Publications

the antimalarial activity of n-benzyloxydihydrotriazines. i. the activity of clociguanil (brl 50216) against rodent malaria, and studies on its mode of action.		1980	7006531
the antimalarial activity of n-benzyloxydihydrotriazines. ii. the development of resistance to clociguanil (brl 50216) and cycloguanil by p. berghei.		1980	6450572
[antimalarial activities of 25 derivatives of artemisinine against chloroquine-resistant plasmodium berghei (author's transl)].		1980	6461175
[immunosuppressive response to antidiphtheria vaccine in animals infected by plasmodium berghei yoëlii].		1980	6927588
[immunosuppressive response to antitetanus vaccine in mice infected with plasmodium berghei yoëlii].		1980	6927589
[effect of adjuvants on the immunosuppressive effect of the parasitic action of plasmodium berghei yoëlii].		1980	6927590
dihydrofolate reductase: thymidylate synthase, a bifunctional polypeptide from crithidia fasciculata.	the molecular weight of dihydrofolate reductase (5,6,7,8-tetrahydrofolate:nadp+ oxidoreductase, ec 1.5.1.3) from protozoa has been reported to be 5- to 10-fold larger than the isofunctional enzyme of most other organisms studied, based on gel filtration. this enzyme from the protozoal flagellate crithidia fasciculata has been purified to homogeneity and found to be a bifunctional protein with thymidylate synthase (5,10-methylene tetrahydrofolate:dump c-methyltransferase, ec 2.1.1.45) activity. t ...	1980	6934511
synthesis of potential inhibitors of hypoxanthine-guaine phosphoribosyltransferase for testing as antiprotozoal agents. 2. 1-substituted hypoxanthines.	evidence incicating that effective in vivo inhibition of hypoxanthine-guanine phosphoribosyltransferase (hgprt, ec 2.4.2.8) should produce antiprotozoal activity without significant toxic effects on mammalian hosts prompted syntheses of 1-substituted hypoxanthines bearing functionalized side chains whose groupings might interact with appropriate groupings of hgprt to form covalent bonds or strong hydrophobic bonds. 3-(fluorosulfonyl)benzoyl, 4-(fluorosulfonyl)benzoyl, 4-chlorobenzoyl, and bromac ...	1980	7420359
pregnancy associated recrudescence in murine malaria (plasmodium berghei).	depending on the strain, a variable proportion of mice solidly immune to the rodent malaria parasite plasmodium berghei developed a recrudescence during pregnancy that was either transient or lethal. recrudescence was not observed in all mice, and the rate was lower in gravida ii as compared to gravida i mice. on the other hand a proportion of the mice that did not develop recrudescence exhibited a pregnancy associated clearance of persisting parasites in immune mice (premunition-sterile immunit ...	1980	7015633
role of spleen in morbidity and mortality of plasmodium berghei infection in mice.	splenectomy has a strain-specific effect on plasmodium berghei infection in mice. mean survival time either was unchanged or increased to three times the value observed in intact controls. a delay of early mortality, which was otherwise observed in the second week of infection, was a general feature of susceptible strains. delayed mortality was also observed when splenectomy was performed shortly before expected mortality. ineffectiveness of splenectomy as to increased survival time was independ ...	1980	7014442
the effect of cryopreservation on gametocytogenesis of plasmodium berghei berghei: a preliminary report.		1980	7020321
towards tumor therapy with interferons, part ii. interferons: in vivo effects.		1980	6155160
effects of photosensitive chemicals on malaria parasite cells.		1980	6155821
the dual role of macrophages in the sporozoite-induced malaria infection. a hypothesis.		1980	6156920
the human materno-foetal relationship in malaria: i. identification of pigment and parasites in the placenta.	to facilitate investigations of the consequences of malarial infection during human pregnancy, several methods for the recognition of pigment and parasites in the placenta were evaluated. pigment was visualized in infected blood smears and placental tissue using both white light and modified fluorescence microscopy. however, the characteristic pigment dots observed with fluorescent light were also apparent in unstained cryostat and deparaffinized placental sections, and following reaction with i ...	1980	6159702
plasmodium yoelii and plasmodium berghei: isolation of infected erythrocytes from blood by colloidal silica gradient centrifugation.		1980	6248355
studies on the resistance to single and combined antimalarials in the plasmodium berghei mouse model.		1980	6106358
antimalarial aminoalcohol alternatives to mefloquine.		1980	6106359
plasmodium berghei: premunition, sterile immunity, and loss of immunity in mice.		1980	6985593
plasmodium berghei: t cell-dependent autoimmunity.		1980	6985594
hybridoma produces protective antibodies directed against the sporozoite stage of malaria parasite.	hybrid cells secreting antibodies against sporozoites of plasmodium berghei were obtained by fusion of plasmacytoma cells with immune murine spleen cells. the monoclonal antibodies bound to a protein with an apparent molecular weight of 44,000 (pb44), which envelopes the surface membrane of sporozoites. incubation of sporozoites in vitro with antibodies to pb44 abolished their infectivity.	1980	6985745
