title: Susceptibility studies of Malaysian Plasmodium falciparum clones to type II antifolate drugs after 3 years of continuous in vitro culture.
abstract: BACKGROUND
  Exposure of Plasmodium falciparum to increasing sublethal drug concentrations followed by drug treatment led to the development of many resistant parasites. Therefore, the susceptibility of these clones to the type II antifolate drugs, cycloguanil and pyrimethamine, before and after subculturing them in vitro for a period of 3 years, was studied.
  
  
  METHODS
  Thirty fresh clones were obtained from five different blood samples infected with P. falciparum isolates. They were tested for their susceptibility to the above drugs during the investigation period.
  
  
  RESULTS
  None of these clones changed their susceptibilities, before and after the investigation period.
  
  
  CONCLUSIONS
  This study gives further evidence that there is no alteration of the susceptibilities of the clones to the above drugs during the investigation period.
authors.affiliation: School of Pharmaceutical Sciences, University Science Malaysia, Minden, Penang. hhang@usm.my
authors.forename: Hooi Hoon
authors.initials: HH
authors.lastname: Ang
authors.forename: Hung Seong
authors.initials: HS
authors.lastname: Cheang
authors.forename: Joon Wah
authors.initials: JW
authors.lastname: Mak
mesh_terms: D000818:Animals; D000962:Antimalarials / Q000494:pharmacology*; D002999:Clone Cells; D004351:Drug Resistance; D005493:Folic Acid Antagonists / Q000494:pharmacology*; D066298:In Vitro Techniques; D008296:Malaysia; D010963:Plasmodium falciparum / Q000187:drug effects*; D002727:Proguanil; D011739:Pyrimethamine / Q000494:pharmacology*; D014227:Triazines / Q000494:pharmacology*
chemical_list: D000962:Antimalarials; D005493:Folic Acid Antagonists; D014227:Triazines; C026009:cycloguanil; D002727:Proguanil; D011739:Pyrimethamine