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Publication Metadata only Genetic analysis of the orthologous crt and mdr1 genes in Plasmodium malariae from Thailand and Myanmar(2020-08-31) Yupawadee Pimpat; Naowarat Saralamba; Usa Boonyuen; Sasithon Pukrittayakamee; Francois Nosten; Frank Smithuis; Nicholas P.J. Day; Arjen M. Dondorp; Mallika Imwong; Mahidol Oxford Tropical Medicine Research Unit; Mahidol University; Nuffield Department of Medicine; Medical Action Myanmar© 2020 The Author(s). Background: Plasmodium malariae is a widely spread but neglected human malaria parasite, which causes chronic infections. Studies on genetic polymorphisms of anti-malarial drug target genes in P. malariae are limited. Previous... reports have shown polymorphisms in the P. malariae dihydrofolate reductase gene associated with pyrimethamine resistance and linked to pyrimethamine drug pressure. This study investigated polymorphisms of the P. malariae homologous genes, chloroquinePublication Open Access Genetic diversity of Plasmodium vivax in Kolkata, India.(2006-08-14) Kim, Jung-Ryong; Mallika Imwong; มัลลิกา อิ่มวงศ์; Nandy, Amitabha; Kesinee Chotivanich; เกศินี โชติวานิช; Apichart Nontprasert; อภิชาต นนท์ประเสริฐ; Naowarat Tonomsing; Maji, Ardhendu; Addy, Manjulika; Day, Nick P.J.; White, Nicholas J.; Sasithon Pukrittayakamee; ศศิธร ผู้กฤตยาคามี; Mallika Imwong; Mahidol University. Faculty of Tropical Medicine. Department of Clinical Tropical Medicinecopy genes were selected for a study of genetic diversity in Kolkata strains. METHODS: Blood from 151 patients with P. vivax infection diagnosed in Kolkata between April 2003 and September 2004 was genotyped at three polymorphic loci: the P. vivax...BACKGROUND: Plasmodium vivax malaria accounts for approximately 60% of malaria cases in Kolkata, India. There has been limited information on the genotypic polymorphism of P. vivax in this malaria endemic area. Three highly polymorphic and singlePublication Metadata only Polymorphisms in Pvkelch12 and gene amplification of Pvplasmepsin4 in Plasmodium vivax from Thailand, Lao PDR and Cambodia(2019-04-02) Jureeporn Duanguppama; Vivek Bhakta Mathema; Rupam Tripura; Nicholas P.J. Day; Mayfong Maxay; Chea Nguon; Lorenz Von Seidlein; Mehul Dhorda; Thomas J. Peto; Francois Nosten; Nicholas J. White; Arjen M. Dondorp; Mallika Imwong; Ministry of Health Cambodia; Churchill Hospital; Mahidol University; University of Health Sciences; Mahosot Hospital© 2019 The Author(s). Background: Mutations in Pfkelch13 and Pfplasmepsin2/3 gene amplification are well-established markers for artemisinin and piperaquine resistance in Plasmodium falciparum, a widespread problem in the Greater Mekong Subregion... genes Pvkelch12 and Pvplasmepsin4 (Pvpm4), as candidate resistance markers. Methods: Blood samples from 734 P. vivax patients were obtained from Thailand (n = 399), Lao PDR (n = 296) and Cambodia (n = 39) between 2007 and 2017. Pvkelch12 and Pvpm4Publication Metadata only Limited polymorphism in the dihydropteroate synthetase gene (dhps) of Plasmodium vivax isolates from Thailand(2005-10-01) Mallika Imwong; Sasithon Pukrittayakamee; Qin Cheng; Catrin Moore; Sornchai Looareesuwan; Georges Snounou; Nicholas J. White; Nicholas P.J. Day; Mahidol University; Australian Army Malaria Institute; Churchill Hospital; Institut Pasteur, ParisThe dhps sequences of 55 Plasmodium vivax isolates (39 from Thailand and 16 from elsewhere) revealed mutant Pvdhps at codons 383 and/or 553 (A → G) in 33 isolates, all from Thailand. Mutations of P\dhps and P\dhfr were correlated. Multiple mutations were associated with high-grade sulfadoxine-pyrimethamine resistance. Copyright © 2005, American Society for Microbiology. All Rights Reserved.Publication Metadata only Polymorphic markers for identification of parasite population in Plasmodium malariae(2020-01-28) Vivek Bhakta Mathema; Supatchara Nakeesathit; Watcharee Pagornrat; Frank Smithuis; Nicholas J. White; Arjen M. Dondorp; Mallika Imwong; Mahidol University; Nuffield Department of Clinical Medicine; Medical Action Myanmar. malariae population genetics. Methods: Markers for microsatellite genotyping and pmmsp1 gene polymorphisms were developed and validated in symptomatic P. malariae field isolates from Myanmar (N = 37). Fragment analysis was used to determine allele sizes... (INDEL) and single nucleotide polymorphisms is used for genotyping, but only limited information is available for Plasmodium malariae, an