resolution of acute malaria (plasmodium berghei in the rat): reversibility and spleen dependence.	six-week-old rats infected with plasmodium berghei developed a peak parasitemia of 55.2 +/- 3.1% by day 15 of infection, followed by spontaneous resolution of the infection during a process referred to as crisis. crisis was accompanied by the appearance in circulation of infected erythrocytes in which the parasites appeared abnormal ("crisis forms"). rats splenectomized at different times during the crisis period experienced a sudden increase in parasitemia, with a marked decrease in the number ...	1980	6986095
host defenses in murine malaria: immunological characteristics of a protracted state of immunity to plasmodium yoelii.	random-bred icr mice recovered from infection with avirulent plasmodium yoelii were challenged at various later times with virulent p. yoelii or with another species of plasmodium, p. berghei, to characterize the immunological nature of the long-term state of immunity generated in response to the avirulent infection. it was found that recovered mice resisted lethal challenge with virulent p. yoelii through at least 416 days after primary infection. however, the quality of this immunity changed a ...	1980	6987179
effect of selenium and dimethyl dioctadecyl ammonium bromide on the vaccine-induced immunity of swiss-webster mice against malaria (plasmodium berghei).	the results of the study described in this paper demonstrate that selenium, administered in drinking water, potentiates the protective effect of a killed plasmodium berghei vaccine for swiss-webster mice. we also report that a vaccine consisting of p. berghei antigen combined with the adjuvant dimethyl dioctadecyl ammonium bromide conferred a significantly high level of protective immunity. an additive effect was shown in that the greatest degree of protection was afforded to the group of mice m ...	1980	6987181
a solid-phase antibody binding-inhibition test, for the assay of plasmodium berghei antigen and antibodies, using radioiodinated protein a.	sonicated red blood cells (rbc) of rats infected with plasmodium berghei (pb) were used to coat plastic tubes with pb antigens. the antigen-coated tubes were employed to detect pb antigens and antibodies, with high efficiency. anti-pb antibodies were estimated by treating the tubes with rabbit or rat anti-pb sera and assaying the bound ig with radiolabeled staphylococcus pra. pb antigens were detected by their capacity to inhibit the binding of the anti-pb antibodies. using a rabbit-pb serum, so ...	1980	6987313
changes in the membrane microviscosity of mouse red blood cells infected with plasmodium berghei detected using n-(9-anthroyloxy) fatty acid fluorescent probes.	a set of n-(9-anthroyloxy) fatty acids (n = 2, 6, 9, 12, 16) have been used as fluorescent probes to examine the lipid environment at different depths in the outer membrane of normal mouse erythrocytes and red blood cells from plasmodium berghei-infected blood. fluorescent polarization experiments with normal mouse erythrocytes have demonstrated a typical gradient in microviscosity from the surface to the centre of the bilayer as a consequence of the motional properties of the c-atoms of the pho ...	1980	6988766
[structure dependance of antiplasmodic activity of 3-[n-(4-amidosulfonylphenyl)aminomethyl]-quinoline (author's transl)].		1980	6989342
the inhibitory effect of a drug combination on the development of mefloquine resistance in plasmodium berghei.		1980	6990883
ferriprotoporphyrin ix fulfills the criteria for identification as the chloroquine receptor of malaria parasites.		1980	6990976
isolation of a soluble component of plasmodium berghei which induces immunity in rats.	soluble material was obtained from sonically freed plasmodiae by three procedures. two procedures, cryo-impacting and freeze-thawing, were evaluated for their ability to disrupt the parasites and release soluble material. the soluble materials obtained by these procedures were compared to materials washed from the surfaces of sonically freed parasites. between 35 and 40% of the total parasite protein was solubilized by freeze-thawing or cryo-impacting. one cycle of freeze-thawing released nearly ...	1980	6991439
monovalent fragments (fab) of monoclonal antibodies to a sporozoite surface antigen (pb44) protect mice against malarial infection.	monoclonal antibodies (ig1, k) directed against a surface component of plasmodium berghei sporozoites (pb-44) confer complete protection to mice against a lethal inoculum of parasites. the degree of protection is a function of the number of parasites used in the challenge and of the antibody concentration in serum. passive transfer of 10 micrograms of antibody per mouse abolished or profoundly diminished the infectivity of 10(3) sporozoites, but much higher amounts of antibody were required for ...	1980	6991628
