{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,26]],"date-time":"2026-08-26T18:23:25Z","timestamp":1787768605212,"version":"build-2784847793"},"reference-count":21,"publisher":"Ovid Technologies (Wolters Kluwer Health)","issue":"1","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2015]]},"abstract":"\n Background:<\/jats:title>\n \n The emergence of antimalarial drug resistance malaria parasite is widespread in North eastern region of India. During January 2012-December 2013, we conducted active surveillance for detection of antifolate resistance-associated genetic polymorphisms in\n Plasmodium falciparum<\/jats:italic>\n malaria parasite from different malaria endemic areas of Assam.\n <\/jats:p>\n <\/jats:sec>\n \n Materials and Methods:<\/jats:title>\n \n A total of 281 field samples were collected from suspected malaria patients of which 106 malaria\n P. falciparum<\/jats:italic>\n positive cases were detected in microscopic slide examination. A nested PCR was done for amplification of a 648 bp portion of the\n dhfr<\/jats:italic>\n gene and 710 bp portion of the\n dhps<\/jats:italic>\n gene.\n <\/jats:p>\n <\/jats:sec>\n \n Results:<\/jats:title>\n \n Mutation analysis revealed existence of three different haplotypes of the\n P. falciparum dhfr<\/jats:italic>\n gene of which ANRNI was highly prevalent (90%). Triple mutant haplotypes AIRNI (N51I + C59R + S108N) of the\n dhfr<\/jats:italic>\n gene associated with pyrimethamine resistance were prevalent in Chirang district of Assam. Whereas,\n dhps<\/jats:italic>\n mutation study revealed that triple mutant haplotype AGEAA (S436A + A437G + K540E) associated with Sulphadoxine resistance was found among 26% of\n P. falciparum<\/jats:italic>\n field isolates. However,\n P. falciparum dhfr-dhps<\/jats:italic>\n two locus mutation analysis showed that there were a total of nine\n dhfr-dhps<\/jats:italic>\n genotypes.\n <\/jats:p>\n <\/jats:sec>\n \n Conclusion:<\/jats:title>\n \n It was noticed that 93.62% (88\/94) isolates had mutations in the sequences of both enzymes, which is an indication of prevalence of high grade of Sulphadoxine - pyrimethamine resistance in\n P. falciparum<\/jats:italic>\n malaria parasites in Assam.\n <\/jats:p>\n <\/jats:sec>","DOI":"10.4103\/0022-3859.147019","type":"journal-article","created":{"date-parts":[[2014,12,15]],"date-time":"2014-12-15T07:14:10Z","timestamp":1418627650000},"page":"9-14","source":"Crossref","is-referenced-by-count":10,"title":["Genetic polymorphisms associated with sulphadoxine-pyrimethamine drug resistance among Plasmodium falciparum field isolates in malaria endemic areas of Assam"],"prefix":"10.4103","volume":"61","author":[{"given":"J","family":"Sharma","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"P","family":"Dutta","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"SA","family":"Khan","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"M","family":"Soni","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"D","family":"Dey","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"J","family":"Mahanta","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"276","reference":[{"key":"R2-3-20240205","first-page":"123","article-title":"In-vivo resistance to chloroquine and sulpha pyrimethamine combination in P. falciparum in 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