Antagonism of sulfadoxine and pyrimethamine antimalarial activity in vitro by p-aminobenzoic acid, p-aminobenzoylglutamic acid and folic acid.


:The activity of pyrimethamine and sulfadoxine against two strains of Plasmodium falciparum has been studied in vitro by a radioisotopic technique. Low level antagonism of pyrimethamine resulted from the inclusion of p-aminobenzoic acid, p-aminobenzoylglutamic acid or folic acid in the test medium. Sulfadoxine activity was antagonised slightly by p-aminobenzoic but not by p-aminobenzoylglutamic acid, and antagonised markedly by folic acid at concentrations above 4 X 10(-8) M. At 10(-7) M folic acid, a concentration lower than that of normal RPMI medium 1640, sulfadoxine activity was reduced 7000 to 9000-fold in comparison with controls. These results are of importance in terms of the utilisation of folates by P. falciparum, the susceptibility of the parasite to antifolate drugs and the in vitro determination of parasite susceptibility.


Mol Biochem Parasitol


Watkins WM,Sixsmith DG,Chulay JD,Spencer HC




Has Abstract


1985-01-01 00:00:00














  • A high level of mixed Trypanosoma brucei infections in tsetse flies detected by three hypervariable minisatellites.

    abstract::The issue of whether genetic exchange occurs at a significant frequency in natural populations of Trypanosoma brucei is controversial and one of the arguments against a high frequency has been the apparent lack of host infections with mixtures of trypanosome genotypes. Three minisatellite markers (MS42, CRAM, 292) wit...

    journal_title:Molecular and biochemical parasitology

    pub_type: 杂志文章


    authors: MacLeod A,Turner CM,Tait A

    更新日期:1999-08-20 00:00:00

  • Ecdysteroids in adults of the nematode, Dirofilaria immitis.

    abstract::Adult males and females of the dog heartworm, Dirofilaria immitis, were extracted separately and, following separation of the free and conjugated ecdysteroid fractions, the conjugates were hydrolysed enzymically. Both the ecdysteroids released by hydrolysis of the conjugates and the free hormones were further purified...

    journal_title:Molecular and biochemical parasitology

    pub_type: 杂志文章


    authors: Mendis AH,Rose ME,Rees HH,Goodwin TW

    更新日期:1983-11-01 00:00:00

  • Acidic phosphoproteins associated with the host erythrocyte membrane of erythrocytes infected with Plasmodium berghei and P. chabaudi.

    abstract::New phosphoproteins appear on the host erythrocyte membrane during Plasmodium berghei and P. chabaudi infection. Distinct proteins having similar properties and all distinguished by isoelectric points of less than 4.0 are identified. Associated with the erythrocyte membranes of P. berghei infected erythrocytes are two...

    journal_title:Molecular and biochemical parasitology

    pub_type: 杂志文章


    authors: Wiser MF,Leible MB,Plitt B

    更新日期:1988-01-01 00:00:00

  • Comparison of two methods for transformation of Plasmodium knowlesi: Direct schizont electroporation and spontaneous plasmid uptake from plasmid-loaded red blood cells.

    abstract::Human infections from Plasmodium knowlesi present challenges to malaria control in Southeast Asia. P. knowlesi also offers a model for other human malaria species including Plasmodium vivax. P. knowlesi parasites can be cultivated in the laboratory, and their transformation is standardly performed by direct electropor...

    journal_title:Molecular and biochemical parasitology

    pub_type: 杂志文章


    authors: Moraes Barros RR,Gibson TJ,Kite WA,Sá JM,Wellems TE

    更新日期:2017-12-01 00:00:00

  • Microarray based analysis of temperature and oxidative stress induced messenger RNA in Schistosoma mansoni.

    abstract::The body's defense against schistosome infection can take many forms. For example, upon developing acute schistosomiasis, patients often have fever coinciding with larval maturation, migration and early oviposition. As the infection becomes established, the parasite comes under oxidative stress generated by the host i...