synthesis of potential inhibitors of hypoxanthine-guanine phosphoribosyltransferase for testing as antiprotozoal agents. 1. 7-substituted 6-oxopurines.	biological evidence indicates that the enzyme hypoxanthine-guanine phosphoribosyltransferase (ec 2.4.2.8) is vital for cell proliferation in malarial parasites but nonessential for mammalian cells. 7-substituted guanines and hypoxanthines in which the 7 substituent bears functional or hydrophobic groups were prepared with the aim of finding a suitably constituted compound whose resemblance to the normal substrate allows it to compete for the reversible purine binding site of hgrptase while allow ...	1980	6991691
the diagnosis of malaria infection using a solid-phase radioimmunoassay for the detection of malaria antigens. application to the detection of plasmodium berghei infection in mice.	a method has been devised to show that malaria parasites can be detected serologically in infected blood with a high degree of sensitivity. using a murine malaria model, parasites were demonstrated in a solid-phase radio-immunoassay which measured antibody-binding inhibition. lysed red blood cells (r.b.c.) were incubated with labelled specific antibody and were then reacted in antigen-coated tubes. the degree of inhibition of antibody binding in the tubes correlated with the level of parasitaemi ...	1980	6992060
immunization against rodent malaria with cryopreserved irradiated sporozoites of plasmodium berghei.	the preparation and storage of plasmodium berghei sporozoites for immunization purposes is described. the sporozoites were harvested from the salivary glands of infected mosquitoes, and maintained in cold tissue culture medium m199 with or without mouse serum. they were irradiated and frozen either at -75 degrees c or in liquid nitrogen. after various periods sporozoites were thawed and injected into a/j mice. at the end of the immunization period the animals were challenged with infective sporo ...	1980	6992606
purine base and nucleoside uptake in plasmodium berghei and host erythrocytes.	the absorption of 3h-labeled adenine, adenosine, hypoxanthine, and 14c-labeled inosine by normal rat erythrocytes, plasmodium bergheri-infected erythrocytes and saponin released "free parasites" was measured. the uptake of these labeled substrates by normal rat erythrocytes occurs both by diffusion and mediated transport systems. similar absorptive mechanisms for these substrates also were observed for both plasmodium berghei-infected erythrocytes and "free parasites." data from inhibition studi ...	1980	6993639
immunization of rats against malaria: a new model.		1980	6993642
structure-activity analyzed by pattern recognition: the asymmetric case.	in classification studies in which pattern-recognition methods are used to distinguish active compounds from inactive ones, a type of data structure which we call "asymmetric" can be observed. this type of data structure can be quite common and its occurrence can have a profound effect on the classification analysis outcome. the origin of asymmetric data structure and a strategy or obtaining meaningful classification results when it is observed are discussed and illustrated with an example of ac ...	1980	6993681
[morphological incidences of the agglutination of the erythrocytes of healthy or infested (plasmodium berghei) mouse by various experimental immune sera (author's transl)].		1980	6994569
the chemotherapy of rodent malaria, xxxii. the influence of p-aminobenzoic acid on the transmission of plasmodium yoelii and p. berghei by anopheles stephensi.	more oocysts of plasmodium yoelii developed in anopheles stephensi if the mosquitoes received a supplement of p-aminobenzoic acid (paba) in their diet prior to their taking an infective blood meal, than in unsupplemented control insects. the optimum concentration was 0.05% paba in 10% sucrose. this effect was not observed if the blood meal was taken prior to feeding with paba. similarly, paba administered to gametocyte-carrying mice increased the numbers of oocysts developing in mosquitoes fed o ...	1980	6994664
liver xanthine oxidase increase in mice in three patholgoical models. a possible defence mechanism.		1980	6994748
xanthine oxidase increase in polymorphonuclear leucocytes and macrophages in mice in three pathological situations.		1980	6994749
depressed malarial immunity in pregnant mice.	a proportion of mice solidly immune to the rodent malaria parasite plasmodium berghei exhibited a pregnancy-associated depressed immunity with a transient or even lethal recrudescence.	1980	6995314
host responses induced in mice by a radiation-attenuated plasmodium berghei (nk65) malaria parasite.		1980	6995369
distribution of chloroquine in normal, pronase-treated and malaria-infected red cells.		1980	6995763
10-hydroxy-3,4-dihydroacridine-1,9(2h,10h)-diones, a new group of malaricidal and coccidiostatic compounds.	2-nitrobenzaldehydes and 1,3-cyclohexanediones condense in a mixture of hydrochloric acid and glacial acetic acid to 10-hydroxy-3,4-dihydroacridine-1,9(2h,10h)-diones. many compounds of this group reveal a pronounced coccidiostatic and malaricidal effect in vivo even against drug-resistant malaria parasites. synthesis and chemotherapeutic results as well as structure-activity relationships are described.	1980	6998488
