keyword
MENU ▼
Read by QxMD icon Read
search

falciparum polymorphism

keyword
https://www.readbyqxmd.com/read/29332155/prevalence-of-the-pfdhfr-and-pfdhps-mutations-among-asymptomatic-pregnant-women-in-southeast-nigeria
#1
Ekpereonne Esu, Costanza Tacoli, Prabhanjan Gai, Nicole Berens-Riha, Michael Pritsch, Thomas Loescher, Martin Meremikwu
Sulfadoxine-pyrimethamine (SP) is the recommended drug for intermittent preventive treatment of malaria in pregnancy in most of sub-Saharan Africa. Resistance to SP is related to mutations in the dhfr and dhps gene of Plasmodium falciparum. This study determined the prevalence of Pfdhfr and Pfdhps polymorphisms found in asymptomatic pregnant women attending antenatal care in Calabar, Nigeria. From October 2013 to November 2014, asymptomatic pregnant women attending antenatal care clinics were enrolled after obtaining informed consent...
January 13, 2018: Parasitology Research
https://www.readbyqxmd.com/read/29318942/high-prevalence-of-dihydrofolate-reductase-gene-mutations-in-plasmodium-falciparum-parasites-among-pregnant-women-in-nigeria-after-reported-use-of-sulfadoxine-pyrimethamine
#2
Olusola Ojurongbe, Christian N Nguetse, Samuel A Fayemiwo, Catherine O Falade, Taiwo A Ojurongbe, Bolaji N Thomas, Christian G Meyer, Thirumalaisamy P Velavan
This study assesses the prevalence of asymptomatic Plasmodium falciparum parasitemia positivity and P. falciparum dihydrofolate reductase (pfdhfr) mutations in parasite isolates among pregnant women in Southwest Nigeria. Plasmodium falciparum parasitemia was confirmed by microscopy and nested PCR in 200 pregnant women attending antenatal care. The prevalence of pfdhfr polymorphisms was determined by direct sequencing of the gene fragments containing the C50R, N51I, C59R, S108N, and I164L mutations. Information on the use of antimalarial drugs and methods applied to prevent malaria were obtained by a questionnaire...
January 10, 2018: Pathogens and Global Health
https://www.readbyqxmd.com/read/29316929/molecular-identification-of-sulfadoxine-pyrimethamine-resistance-in-malaria-infected-women-who-received-intermittent-preventive-treatment-in-the-democratic-republic-of-congo
#3
Emrah Ruh, Jean Paul Bateko, Turgut Imir, Aysegul Taylan-Ozkan
BACKGROUND: Point mutations in Plasmodium falciparum dihydrofolate reductase (Pfdhfr) and dihydropteroate synthase (Pfdhps) genes which confer resistance to sulfadoxine-pyrimethamine (SP) occur at increasing rates. The present study aimed to identify Pfdhfr and Pfdhps mutations in P. falciparum isolates recovered from women who received two doses of SP during pregnancy in Bandundu, the Democratic Republic of Congo (DRC). METHODS: A total of 48 women with confirmed P...
January 9, 2018: Malaria Journal
https://www.readbyqxmd.com/read/29316927/global-sequence-diversity-of-the-lactate-dehydrogenase-gene-in-plasmodium-falciparum
#4
Phumin Simpalipan, Sittiporn Pattaradilokrat, Pongchai Harnyuttanakorn
BACKGROUND: Antigen-detecting rapid diagnostic tests (RDTs) have been recommended by the World Health Organization for use in remote areas to improve malaria case management. Lactate dehydrogenase (LDH) of Plasmodium falciparum is one of the main parasite antigens employed by various commercial RDTs. It has been hypothesized that the poor detection of LDH-based RDTs is attributed in part to the sequence diversity of the gene. To test this, the present study aimed to investigate the genetic diversity of the P...
