| [the in-vitro action of chloroquine on the infectivity of gametocytes of plasmodium berghei anka]. | the influence of chloroquine on the infectivity of gametocytes of p. berghei anka chloroquino-sensitive was assessed in vitro. it was found that chloroquine could not affect the exflagellation of microgametocytes but prevented the formation of ookinetes at the concentration of 10 micrograms/ml. this activity seemed to be stage and dose dependent. | 1989 | 2692524 |
| changing pattern of antimalarial drug resistance. | with the current increase of international travel and increasing drug resistance, united kingdom residents stand a high risk of contracting malaria when they visit endemic countries. the development of anti-malarial agents from old traditional plant remedies to modern synthetic drugs is briefly reviewed. resistance to the latter has spread rapidly since the 1950s, culminating in the widespread distribution of multiple drug-resistant strains of plasmodium falciparum in most endemic areas. there i ... | 1989 | 2693718 |
| presence of contaminating mitochondrial dna from host reticulocytes in experimental infections of plasmodium berghei. | 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 extracted from leucocyte-free blood containing synchronous parasites at early stages of infection. these discrete dna fragments cross-hybridize with host cell mitochondrial dna. purific ... | 1989 | 2693960 |
| significance of blood urea nitrogen as an index of renal function in mice infected with plasmodium berghei. | parameters of renal function were evaluated in severe malarial infection, using mice infected with plasmodium berghei. when 7-week-old male balb/c mice were inoculated with 1 x 10(7) p. berghei nk65-infected red blood cells, the rodents died an average of 7.4 days after inoculation. anemia developed on day 5 after inoculation and progressed markedly on days 6 and 7. plasma urea nitrogen increased rapidly on day 6 or 7, after which death occurred within 24 h. in contrast, urinary urea nitrogen ex ... | 1989 | 2694168 |
| antiplasmodial activity of an aqueous infusion prepared from brucea javanica fruits against plasmodium falciparum and p. berghei. laboratory meeting, london school of hygiene and tropical medicine. 17 november 1988. abstracts. | | 1989 | 2694473 |
| [pharmacodynamics of dihydroartemisinine against plasmodium berghei in mice]. | dihydroartemisinine (dha) is a derivative of qinghaosu(artemisine), which is an antimalarial drug. dha was given to mice inoculated with plasmodium berhgei anka strain by intramuscular injection. within proper dose range, the dose-effect and time-effect curves of dha against the malaria can be described by y = 4.9960 + 2.9536 x and y = 7.2654 - 0.3414 t, respectively, where y is the estimated value of parasitemia suppressing rate in probit; x is log dose; t is the period since drug administratio ... | 1989 | 2694757 |
| [synthesis and antimalarial and antineoplastic activities of some derivatives of 2,4-diamino-5-methyl-6-substituted benzylaminoquinazolines]. | this paper reports the synthesis and the antimalarial and anticancer activities of some derivatives of 2,4-diamino-5-methyl-6-substituted benzylaminoquinazolines. these compounds were synthesized by condensation of 5-methyl-2,4,6-triaminoquinazoline with substituted benzyaldehyde to produce schiff base, followed by reduction, formylation or nitrosation. the suppressive therapeutic effects against plasmodium berghei in mice showed that the suppressive rate of three compounds (iv 2,5,6)was 100 per ... | 1989 | 2694758 |
| immunoprotection by beta-1,3 glucan antigen combination in plasmodium berghei infection in mice. | in an attempt to protect mice against experimental infection with p. berghei, mice were immunized against soluble extract of p. berghei in combination with beta-1,3 glucan or fca and also independently. mice immunized against p. berghei antigen-glucan developed well defined cell mediated and humoral immune responses, while mice injected with antigen fca or antigen alone developed only an antibody response. antigen-glucan immunization afforded a high degree of immune protection to the host agains ... | 1989 | 2695459 |
| interactions between vitamin a deficiency and plasmodium berghei infection in the rat. | it has been claimed that vitamin a deficiency increases the severity of malarial infection in rats. we measured parasitemia, mortality, serum retinol, liver retinol, spleen weight, and degree of xerophthalmia in vitamin a-deficient rats (a-), pair-fed control rats (a+pf), and ad libitum-fed control rats (a+al) infected with plasmodium berghei, a rodent malarial parasite. in experiments 1 and 2 vitamin a deprivation began at weaning. parasitemia and mortality among mildly deficient (expt. 1, mean ... | 1989 | 2695606 |
| plasmodium falciparum ookinetes migrate intercellularly through anopheles stephensi midgut epithelium. | the migration of plasmodium falciparum and p. berghei ookinetes through the midgut epithelium in anopheles stephensi was studied by transmission electron microscopy. with ruthenium red (rr) staining, the results of previous studies were confirmed: p. falciparum ookinetes take an intercellular route through the midgut epithelium. in the same mosquito species, the rodent parasite p. berghei appeared to take an intracellular position, as previously suggested by other authors. the intra- or intercel ... | 1989 | 2695921 |
| cerebral lesions in mice infected with plasmodium berghei are the result of an immunopathological reaction. | cerebral lesions in mice with plasmodium berghei infections can be prevented by timely treatment with immune serum, by splenectomy, and by administration of dexamethasone. t cell deficient mice do not develop cerebral lesions. the results of these studies are compatible with the hypothesis that a pathological reaction is responsible for development of cerebral lesions in mice infected with p. berghei. | 1989 | 2696153 |