enhanced fusion capacity of malaria (plasmodium berghei)-infected mouse red cells.	the capacity of normal and malaria-infected mouse red cells to undergo fusion was investigated by phase contrast microscopy. the fusion of mouse red cells induced by 50% w/w poly(ethylene glycol)-6000 in the presence of ca+2 is enhanced by p. berghei infection. cells carrying parasites in the ring form stage and early trophozoite stage show slightly higher fusion induced by dimethyl sulphoxide and ca+2 than those carrying parasites in trophozoite and schizont stages.	1980	6998573
cold isohaemagglutinins in plasmodium berghei-infected rats reacting with parasitized reticulocytes.	significant levels of cold igm and igg isohaemagglutinins were detected in the serum of rats infected with plasmodium berghei ksp 11. peak titres occurred 15 days after initial infection at the time when the parasitaemia was dropping rapidly, or 7 days after a second challenge infection. infected reticulocytes were much more sensitive to agglutination than uninfected cells, but absorption experiments demonstrated isoantigenicity in the determinants involved. this result indicated that the presen ...	1980	6998593
binding of antimalarial drugs to hemozoin from plasmodium berghei.	chloroquine, quinacrine and mefloquine bind to plasmodium berghei hemozoin, hemin, hemi, protoporphyrin ix and protease digested methemoglobin. this binding may be the basis for drug accumulation and action in the parasite.	1980	6998717
cellular changes in the bone marrow of plasmodium berghei-infected mice. ii. blast transformation and phagocytosis.		1980	7000373
endotoxin in human and murine malaria.		1980	7001682
culture of the liver stages (exoerythrocytic schizonts) of rodent malaria parasites from sporozoites in vitro.		1980	7001683
biosynthesis of uridine monophosphate in plasmodium berghei.	high activities of the enzymes orotate phosphoribosyltransferase and orotidylate decarboxylase, that convert orotic acid to uridine monophosphate, have been demonstrated in crude supernatants obtained from lysed plasmodium berghei. the enzymes are inhibited in vitro by 5-azaorotate, 5-azauracil and 6-azauracil. of these, 5-azaorotate was the most effective and could serve as the prototype of a potential antimalarial.	1980	7002072
induction of cell-mediated responses against malarial erythrocytic stage through chemically pre-treated burkitt lymphoma tumour cells.		1980	7002309
molecular complexes of quinoline antimalarials with iron-porphyrin components of protease-digested methemoglobin.	chloroquine, quinine, mefloquine and quinacrine have been found by difference spectroscopy to interact with hemozoin from plasmodium berghei, trypsin and pronase-digested methemoglobin, hemin, heme, protoporphyrin ix and hematoporphyrin. these drugs also compete with one another in their binding to hemin. it is proposed that the iron-porphyrin moiety of digested hemoglobin is a common binding site for the accumulation of the schizontocidal drugs in the autophagosomes of the malarial parasite.	1980	7002334
changes in lysosomal enzymes of peritoneal exudate cells in albino rats and mastomys natalensis during plasmodium berghei infection.	activities of certain lysosomal enzymes of peritoneal exudate cells were followed during plasmodium berghei infection in two experimental hosts. in albino rats, where sterile immunity against the infection develops, levels of beta-d-glucuroniodase and acid phosphatase activities were increased several times the normal values. on the other hand, in mastomys natalensis, which succumbs to infection, levels of both the enzymes decreased considerably. cathepsin d activity did not change to a signific ...	1980	7003382
characterization of surface proteins and glycoproteins on red blood cells from mice infected with haemosporidia: plasmodium berghei infections of balb/c mice.	the surface proteins and glycoproteins of red cells from plasmodium berghei-infected blood have been radio-isotope labelled and compared with those of normal mouse erythrocytes using the following protein labelling probes: lactoperoxidase-catalysed radio-iodination of tyrosyl residues, periodate oxidation and nab3h4 reduction of sialic acid and oxidation of galactosyl/n-acetylgalactosaminyl residues by galactose oxidase with subsequent nab3h4 reduction. during p. berghei infection, new tyrosyl-l ...	1980	7003500
plasmodium berghei and plasmodium knowlesi: serum binding to sporozoites.		1980	6768578
synthesis of 2,4-disubstituted 6-methoxy-8-aminoquinoline analogues as potential antiparasitics.	a series of 2,4-disubstituted 8-aminoquinoline analogues were synthesized and evaluated against plasmodium berghei in mice and leishmania donovani in hamsters. 8-[[6-(diethylamino)hexyl]amino]-2-ethyl-6-methoxy-4-methylquinoline (8a) possessed significant activity against l. donovani. 2-ethyl-4-methylprimaquine (7a) was evaluated against plasmodium cynomolgi in rhesus monkey and found to have activity equal to that of primaquine.	1980	6770089
plasmodium berghei: specific stimulation of rat lymphocytes by soluble antigens released in vitro from infected erythrocytes.		1980	6771155