January 9, 2018: Malaria Journal
https://www.readbyqxmd.com/read/29279840/pro-inflammatory-cytokine-response-and-genetic-diversity-in-merozoite-surface-protein-2-of-plasmodium-falciparum-isolates-from-nigeria
#5
Olusola Ajibaye, Akinniyi A Osuntoki, Albert Ot Ebuehi, Bamidele A Iwalokun, Emmanuel O Balogun, Kathleen N Egbuna
Background: Polymorphisms in Plasmodium falciparum merozoite surface protein-2 (msp-2) and associated parasite genetic diversity which varies between malaria-endemic regions remain a limitation in malaria vaccine development. Pro-inflammatory cytokines are important in immunity against malaria, understanding the influence of genetic diversity on cytokine response is important for effective vaccine design. Methods: P. falciparum isolates obtained from 300 Nigerians with uncomplicated falciparum malaria at Ijede General Hospital, Ijede (IJE), General Hospital Ajeromi, Ajeromi (AJE) and Saint Kizito Mission Hospital, Lekki, were genotyped by nested polymerase chain reaction of msp-2 block 3 while ELISA was used to determine the pro-inflammatory cytokine response to describe the genetic diversity of P...
2017: Advanced Biomedical Research
https://www.readbyqxmd.com/read/29261755/interaction-between-environment-nutrient-derived-metabolites-and-immunity-a-possible-role-in-malaria-susceptibility-resistance-in-fulani-and-dogon-of-mali
#6
Karim Traore, Mahamadou A Thera, Anne-Lise Bienvenu, Charles Arama, Guillaume Bonnot, Adeline Lavoignat, Ogobara K Doumbo, Stephane Picot
The role of some nutrient-derived metabolites on the innate and adaptive immune responses is now established. Global research approach investigating the interplay between environment, lifestyle and the host's immune responses is crucial in the understanding of malaria susceptibility. Advanced Glycation end products (AGE), which are food-derived metabolites result from the link between reducing sugar and amino group of proteins, lipids or nucleic acids. The level of exposure to AGEs varies depending on the type of diet...
2017: PloS One
https://www.readbyqxmd.com/read/29260689/drug-resistant-polymorphisms-and-copy-numbers-in-plasmodium-falciparum-mozambique-2015
#7
Himanshu Gupta, Eusebio Macete, Helder Bulo, Crizolgo Salvador, Marian Warsame, Eva Carvalho, Didier Ménard, Pascal Ringwald, Quique Bassat, Sonia Enosse, Alfredo Mayor
One of the fundamental steps toward malaria control is the use of antimalarial drugs. The success of antimalarial treatment can be affected by the presence of drug-resistant populations of Plasmodium falciparum. To assess resistance, we used molecular methods to examine 351 P. falciparum isolates collected from 4 sentinel sites in Mozambique for K13, pfmdr1, pfcrt, and pfdhps polymorphisms and for plasmepsin2 (pfpm2) and pfmdr1 copy numbers. We found multiple copies of pfpm2 in 1.1% of isolates. All isolates carried K13 wild-type alleles (3D7-like), except 4 novel polymorphisms (Leu619Leu, Phe656Ile, Val666Val, Gly690Gly)...
January 2018: Emerging Infectious Diseases
https://www.readbyqxmd.com/read/29249333/beyond-hemoglobin-screening-for-malaria-host-factors
#8
REVIEW
Elizabeth S Egan
Severe malaria is caused by the Apicomplexan parasite Plasmodium falciparum, and results in significant global morbidity and mortality, particularly among young children and pregnant women. P. falciparum exclusively infects human erythrocytes during clinical illness, and several natural erythrocyte polymorphisms are protective against severe malaria. Since erythrocytes are enucleated and lack DNA, genetic approaches to understand erythrocyte determinants of malaria infection have historically been limited. This review highlights recent advances in the use of hematopoietic stem cells to facilitate genetic screening for malaria host factors...
