| a spleen is not necessary to resolve infections with plasmodium yoelii. | the role of the spleen in resistance to infections with nonlethal plasmodium yoelii 17x is dependent upon the genotype of the host. thus, dba/2 (d2) mice infected with p. yoelii 17x were not adversely affected by removal of the spleen, while splenectomized c57bl/6 (b6) or balb/c mice failed to resolve their infections and eventually died. the levels of parasitemia were lower in splenectomized mice compared to intact controls; however, splenectomized mice became as anemic as did spleen-intact con ... | 1991 | 1996740 |
| immunization and protection against malaria during murine pregnancy. | normal and immune mice were evaluated for their ability to resist infection to the rodent malaria parasite, plasmodium yoelii, during pregnancy. parasitemia levels were slightly higher and time-to-death shorter in the nonimmunized pregnant group infected with virulent parasites relative to virgin controls. subinoculation experiments revealed that numerous virulent organisms were present in the placentas of unprotected gravida but were absent from the fetal livers of their conceptuses. it was als ... | 1991 | 2012261 |
| primary structure of the merozoite surface antigen 1 of plasmodium vivax reveals sequences conserved between different plasmodium species. | merozoite surface antigen 1 (msa1) of several species of plasmodia has been shown to be a promising candidate for a vaccine directed against the asexual blood stages of malaria. we report the cloning and characterization of the msa1 gene of the human malaria parasite plasmodium vivax. this gene, which we call pv200, encodes a polypeptide of 1726 amino acids and displays features described for msa1 genes of other species, such as signal peptide and anchoring sequences, conserved cysteine residues ... | 1991 | 2023952 |
| evaluation of merocyanine 540-sensitized photoirradiation as a method for purging malarially infected red cells from blood. | the photosensitizing dye merocyanine 540 (mc 540) was evaluated as a means for purging malarially infected red cells from murine blood using the rodent malarial pathogens, plasmodium yoelii and plasmodium berghei, as models of human malaria. malarially infected red cells bound more mc 540 and were more sensitive to mc 540-sensitized photoirradiation than were noninfected erythroid cells. extracorporeal exposure of infected red cells to the dye and white light prevented the transmission of the di ... | 1991 | 2037797 |
| mitochondria of mammalian plasmodium spp. | highly purified mitochondrial fractions have been isolated from the intraerythrocytic stages of two mammalian plasmodium spp., plasmodium yoelii of rodents and plasmodium falciparum of man. mitochondria of the former parasite are cristate whereas those of the latter are essentially acristate. isolated mitochondria from both parasite species were heterogeneous with respect to size, shape, density of matrix staining and extent of internal structure. respiratory assay, by reduction of exogenous cyt ... | 1991 | 2038500 |
| penetration of the mosquito midgut wall by the ookinetes of plasmodium yoelii nigeriensis. | the penetration route of ookinetes of plasmodium yoelii nigeriensis in the midgut of a mosquito, anopheles omorii, was investigated by electron microscopy. within 15-18 h after an infective blood meal, ookinetes could be seen in the midgut lumen, in the process of entering the midgut wall, or lodged between the basement membrane and the basal lamina. the morphology of the ookinetes and their transformation into early oocysts were found to be similar to those previously reported. ookinetes penetr ... | 1991 | 2047369 |
| inhibitory activity of il-6 on malaria hepatic stages. | addition of recombinant interleukin-6 (il-6) to plasmodium yoelii hepatic cultures resulted in a specific dose-dependent inhibition of parasite development. time course experiments showed that, without any direct effect on free sporozoites, il-6 exerts its action during both the early phase of infection and during the subsequent maturation of the schizonts. elicitation of the oxidative burst appears to be one mechanism by which il-6 interferes with the development of hepatic phase. catalase and ... | 1991 | 2052407 |