4,5-disubstituted primaquine analogs as potential antiprotozoan agents.	4,5-dimethylprimaquine and 5-fluoro-4-methylprimaquine were synthesized and evaluated against plasmodium berghei in the mouse. significant blood schizonticidal activity was observed. the 5-fluoro-4-methylprimaquine analog also was active as a tissue schizonticidal agent when evaluated against p. cynomolgi in the rhesus monkey, as an antileishmanial agent when evaluated against leishmania donovani in the hamster, and as a causal prophylactic agent when evaluated against p. berghei yoelii.	1980	6772756
sporozoites of mammalian malaria: attachment to, interiorization and fate within macrophages.	sporozoites of plasmodium berghei and plasmodium knowlesi, incubated in normal serum readily interact with peritoneal macrophages of mice or rhesus monkeys, respectively. interiorization of the sporozoite requires that both serum and macrophages be obtained from an animal susceptible to infection by the malaria parasite. serum requirements for sporozoite attachment to the macrophage are less specific. phagocytosis is not essential for the parasites to become intracellular. our findings indicate ...	1980	6772771
plasmodium-infected blood cells analyzed and sorted by flow fluorimetry with the deoxyribonucleic acid binding dye 33258 hoechst.	red cells from plasmodium berghei infected mouse blood can be sorted on the basis of their dna content with the bisbenzimidazole dye 33258 hoechst. the optimal conditions for dye uptake have been established and with these conditions uninfected cells are nonfluorescent and can be completely separated from infected cells which exhibit fluorescence in almost direct proportion to the number of parasite nuclei (i.e. dna) they contain. the number of fluorescent cells detected and their fluorescence i ...	1979	87413
rapid detection of malaria and other bloodstream parasites by fluorescence microscopy with 4'6 diamidino-2-phenylindole (dapi).	dapi is a fluorescent dye which appears to complex specifically with dna. we have used this probe to detect and identify malarial infections by fluorescence microscopy. experiments were conducted using plasmodium berghei yoeli--infected mouse blood, p. lophurae--infected duck blood, and p. vivax--infected human blood. infected avian blood was used to detect parasites within nucleated erythrocytes. control blood smears from uninfected hosts revealed fluorescence only in the leukocytes of mammalia ...	1979	90141
plasmodium berghei - infected red cells sorted according to dna content.	a cell-sorting method is described for the analysis and separation of red blood cells in plasmodium berghei-infected mouse blood based on their dna content. this method involves a selective uptake of the bis-benzimidazole dye 33258 hoechst, a dna-binding dye, by red blood cells containing parasites. infected blood is incubated at 37 degrees c with the dye then washed at 4 degrees c to remove unbound dye. uninfected cells are then non-fluorescent at the characteristic wavelengths for 33258 hoechs ...	1979	90356
recent advances in applied malaria immunology.	our present knowledge of cellular and humoral factors which are involved in immunity to plasmodial infections are discussed. immunization against plasmodial infection has been achieved in birds, rodents, simians, and humans. avian hosts have been immunized against gametocytes which resulted in inhibition of gametocytes within the mosquito vector. immunization of humans against plasmodial gametocytes would indirectly protect them against malaria by blocking mosquito transmission to other suscepti ...	1979	93828
ia antigens in serum during different murine infections.	there exists in the mouse a family of i-region-controlled (ia) antigens which carry carbohydrate-defined determinants. these antigens appear in serum as glycolipids and seem to be actively secreted by antigen-activated t-cells. this paper describes the ability of selected viral, bacterial, and protozoal infections of mice to markedly alter the serum levels of these ia antigens. all the infectious agents examined induced substantial augmentation or suppression of serum ia concentrations or both. ...	1979	94905
synthesis of some 4-substituted 8-amino-6-methoxyquinolines as potential antimalarials.	the 4-vinyl, 4-ethyl, and three 4-[beta-(arylthio)ethyl] derivatives of primaquine and other 8-aminoquinoline antimalarial agents were prepared for antimalarial evaluation. 8-[(4'-amino-1'-methylbutyl)amino]-4-ethyl-6-methoxyquinoline (4-ethylprimaquine), which showed activity approximately equal to that of primaquine against plasmodia cynomolgi in rhesus monkey, was the most active of the compounds tested. 4-ethylprimaquine was also less toxic than primaquine, as measured in the rane mouse scre ...	1979	110932