December 14, 2017: Trends in Genetics: TIG
https://www.readbyqxmd.com/read/29229635/plasmodium-falciparum-recrudescence-two-years-after-a-first-treated-uncomplicated-infection-without-return-in-a-malaria-endemic-area
#9
Denis Malvy, Marylin Torrentino-Madamet, Coralie L'Ollivier, Marie-Catherine Receveur, Fakhri Jeddi, Laurence Delhaes, Renaud Piarroux, Pascal Millet, Bruno Pradines
We report here evidence, confirmed by the lack of travel activity outside of France and genetic diversity analysis using polymorphic microsatellite markers, that Plasmodium falciparum malaria infection effectively treated with an artemisinin-based combination can remain dormant and relapse during pregnancy at least 2 years after treatment.
December 11, 2017: Antimicrobial Agents and Chemotherapy
https://www.readbyqxmd.com/read/29224404/edip-the-epitope-dilution-phenomenon-lessons-learnt-from-a-malaria-vaccine-antigen-and-its-applicability-to-polymorphic-antigens
#10
Kwadwo Asamoah Kusi, Bart W Faber, Gerrit Koopman, Edmond Joseph Remarque
Polymorphism in vaccine antigens poses major challenges to vaccinologists. The Plasmodium falciparum Apical Membrane Antigen 1 (AMA1) poses such a challenge. We found that immunization with a mixture of three variants yielded functional antibody levels to all variants comparable to levels induced by monovalent immunization. The mechanism behind the observed broadening was shown to be an increase in the fraction of cross-reactive antibodies, most likely because strain-specific epitopes are present at lower frequency relative to conserved epitopes...
December 11, 2017: Expert Review of Vaccines
https://www.readbyqxmd.com/read/29215067/profiling-invasive-plasmodium-falciparum-merozoites-using-an-integrated-omics-approach
#11
Krishan Kumar, Prakash Srinivasan, Michael J Nold, J Kathleen Moch, Karine Reiter, Dan Sturdevant, Thomas D Otto, R Burke Squires, Raul Herrera, Vijayaraj Nagarajan, Julian C Rayner, Stephen F Porcella, Scott J Geromanos, J David Haynes, David L Narum
The symptoms of malaria are brought about by blood-stage parasites, which are established when merozoites invade human erythrocytes. Our understanding of the molecular events that underpin erythrocyte invasion remains hampered by the short-period of time that merozoites are invasive. To address this challenge, a Plasmodium falciparum gamma-irradiated long-lived merozoite (LLM) line was developed and investigated. Purified LLMs invaded erythrocytes by an increase of 10-300 fold compared to wild-type (WT) merozoites...
December 7, 2017: Scientific Reports
https://www.readbyqxmd.com/read/29202193/seekdeep-single-base-resolution-de-novo-clustering-for-amplicon-deep-sequencing
#12
Nicholas J Hathaway, Christian M Parobek, Jonathan J Juliano, Jeffrey A Bailey
PCR amplicon deep sequencing continues to transform the investigation of genetic diversity in viral, bacterial, and eukaryotic populations. In eukaryotic populations such as Plasmodium falciparum infections, it is important to discriminate sequences differing by a single nucleotide polymorphism. In bacterial populations, single-base resolution can provide improved resolution towards species and strains. Here, we introduce the SeekDeep suite built around the qluster algorithm, which is capable of accurately building de novo clusters representing true, biological local haplotypes differing by just a single base...
November 30, 2017: Nucleic Acids Research
https://www.readbyqxmd.com/read/29187975/evolutionary-structure-of-plasmodium-falciparum-major-variant-surface-antigen-genes-in-south-america-implications-for-epidemic-transmission-and-surveillance
#13
Virginie Rougeron, Kathryn E Tiedje, Donald S Chen, Thomas S Rask, Dionicia Gamboa, Amanda Maestre, Lise Musset, Eric Legrand, Oscar Noya, Erhan Yalcindag, François Renaud, Franck Prugnolle, Karen P Day
Strong founder effects resulting from human migration out of Africa have led to geographic variation in single nucleotide polymorphisms (SNPs) and microsatellites (MS) of the malaria parasite, Plasmodium falciparum. This is particularly striking in South America where two major founder populations of P. falciparum have been identified that are presumed to have arisen from the transatlantic slave trade. Given the importance of the major variant surface antigen of the blood stages of P. falciparum as both a virulence factor and target of immunity, we decided to investigate the population genetics of the genes encoding "Plasmodium falciparum Erythrocyte Membrane Protein 1" (Pf EMP1) among several countries in South America, in order to evaluate the transmission patterns of malaria in this continent...