| [observation on interleukin-2 in mice infected with plasmodium yoelii]. | c57bl/6j, nih and icr mice were inoculated with nonlethal p. yoelii (by 265 strain) and nih mice which had recovered from primary infection were reinoculated with the same parasite. the parasitemia of the mice was observed and il-2 production by spleen lymphocytes of the mice upon con a or p. yoelii antigen stimulation was detected at different intervals throughout primary infection and reinfection. the il-2 level was measured by the microassay based on incorporation of h-tdr into ctll2. the mai ... | 1991 | 2065455 |
| activities of new acridone alkaloid derivatives against plasmodium yoelii in vitro. | forty-seven new acridone alkaloid derivatives (sa compounds) were tested for antimalarial activity in vitro. at a concentration of 1.0 microgram/ml, six of these inhibited 50% or more of the incorporation of [3h]hypoxanthine into plasmodium yoelii in vitro. the four most potent compounds, sa 3757, sa 3548, sa 3761 and sa 3499, showed 50% inhibitory concentration (ic50) values of 0.023 microgram/ml, 0.03 microgram/ml, 0.053 microgram/ml and 0.15 microgram/ml, respectively. the chemotherapeutic in ... | 1990 | 2080937 |
| reduced antibody response to the repetitive sequence of the plasmodium falciparum circumsporozoite protein in mice infected with plasmodium yoelii blood forms. | the immunogenicity of the carrier-free synthetic peptide, (nanp)40, from the repetitive region of the plasmodium falciparum circumsporozoite (cs) protein was investigated in genetically responder mice (c57bl/6, h-2b) acutely infected with blood forms of the non-lethal murine malaria parasite, p. yoelii. as compared to non-infected mice, p. yoelii-infected c57bl/6 mice produced significantly lower titers of anti-(nanp)40 igg antibodies. this decrease in the anti-(nanp)40 antibody response peaked ... | 1990 | 2082157 |
| generation of a cytotoxic t-lymphocyte response using a salmonella antigen-delivery system. | we have constructed a general-use vector for the cloning and stable expression of foreign genes in the chromosome of attenuated salmonella typhimurium. using this chromosomal expression vector (cev), we expressed the circumsporozoite (cs) gene of the mouse malaria plasmodium yoelii in an aroa s. typhimurium strain. mice immunized with cs-expressing salmonella recombinants mount a cs-specific cytotoxic t-lymphocyte (ctl) response. this is the first demonstration that attenuated salmonella can eli ... | 1990 | 2089224 |
| molecular cloning and sequence analysis of the gene encoding the major merozoite surface antigen of plasmodium chabaudi chabaudi ip-pc1. | the complete nucleotide sequence of the gene encoding the precursor to the major merozoite surface antigens of plasmodium chabaudi chabaudi strain ip-pc1 has been determined. a single open reading frame was detected, that coded for a protein of 199 kda. the encoded protein (p199) contains putative signal and membrane anchor sequences and shows a clustering of cys residues in the last 120 amino acids. incompletely conserved tandem repeat oligopeptides are present at different positions in the mol ... | 1990 | 2090945 |
| genetic restriction of protective immunity to plasmodium yoelii sporozoites. | ten congenic strains of mice were immunized with irradiated sporozoites of plasmodium yoelii. when challenged with viable sporozoites, only two strains had a high proportion of animals which did not develop blood-stage infections. genes both within and outside the h-2 region affected the degree of protection. immunity did not correlate with anti-sporozoite antibody levels. in vivo depletion of cd8+ t cells did not alter immunity in two of three congenic strains, implying the existence of a novel ... | 1990 | 2094575 |
| evaluation of vaccines designed to induce protective cellular immunity against the plasmodium yoelii circumsporozoite protein: vaccinia, pseudorabies, and salmonella transformed with circumsporozoite gene. | in an attempt to induce a protective cytotoxic t-cell mediated immunity against sporozoites of plasmodium yoelii, the gene encoding the p. yoelii circumsporozoite (cs) protein was engineered into three live vectors: vaccinia, attenuated pseudorabies, and attenuated salmonella typhimurium. balb/c mice were immunized with 1-4 doses of 10(8) pfu of the vaccinia construct (ip), 3 doses of 10(5), 10(6) or 10(7) pfu of pseudorabies construct (iv), and 3 doses of 10(9) salmonella transformants (orally) ... | 1990 | 2094576 |
