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Publication Metadata only Quality assurance of drugs used in clinical trials: Proposal for adapting guidelines(2015-02-25) Paul N. Newton; David Schellenberg; Elizabeth A. Ashley; Raffaella Ravinetto; Michael D. Green; Feiko O. Ter Kuile; Patricia Tabernero; Nicholas J. White; Philippe J. Guerin; Mahosot Hospital; London School of Hygiene & Tropical Medicine; Mahidol University; Prins Leopold Instituut voor Tropische Geneeskunde; Centers for Disease Control and Prevention; Liverpool School of Tropical Medicine; University of Oxford; Churchill HospitalPublication Metadata only Low effective dispersal of asexual genotypes in heterogeneous landscapes by the endemic pathogen penicillium marneffei(2005-12-01) Matthew C. Fisher; William P. Hanage; Sybren De Hoog; Elizabeth Johnson; Michael D. Smith; Nicholas J. White; Nongnuch Vanittanakom; Imperial College London; CBS Fungal Biodiversity Center CBS - KNAW; Health Protection Agency; Taunton and Somerset NHS Trust; Mahidol University; Chiang Mai Universityaerially dispersed spores. One mechanism that might tend to drive such endemicity in the face of aerial dispersal is the evolution of niche-adapted genotypes when sexual reproduction is rare. Dispersal of such asexual physiological "species..." will be restricted when natural habitats are heterogeneous, as a consequence of reduced adaptive variation. Using the HIV-associated endemic fungus Penicillium marneffei as our model, we measured the distribution of genetic variation over a variety of spatial scalesPublication Metadata only Population parameters underlying an ongoing soft sweep in southeast asian malaria parasites(2017-01-01) Timothy J.C. Anderson; Shalini Nair; Marina McDew-White; Ian H. Cheeseman; Standwell Nkhoma; Fatma Bilgic; Rose McGready; Elizabeth Ashley; Aung Pyae Phyo; Nicholas J. White; Francois Nosten; Texas Biomedical Research Institute; Mahidol University; Nuffield Department of Clinical Medicine% by 2014, consistent with a selection coefficient of ∼0.079. ART-R allele diversity rose until 2012 and then dropped as one allele (C580Y) spread to high frequency. The frequency with which adaptive alleles arise is determined by the rate of mutation... previously underestimated the capacity for adaptive evolution in Plasmodium. Our central conclusions are that retrospective studies may underestimate the complexity of selective events and the Ne relevant for adaptation for malaria is considerably higher thanPublication Metadata only Geographical distribution of selected and putatively neutral SNPs in Southeast Asian malaria parasites(2005-12-01) Tim J.C. Anderson; Shalini Nair; Dan Sudimack; Jeff T. Williams; Mayfong Mayxay; Paul N. Newton; Jean Paul Guthmann; Frank M. Smithuis; Tran Tinh Hien; Ingrid V.F. Van Den Broek; Nicholas J. White; François Nosten; Texas Biomedical Research Institute; National University of Laos; Mahosot Hospital; Churchill Hospital; Medecins Sans Frontieres; Artsen Zonder Grenzen; UCL; Médecins Sans Frontières; Mahidol University; Shoklo Malaria Research UnitLoci targeted by directional selection are expected to show elevated geographical population structure relative to neutral loci, and a flurry of recent papers have used this rationale to search for genome regions involved in adaptation. Studies... of functional mutations that are known to be under selection are particularly useful for assessing the utility of this approach. Antimalarial drug treatment regimes vary considerably between countries in Southeast Asia selecting for local adaptation at parasitePublication Metadata only Artemisinin resistance without pfkelch13 mutations in Plasmodium falciparum isolates from Cambodia(2017-05-12) Angana Mukherjee; Selina Bopp; Pamela Magistrado; Wesley Wong; Rachel Daniels; Allison Demas; Stephen Schaffner; Chanaki Amaratunga; Pharath Lim; Mehul Dhorda; Olivo Miotto; Charles Woodrow; Elizabeth A. Ashley; Arjen M. Dondorp; Nicholas J. White; Dyann Wirth; Rick Fairhurst; Sarah K. Volkman; Harvard School of Public Health; Broad Institute; National Institute of Allergy and Infectious Diseases; Worldwide Antimalarial Resistance Network; Nuffield Department of Clinical Medicine; Mahidol University; Wellcome Trust Centre for Human Genetics; Wellcome Trust Sanger Institute; Academic Medical Centre, University of Amsterdam; Simmons