    journal_title:Molecular and biochemical parasitology

    pub_type: 杂志文章


    authors: Aragon AD,Imani RA,Blackburn VR,Cunningham C

    更新日期:2008-12-01 00:00:00

  • Molecular epidemiology of giardiasis.

    abstract::Giardia duodenalis is a widespread parasite of mammalian species, including humans. Due to its invariant morphology, investigation on aspects such as host specificity and transmission patterns requires a direct genetic characterization of cysts/trophozoites from host samples. A number of molecular assays have been dev...

    journal_title:Molecular and biochemical parasitology

    pub_type: 杂志文章,评审


    authors: Cacciò SM,Ryan U

    更新日期:2008-08-01 00:00:00

  • Identification of a domain of Trypanosoma cruzi metacyclic trypomastigote surface molecule gp82 required for attachment and invasion of mammalian cells.

    abstract::Recombinant proteins and synthetic peptides representing various sequences of gp82, a surface glycoprotein of Trypanosoma cruzi metacyclic trypomastigotes implicated in mammalian cell invasion, were used in this study aiming at the identification of the domain(s) of this molecule required for interaction with target c...

    journal_title:Molecular and biochemical parasitology

    pub_type: 杂志文章


    authors: Santori FR,Dorta ML,Juliano L,Juliano MA,da Silveira JF,Ruiz RC,Yoshida N

    更新日期:1996-06-01 00:00:00

  • DNA microarrays for comparative genomics and analysis of gene expression in Trypanosoma cruzi.

    abstract::Trypanosoma cruzi presents high genetic diversity and parasite isolates show remarkable differences in biological parameters. In this study, we evaluated whether DNA microarrays containing CL Brener cDNAs can be used for comparative genomics and for the analysis of gene expression in T. cruzi. We constructed a prototy...

    journal_title:Molecular and biochemical parasitology

    pub_type: 杂志文章


    authors: Baptista CS,Vêncio RZ,Abdala S,Valadares MP,Martins C,de Bragança Pereira CA,Zingales B

    更新日期:2004-12-01 00:00:00

  • Plasmodium falciparum biosynthesizes sulfoglycosphingolipids.

    abstract::Sulfated glycosphingolipids are present on the surface of a variety of cells. They are active participants in adhesion processes in many systems and appear to be involved in the regulation of cell proliferation, differentiation and other developmental cellular events. However, the body of knowledge about synthesis, st...

    journal_title:Molecular and biochemical parasitology

    pub_type: 杂志文章


    authors: Landoni M,Duschak VG,Peres VJ,Nonami H,Erra-Balsells R,Katzin AM,Couto AS

    更新日期:2007-07-01 00:00:00

  • Demonstration of glycosomes (microbodies) in the Bodonid flagellate Trypanoplasma borelli (Protozoa, Kinetoplastida).

    abstract::Homogenates of Trypanoplasma borelli were subjected to subcellular fractionation by sequential differential and isopycnic centrifugation in sucrose. Glycerol-3-phosphate dehydrogenase and the glycolytic enzymes, glucosephosphate isomerase and triosephosphate isomerase, as well as the peroxisomal marker enzyme catalase...

    journal_title:Molecular and biochemical parasitology

    pub_type: 杂志文章


    authors: Opperdoes FR,Nohynkova E,Van Schaftingen E,Lambeir AM,Veenhuis M,Van Roy J

    更新日期:1988-08-01 00:00:00

  • Cysteine proteinase of Entamoeba histolytica. I. Partial purification and action on different enzymes.

    abstract::A method for a 50-60-fold purification of a cysteine proteinase from trophozoites of Entamoeba histolytica using 35-80% ammonium sulphate fractionation, gel chromatography on Sephadex G-75, and preparative isoelectric focusing is described. The enzyme was examined for its proteolytic potencies towards native enzyme su...

    journal_title:Molecular and biochemical parasitology

    pub_type: 杂志文章


    authors: Scholze H,Werries E

    更新日期:1986-01-01 00:00:00

  • Purification, characterization, and immunochemical studies of beta-N-acetyl-D-hexosaminidase from the parasitic nematode Trichinella spiralis.