| a malaria sporozoite surface antigen distinct from the circumsporozoite protein. | monoclonal antibody nys4 recognizes a single 140 kda antigen on the surface of plasmodium yoelii sporozoites, an antigen which is distinct from the extensively characterized circumsporozoite (cs) protein. to more thoroughly characterize this additional surface component, a genomic expression library was screened with nys4 and an immunoreactive clone (m4) was obtained which expressed part of the antigen gene. the deduced amino acid sequence of the m4 peptide included two unique repetitive sequenc ... | 1990 | 2094580 |
| localization of cs and non-cs antigens in the sporogonic stages of plasmodium yoelii. | monoclonal antibodies (mabs) and colloidal gold probes were used to localize circumsporozoite (cs) protein and two unrelated polypeptides in developing oocysts and salivary gland sporozoites of the 17x (nl) strain of plasmodium yoelii. mabs nys1, nys2, and nys3 recognized different epitopes of the p. yoelii cs protein and produced similar patterns of immunolabelling on developing oocysts and sporozoites. a small percentage of oocysts contained developing sporoblasts and sporozoites that did not ... | 1990 | 2094581 |
| effect of ketotifen on the ultrastructure of the erythrocytic stages of plasmodium yoelii. | the effect on the morphology of plasmodium yoelii of ketotifen treatment was different from that of chloroquine and other antimalarial drugs. following administration of a low dosage of ketotifen, the parasite first developed a multilamellate pellicular complex which resembled a medullary sheath and then developed vacuoles and cavitations. the development of large multilamellate whorls consisting of a pellicular structure enclosing cytoplasm was the typical change which occurred. | 1990 | 2098914 |
| [study on the exoerythrocytic forms of plasmodium yoelii yoelii in rats and mice]. | sd rats and three strains of mice were infected with plasmodium yoelii yoelii by265 strain by intravenous inoculation of sporozoites via tail vein. liver tissues were taken 42 hours after infection and serial sections were made and stained by colophonium-giemsa method for microscopic examination. the ratio of the average value of major diameter/minor diameter of exoerythrocytic(ee)schizonts of plasmodium yoelii yoelii in rats and mice of icr/jcl, c57bl, km strains was 35.81 +/- 4.56 microns/29.7 ... | 1990 | 2099260 |
| experimental studies on combinations of pyronaridine/primaquine versus chloroquine/primaquine. | the toxicity of combined use of blood schizontocide pyronaridine (pnd) and primaquine (pq) in mice and rats was significantly lower than that of chloroquine (cq) plus primaquine (pq). pnd 1/2 ld50 (ca 600 mg/kg) in combination with pq reduced the toxic action of pq in mice, while cq 1/2 ld50 (ca 300 mg/kg) plus pq produced synergistic toxic effect. in animal models such as plasmodium yoelii sporozoite infection in mice and p. cynomolgi sporozoite infection in rhesus monkeys, the tissue schizonto ... | 1990 | 2127247 |
| antibody formation to low-dose antigen and plasmodium yoelii clearance by offspring of protein-depleted male and female mice. | primary and secondary immune responses to low doses of sheep red blood cells (srbc) were investigated in well-fed first-degree offspring of three groups of protein-deficient mice (pd) and in well-fed first-degree offspring of well-fed mice (nd). the offspring of malnourished males and malnourished females had the highest level of primary anti-srbc antibodies, followed by the offspring of well-fed males and malnourished females, which also had a significantly higher primary anti-srbc antibody tit ... | 1990 | 2134561 |
| structure of a plasmodium yoelii gene-encoded protein homologous to the ca(2+)-atpase of rabbit skeletal muscle sarcoplasmic reticulum. | a cation-transporting atpase gene of plasmodium yoelii was cloned from the parasite genomic library using an oligonucleotide probe derived from a conserved amino acid sequence of the phosphorylation domain of the aspartyl phosphate family of atpases. the complete nucleotide sequence was determined and it predicts a 126,717 mr encoded protein composed of 1115 amino acids. northern blot analysis revealed that the gene is transcribed during the asexual stages of parasite development. the p. yoelii ... | 1990 | 2150071 |