| [complete inhibition of cyclic transmission by immunization against plasmodium berghei anka ookinetes]. | an antiserum raised against p. berghei anka ookinetes binds specifically to ookinetes and zygotes surface as assessed by indirect immunofluorescence. the transmission blocking activity of this serum was assessed by feeding mosquitoes on immunized mice. a serum showing an antibody titer of 1/320 reached after 6 immunizations completely blocks ookinetes development. this immune serum might be used to screen p. berghei genomic or cdna library in order to identify or clone sequences involved in the ... | 1989 | 2696409 |
| hepatoprotective activity of silymarin against hepatic damage in mastomys natalensis infected with plasmodium berghei. | silymarin, a flavolignan from the seeds of silybum marianum, showed significant hepatoprotective activity in p. berghei-induced hepatic damage in m. natalensis, as assessed by changes in several serum and liver biochemical parameters. changes in lipoprotein-x, got, gpt, alkaline phosphatase and bilirubin were found to be protected by silymarin at different doses. maximum activity was observed at a dose of 5 mg/kg bw, po. silymarin had no effect on parasitaemia. | 1989 | 2697691 |
| benzoxazinone derivatives: new fluorescent probes for two-color flow cytometry analysis using one excitation wavelength. | a new class of fluorescent dye which upon excitation at 488 nm turns red is shown to be probe-suitable for using in flow cytometry alone or in conjunction with fluorescein derivatives. 7-dimethylamino 3-(p-formylstyryl) 1,4 benzoxazin 2-one is suitable for rendering microorganisms, such as plasmodium merozoites and cells detectable by flow cytometry, allowing a dual fluorescence analysis when the cells are labelled with suitable fluoresceinylated ligands such as fluorescein labeled neoglycoprote ... | 1989 | 2698760 |
| hepatic low density lipoprotein receptor binding and lipid profile in mastomys natalensis during plasmodium berghei infection. | plasmodium berghei infection to mastomys natalensis showed hyper beta-lipoproteinemia. the increase in serum cholesterol is associated with decreased uptake of low density lipoprotein (ldl) by the liver through receptor mediated endocytosis. the membranes prepared from infected m. natalensis exhibit up to 50% decline in high affinity binding sites for human 125i-ldl. significant increases in serum lipids, cholesterol, triglyceride and lipid peroxide (lpo) contents of liver membrane were observed ... | 1989 | 2698856 |
| evaluation of ciep and elisa in a rodent malaria model. | circulating antigens could be detected by both elisa and ciep in the sera of mice infected with plasmodium berghei. however, elisa was positive for circulating antigen even though the giemsa stained smears did not show significant parasites. hence, elisa can have a diagnostic value for detection of antigens as a marker of active infection. | 1989 | 2698862 |
| in vitro culture of erythrocytic stages, including gametocytes of plasmodium berghei (nk 65 strain) using candle jar method and a newly designed continuous medium flow apparatus. | three methods have been described for cultivation of erythrocytic stages, specially gametocytes of p. berghei nk65 strain, (1) by using vial candle jar where the cultures were subcultured by addition of fresh erythrocytes, (2) a newly designed simple and compact continuous medium flow apparatus, where medium was continuously perfused but fresh erythrocytes were not added and (3) where the subcultures were also done using simple and compact continuous medium flow apparatus for comparison. the max ... | 1989 | 2699308 |
| the antioxidants as protectors of host stress organ injury in mice infected with plasmodium berghei. | a study has been made of counteracting the stress organ injury in plasmodium infection by means of antioxidants on the premise that free radicals are responsible for causing the injury to stress organs. this was evidenced by drastically altered biochemical parameters in liver and spleen of the host in terms of elevated levels of lipid peroxides and xanthine oxidase (xo) activity, and a fall in superoxide dismutase activity coupled with other drastic biochemical changes. the cardinal factor respo ... | 1989 | 2699864 |
| ultrastructural comparison of erythrocytic stages of experimentally selected drug resistant strains of rodent malaria parasite p. berghei with its susceptible strain. | studies on ultrastructure of drug-resistant strains of plasmodium berghei have been mostly restricted to the experimentally selected chloroquine and pyrimethamine resistant strains. study of the morphology of mefloquine and quinine resistant strain of p. berghei has been carried out to demonstrate some differences between normal and drug-resistant strains. the main differences are concerned with a complex physiological process i.e., food ingestion and digestion. e.m. studies reveal that in the s ... | 1989 | 2699865 |
| [synthesis and antimalarial as well as antitumor activities of 1-methyl-2,4-diamino-6-(n-methyl-substituted benzylamion) quinazolinium iodides]. | fourteen 1-methyl-2,4-diamino-6-(n-methyl-substituted benzylamino) quinazolinium iodides (ii) were synthesized by treatment of 2,4-diamino-6-substituted benzylaminoquinazolines with methyl iodide. three compounds (ii4,7,10) were shown to produce 100% suppression on plasmodium berghei in mice at oral dose of 20 mg/kg and ii4 was found to inhibit twice as much as methotrexate on l1210 leukemia cells in culture. | 1989 | 2700414 |
| characterization of a model of malaria in the pregnant host: plasmodium berghei in the white rat. | this study characterizes a plasmodium berghei white rat model of p. falciparum malaria in the pregnant human. seventy-day-old and 114-day-old female rats, given an infecting inoculum at time of mating, had higher parasitemias and a more severe anemia than age- and sex-matched controls. under these experimental conditions, the parasitemia went to crisis in all animals and there were no fatal infections. in contrast, all animals died when the infection was initiated 7 days after conception, a timi ... | 1989 | 2701632 |