    abstract::The exoglycosidase, beta-N-acetyl-D-hexosaminidase was purified 600-fold from the muscle-stage larvae (L1) of Trichinella spiralis. On sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), the purified enzyme-active fraction contained 4 polypeptides with apparent molecular weights of 100,000, 68,000, 5...

    journal_title:Molecular and biochemical parasitology

    pub_type: 杂志文章


    authors: Rhoads ML

    更新日期:1988-10-01 00:00:00

  • Amplification and sequencing of genomic DNA fragments encoding cysteine proteases from protozoan parasites.

    abstract::Cysteine protease gene fragments from three protozoan parasites Trypanosoma cruzi, Trypanosoma brucei, and Entamoeba histolytica were amplified by the polymerase chain reaction (PCR) from genomic DNA using degenerate oligonucleotide primers. The primers used for the amplification were designed based upon amino acid se...

    journal_title:Molecular and biochemical parasitology

    pub_type: 杂志文章


    authors: Eakin AE,Bouvier J,Sakanari JA,Craik CS,McKerrow JH

    更新日期:1990-02-01 00:00:00

  • Gender biased differential alternative splicing patterns of the transcriptional cofactor CA150 gene in Schistosoma mansoni.

    abstract::The complex molecular systems involved in the process of sex-differentiation and fertility in Schistosoma mansoni have not yet been completely described. Using a 4608-element cDNA microarray, we have now determined 90 and 139 genes with significantly (q-value

    journal_title:Molecular and biochemical parasitology

    pub_type: 杂志文章


    authors: DeMarco R,Oliveira KC,Venancio TM,Verjovski-Almeida S

    更新日期:2006-12-01 00:00:00

  • Antibodies raised against receptor-binding domain of Plasmodium knowlesi Duffy binding protein inhibit erythrocyte invasion.

    abstract::Erythrocyte invasion by malaria parasites requires specific receptor-ligand interactions. Plasmodium vivax and Plasmodium knowlesi are completely dependent on binding the Duffy blood group antigen to invade human erythrocytes. P. knowlesi invades rhesus erythrocytes by multiple pathways using the Duffy antigen as well...

    journal_title:Molecular and biochemical parasitology

    pub_type: 杂志文章


    authors: Singh AP,Puri SK,Chitnis CE

    更新日期:2002-04-30 00:00:00

  • Identification of Eimeria bovis merozoite cDNAs using differential mRNA display.

    abstract::Differences in gene expression between Eimeria bovis sporozoites and first-generation merozoites were analyzed using the technique of differential mRNA display. Approx. 5% of the sequences detected in first-generation merozoites appear to be unique relative to sporozoites. Several of the bands corresponding to merozoi...

    journal_title:Molecular and biochemical parasitology

    pub_type: 杂志文章


    authors: Abrahamsen MS,Johnson RR,Hathaway M,White MW

    更新日期:1995-05-01 00:00:00

  • The reversible effect of glucose on the energy metabolism of Schistosoma mansoni cercariae and schistosomula.

    abstract::This study on isolated cercarial bodies demonstrates that the biological transformation from cercaria to schistosomulum and the biochemical transition from an aerobic to an anaerobic energy metabolism are separate processes, which are not necessarily linked. The metabolic transition depends on the external glucose con...

    journal_title:Molecular and biochemical parasitology

    pub_type: 杂志文章


    authors: Horemans AM,Tielens AG,van den Bergh SG

    更新日期:1992-03-01 00:00:00

  • Substrate specificities of 5'-deoxy-5'-methylthioadenosine phosphorylase from Trypanosoma brucei brucei and mammalian cells.

    abstract::The separation by chromatofocusing of two distinct purine nucleoside cleaving activities from crude extracts of Trypanosoma brucei brucei is described. One catalyzes the reversible phosphorolysis of 5'-deoxy-5'-methylthioadenosine (MeSAdo) and adenosine (Ado) and was designated an MeSAdo/Ado phosphorylase, while the o...