| two soluble antigens of plasmodium falciparum induce tumor necrosis factor release from macrophages. | the production of cytokines such as tumor necrosis factor (tnf) may contribute to the pathology of malaria. we showed previously that crude preparations of heat-stable exoantigens from parasite cultures induce the release of tnf in vitro and in vivo. when separated from the culture medium by affinity chromatography, in which immune immunoglobulin g was used as ligand, the mixture of exoantigens of plasmodium falciparum retained the capacity to induce the secretion of tnf, both by human monocytes ... | 1990 | 2201638 |
| [soluble protein and esterase isozyme analysis of adult female anopheles stephensi after plasmodium yoelii yoelii-infected blood meal]. | in this paper, the system of anopheles stephensi and plasmodium yoelii yoelii was used as animal model. the soluble protein and esterase isozymes of adult female mosquitoes at various times after taking noninfected and plasmodia-infected blood meal were investigated. the result shows that the amount of soluble protein in plasmodia-infected mosquitoes was lower than that in noninfected ones (p less than 0.01); the activity and electrophoretic patterns of est in infected mosquitoes being also diff ... | 1990 | 2208623 |
| [synthesis of 2-methyl-5-substituted phenoxy-primaquine and antimalarials activity]. | in searching for efficient, safe and radically curative agent and causal prophylactics for malaria, seven 2-methyl-5-substituted phenoxy-6-methoxy-8-(1-methyl-4-aminobutylamino)-quinolines (ii1-7) were synthesized and their antimalarial activities were compared with the corresponding 4-methyl substituted derivatives of primaquine. the starting material, 2-nitro-4-methoxy-5-bromo-acetanilide (iii), was prepared from p-methoxy aniline through acetylation, bromination and nitration. iii was then co ... | 1990 | 2239331 |
| experimental transfer of immunity to plasmodium yoelii nigeriensis from adult rats to baby rats. | | 1990 | 2251247 |
| the effects of host diet on plasmodium yoelii nigeriensis. | a comparative study carried out on infected mice to investigate the effect of host diet on plasmodium yoelii nigeriensis showed that concentrations of blood protein, hemoglobin, and erythrocytes began to decrease in infected mice on day 2 after inoculation and reached the lowest levels on day 8. the greatest decrease was among mice fed on protein-rich mouse cubes, whereas the least decrease was among mice fed on cassava meal. inflammation of the spleens and livers of infected mice also was notic ... | 1990 | 2254825 |
| parasite-induced processes for adenosine permeation in mouse erythrocytes infected with the malarial parasite plasmodium yoelii. | in mouse erythrocytes harbouring the malarial parasite plasmodium yoelii, three processes contributed to inward fluxes of adenosine, one of which is attributed to the native nucleoside transporter, because of the inhibitory effects of nitrobenzylthioinosine (nbmpr). new (parasite-induced) permeation processes of low nbmpr-sensitivity were (i) saturable fluxes with preference for the d enantiomer (d-ado) and (ii) apparently unsaturable fluxes that proceeded by a channel-like route without enantio ... | 1990 | 2264834 |
| effect of host-diet inadequacy on the course of infection of plasmodium yoelii nigeriensis. | investigations were conducted into the course of infection of plasmodium yoelli nigeriensis in mice fed on an inadequate diet. it was found that mice fed on a '1/2' diet were able to withstand infection with the parasite better than mice fed on a full diet or a 1/4' diet. the haemoglobin value of mice fed on a full, '1/2' and '1/4' diets dropped by 67.5%, 66.8% and 68.8% respectively, while their packed cell volume dropped by 27.1%, 28.9% and 31.2% respectively. no mortality was recorded for uni ... | 1990 | 2268567 |
| identification of the gene for a plasmodium yoelii rhoptry protein. multiple copies in the parasite genome. | serum from mice hyperimmune to plasmodium yoelii was used to screen a p. yoelii genomic dna library. antibodies selected from hyperimmune serum by lambda gt11 clone j7 or raised against a specific fusion protein or peptide produced a punctate pattern of immunofluorescence on fixed smears of parasitised erythrocytes and immunoprecipitated a 235-kda protein apparently identical to a rhoptry protein previously implicated in red cell invasion. the cloned dna hybridised to at least seven rsai fragmen ... | 1990 | 2270106 |