| tumor necrosis factor alpha and the anemia associated with murine malaria. | the anemia associated with malaria is complex, and multiple factors contribute to its severity. an increased destruction and a decreased production of erythrocytes are involved; however, the mechanisms responsible remain unclear. tumor necrosis factor alpha (tnf-alpha), released by macrophages in response to infection, is thought to play a role through its ability to inhibit erythropoiesis. in these studies we have examined erythropoiesis in mice infected with plasmodium berghei and in mice infu ... | 1989 | 2707858 |
| effects of pyran copolymer on host resistance of mice to plasmodium yoelii. | female b6c3f1 mice treated with 25 mg/kg pyran intravenously (i.v.) on days -4 and -3 were more susceptible to nonlethal plasmodium yoelii 17xnl or lethal plasmodium berghei atcc-30090 than untreated mice or mice treated intraperitoneally (i.p.). female b6c3f1 mice treated with pyran i.p. displayed enhanced resistance to listeria monocytogenes as compared to untreated mice or mice given pyran i.v. peritoneal exudate cells (pec) primed by pyran i.p. possessed enhanced ability to kill listeria but ... | 1989 | 2723926 |
| spectrum of the antimalarial activity of a new macrolide antibiotic midecamycin in mice and monkeys. | the antimalarial activity of a new macrolide antibiotic, midecamycin, has been evaluated against a sensitive strain of plasmodium berghei, a chloroquine-resistant strain of p. yoelii nigeriensis and a simian parasite, p. cynomolgi b. the ed50 and ed90 values of this antibiotic administered in two divided daily doses were found to be 37.15 +/- 3.51 and 100.84 +/- 7.54 mg/kg, respectively, against p. berghei and 362.34 +/- 85.33 and 878.04 +/- 10.02 mg/kg, respectively, against p. yoelii nigeriens ... | 1989 | 2766859 |
| tricyclic 2,4-diaminopyrimidines with broad antifolate activity and the ability to inhibit pneumocystis carinii growth in cultured human lung fibroblasts in the presence of leucovorin. | a selected number of 1,3-diaminobenzo[f]quinazolines and 1,3-diamino-5,6-dihydrobenzo[f]quinazolines, which may be viewed as tricyclic analogues of the lipid-soluble antifolates pyrimethamine (pm), metoprine (ddmp), and etoprine (ddep), were tested as inhibitors of purified dihydrofolate reductase (dhfr) from wi-l2 lymphoblasts, and as inhibitors of the growth of streptococcus faecium atcc 8043 and l1210 murine leukemia cells in culture. in addition, these tricyclic compounds were tested for ant ... | 1989 | 2788420 |
| fractionation of mouse malarious blood according to parasite developmental stage, using a percoll-sorbitol gradient. | asexual intraerythrocytic malarial parasites permeabilize the membrane of their host cell to small monelectrolytes and anions. since permeabilization increases with parasite maturation, this property has been used previously to fractionate blood infected with plasmodium falciparum and p. knowlesi according to the developmental stage of the parasite, using percoll-sorbitol density gradients. we have extended this method to fractionate mouse blood infected with four species of rodent malaria: p. c ... | 1987 | 2827557 |
| effect of solanum erianthum aqueous leaf extract on plasmodium berghei in mice. | the aqueous leaf extract of solanum erianthum collected in may was administered orally to albino swiss mice infected with plasmodium berghei berghei. the schizontocidal activity on early infection was assessed by administering the extract of s. erianthum, chloroquine, or distilled water as single daily dose from the day of infection for 4 days. microscopic examination made on the fifth day from all the mice, showed s. erianthum extract producing a dose-related schizontocidal effect, with the hig ... | 1987 | 2830780 |
| primary sequences of two small subunit ribosomal rna genes from plasmodium falciparum. | we have determined the complete sequence of two structurally distinct 18s ribosomal rna genes from the malarial parasite plasmodium falciparum. s1 nuclease analyses demonstrate that only one of the genes is represented in stable rrna populations isolated from blood-stage parasites. comparisons of homologous rrna genes from plasmodium berghei and p. falciparum reveal that they are identical at 86% of their positions. from comparisons of the plasmodium genes to that of humans, it was possible to d ... | 1988 | 2836731 |
| c3b inactivator in normal mice and mice infected with plasmodium berghei berghei. | c3b inactivator levels were assayed in clean albino mice and mice infected with plasmodium berghei berghei. infected animals (63.1%) had low c3b inactivator levels when compared with 45% of controls with low levels. in the low titre range, infected mice had a significantly lower mean level (p less than 0.001) of the factor than controls. conversely, in the high titre range, the mean c3b inactivator level is significantly (p less than 0.001) higher in infected than in control mice. lower levels o ... | 1988 | 2845758 |
| re-examination of earlier work on repetitive dna and mosquito infectivity in rodent malaria. | previous results, relating mosquito infectivity to percentage of repetitive dna in the genome of plasmodia, are re-examined in the light of the finding that a parasite line used in the previous studies and classified as plasmodium berghei nk65, was a mixed infection, where the major component appeared to be plasmodium yoelii. this conclusion was reached through cloning and isoenzyme typing of different clones. isoenzyme typing alone is not sufficiently sensitive to reveal contamination amounting ... | 1985 | 2863751 |
| in vitro formation of ookinetes and functional maturity of plasmodium berghei gametocytes. | in vitro formation of plasmodium berghei ookinetes was studied. gametocytes produced in vitro were obtained from heart and tail blood of swiss mice and from blood removed from mosquitoes directly after feeding on these mice. in vitro produced gametocytes were obtained from short-term cultures of the erythrocytic stages of p. berghei. reproducible ookinete production was obtained in medium rpmi 1640, ph 7.8-8.0, using in vivo and in vitro produced gametocytes. the morphology of developmental stag ... | 1985 | 2863802 |