    journal_title:Molecular and biochemical parasitology

    pub_type: 杂志文章


    authors: Ghoda LY,Savarese TM,Northup CH,Parks RE Jr,Garofalo J,Katz L,Ellenbogen BB,Bacchi CJ

    更新日期:1988-01-15 00:00:00

  • Excretory/secretory products from in vitro-cultured Echinococcus granulosus protoscoleces.

    abstract::Cystic hydatid disease (CHD) is caused by infection with Echinococcus granulosus metacestodes and affects humans and livestock. Proteins secreted or excreted by protoscoleces, pre-adult worms found in the metacestode, are thought to play fundamental roles in the host-parasite relationship. In this work, we performed a...

    journal_title:Molecular and biochemical parasitology

    pub_type: 杂志文章


    authors: Virginio VG,Monteiro KM,Drumond F,de Carvalho MO,Vargas DM,Zaha A,Ferreira HB

    更新日期:2012-05-01 00:00:00

  • Presence of contaminating mitochondrial DNA from host reticulocytes in experimental infections of Plasmodium berghei.

    abstract::Superposition of two unrelated processes, namely terminal reticulocyte differentiation and synchronous plasmodial development, takes place in experimental infections of Plasmodium berghei. The first process is shown to be responsible for the appearance of some discrete restriction bands of host origin when DNA is extr...

    journal_title:Molecular and biochemical parasitology

    pub_type: 杂志文章


    authors: Pace T,Ponzi M,Dore E,Scotti R,Mons B

    更新日期:1989-11-01 00:00:00

  • Liver collagen turnover in hamsters during infection by the human liver fluke, Opisthorchis viverrini.

    abstract::Hamsters infected with Opisthorchis viverrini, a liver fluke of man, showed an increased deposition of collagen in their livers. However, increased collagen breakdown as well as its synthesis were observed in the infected livers. Thus, stimulated synthesis might be the main factor responsible for the net increase in c...

    journal_title:Molecular and biochemical parasitology

    pub_type: 杂志文章


    authors: Hutadilok N,Ruenwongsa P

    更新日期:1983-05-01 00:00:00

  • Glycogen metabolism in Schistosoma mansoni worms after their isolation from the host.

    abstract::Adult Schistosoma mansoni worms rapidly degrade their endogenous glycogen stores immediately after isolation from the host. In NCTC 109 or in a diphasic culture medium the glycogen levels slowly recovered again after the initial decrease. The rapid degradation of glycogen could be prevented, even in a simple salt medi...

    journal_title:Molecular and biochemical parasitology

    pub_type: 杂志文章


    authors: Tielens AG,van den Bergh SG

    更新日期:1987-07-01 00:00:00

  • The T687G SNP in a P-glycoprotein gene of Fasciola hepatica is not associated with resistance to triclabendazole in two resistant Australian populations.

    abstract::Triclabendazole (TCBZ) is widely used for control of Fasciola hepatica (liver fluke) in animals and humans and resistance to this drug is now widespread. However, the mechanism of resistance to TCBZ is not known. A T687G single nucleotide polymorphism (SNP) in a P-glycoprotein gene was proposed as a molecular marker f...

    journal_title:Molecular and biochemical parasitology

    pub_type: 杂志文章


    authors: Elliott TP,Spithill TW

    更新日期:2014-11-01 00:00:00

  • Substrate specificity of recombinant cysteine proteinase, CPB, of Leishmania mexicana.

    abstract::The primary S(1) subsite specificity of a recombinant cysteine proteinase, CPB2.8 Delta CTE, of Leishmania mexicana was investigated in a systematic way using a series of peptides derived from Abz-KLRFSKQ-EDDnp in which Arg was substituted by all natural amino acids (where Abz is ortho-amino-benzoyl and EDDnp is N-[2,...