| irradiated sporozoite vaccine induces cytotoxic t lymphocytes that recognize malaria antigens on the surface of infected hepatocytes. | the observation that protective immunity induced by immunization with radiation attenuated plasmodium berghei and plasmodium yoelii sporozoites is dependent on cd8+ t lymphocytes in some strains of mice led us to speculate that immunization with sporozoites induces cytotoxic t lymphocytes (ctl) that recognize malaria antigens on the surface of malaria-infected hepatocytes. in this report we summarize a series of experiments that confirm this hypothesis. we first showed that when immune mice are ... | 1990 | 2283160 |
| host-parasite interactions and immunity to irradiated sporozoites. | we compare and contrast the results of immunizing mice with irradiated sporozoites of plasmodium berghei and plasmodium yoelii. host genetic control of protective immunity is different in the two rodent malarias. few mouse strains are strongly protected by p. yoelii sporozoites, while all are protected by p. berghei sporozoite immunization. the role of cd8+ t cells in the protective immune response to each of these malarias varies with the strain of mouse. moreover, a single strain will use a cd ... | 1990 | 2283161 |
| [the modelling of the development of plasmodium yoelli yoelli in different vertebrate hosts]. | outbred mice and inbred balb/c mice were used for simulating plasmodium yoelii yoelii (strain 265 by) development. when the infection is initiated by standardized blood cryosamples and in sporozoite infection in various vertebral hosts the infection develops likewise as regard to parasitemia cyclic recurrences, however, the magnitude of parasitemia peaks, time of their occurrence, its stabilization or attenuation are different, which to a great extent determines the period of gametocyte infectiv ... | 1990 | 2290393 |
| plasmodium yoelii nigeriensis circumsporozoite gene structure and its implications for the evolution of the repeat regions. | the circumsporozoite (cs) gene encodes the most immunogenic component of the plasmodial sporozoites. the immunodominant epitope-encoding domain of the cs gene shows sequences that are repeated in tandem. a detailed analysis of the cs repeats of certain closely related malaria parasites (strains of plasmodium cynomolgi, plasmodium knowlesi, and plasmodium vivax) showed that they evolve rapidly yet are well conserved within the gene. we were interested in studying whether the cs repeats of plasmod ... | 1990 | 2290446 |
| plasmodium yoelii: comparative antimalarial activities of dietary fish oils and fish oil concentrates in vitamin e-deficient mice. | feeding vitamin e-deficient diets containing either fish oils such as menhaden, salmon, or anchovy oil or fish oil concentrates based on n-3 ethyl esters or free fatty acids protected mice against plasmodium yoelii as indicated by decreased parasitemia and improved survival. the fish oil concentrates depressed plasma tocopherol levels more strongly in vitamin e-supplemented mice than the menhaden oil. the free fatty acid concentrate appeared to suppress parasitemia in vitamin e-deficient mice be ... | 1990 | 2311714 |
| sequence analysis upstream of the gene encoding the precursor to the major merozoite surface antigens of plasmodium yoelii. | | 1990 | 2320061 |
| effect of plasmodium yoelii infection on gaba metabolism of mouse brain. | plasmodium yoelii infection in albino mice decreased the activity of brain glutamic acid decarboxylase (gad) by about 30 and 48% in crude homogenate and its synaptosomal fraction, respectively. the decrease was evident from 20% parasitemia and remained more or less constant up to 80% parasitemia. the km values of gad in normal and infected animals were 1.2 x 10(-2) and 3.3 x 10(-2) mm, respectively, indicating a decrease in enzyme substrate affinity due to infection. the lowered gad activity ros ... | 1990 | 2332040 |