| the sustained release of pyrimethamine base or pyrimethamine pamoate from a biodegradable injectable depot preparation in mice. | the pharmacokinetics and mass fate in mice, of pyrimethamine (425 mg kg-1 s.o.) administered subcutaneously either as the base (base) or the pamoate salt (pam) in an injectable oil mixture (benzyl benzoate-peanut oil 50:50 v/v) have been evaluated. maximum measured plasma pyrimethamine levels after base were attained within 24 h, and were twice as high as after pam. 25% of animals dosed with base died; among the survivors plasma drug levels fell rapidly below the minimum inhibitory concentration ... | 1985 | 2868095 |
| plasmodium berghei-infected mice: lack of effect of meclizine and cimetidine on the development of pulmonary oedema. | the involvement of histaminergic mechanisms in the pathogenesis of pulmonary oedema observed in plasmodium berghei-infected mice was investigated. histamine concentrations in plasma and whole blood of infected and normal mice were determined by radioenzymatic assay during the seven days of the infection. elevated plasma and whole blood histamine levels were found at the last stages of infection (sixth day and seventh day after ip injection of parasitized erythrocytes), showing a close temporal c ... | 1986 | 2888439 |
| comparison of repeated dna from strains of entamoeba histolytica and other entamoeba. | restriction enzyme digestion patterns of total genomic dna revealed the presence of highly repeated dna in entamoeba histolytica and e. histolytica-like (laredo type) amoebae of humans, e. invadens and e. invadens and e. terrapinae of reptiles, and e. moshkovskii isolated from sewage polluted waters. homology with plasmodium berghei ribosomal dna was striking. northern blot analysis of e. histolytica rna provided further evidence that the highly repeated dna codes for ribosomal rna. the distribu ... | 1988 | 2893976 |
| [response of the plasmodium berghei anka strain to some antimalarials]. | | 1985 | 2934947 |
| [the effect of qinghaosu on the pfc and rfc of mice infected with plasmodium berghei]. | | 1985 | 2936520 |
| surface plasmodium sugar-binding components evidenced by fluorescent neoglycoproteins. | a sugar-binding component was shown to be present at the surface of endoerythrocytic plasmodium berghei and p. chabaudi stages and merozoites by means of a panel of neoglycoproteins using fluorescence microscopy and flow cytofluorometry. the protein nature of this material was ascertained by the loss of sugar-binding capacity upon trypsin treatment. this lectin-like protein primarily bound neoglycoprotein-borne n-acetylglucosamine and secondarily bound neoglycoprotein-borne alpha-d-glucose, beta ... | 1986 | 2941097 |
| [stability of drug resistance of a pyronaridine-resistant line of plasmodium berghei]. | | 1985 | 2943123 |
| [effect of pyronaridine on ultrastructure of erythrocytic forms of plasmodium berghei in mice]. | | 1985 | 2945375 |
| [effects of piperaquine on the fine structure of the erythrocytic stages of plasmodium berghei anka strain]. | | 1986 | 2954398 |
| [delay in emergence of resistance to pyronaridine phosphate in plasmodium berghei]. | | 1986 | 2954424 |
| [effects of artemether on red blood cell immunity in malaria]. | | 1986 | 2954426 |
| antimalarial activity of tripynadine in mice and monkeys. | | 1987 | 2955662 |
| interferon-gamma inhibits the intrahepatocytic development of malaria parasites in vitro. | in this study, we examined the activity of recombinant interferon (ifn)-gamma against plasmodium berghei exoerythrocytic forms (eef) grown in vitro within the highly differentiated human hepatoma cell line hepg2. we assayed the effect of ifn-gamma on parasite growth by dna hybridization using a p. berghei specific dna probe. the specific activity of ifn-gamma against eef is very high, and depends upon the time of lymphokine addition. when ifn-gamma is added to hepg2 cells containing intracellula ... | 1987 | 2957445 |
| [development of a line of plasmodium berghei resistant to sodium artesunate]. | | 1987 | 2959002 |
| plasmodium berghei: lymphocyte and macrophage dynamics in the spleen of balb/c mice in the course of infection and after rechallenge of cured mice. | the purpose of this study was to determine a possible correlation between the cell populations of the immune system in the spleen, and the failure of normal balb/c mice to overcome a plasmodium berghei infection. after primary infection, all splenic white cell populations increased in number. however, the ratios between the different cell populations changed markedly. macrophages, which comprise 5-10% of normal white spleen cells, rose to 70-80?% during the lethal infection. most of the macropha ... | 1988 | 2962882 |
| manifestation of cerebral malaria-like symptoms in the wm/ms rat infected with plasmodium berghei strain nk65. | conditions required for the induction of cerebral malaria (cm)-like symptoms were investigated using 12 strains of rats and 5 murine malaria strains. among various combinations, only inbred wm/ms rats infected with p. berghei (nk65) developed neuropathological complications that closely resembled human cm cases. when young wm/ms rats were infected with the parasites, neurologic signs were induced followed by death in 5-10 days with almost 100% incidence, whereas aged hosts revealed strong resist ... | 1987 | 2963898 |
| a kinetic model of phosphofructokinase from plasmodium berghei. influence of atp and fructose-6-phosphate. | phosphofructokinase (pfk) from the malarial parasite plasmodium berghei shows the following kinetic features: the more the ph is decreased, the more the enzyme is inhibited by atp; in contrast to pfk from erythrocytes, this inhibition is less potent by two orders of magnitude; as in the red cell, fructose-6-phosphate (f6p) is a positive effector. kinetic modelling of pfk from p. berghei has been performed by taking the ph-dependence of activity into regard, implicitly by the estimation of ph-dep ... | 1988 | 2963958 |
