with characterized enzymes. Purine nucleoside phosphorylase (PNP) is a target for the development of therapeutic agents in humans and purine auxotrophs, including malarial parasites. The PNP from Anopheles gambiae (AgPNP) was expressed in Escherichia coli and compared to the PNPs from Homo sapiens (HsPNP) and Plasmodium falciparum (PfPNP). AgPNP has kcat values of 54 and 41 s-1 for 2'-deoxyinosine and inosine, its preferred substrates, and 1.0 s-1 for guanosine. However, the chemical step is fast for …

The Plasmodium Falciparum Chloroquine Resistance Transporter, Pfcrt, Mediates The Activity Of Chloroquine-Resistance Reversal Agents In The Malaria Parasite, Kristin Lane

Biological Sciences Theses & Dissertations

Chloroquine (CQ) resistant Plasmodium falciparum is a serious problem affecting 3.2 billion people in over 100 countries today. Most endemic malarious countries are among the poorest in the world and lack the resources to replace the inexpensive and highly effective CQ. CQ resistance (CQR) reversal agents are a potentially inexpensive solution to restoring CQ efficacy. CQR reversal agents are drugs that have little to no antimalarial activity alone, but in combination with CQ, they increase dmg accumulation in the parasite and enhance the sensitivity to CQ in CQR parasites. PfCRT is a putative transporter located on the parasite digestive vacuole …

A Member Of The Novel Fikk Family Of Plasmodium Falciparum Putative Protein Kinases Exhibits Diacylglycerol Kinase Activity And Is Exported To The Host Erythrocyte, David Floyd Curtis

Electronic Theses and Dissertations

Plasmodium falciparum is one of four species known to cause malaria in humans and is the species that is associated with the most virulent form of the disease. Malaria causes nearly two million deaths each year, many of these occurring among children in under-developed countries of the world. One reason for this is the prevalence of drug resistant strains of malaria that mitigate the efficacy of existing drugs. Hence, the identification of a new generation of pharmacological agents for malaria is extremely urgent. The recent identification of a group of novel protein kinases within the Plasmodium falciparum genome has provided …

Evaluation Of The Performance Of K-Otab (Deltamethrin Tablet Formulation) Impregnated Bednets Against The Malaria Vector Anopheles (Cellia) Superpictus Grassi 1899 (Diptera: Culicidae) Under Laboratory Conditions, Fati̇h Mehmet Şi̇mşek, Seli̇m Süalp Çağlar, Si̇nan Kaynaş, Bülent Alten

Turkish Journal of Zoology

The efficacy of K-OTAB (deltamethrin-tablet formulation) impregnated bednets was evaluated against the malaria vector Anopheles (Cellia) superpictus Grassi 1899 (Diptera: Culicidae) under laboratory conditions. The experiments were carried out with 3 main tests: susceptibility, bioassay, and washing tests. Deltamethrin treated nets in WHO test kits in susceptibility test 1 showed remarkable efficacy (89.5%) 1 h after the treatment and efficacy was 100% at the end of 24 h. The results demonstrated significant differences in mortality between different time intervals. Average mortality started to increase just after 15 min; it was 61% after 30 min, reaching 82% after 45 min and …

Design, Synthesis, And Evaluation Of 10-N-Substituted Acridones As Novel Chemosensitizers In Plasmodium Falciparum, Jane X. Kelly, Martin J. Smilkstein, Roland A. Cooper, Kristin D. Lane, Robert A. Johnson, Aaron Janowsky, Rozalia A. Dodean, David J. Hinrichs, Rolf Winter, Michael Riscoe