| the effects of chloroquine on the infectivity of chloroquine-sensitive and -resistant populations of plasmodium yoelii nigeriensis to mosquitoes. | subtherapeutic doses of chloroquine have been reported to enhance infectivity of drug-resistant plasmodium species to their vectors. in this investigation, plasmodium yoelii nigeriensis n67 strain showed enhanced infectivity to mosquitoes when stimulated by chloroquine. both sensitive and resistant clones were derived from the n67 strain by dilution, showing that this strain is polymorphic for the resistant trait. a resistant subline was derived by selection under drug pressure from a chloroquin ... | 1990 | 2362764 |
| role of dna-binding antibodies in kidney pathology associated with murine malaria infections. | we performed a series of studies to examine the sequential development of nephritis during murine malaria infections and to define the role of dna-binding antibodies in the associated pathology. serum levels of these antibodies were assessed throughout acute and chronic malaria infections. increased levels of double-stranded dna- and single-stranded dna-binding antibodies were initially detected in mice infected with plasmodium vinckei or plasmodium yoelii nigeriensis during the middle stages of ... | 1990 | 2365456 |
| antimalarial activity of a combination of 5-fluoroorotate and uridine in mice. | malarial parasites, in contrast to mammalian cells, utilize orotic acid more efficiently than uracil or uridine. recently, chloroquine-susceptible and chloroquine-resistant clones of plasmodium falciparum were shown to be inhibited by 5-fluoroorotate, with a 50% inhibitory concentration of 6 nm in vitro. mammalian cells were far less sensitive to 5-fluoroorotate, particularly in the presence of uridine. in this report, the antimalarial activity of 5-fluoroorotate was tested in vivo. initially, l ... | 1990 | 2386369 |
| cytofluorimetric analysis of dna content in different life stages of plasmodium yoelii. | | 1985 | 2423000 |
| antigen-specific, interleukin 2-propagated t lymphocytes confer resistance to a murine malarial parasite, plasmodium chabaudi adami. | to explore cell-mediated immune mechanisms in host defense against malaria, we utilized a murine model system in which antibody-independent mechanisms of immunity are known to play a major role. splenic t lymphocytes obtained from plasmodium chabaudi adami-immune mice were maintained in vitro by using il 2-containing medium and frequent antigenic stimulation. these il 2-propagated t lymphocytes were characterized for their antigen reactivity, surface phenotype, and ability to confer protection t ... | 1986 | 2423609 |
| characterization of plasmodium yoelii monoclonal antibodies directed against stage-specific sporozoite antigens. | a battery of monoclonal antibodies against plasmodium yoelii sporozoites was produced. five of these (nys1 through nys5) were selected for characterization. all five were positive in the indirect immunofluorescent antibody test with p. yoelii sporozoites; however, each showed a different immunofluorescence pattern. although nys1 (immunoglobulin g3 [igg3]), nys2 (igg3), and nys3 (igm) were positive in the circumsporozoite precipitation test, only nys1 and nys2 were able to neutralize sporozoite i ... | 1987 | 2434426 |
| the 3' portion of the gene for a plasmodium yoelii merozoite surface antigen encodes the epitope recognized by a protective monoclonal antibody. | the 230-kda merozoite antigen of the murine malarial parasite plasmodium yoelii provides a potential model system for the development of a protective erythrocytic stage vaccine. to characterize this antigen at the molecular level, isolated p. yoelii 17xl dna was used to construct a genomic library in the expression vector lambda gt11. a monoclonal antibody, mab 302, which passively protected mice against p. yoelii challenge infection, was used to identify a lambda gt11 recombinant clone encoding ... | 1988 | 2448778 |
| molecular clones of alpha-tubulin genes of plasmodium yoelii reveal an unusual feature of the carboxy terminus. | by using a trypanosoma brucei alpha-tubulin cdna probe under reduced stringency hybridization conditions, we have isolated two genomic clones that constitute portions of alpha-tubulin genes of the rodent malarial parasite plasmodium yoelii. p. yoelii has two alpha-tubulin genes, the 3' portions of which were present in the two clones, py alpha t1 and py alpha t2, containing 1.3 kb and 6.6 kb ecori fragments respectively. the 1358 bp py alpha t1 clone was completely sequenced and found to contain ... | 1988 | 2459618 |