Collegestudy sites in Cambodia, culture-adapted, and genotyped for pfkelch13 and other mutations including pfmdr1 copy number; and the RSA0-3h survival rates and response to antimalarial drugs in vitro were measured for 36 of these isolates. Results: Among... lack pfkelch13 mutations, and one isolate showed evidence for piperaquine resistance. Conclusions: This study of 68 culture-adapted Plasmodium falciparum clinical isolates from Cambodia with known clearance values, associated the D584V PfKelch13Publication Metadata only Biological relevance of colony morphology and phenotypic switching by Burkholderia pseudomallei(2007-02-01) Narisara Chantratita; Vanaporn Wuthiekanun; Khaemaporn Boonbumrung; Rachaneeporn Tiyawisutsri; Mongkol Vesaratchavest; Direk Limmathurotsakul; Wirongrong Chierakul; Surasakdi Wongratanacheewin; Sasithorn Pukritiyakamee; Nicholas J. White; Nicholas P J Day; Sharon J. Peacock; Mahidol University; Chulalongkorn University; Khon Kaen University; Nuffield Department of Clinical MedicineMelioidosis is a notoriously protracted illness and is difficult to cure. We hypothesize that the causative organism, Burkholderia pseudomallei, undergoes a process of adaptation involving altered expression of surface determinants which facilitates... morphotypes occurred in a mouse model, where type II appeared to become adapted for persistence in a low-virulence state. Isogenic type II demonstrated a significant increase in intracellular replication fitness compared with parental type I after uptakePublication Metadata only Why Do Some Primate Malarias Relapse?(2016-12-01) Nicholas J. White; Mahidol University; Churchill Hospitalnecessary adaptation as early hominins moved to colder areas with shorter mosquito breeding seasons. Genetic diversity was maintained through heterologous hypnozoite activation.Publication Metadata only The duration of Plasmodium falciparum infections(2014-01-01) Elizabeth A. Ashley; Nicholas J. White; Mahidol University; Nuffield Department of Clinical Medicine© 2014 Ashley and White. Plasmodium vivax and Plasmodium ovale are often considered the malaria parasites best adapted to long-term survival in the human host because of their latent exo-erythrocytic forms. The prevailing opinion until the middlePublication Metadata only Plasmodium falciparum genome-wide scans for positive selection, recombination hot spots and resistance to antimalarial drugs(2010-03-01) Jianbing Mu; Rachel A. Myers; Hongying Jiang; Shengfa Liu; Stacy Ricklefs; Michael Waisberg; Kesinee Chotivanich; Polrat Wilairatana; Srivicha Krudsood; Nicholas J. White; Rachanee Udomsangpetch; Liwang Cui; May Ho; Fengzhen Ou; Haibo Li; Jianping Song; Guoqiao Li; Xinhua Wang; Suon Seila; Sreng Sokunthea; Duong Socheat; Daniel E. Sturdevant; Stephen F. Porcella; Rick M. Fairhurst; Thomas E. Wellems; Philip Awadalla; Xin Zhuan Su; National Institute of Allergy and Infectious Diseases; University of Montreal; North Carolina State University; Xiamen University; National Institutes of Health, Bethesda; Mahidol University; Pennsylvania State University; University of Calgary; Research Center for Qinghao; Guangzhou University of Traditional Chinese Medicine; National Center for Parasitology, Entomology and Malaria Controlassociation studies (GWAS) of parasite traits have been hampered by the lack of high-throughput genotyping methods, inadequate knowledge of parasite population history and time-consuming adaptations of parasites to in vitro culture. Here we report the first... Plasmodium GWAS, which included 189 culture-adapted P. falciparum parasites genotyped using a custom-built Affymetrix molecular inversion probe 3K malaria panel array with a coverage of 1 SNP per 7 kb. Population structure, variation in recombination ratePublication Metadata only How can we do pharmacokinetic studies in the tropics?(2001-01-01) Julie A. Simpson; Leon Aarons; Nicholas J. White; University of Aberdeen; University of Manchester; Mahidol University; Nuffield Department of Clinical Medicine; Foresterhill Health Centre'the population approach'. Modern assay techniques can often be adapted to small blood volumes allowing finger prick blood samples to be taken. One of the major aims of the population approach is to distinguish and characterize patient and disease contributors
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