Biological Sciences Faculty Publications

A series of novel 10-N-substituted acridones, bearing alkyl side chains with tertiary amine groups at the terminal position, were designed, synthesized, and evaluated for the ability to enhance the potency of quinoline drugs against multidrug-resistant (MDR) Plasmodium falciparum malaria parasites. A number of acridone derivatives, with side chains bridged three or more carbon atoms apart between the ring nitrogen and terminal nitrogen, demonstrated chloroquine (CQ)-chemosensitizing activity against the MDR strain of P. falciparum (Dd2). Isobolograrn analysis revealed that selected candidates demonstrated significant synergy with CQ in the CQ-resistant (CQR) parasite Dd2 but only additive (or indifferent) interaction in the CQ-sensitive …

Mutations In Transmembrane Domains 1, 4 And 9 Of The Plasmodium Falciparum Chloroquine Resistance Transporter Alter Susceptibility To Chloroquine, Quinine And Quinidine, Roland A. Cooper, Kristan D. Lane, Bingbing Deng, Jianbing Mu, Jigar J. Patel, Thomas E. Wellems, Xinzhuan Su, Michael T. Ferdig

Biological Sciences Faculty Publications

Mutations in the Plasmodium falciparum chloroquine (CQ) resistance transporter (PfCRT) can result in verapamil-reversible CQ resistance and altered susceptibility to other antimalarials. PfCRT contains 10 membrane-spanning domains and is found in the digestive vacuole (DV) membrane of intraerythrocytic parasites. The mechanism by which PfCRT mediates CQ resistance is unclear although it is associated with decreased accumulation of drug within the DV. On the permissive background of the P. falciparum 106/1(K76) parasite line, we used single-step drug selection to generate isogenic clones containing unique pfcrt point mutations that resulted in amino acid changes in PfCRT transmembrane domains 1 (C72R, K76N, K76I …

Intellectual Property Management Strategies To Accelerate The Development And Access Of Vaccines And Diagnostics: Case Studies On Pandemic Influenza, Malaria And Sars, Anatole Krattiger, Stanley P. Kowalski, Robert Eiss, Anthony Taubman

Law Faculty Scholarship

Achieving global access to vaccines, diagnostics, and pharmaceuticals remains a challenge. Throughout the developing world, intellectual property (IP) constraints complicate access to critically essential medical technologies and products. Vaccines for malaria and pandemic strains of influenza, as well as diagnostic and vaccine technologies for SARS, are not only relevant to global public health but are particularly critical to the needs of developing countries. A global access solution is urgently needed. This article offers a timely case‐by‐case analysis of preliminary patent landscape surveys and formulates options via patent pools and other forms of creative IP management to accelerate development and access. …

Seasonal Frequency And Relative Density Of Larval Populations Of Mosquito Species (Diptera: Culicidae) In Şanlıurfa Province, Turkey, Fati̇h Mehmet Şi̇mşek

Turkish Journal of Zoology

This research was conducted between June 2000 and August 2002 in 2 regions of Şanlıurfa: one (IR) where there was substantial irrigated agriculture due to the Southeastern Anatolia Project and another (MR) where a high number of malaria cases were determined every year. Ten species, namely Anopheles (Anopheles) claviger Meigen, 1804, An. (Anopheles) sacharovi Favre, 1903, An. (Cellia) superpictus Grassi, 1899, Culex (Neoculex) martinii Medschid, 1930, Cx. (Culex) pipiens Linnaeus, 1758, Cx. (Neoculex) territans Walker, 1856, Cx. (Culex) theileri Theobald, 1903, Culiseta (Allotheobaldia) longiareolata Macquart, 1938, Ochlerotatus (Ochlerotatus) caspius Pallas, 1771 and Uranotaenia (Pseudoficalbia) unguiculata Edwards, 1903, were recorded in …

Emerging Vector-Borne Diseases In A Changing Environment, Nurdan Özer

Turkish Journal of Biology

Vector-borne infectious diseases are emerging or resurging as a result of changes in public health policy, demographic and societal changes, insecticide and drug resistance, shift in emphasis from prevention to emergency response, genetic changes in pathogens in the last two decades of the twentieth century. Climate changes also can influence the emergence and reemergence of these diseases which are malaria, dengue, yellow fever, plague, filariasis, louse-borne typhus, lyme disease, trypanosomiasis, leishmaniasis and viral diseases. West Nile virus is just the latest example of this type of invasion by exotic virus. This paper will provide an overview of the distribution, reasons …