| plasmodium yoelii: characterization of a protective idiotype during malarial infection in mice. | we have previously identified and characterized a monoclonal antibody (mcab 302) with potent passive protective activity in mice infected with plasmodium yoelii, a murine malarial parasite which depends on antibodies for resolution. to further study the appearance and regulation of this antibody during infection, we prepared syngeneic monoclonal antibodies specific for idiotopes present on mcab 302. three hybridomas were established which synthesized antibodies that bound only to the homologous ... | 1988 | 2461316 |
| [effect of nitroquine (cl-679) in vitro on incorporation of [3h]hypoxanthine into dna and rna of plasmodium yoelii]. | | 1988 | 2461638 |
| a protective monoclonal antibody recognizes a variant-specific epitope in the precursor of the major merozoite surface antigen of the rodent malarial parasite plasmodium yoelii. | the precursor of the major merozoite surface ag (pmmsa) represents one of the principal molecules of the erythrocytic stages of malarial parasites. previously we reported that mab 302 recognizing the 230-kda pmmsa of plasmodium yoelii provided passive protection to mice challenged with this parasite. we now report that the protective capacity of mab 302 is variant specific, affording protection against infection with only three of five p. yoelii lines. immunoprecipitation analyses of their pmmsa ... | 1989 | 2467942 |
| cloning of plasmodium yoelii genes expressing three different sporozoite-specific antigens. | genomic dna isolated from plasmodium yoelii (strain #17xnl) was prepared by partial digestion and cloned in escherichia coli tb-1 with puc18 plasmid. antigen-producing recombinants were detected by a battery of monoclonal antibodies against antigens of the sporozoite stages. four clones producing stage-specific sporozoite antigens were identified. one produced p. yoelii circumsporozoite protein, and three produced other p. yoelii sporozoite antigens. | 1989 | 2472543 |
| mechanisms of splenic control of murine malaria: cellular reactions of the spleen in lethal (strain 17xl) plasmodium yoelii malaria in balb/c mice, and the consequences of pre-infective splenectomy. | the splenic response in lethal 17xl plasmodium yoelii murine malaria is vigorous, displaying marked phagocytosis, erythropoiesis, lymphopoiesis, plasmacytopoiesis, and, from day 3 of infection, increasing levels of parasitized erythrocytes. there is also a pronounced response of newly characterized fibroblastic stromal cells which branch and fuse with one another, forming extensive, complex, irregular, syncytial membranous sheets which provide a variety of barriers. hence, i term these barrier c ... | 1989 | 2476037 |
| a protective monoclonal antibody recognizes an epitope in the carboxyl-terminal cysteine-rich domain in the precursor of the major merozoite surface antigen of the rodent malarial parasite, plasmodium yoelii. | the 195-kda major merozoite surface antigen of plasmodium falciparum (pf pmmsa) is a potential candidate for the development of a blood-stage malarial vaccine. we have focused on an analogous 230-kda ag of the rodent malarial parasite, plasmodium yoelii, in an effort to study this protein in an experimental model system. previously we reported the cloning and sequencing of a 2.1-kb portion of the gene encoding the carboxyl-terminal 77 kda of the py pmmsa. this region contained the b cell epitope ... | 1989 | 2477452 |
| nile blue as a stain for exoerythrocytic forms of plasmodium yoelii. | | 1989 | 2481349 |
| role of ifn-gamma in lethal and nonlethal malaria in susceptible and resistant murine hosts. | ifn-gamma plays an important role in host defense against microbial disease. here, we studied the role of ifn-gamma in lethal and nonlethal murine malaria. administration of recombinant murine ifn-gamma resulted in a dose-dependent protection of sw, balb/cbyj, and cba/j mice from the lethal variant of plasmodium yoelii 17x (pyl) but had little effect on the course of the nonlethal variant of this parasite (pynl). administration of recombinant ifn-gamma also resulted in the activation of peritone ... | 1989 | 2506274 |