correlation between genetic regulation of antibody responsiveness and protective immunity induced by plasmodium berghei vaccination.	high (h) and low (l) antibody responder lines of mice were produced by two independent bidirectional selective breedings for quantitative antibody responsiveness to heterologous erythrocytes (selection i and selection ii). in both selections the antibody response to p. berghei antigens was 8- to 10-fold higher in h than in l lines. the character "high response" presents an incomplete dominance o- 18% in selection i and 67% in selection ii. in selection ii the variance analysis indicates that at ...	1979	112057
studies on the 2,4-diamino-6 substituted quinazolines. i. antimalarial activities of 2,4-diamino-6-[(3,4-dichlorobenzyl)-nitrosoamino]-quinazoline (ci-679) as exhibited in rhesus monkeys infected with the ro or ro/pm strains of plasmodium cynomolgi.	this report summarizes the results of appraisals of various activities of ci-679 (a 2,4-diamino-6-amino-substituted quinazoline) in rhesus monkeys infected with the ro and ro/pm strains of plasmodium cynomolgi. in subjects inoculated with sporozoites, ci-679, administered in appropriate schedules in doses up to and including the maximum tolerated level, neither prevented development of infections with these strains nor cured those already established. although these evaluations showed that ci-67 ...	1979	114064
antimalarials. 11. synthesis of 3- and 5-aminoquinolines as potential antimalarials.	a series of 3-quinolinediamines (1g, 2c, and 3e) structurally related to primaquine and 4-methylprimaquine have been prepared and tested for antimalarial activity against plasmodium berghei in mice and antileishmanial activity against leishmania donovani in the hamster. all were inactive. in addition, three 5-quinolinediamines (4b, 5, and 6) were prepared. all were inactive against leishmania donovani in hamsters. one of the examples, 6, was curative against plasmodium cynmolgi in the rhesus mon ...	1979	114654
the development of a "high volume tissue schizonticidal drug screen" based upon mortality of mice inoculated with sporozoites of plasmodium berghei.	a biological test system has been developed to assess the prophylactic activity of compounds against sporozoite-induced plasmodium berghei malaria in mice. the procedure was designed to serve as the foundation of an effort to develop tissue schizonticidal drugs in a manner parallel to that of a previous system employed in the u.s. arym antimalarial drug development program to screen compounds for blood schizonticidal activity. in tests with 35 known antimalarial compounds, the new screen was fou ...	1979	116556
folate antagonists. 15. 2,3-diamino-6-(2-naphthylsulfonyl)quinazoline and related 2,4-diamino-6-[(phenyl and naphthyl)sulfinyl and sulfonyl]quinazolines, a potent new class of antimetabolites with phenomenal antimalarial activity.	oxidation of an array of 2,4-diamino-6-(arylthio)quinazolines provided the corresponding arylsulfinyl and arylsulfonyl analogues. a variety of these nonclassical analogues of methotrexate exhibited suppressive antimalarial activity superior to that of the parent thioquinazolines against drug-sensitive lines of plasmodium berghei in mice and p. gallinaceum in chicks, and several displayed potent prophylactic activity against p. gallinaceum. the sulfinyl- and sulfonylquinazolines also retained ant ...	1979	117107
synthesis of 4-alkyl and 4-(beta-alkylvinyl) derivatives of primaquine as potential antimalarials.	4(beta-alkylvinyl)-6-methoxy-8-nitroquinolines (6) were prepared from 6-methoxy-8-nitroquinoline-4-carboxaldehyde (5) via a wittig reaction. stannous chloride reduction of 6 gave 4-(beta-alkylvinyl)-8-amino-6-methoxyquinolines (8), whereas catalytic reduction of 6 using raney nickel catalyst gave 4-alkyl-8-amino-6-methoxyquinolines (7). alkylation of 7 and 8 with 4-iodo-1-phthalimidopentane, followed by removal of the phthaloyl-protecting group with hydrazine, gave 4-alkyl and 4-(beta-alkylvinyl ...	1979	118257
plasmodium berghei: suppression of antibody response to sporozoite stage by acute blood stage infection.		1979	118833
experimental nephritis associated with plasmodium infection in mice.		1979	119090
antimalarial activity of floxacrine (hoe 991) i. studies on blood schizontocidal action of floxacrine against plasmodium berghei, p. vinckei and p. cynomolgi.	floxacrine (hoe 991), 7-chloro-10-hydroxy-3-(4-trifluoromethylphenyl)3,4-dihydroacridine-1,9-(2h, 10h) dion, shows a high level of antimalarial action against blood-induced infection of drug-sensitive and drug-resistant lines of plasmodium berghei in mice, rats and syrian hamsters. the drug is also a potent blood schizontocide against drug-sensitive p. vinckei strains in rodents and p. cynomolgi in rhesus monkeys. the cd50/cd90 values against the drug-sensitive p. berghei strain ascertained in t ...	1979	120142
persistence and reactivation of rickettsia tsutsugamushi infections in laboratory mice.	the persistence of r. tsutsugamushi in tissues of experimentally infected mice for 565 days was demonstrated. reactivation of apparently dormant infections was accomplished by inoculating the mice with a heterologous strain of the organism or treatment with cyclophosphamide.	1979	120458