Characterization Of Protein Prenyltransferases And Protein Prenylation In Plasmodium Falciparum, Thiago Gaspar Dasilva

Electronic Theses and Dissertations

Malaria kills at least one million people each year, mostly children - a death every 30 seconds. Almost one half of the world population is at risk from malaria. Antimalarial drugs are the only means for the treatment of about 500 million annual global malaria cases. Because of prevalent drug-resistance it is extremely urgent to identify new drug targets. Many proteins involved in eukaryotic signal transduction and cell cycle progression undergo post-translational lipid modification by a prenyl group. Protein prenyltransferases, which catalyze the post-translational prenyl modification, have been established as a target for anticancer therapy. Research done in our laboratory …

Dissecting The Loci Of Low-Level Quinine Resistance In Malaria Parasites, Michael T. Ferdig, Roland A. Cooper, Jianbing Mu, Bingbing Deng, Deirdre A. Joy, Xin-Zhuan Su, Thomas E. Wellems

Biological Sciences Faculty Publications

Quinine (QN) remains effective against Plasmodium falciparum, but its decreasing efficacy is documented from different continents. Multiple genes are likely to contribute to the evolution of QN resistance. To locate genes contributing to QN response variation, we have searched a P. falciparum genetic cross for quantitative trait loci (QTL). Results identify additive QTL in segments of chromosomes (Chrs) 13, 7 and 5, and pairwise effects from two additional loci of Chrs 9 and 6 that interact, respectively, with the QTL of Chrs 13 and 7. The mapped segments of Chrs 7 and 5 contain pfcrt, the determinant of …

Multiple Transporters Associated With Malaria Parasite Responses To Chloroquine And Quinine, Jianbing Mu, Michael T. Ferdig, Xiaorong Feng, Deirdre A. Joy, Junhui Duan, Tetsuya Furuya, G. Subramanian, L. Aravind, Roland A. Cooper, John C. Wootton, Momia Xiong, Xin-Zhuan Su

Biological Sciences Faculty Publications

Mutations and/or overexpression of various transporters are known to confer drug resistance in a variety of organisms. In the malaria parasite Plasmodium falciparum, a homologue of P-glycoprotein, PfMDR1, has been implicated in responses to chloroquine (CO), quinine (ON) and other drugs, and a putative transporter, PfCRT, was recently demonstrated to be the key molecule in CO resistance. However, other unknown molecules are probably involved, as different parasite clones carrying the same pfcrt and pfmdr1 alleles show a wide range of quantitative responses to CO and ON. Such molecules may contribute to increasing incidences of ON treatment failure, the molecular basis …

Cultivating Killers: [Dr. William Trager], Fulvio Bardossi, Judith N. Schwartz

Rockefeller University Research Profiles

Rockefeller University Research Profiles are a series of scientific profiles that were published quarterly, from 1980-1990, by the Rockefeller University. Each issue features the research and achievements of an individual Rockefeller University scientist.

Dr. Nott's Theory Of Insect Causation Of Disease, William A. Riley

Harold W. Manter Laboratory: Library Materials

Excerpt:

The danger in using isolated sentences from an article as a basis for interpreting the author's theories, is generally recognized, but sometimes the most careful workers fall into the trap. Once the mistaken interpretation is published, it may be copied over and over again until it rises to the dignity of a dogma.

A striking illustration is afforded by the practical unanimity with which writers on the subject of insects and disease credit Dr. Josiah Nott with being the earliest to formulate definitely the theory of mosquito transmission of yellow fever.

Nuttall, in his classic monograph On the Role …