November 2017: Ecology and Evolution
https://www.readbyqxmd.com/read/29186116/immune-evasion-of-plasmodium-falciparum-by-rifin-via-inhibitory-receptors
#14
Fumiji Saito, Kouyuki Hirayasu, Takeshi Satoh, Christian W Wang, John Lusingu, Takao Arimori, Kyoko Shida, Nirianne Marie Q Palacpac, Sawako Itagaki, Shiroh Iwanaga, Eizo Takashima, Takafumi Tsuboi, Masako Kohyama, Tadahiro Suenaga, Marco Colonna, Junichi Takagi, Thomas Lavstsen, Toshihiro Horii, Hisashi Arase
Malaria is among the most serious infectious diseases affecting humans, accounting for approximately half a million deaths each year. Plasmodium falciparum causes most life-threatening cases of malaria. Acquired immunity to malaria is inefficient, even after repeated exposure to P. falciparum, but the immune regulatory mechanisms used by P. falciparum remain largely unknown. Here we show that P. falciparum uses immune inhibitory receptors to achieve immune evasion. RIFIN proteins are products of a polymorphic multigene family comprising approximately 150-200 genes per parasite genome that are expressed on the surface of infected erythrocytes...
December 7, 2017: Nature
https://www.readbyqxmd.com/read/29178921/plasmodium-falciparum-kelch-13-mutations-and-treatment-response-in-patients-in-hpa-pun-district-northern-kayin-state-myanmar
#15
Craig A Bonnington, Aung Pyae Phyo, Elizabeth A Ashley, Mallika Imwong, Kanlaya Sriprawat, Daniel M Parker, Stephane Proux, Nicholas J White, Francois Nosten
BACKGROUND: Artemisinin resistance, linked to polymorphisms in the Kelch gene on chromosome 13 of Plasmodium falciparum (k13), has outpaced containment efforts in South East Asia. For national malaria control programmes in the region, it is important to establish a surveillance system which includes monitoring for k13 polymorphisms associated with the clinical phenotype. METHODS: Between February and December 2013, parasite clearance was assessed in 35 patients with uncomplicated P...
November 25, 2017: Malaria Journal
https://www.readbyqxmd.com/read/29177421/endoperoxide-based-compounds-cross-resistance-with-artemisinins-and-selection-of-a-plasmodium-falciparum-lineage-with-a-k13-non-synonymous-polymorphism
#16
Lucie Paloque, Benoit Witkowski, Joël Lelièvre, Manel Ouji, Tanila Ben Haddou, Frédéric Ariey, Anne Robert, Jean-Michel Augereau, Didier Ménard, Bernard Meunier, Françoise Benoit-Vical
Background: Owing to the emergence of multiresistant Plasmodium falciparum parasites in Southeast Asia, along with the impressive decrease in the efficacy of the endoperoxide compound artemisinin and of artemisinin-based combination therapies, the development of novel antimalarial drugs or combinations is required. Although several antiplasmodial molecules, such as endoperoxide-based compounds, are in advanced research or development, we do not know whether resistance to artemisinin derivatives might impact the efficacy of these new compounds...