| induction of macrophage motility by a t-cell line from balb/c mice specific for plasmodium berghei malaria. | a long-term antimalaria t-cell line (amtl) expressing a helper phenotype (thy 1.2+, lyt 2.2-) was established from plasmodium berghei-recovered balb/c mice. the ability of this t-line to induce macrophage motility was measured in vivo and in vitro. adoptive transfer of amtl cells to normal balb/c mice showed an increased delayed hypersensitivity response to the homologous antigen, i.e., parasitized erythrocytes (pe). in vitro, amtl culture supernatant (amtl-sup) augmented chemotactic locomotion ... | 1988 | 2973521 |
| impairment of t-helper function by a plasmodium berghei-derived immunosuppressive factor. | mice injected with an immunosuppressive factor (isf) extracted from plasmodium berghei-infected rat erythrocytes have a reduced antibody response to unrelated antigens. t-cells from isf-treated mice failed to provide adequate help to naive, syngeneic b-cells in the primary igm response in vitro to sheep red blood cells and to dinitrophenylated keyhole limpet hemocyanin. the same t-cells, however, were able to cooperate with memory b-cells in the secondary igg response. no other cellular deficit ... | 1988 | 2974077 |
| immunoradiometric assay to measure the in vitro penetration of sporozoites of malaria parasites into hepatoma cells. | we describe here an immunoradiometric assay to quantitate the in vitro invasion of hepatoma cells by sporozoites. the assay measures levels of circumsporozoite (cs) antigen that remain associated with the hepatoma cells after their incubation with the parasites. several observations show that these measurements reflect internalized rather than extracellular antigen. for example, when incubations were performed with nonviable parasites (sonicated or heated), or in the presence of metabolic inhibi ... | 1985 | 2981261 |
| in vitro cultivation of the exoerythrocytic stage of plasmodium berghei in irradiated hepatoma cells. | growth of cultures of human hepatoma cells was inhibited by exposure to doses of gamma irradiation as low as 1,000 rad., and the monolayers remained viable for up to 35 days. irradiated cells were at least as susceptible to plasmodium berghei sporozoite invasion as non-irradiated cells, and supported the entire exoerythrocytic cycle producing more infectious merozoites. irradiated cultures may have use for culture of human malarias, and drug studies requiring synchronous cultures. | 1985 | 2982289 |
| acth-dependent modulation of malaria immunity in mice. | tetracosactrin, a synthetic adrenocorticotrophic hormone (acth) analogue delivered by osmotic minipumps implanted s.c. in mice induced a dose-dependent increase of plasma corticosterone levels. in mice with an established immunity to plasmodium berghei the increase of the plasma corticosterone level due to tetracosactrin treatment correlated with loss of immunity against this malaria parasite. the observed plasma corticosterone levels associated with loss of malaria immunity were of the same ord ... | 1985 | 2987773 |
| plasmodium berghei: inhibitors of ornithine decarboxylase block exoerythrocytic schizogony. | dl-alpha-difluoromethylornithine and dl-alpha-monofluoromethyldehydroornithine methyl ester, inhibitors of ornithine decarboxylase, blocked exoerythrocytic schizogony of plasmodium berghei in mice and in cultured human hepatoma cells. these effects were reversed by exogenous administration of the polyamine, spermidine. the antimalarial drug, primaquine, the side chain of which is structurally analogous to a natural polyamine, did not enhance the activity of alpha-difluoromethylornithine or alpha ... | 1985 | 2990989 |
| investigations of various extracts of morinda lucida for antimalarial actions on plasmodium berghei berghei in mice. | morinda lucida extracts, the stem bark, the root bark and the leaves were screened for antimalarial activity in a "4-day schizontocidal test' against a chloroquine-sensitive strain of p. berghei berghei in mice. each extract was administered as a single daily dose on days 0, 1, 2 and 3 to mice that had received an intraperitoneal inoculum of 1 x 10(7) infected erythrocytes. each extract produced a degree of suppression of parasitaemia. the most promising result was obtained with chromatographic ... | 1985 | 2994438 |
| effect of azadirachta indica on plasmodium berghei berghei in mice. | azadirachta indica leaf extract has been investigated for antimalarial activity against drug sensitive strain of p. berghei berghei in mice. on administering the extract subcutaneously to infected mice in the "4-day schizontocidal test' 41.2% suppression of parasitaemia was observed. a similar observation was made when the extract was injected for 3 days before the animals were infected with the parasites, 21.7% chemosuppression was obtained. when treatment commenced after the infection had alre ... | 1985 | 2994439 |
| lack of schizontocidal activity of three herbal decoctions on plasmodium berghei berghei in mice. | this work reports the effects of three herbal decoctions on plasmodium berghei berghei in mice. the schizontocidal activity of each decoction was determined on an established infection using chloroquine as a standard and distilled water as control. also a repository study of the decoction was carried out in another group of mice. the three decoctions neither reduced parasitaemia nor prolonged the life of infected mice that received them. | 1985 | 2994440 |
| screening of morinda lucida leaf extract for antimalarial action on plasmodium berghei berghei in mice. | the leaf extract of morinda lucida collected in august was administered subcutaneously to albino swiss mice infected with p. berghei berghei. the schizontocidal activity on early infection was assessed by administering chloroquine (standard) distilled water or morinda lucida as single daily dose on day 0-3 to infected mice. on day 4 the degree of parasitaemia and percentage was determined in relation to control. its schizontocidal activity was also observed on an established infection by adminis ... | 1985 | 2994441 |