duration of immunity following a single vaccination with irradiated sporozoites of plasmodium berghei.	a rodent model of sporozoite immunization against malaria based on a single immunizing dose is described. the duration of protective immunity was measured as a function of dose, and the results suggest that the percentage of protection follows a bimodal distribution. the first peak occurs between days 7-12 after immunization, while the second peak occurs at approximately 28 days. although the percentage of protection declines steadily after the second peak, some immunity was detectable as long a ...	1979	120765
characterization of sporozoite surface antigens by indirect immunofluorescence: detection of stage- and species-specific antimalarial antibodies.	indirect immunofluorescence (if) was used to localize stage-specific antigen(s) on the surface of the sporozoite membrane. the authors examined the feasibility of using an if assay to determine whether an antisporozoite response is developed by individuals living in endemic areas. the specificity and sensitivity of the if assay were first defined by using hyperimmune sera of sporozoite-immunized hosts protected against rodent (p. berghei), simian (p. knowlesi), and human (p. falciparum, p. vivax ...	1979	120770
the use of membrane screen filters in the isolation of plasmodium berghei sporozoites from mosquitos.	an improved procedure is presented for the isolation of plasmodium berghei sporozoites from host mosquitos. the method employs filtration through a series of nuclepore membranes followed by two consecutive centrifugations of the filtrate layered over renografin-60 solutions of different densities. a coulter counter was used to compare isolations prepared by this technique with those prepared by a routinely employed discontinuous gradient method. when the sporozoite concentration in each preparat ...	1979	120775
low-temperature preservation of sporozoites of plasmodium berghei.	large numbers of biologically active sporozoites are needed as a source of potential antigen in the development of a malaria vaccine and the most practical method of accumulating sufficient numbers of these forms would be to freeze and store them at low temperature. the purpose of this work was to determine the feasibility of preserving the infectivity of frozen and thawed sporozoites. the results indicate that sporozoites of plasmodium berghei exhibit a typical response to freezing over a wide ...	1979	120776
particulate beta 1-3 glucan and casual prophylaxis of mouse malaria (plasmodium berghei).		1979	121199
chemotherapeutic studies with mefloquine and selection of a mefloquine resistant strain of plasmodium berghei.		1979	121298
dependence of plasmodial glutathione metabolism on the host cell.		1979	34799
rapid, large-scale isolation of plasmodium berghei sporozoites from infected mosquitoes.	the discontinuous gradient technique for recovery of malarial sporozoites from mosquitoes (beaudoin et al., 1977) has been modified to speed up recovery and prevent sensitization of mice by components of the gradient which contaminate the sporozoites used as antigen. mouse serum was substituted for bsa in the gradient because the latter produced hypersensitivity. best results were obtained with gradients consisting of medium 199, renografin and mouse serum. heavy and light solution of gradient c ...	1979	39127
malaria infection in mice. plasmodium berghei infection in mice: a model for immune complex disease and autoimmunity.		1979	157057
sarcomas induced by injection of simian virus 40 into neonatal cfw mice.	sarcomas were induced in cfw mice by the iv inoculation of simian virus 40 (sv40) in neonatal animals. infection with murine malaria parasites, plasmodium berghei yoelli, decreased the latency and increased the incidence and invasiveness of the tumors. all mice given both sv40 and p. berghei yoelli had sarcomas of the liver and spleen at 9 months of age. at 11 months of age, 70% of the sv40-inoculated mice had sarcomas of the liver indistinguishable from those in the group given both pathogens. ...	1979	225503
malaria enhances cyclic amp production by immature erythrocytes in vitro.		1979	225632
[antimalaria fluorescent antibodies evolution in young children living in a stable malaria area (author's transl)].	the detection of malarial fluorescent antibodies have been performed in an abidjan dispensary on 30 newborn babies with their mothers, 30 children 3 months old and 120 children from 6 to 24 months. this survey took place during the small rainy season and it demonstrates that: --synthesis of specific antibodies is significantly starting after the 3rd month; --the rise, after six months, of the malarial antibodies is parallel to the plasmodic index checked during the same period in the same area; ...	1979	231178
development and suppression of a population of late-adhering macrophages in mouse malaria.	changes in phagocytic and adherent cell numbers were compared during the course of infections of mice with plasmodium yoelii (py) and p. berghei (pb) and in vaccinated mice challenged with homologous parasites. nucleated cells in the spleen increased in number in py-infected mice and were maximal at the time of recovery. the number of phagocytic cells increased in parallel, as did the number of blood leucocytes. rates of increase were accelerated in vaccinated mice. changes in pb-infected mice r ...	1979	233150