November 21, 2017: Journal of Antimicrobial Chemotherapy
https://www.readbyqxmd.com/read/29167197/rare-pfcsp-c-terminal-antibodies-induced-by-live-sporozoite-vaccination-are-ineffective-against-malaria-infection
#17
Stephen W Scally, Rajagopal Murugan, Alexandre Bosch, Gianna Triller, Giulia Costa, Benjamin Mordmüller, Peter G Kremsner, B Kim Lee Sim, Stephen L Hoffman, Elena A Levashina, Hedda Wardemann, Jean-Philippe Julien
Antibodies against the central repeat of the Plasmodium falciparum (Pf) circumsporozoite protein (CSP) inhibit parasite activity and correlate with protection from malaria. However, the humoral response to the PfCSP C terminus (C-PfCSP) is less well characterized. Here, we describe B cell responses to C-PfCSP from European donors who underwent immunization with live Pf sporozoites (PfSPZ Challenge) under chloroquine prophylaxis (PfSPZ-CVac), and were protected against controlled human malaria infection. Out of 215 PfCSP-reactive monoclonal antibodies, only two unique antibodies were specific for C-PfCSP, highlighting the rare occurrence of C-PfCSP-reactive B cells in PfSPZ-CVac-induced protective immunity...
November 22, 2017: Journal of Experimental Medicine
https://www.readbyqxmd.com/read/29141757/protein-specific-features-associated-with-variability-in-human-antibody-responses-to-plasmodium-falciparum-malaria-antigens
#18
Eugene W Liu, Jeff Skinner, Tuan M Tran, Krishan Kumar, David L Narum, Aarti Jain, Aissata Ongoiba, Boubacar Traore, Philip L Felgner, Peter D Crompton
The magnitude of antibody responses varies across the individual proteins that constitute any given microorganism, both in the context of natural infection and vaccination with attenuated or inactivated pathogens. The protein-specific factors underlying this variability are poorly understood. In 267 individuals exposed to intense seasonal malaria, we examined the relationship between immunoglobulin G (IgG) responses to 861 Plasmodium falciparum proteins and specific features of these proteins, including their subcellular location, relative abundance, degree of polymorphism, and whether they are predicted to have human orthologs...
October 23, 2017: American Journal of Tropical Medicine and Hygiene
https://www.readbyqxmd.com/read/29140232/country-wide-surveillance-of-molecular-markers-of-antimalarial-drug-resistance-in-senegal-by-use-of-positive-malaria-rapid-diagnostic-tests
#19
MULTICENTER STUDY
Magatte Ndiaye, Doudou Sow, Sidsel Nag, Khadime Sylla, Roger Clement Tine, Jean Louis Ndiaye, Aminata Collé Lo, Oumar Gaye, Babacar Faye, Michael Alifrangis
In Senegal, antimalarial drugs used in treatment and prevention of malaria are one of the main reasons for the current success in controlling malaria. However, the successful control of malaria is highly dependent on continued effectiveness of these drugs which may be compromised by the spread of drug resistance. Therefore, surveillance of drug resistance in the malaria parasites is essential. The objective of this pilot study was to test the feasibility of routinely sampled malaria rapid diagnostic tests (RDTs) at a national scale to assess the temporal changes in the molecular profiles of antimalarial drug resistance markers of Plasmodium falciparum parasites...
November 2017: American Journal of Tropical Medicine and Hygiene
https://www.readbyqxmd.com/read/29132317/development-of-amplicon-deep-sequencing-markers-and-data-analysis-pipeline-for-genotyping-multi-clonal-malaria-infections
#20
Anita Lerch, Cristian Koepfli, Natalie E Hofmann, Camilla Messerli, Stephen Wilcox, Johanna H Kattenberg, Inoni Betuela, Liam O'Connor, Ivo Mueller, Ingrid Felger
BACKGROUND: Amplicon deep sequencing permits sensitive detection of minority clones and improves discriminatory power for genotyping multi-clone Plasmodium falciparum infections. New amplicon sequencing and data analysis protocols are needed for genotyping in epidemiological studies and drug efficacy trials of P. falciparum. METHODS: Targeted sequencing of molecular marker csp and novel marker cpmp was conducted in duplicate on mixtures of parasite culture strains and 37 field samples...
November 13, 2017: BMC Genomics
keyword
keyword
93741
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"