| identification of a telomeric dna sequence in plasmodium berghei. | a fragment of plasmodium berghei dna was cloned using a technique designed to select for telomeric sequences. the cloned fragment recognizes bal31-sensitive bands in p. berghei genomic digests. it contains at its distal end at least 70 tandem repeats of the heptanucleotide sequence ccctgaaa. the presence of natural single strand discontinuities in the telomeric regions of p. berghei dna is demonstrated by the selective incorporation of deoxyribonucleoside triphosphates in the absence of dnase. t ... | 1985 | 2998771 |
| magnetic resonance studies of the pathophysiology of murine malaria. | | 1985 | 2999860 |
| [inhibition of plasmodium berghei in rats infested with strongyloides ratti or trichinella spiralis; role of high blood corticosterone in reaction to the development of helminths]. | the plasma corticosterone induced in the rat by the development of strongyloides ratti or trichinella spiralis reaches a sufficient level of intensity to determine reticulocytopenia. the latter is linked chronologically to the inhibition of parasitemia in plasmodium berghei, which occurs when this protozoa develops at the same time as the nematodes, and seems to be the causal factor. this hypothesis may be verified by replacing the helminths with the corticotropic action of a.c.t.h. which causes ... | 1985 | 3002223 |
| antimalarial agents, 2. artesunate, an inhibitor of cytochrome oxidase activity in plasmodium berghei. | the activity of the cytochrome oxidase, which is located in the plasma and the nuclear and the food-vacuole-limiting membranes as well as in the mitochondria of the trophozoites of plasmodium berghei, was inhibited completely by sodium artesunate, an antimalarial drug, in vitro at 1 mm and in vivo at 100 mg/kg iv. this enzyme appears to be a target for the antimalarial mechanism of action of artesunate and qinghaosu. | 1986 | 3009719 |
| purification and characterization of plasmodium berghei dna topoisomerases i and ii: drug action, inhibition of decatenation and relaxation, and stimulation of dna cleavage. | it has recently been suggested that topoisomerases could be important targets for drugs used in several diseases. this prompted us to purify and characterize the topoisomerases i and ii present in the erythrocytes of protozoan parasites of the genus plasmodium, the causative agent of malaria, in order to later use these enzymatic systems in antimalarial drug assays. the topoisomerases were purified from plasmodium berghei, a parasite of mouse red cells. the plasmodium topoisomerase ii consists o ... | 1986 | 3011062 |
| effects of antimalarial drugs on oxygen consumption by erythrocytes infected with plasmodium berghei: an esr study. | oxygen consumption in mouse erythrocytes infected with plasmodium berghei has been followed by electron spin resonance (esr) spectroscopy of nitroxide radical spin probes. the parasitized red cell suspension is mixed with the spin probe ctpo (3-carbamoyl-2,2,5,5-tetramethyl-3-pyrrolin-1-yloxy) in a closed chamber. oxygen consumption is monitored by the increasing resolution of the superhyperfine splittings of the spin label. the antimalarial drugs quinacrine, primaquine, and quinine are shown to ... | 1986 | 3012241 |
| plasmodium berghei: reaction of sporozoites with chemically and enzymatically modified hepatoma cells. | plasmodium berghei sporozoites were observed to react with human hepatoma (hepg2) target cells which had been fixed with methanol, formaldehyde, or glutaraldehyde. the reaction consisted of attachment of sporozoites to the fixed target cells and the release of circumsporozoite protein which bound to target cell areas adjacent to the attachment sites. treatment of fixed target cells with 0.1 n h2so4 at 80 c, neuraminidases, neuraminidase plus galactose oxidase or inclusion of transferrin, orosomu ... | 1986 | 3013669 |
| cephalo-adrenal interactions in the broader context of pragmatic and theoretical rhythm models. | some of the literature on modeling of biological rhythms with mathematical, physical, chemical, biochemical, in vivo and in vitro oscillations is succintly annotated. the need for biologic models that account for the interaction of 3 or more periodic entities is indicated, documented and illustrated, with emphasis on the cephalo-adrenal network of rodents. patterns of interaction, in this context, involve attenuation, no-effect and/or amplification by a third entity, the modulator, of the effect ... | 1986 | 3015508 |
| homologous telomeric sequences are present in different species of the genus plasmodium. | the telomeric sequence cloned from plasmodium berghei (see m. ponzi et al. (1985) embo j. 4, 2991-2995) was tested for species specificity. a telomeric and a subtelomeric fragment of the cloned insert served as separate, labelled probes on pulsed field gradient electrophoretical patterns and on genomic digests from the rodent malarias plasmodium yoelii, plasmodium chabaudi and from the human malaria plasmodium falciparum. results indicate that the subtelomeric fragment, abundantly represented in ... | 1986 | 3024000 |
| tandemly arranged gene clusters of malarial parasites that are highly conserved and transcribed. | a molecular clone containing a 5.8 kb eco ri fragment was isolated from a genomic library of the rodent malarial parasite plasmodium yoelii. the p. yoelii genome contains about 150 copies of this sequence, making up almost 3% of the dna. these sequences are tandemly arrayed in head-to-tail configurations with the unit length of the repeat being 5.8 kb. several poly(a+) rnas of p. yoelii ranging from 1.6 to 0.3 kb are recognized by the 5.8 kb clone. five additional species of malarial parasites ( ... | 1987 | 3033497 |