important human malaria species. This study aimed to provide a set of genetic markers to facilitate the study of PPublication Metadata only Genetic polymorphisms in the circumsporozoite protein of Plasmodium malariae show a geographical bias(2018-07-16) Naowarat Saralamba; Mayfong Mayxay; Paul N. Newton; Frank Smithuis; Francois Nosten; Laypaw Archasuksan; Sasithon Pukrittayakamee; Nicholas J. White; Nicholas P.J. Day; Arjen M. Dondorp; Mallika Imwong; University of Oxford; Mahidol University; Nuffield Department of Clinical Medicine; University of Health Sciences; Medical Action Myanmar; Mahosot Hospitalpolymorphisms. Previous reports from Africa have shown heterogeneity within the P. malariae circumsporozoite protein (pmcsp) gene. However, comparative studies from Asian countries are lacking. Here, the genetic polymorphisms in pmcsp of Asian isolates have been... 89 pmcsp sequences were analysed together with 58 previously published pmcsp sequences representing African countries using BioEdit, MEGA6, and DnaSP. Results: Polymorphisms identified in pmcsp were grouped into 3 populations: Thailand, MyanmarPublication Metadata only Genetic diversity of plasmodium vivax merozoite surface protein-3alpha (Pvmsp-3alpha) gene in Jhapa District of Nepal.(2012-03-01) Madhav Adhikari; Samir Ranjitkar; Mette Leth Schousboe; Michael Alifrangis; Mallika Imwong; Dwij Raj Bhatta; Megha Raj Banjara; Mahidol University. vivax population sampled from subjects living in an endemic area of Jhapa District by analyzing the polymorphic merozoite surface protein-3alpha (Pvmsp-3alpha) gene by using PCR-restriction fragment length polymorphism. Three distinct genotypes werePublication Metadata only Molecular correlates of high-level antifolate resistance in Rwandan children with Plasmodium falciparum malaria(2010-01-01) Corine Karema; Mallika Imwong; Caterina I. Fanello; Kasia Stepniewska; Aline Uwimana; Supatchara Nakeesathit; Arjen Dondorp; Nicholas P. Day; Nicholas J. White; National Malaria Control Programme; Mahidol University; Nuffield Department of Clinical MedicineAntifolate drugs have an important role in the treatment of malaria. Polymorphisms in the genes encoding the dihydrofolate reductase and dihydropteroate synthetase enzymes cause resistance to the antifol and sulfa drugs, respectively. Rwanda has... or three pfdhps mutations and 11% had the pfdhfr 164-Leu polymorphism. In the western province, where the cure rates were significantly higher (P < 0.001), the prevalence of multiple resistance mutations was lower and the pfdhfr I164L polymorphismPublication Metadata only Genetic dissociation of three antigenic genes in Plasmodium ovale curtisi and Plasmodium ovale wallikeri(2019-06-01) Naowarat Saralamba; Francois Nosten; Colin J. Sutherland; Ana Paula Arez; Georges Snounou; Nicholas J. White; Nicholas P.J. Day; Arjen M. Dondorp; Mallika Imwong; Centre de Recherche en Immunologie des Infections Virales et des Maladies Auto-Immunes; Universidade Nova de Lisboa, Instituto de Higiene e Medicina Tropical; London School of Hygiene & Tropical Medicine; Mahidol University; Nuffield Department of Clinical Medicinesuggesting a species barrier. In this study we further evaluate such a barrier by assessing polymorphisms in the genes of three vaccine candidate surface protein: circumsporozoite protein/ thrombospon-din-related anonymous-related protein (ctrp... of nucleotide diversity (Pi = 0.02–0.10) was observed in all three genes. Various sizes of tandem repeats were observed in all ctrp, csp and msp1 genes. Both tandem repeat unit and nucleotide polymorphism in all three genes exhibited clear dimorphism between PPublication Open Access FlexiChip package: an universal microarray with a dedicated analysis software for high-thoughput SNPs detection linked to anti-malarial drug resistance.(2009-10-15) Steenkeste, Nicolas; Dillies, Marie-Agnès; Khim, Nimol; Sismeiro, Odile; Chy, Sophy; Lim, Pharath; Crameri, Andreas; Bouchier, Christiane; Mercereau-Puijalon, Odile; Beck, Hans-Peter; Mallika Imwong; มัลลิกา อิ่มวงศ์; Dondorp, Arjen M.; Socheat, Duong; Rogier, Christophe; Coppée, Jean- Yves; Ariey, Frédéric; Steenkeste, Nicolas; Mahidol University. Faculty of Tropical Medicine-nucleotide polymorphisms (SNP) associated with parasite resistance to anti-malarial drugs (ResMalChip) were adapted for a universal microarray FlexiChip format. To evaluate the overall sensitivity of the FlexiChip package (microarray + software), the results