the possible role of isoantigens in protective immunity to malaria.	the possibility that autoimmune responses to modified red cell antigens might be involved in protective immunity to malaria was investigated in plasmodium berghei infection of august rats. animals rendered anaemic by phenylhydrazine treatment at the time of immunization showed significantly greater protection than rats given antigen alone, or phenylhydrazine alone. adoptive transfer experiments indicated that this enhanced response could be transferred with spleen cells.	1979	317438
cellular aspects of immunoregulation in malaria.	malaria infection dramatically induces two nonspecific perturbations in immune responsiveness, polyclonal b cell activation and immunosuppression. polyclonal activation occurs early in infection and results in secretion of antibodies that lack antiplasmodial specificity. immunosuppression occurs later in infection and is characterized by blunted humoral and cellular immune responses to heterologous (nonplasmodial) as well as plasmodial antigens. previous studies have suggested that defects in ma ...	1979	317442
alterations in membrane proteins of mouse erythrocytes infected with different species and strains of malaria parasites.	1. the membrane fraction, prepared by hypotonic lysis, of mouse red cells infected with plasmodium berghei, p. yoelii ym, p. yoelii 17 x, p. yoelii 33 x, p. vinckei or p. chabaudi shows significant alterations from normal in protein composition as observed by dodecylsulphate-polyacrylamide gel electrophoresis. 2. there is a reduction in intensity of various protein bands, notably bands i and ii (spectrin), of membranes prepared from infected red cells. 3. new bands are observed as a result of in ...	1979	318403
dissociative effects of malarial infection on humoral and cell-mediated immunity in mice.	the effect of malarial infection on immune responses was studied in mice. when sheep red blood cells (srbc) were injected 2 days before or at the same time as infection with plasmodium berghei, there was a marked increase in the number of splenic plaque forming cells (pfc) induced by srbc as compared with uninfected controls. when srbc were injected 2 days or more after the infection, however, the pfc response was significantly reduced. on the other hand, cell-mediated immunity, as exemplified b ...	1979	381176
alterations in some biochemical parameters in mouse liver and spleen during infection with plasmodium berghei.		1979	381192
host defenses in murine malaria: analysis of the mechanisms of immunity to plasmodium berghei generated in response to immunization with formalin-killed blood-stage parasites.	syngeneic b6d2f1 (c57bl/6 x dba/2) mice were immunized with a nonliving antigen prepared from mixed blood forms of plasmodium berghei strain nyu-2. consistently greater than 80% of the vaccinated mice survived virulent challenge, and protective immunity was demonstrable from 1 week through at least 4 months after immunization. however, vaccination did not prevent the development of patient infection after challenge. instead, infections in vaccinated mice progressed to about 10% parasitemia and w ...	1979	381198
electron microscopy of cerebral malaria in golden hamsters (mesocricetus auratus) infected with plasmodium berghei.	transmission and scanning electron microscopy of hamster cerebral malaria show that haemorrhages occur following vessel necrosis in animals with low parasitaemias. there is no concurrent thrombosis nor packing of capillaries with parasitised erythrocytes. small vessels contain numerous monocytes which have phagocytosed erythrocytes and smaller particles of similar electron density. the monocytes attach to and migrate through the endothelium but then remain in close proximity to the vessels. irre ...	1979	381611
immunopathological studies of plasmodium berghei infected mice: (effect of carbon particles).	an attempt was made to block the role of the macrophages in the immune response by saturating them with carbon particles. the experiment was performed on swiss albino female mice injected intraperitoneally with 10(5) p. berghei berghei. these mice were injected with carbon particles of 20 mgs on the day before the inoculation and again 10 mgs on day 4 and day 9 after the inoculation. the degree of parasitaemia was slightly higher throughout the experiment in the infected mice treated with carbon ...	1979	381681
sporozoite-induced malaria: therapeutic effects of glycolipids in liposomes.	liposomes containing neutral glycolipids with a terminal glucose or galactose, when injected intravenously, prevented the appearance of erythrocytic forms of malaria (plasmodium berghei) in mice previously injected with sporozoites. inhibitory glycolipids included glucosyl, galactosyl, or lactosyl ceramide. inhibition was not observed with liposomes containing ceramide, phosphocholine ceramide, sulfogalactosyl ceramide (sulfatide), or ganglioside gm1. liposomes containing glycolipids did not inh ...	1979	382358
liposomes in the chemotherapy of experimental murine malaria.		1979	382476