| toxoplasma gondii and hammondia hammondi: dna comparison using cloned rrna gene probes. | a mung bean nuclease genomic library of purified dna from tachyzoites of the rh strain of toxoplasma gondii was prepared in the bacteriophage lambda gtll and recombinants containing rrna gene fragments were detected by hybridization with radiolabeled total rna from the closely related coccidian eimeria acervulina. ten recombinants were chosen at random, and five of these were investigated further using probes for the genes of the large and small rrna of plasmodium berghei. an insert (called tg4) ... | 1987 | 3034655 |
| the production of reactive oxygen species in mice infected or immunized with plasmodium berghei. | the capacity of peritoneal exudate cells (pec) obtained from mice infected or immunized with plasmodium berghei to produce reactive oxygen species (ros) and the biological basis of this response was investigated, using luminol-dependent zymosan-triggered chemiluminescence (cl). cl response of pec from infected mice increased at the early stage but was significantly depressed at the later course of the infection. a similar biphasic activity of peroxidase was also observed in pec from infected mic ... | 1987 | 3037470 |
| telomeric motifs are present in a highly repetitive element in the plasmodium berghei genome. | using as probes the subfragments of the telomeric sequence previously cloned by us from plasmodium berghei dna, we identified and cloned a 2.3 kb repeat, largely overlapping the original telomeric insert. restriction mapping indicated that cloned inserts (2.3 kb in length) represented circularly permutated versions of a rather well conserved repeated element, at least in part organized in tandem. the 2.3 kb repeat family with a copy number of about 300 occupies about 4% of the whole genome. the ... | 1987 | 3041211 |
| the antimalarial activity of spathodea campanulata stem bark extract on plasmodium berghei berghei in mice. | | 1988 | 3043485 |
| hepatoprotective activity of kutkin--the iridoid glycoside mixture of picrorhiza kurrooa. | | 1988 | 3049327 |
| variation in expression of antibody-dependent cell-mediated cytotoxicity in rodents with malaria. | antibody-dependent cell-mediated cytotoxicity (adcc) against mouse erythrocytes sensitized with immunoglobulin g was studied in mice with malaria. spleen cells from mice had enhanced cytotoxic activity early in plasmodium berghei infection but not later in the disease. sera from infected animals and partially purified malarial immune complexes inhibited adcc. in addition, adcc was diminished in spleen cells from mice infected with the lethal variant of p. yoelii 17x compared with that in mice in ... | 1988 | 3049377 |
| use of various animal erythrocytes for in vitro cultivation of plasmodium berghei. | | 1988 | 3049412 |
| prevention of experimental cerebral malaria by anticytokine antibodies. interleukin 3 and granulocyte macrophage colony-stimulating factor are intermediates in increased tumor necrosis factor production and macrophage accumulation. | il-3 and granulocyte/macrophage colony stimulating factor (gm-csf) are two cytokines released by activated t lymphocytes that stimulate the growth and differentiation of various hematopoietic cell lines, among which are macrophages. it has been shown that tnf/cachectin, another cytokine that is released mostly by activated macrophages, plays a central role in experimental cerebral malaria (cm), an acute and lethal neurological syndrome induced by plasmodium berghei anka infection in cba mice. si ... | 1988 | 3049913 |
| anemia and anti-erythrocyte antibodies developed after repeated injections of sonicated preparations of plasmodium berghei and babesia rodhaini. | anemia developed in mice after repeated injections of sonicated preparations of plasmodium berghei and babesia rodhaini. anti-erythrocyte antibodies were detected in sera by an enzyme-linked immunosorbent assay and their levels rose as anemia developed. administration of carbon particle suspension to block the mononuclear phagocyte system was effective to inhibit anemia induced by injections of sonicated parasite preparations. sodium dodecyl sulfate-polyacrylamide gel electrophoresis and immunob ... | 1988 | 3051800 |
| the in vitro and in vivo antimalarial activity of some mannich bases derived from 4-[7'-bromo (and chloro)-1',5'-naphthyridin-4'-ylamino]phenol and 4-(7'-trifluoromethylquinolin-4'-ylamino)phenol. | a series of di-mannich bases derived from 4-[7'-bromo (and chloro)-1',5'-naphthyridin-4'-ylamino]phenol and 4-(7'-trifluoromethylquinolin-4'-ylamino)phenol were assayed for activity against chloroquine-sensitive and chloroquine-resistant isolates of cultured plasmodium falciparum using the inhibition of uptake of radiolabelled hypoxanthine. a number of the 4-(7'-trifluoromethylquinolinyl-amino)phenols showed statistically superior activity to chloroquine and amodiaquine against both isolates. an ... | 1988 | 3052332 |
| malaria sporozoites leave behind trails of circumsporozoite protein during gliding motility. | as plasmodium sporozoites undergo gliding motility in vitro, they leave behind trails of circumsporozoite (cs) protein that correspond to their patterns of movement. this light microscopic observation was made using plasmodium berghei sporozoites, a monoclonal antibody (mab h4) directed against the immunodominant repetitive epitope of the cs protein of p. berghei, and an immunogold-silver staining (igss) technique. sporozoites pretreated with agents that inhibit sporozoite motility and invasiven ... | 1988 | 3054075 |
| [effects of large doses of pyronaridine and chloroquine on the ultrastructure of the erythrocytic stages of pyronaridine-resistant line of plasmodium berghei]. | | 1988 | 3055816 |
| [effect of vitamin e on the lipid composition of the erythrocytes of mice and of the malarial parasite plasmodium berghei]. | | 1988 | 3057335 |