    journal_title:Molecular and biochemical parasitology

    pub_type: 杂志文章


    authors: Alves LC,Judice WA,St Hilaire PM,Meldal M,Sanderson SJ,Mottram JC,Coombs GH,Juliano L,Juliano MA

    更新日期:2001-08-01 00:00:00

  • Transient transfection and expression of foreign and endogenous genes in the intracellular stages of Trypanosoma cruzi.

    abstract::The capacity for rapid localization of epitope-tagged or fluorescent fusion proteins in cells is an important tool for biological discovery and functional analysis. For Trypanosoma cruzi, the protozoan parasite that causes human Chagas disease, visualization of ectopically-expressed proteins in the clinically-relevant...

    journal_title:Molecular and biochemical parasitology

    pub_type: 杂志文章


    authors: Padmanabhan PK,Polidoro RB,Barteneva NS,Gazzinelli RT,Burleigh BA

    更新日期:2014-12-01 00:00:00

  • Identification of peripheral membrane proteins associated with the tubo-vesicular network of Plasmodium falciparum infected erythrocytes.

    abstract::During intracellular development of the malarial parasite numerous membranous vesicles appear in the infected erythrocyte cytoplasm between the parasitophorous vacuolar membrane (PVM) and the erythrocyte plasma membrane. In this study we describe the characterization of a monoclonal antibody which recognizes two major...

    journal_title:Molecular and biochemical parasitology

    pub_type: 杂志文章


    authors: Martinez SL,Clavijo CA,Winograd E

    更新日期:1998-03-15 00:00:00

  • Transgenic Plasmodium berghei sporozoites expressing beta-galactosidase for quantification of sporozoite transmission.

    abstract::Malaria transmission occurs during a blood-meal of an infected Anopheles mosquito. Visualization and quantification of sporozoites along the journey from the mosquito midgut, where they develop, to the vertebrate liver, their final target organ, is important for understanding many aspects of sporozoite biology. Here w...

    journal_title:Molecular and biochemical parasitology

    pub_type: 杂志文章


    authors: Engelmann S,Sinnis P,Matuschewski K

    更新日期:2006-03-01 00:00:00

  • Organization, sequence and stage-specific expression of the phosphoglycerate kinase genes of Leishmania mexicana mexicana.

    abstract::In Leishmania mexicana two genes were detected coding for different isoforms of the glycolytic enzyme phosphoglycerate kinase. This situation contrasts with that observed in other Trypanosomatidae (Trypanosoma brucei, Trypanosoma congolense, Crithidia fasciculata) analyzed previously, which all contain three different...

    journal_title:Molecular and biochemical parasitology

    pub_type: 杂志文章


    authors: Adjé CA,Opperdoes FR,Michels PA

    更新日期:1997-12-01 00:00:00

  • Mediation of Trypanosoma cruzi invasion by heparan sulfate receptors on host cells and penetrin counter-receptors on the trypanosomes.

    abstract::Trypanosoma cruzi attaches and invades a large variety of mammalian cells by receptor-mediated interactions, one of them involving the binding of parasite trans-sialidase to host sialyl receptors. Three proteoglycan-deficient mutants of Chinese hamster ovary (CHO) cells were used to probe the role of host heparin and ...

    journal_title:Molecular and biochemical parasitology

    pub_type: 杂志文章


    authors: Herrera EM,Ming M,Ortega-Barria E,Pereira ME

    更新日期:1994-05-01 00:00:00

  • Transient expression of luciferase in Entamoeba histolytica driven by the ferredoxin gene 5' and 3' regions.

    abstract::We have successfully transfected Entamoeba histolytica trophozoites with constructs containing ferredoxin sequences fused to the reporter gene luciferase. We have determined the conditions and parameters necessary to maximise transient luciferase expression in our system. Our optimal construct gave values of 268 x 10(...

    journal_title:Molecular and biochemical parasitology

    pub_type: 杂志文章


    authors: Gilchrist CA,Streets HL,Ackers JP,Hall R

    更新日期:1995-10-01 00:00:00