| characterization of a specific inhibitor of il2-mediated proliferation from serum of plasmodium berghei infected mice. | serum pools from mice undergoing lethal infection with plasmodium berghei inhibit the growth of an il2-dependent mouse cytotoxic t cell line (ctll). a partially purified preparation of the inhibitory factor specifically inhibited il2-mediated events such as il2-dependent ctll growth and the con a mitogenic response of normal mouse spleen cells. production of and response to il1, as well as growth of myeloma lines, was not affected. administration of the partially purified preparation to normal m ... | 1988 | 3057590 |
| [development of artemether-resistant of line of plasmodium berghei]. | | 1988 | 3057811 |
| [mutagenic effects of n-methyl-n-nitro-n-nitrosoguanidine (mnng) and ethyl methanesulfonate (ems) on chloroquine resistance in plasmodium berghei anka strain]. | | 1988 | 3057812 |
| sex determination and sex differentiation in malaria parasites. | | 1988 | 3058219 |
| screening for antimalarial activity in the genus potomorphe. | ethanolic extracts (cee) of leaves from potomorphe umbellata and potomorphe peltata, popularly said to have antimalarial capacity, were submitted to the 4-day suppressive test in plasmodium berghei-infected mice. the cee of p. umbellata administered either orally (250 and 1250 mg/kg) or subcutaneously (100 and 500 mg/kg) evidenced strong antimalarial activity, significantly reducing the levels of parasitaemia in a dose-dependent manner. on the other hand, the cee of p. peltata was ineffective in ... | 1988 | 3059067 |
| stage-specific proteins of plasmodium berghei-infected red blood cells detected by antibodies of immune mouse serum. | the asynchronously developing malaria parasite plasmodium berghei was synchronized using in vitro cultivation techniques (mons et al. 1985). after the infection of naive mice, preparations of parasitized erythrocytes with a high level of synchronism could be obtained. immunofluorescence and immunoblotting techniques using serum from immunized mice were applied to determine stage-specific immunogenic molecules in the parasitized erythrocyte preparations. these techniques allowed the detection of ... | 1988 | 3060873 |
| [inhibitory effect of artemisinine-sulfadoxine-pyrimethamine combination on the development of drug-resistance in plasmodium berghei]. | | 1988 | 3064550 |
| immunopathology of thrombocytopenia in experimental malaria. | an early thrombocytopenia was observed in cba mice during acute infection with plasmodium berghei. this was associated with an increase in bone marrow megakaryocytes and a reduction of normal syngeneic 111indium-labelled platelet life span. malaria-induced thrombocytopenia was thus considered to be the result of increased peripheral platelet destruction rather than central hypoproduction. the occurrence of thrombocytopenia was modulated by t-cell depletion. indeed, thymectomized, irradiated or a ... | 1988 | 3065215 |
| liposomes as carriers for a human malaria sporozoite vaccine. | | 1988 | 3066667 |
| histochemistry of cerebral lesions in mice infected with plasmodium berghei. | the brains of mice with established symptoms of plasmodium berghei erebral malaria were investigated histochemically and histologically. the activity of mitochondrial, lysosomal, glyco/glycogenolytic, hydrolytic and oxidizing enzymes as well as enzymes of the krebs cycle and the pentose cycle was studied during the course of the infection. for comparison cryostate sections were also stained with haematoxylin and eosin, and according to kluver-barrera. changes in enzyme activity, particularly of ... | 1988 | 3067319 |
| neutral proteases involved in the reinvasion of erythrocytes by plasmodium merozoites. | neutral proteases of plasmodium sp erythrocytic stages were studied by means of a sensitive fluorogenic method and gelatin-sds-page. the substrates gluconoyl-val-leu-gly-lys(or arg)-3-amido-9-ethylcarbazole were selectively hydrolyzed by an endopeptidase from rodent plasmodium berghei (pb) and plasmodium chabaudi (pc) and from human plasmodium falciparum (pf) parasites. these endopeptidases were purified from 100,000-g soluble schizont extract by high pressure liquid chromatography; they have a ... | 1988 | 3067801 |
| [experimental evidence of the possibility of managing the vector capacity of anopheles mosquitoes]. | | 1988 | 3068497 |
| [detection of malarial parasite isoenzymes by cellulose acetate electrophoresis combined with blood concentration in capillaries]. | | 1988 | 3068498 |
| [determination of the optimal method of treating experimental malaria using artemisinine]. | | 1988 | 3068500 |
| phosphorylation of plasmodium berghei derived phosphoproteins associated with the host erythrocyte membrane by the spectrin kinase. | plasmodium berghei derived phosphoproteins are associated with the host erythrocyte membrane. effectors of the phosphorylation reaction regulate the phosphorylation of the p. berghei derived proteins and spectrin in a similar manner. the spectrin kinase also phosphorylates the p. berghei phosphoproteins in a reconstituted reaction at the same site(s) as the endogenously phosphorylated proteins. these results indicate that a host protein kinase may regulate parasite phosphoproteins during malaria ... | 1988 | 3068518 |
| role of immune complexes in cerebral malaria. | to investigate the involvement of immune complexes in the pathogenesis of cerebral malaria, a comparative study between plasmodium berghei infected swiss albino mice and balb/c mice was conducted. rise in parasitemia was found to be same with differences in manifestation of disease and mortality, level of immune complexes and histopathology. increased parasitized red cells with swelling of endothelial cells in the brain capillaries along with increased levels of circulating immune complexes were ... | 1988 | 3071773 |
| [methods of preselecting febrifugal plants from the madascan flora in view of research on their antimalarial activity]. | | 1988 | 3071978 |
| [changes in the ability to produce reactive oxygen by phagocytes from mice infected or immunized with plasmodium berghei]. | | 1988 | 3072115 |
| histamine & kinin system in experimental malaria. | | 1988 | 3072298 |