| genetic control of immunity to plasmodium yoelii sporozoites. | using a rodent malaria system, we have shown that protective immunity to the preerythrocytic stages of malaria is genetically controlled by mhc and non-mhc genes. ten congenic strains of mice were immunized with irradiated sporozoites of plasmodium yoelii. when challenged with viable sporozoites, only two strains had a high proportion of animals that did not develop blood stage infections. immunity did not correlate with antisporozoite antibody levels. two protective mechanisms exist determined ... | 1989 | 2512354 |
| experimental infections of plasmodium yoelii nigeriensis in mice and rats, and hosts' reactions. | in investigations into the course of infection of plasmodium yoelii nigeriensis in rats and mice, it was found that adult mice, baby mice and baby rats were susceptible to the infection, while adult rats were totally refractive. the infection was rapidly fatal in baby and adult mice but was maintained with a low parasitaemia and tolerated by baby rats until the animals were 7 weeks old, after which they eradicated the infection totally. although the adult rats did not exhibit any parasitaemia, t ... | 1989 | 2545080 |
| sequences similar to genes for two mitochondrial proteins and portions of ribosomal rna in tandemly arrayed 6-kilobase-pair dna of a malarial parasite. | erythrocytic stages of mammalian malarial parasites contain acristate mitochondria whose functions are not well understood. moreover, little is known about the genome of these organelles. we have previously reported that all species of malarial parasites examined contain highly conserved, tandemly arrayed dna with a unit length of about 6.0 kb that is transcribed into discrete rna molecules in erythrocytic stages. we now report the complete dna sequence of the 5984-bp repeating unit of plasmodiu ... | 1989 | 2549417 |
| the effect of pentostam and cimetidine on the development of leishmaniasis (leishmania mexicana amazonensis) and concomitant malaria (plasmodium yoelii). | balb/c mice were infected with leishmania mexicana amazonensis and/or plasmodium yoelii in order to determine the impact of multiple parasitic infection on the efficacy of chemotherapeutic agents. uninfected, p. yoelii-infected, l.m. amazonensis-infected, and l.m. amazonensis and p. yoelii-infected mice were inoculated with cimetidine (80 mg kg-1 day-1) or pentostam (200 mg kg-1 day-1) once a day for an initial 20-day period, and once a week thereafter. leishmania mexicana amazonensis lesion dev ... | 1989 | 2557804 |
| rapid clearance of plasmodium yoelii-infected erythrocytes after exposure to the ionophore a23187. | 1. the effects of ca2+ and the calcium ionophore a23187 on the intraerythrocytic development of the asexual forms of plasmodium yoelii were examined. 2. erythrocyte-free parasites obtained by saponin lysis of infected cells remained viable after exposure to 1 mm ca2+. 3. a23187 inhibited the growth of p. yoelii and the inhibition was augmented by ca2+ in cells infected with parasites at young stage of development. 4. a23187-treated infected cells disappeared from the circulation shortly after in ... | 1989 | 2567656 |
| [ultrastructural study on effect of primaquine on sporogonic stage of plasmodium yoelii nigeriensis]. | ultrastructural changes of oocysts and sporozoites of plasmodium yoelii nigeriensis was observed. anopheles stephensi were allowed to obtain blood meal from the mice which had been administered with primaquine diphosphate at different doses and times. mosquitoes were directed and prepared 6-13 d following infection. electron microscopy showed that the development and morphology of a number of oocysts and sporozoites in infected mosquitoes after treatment became abnormal. the cytoplasma of the oo ... | 1989 | 2610001 |
| effect of irradiation on plasmodium sporozoites depends on the species of hepatocyte infected. | the use of models such as rodents immunized with irradiated rodent malaria sporozoites can be helpful in defining the hepatic antigens which elicit a protective response. after "normal" penetration into the hepatocyte, and "normal" transformation, into trophozoites, irradiated sporozoites are known to begin development, but abort after a period of time that depends on the dose of radiation received. experiments performed with cultured rat, mouse and thamnomys gazellae hepatocytes infected with p ... | 1989 | 2623430 |
| in vitro and in vivo activities of atalaphillinine and related acridone alkaloids against rodent malaria. | thirty acridone alkaloids obtained from citrus, glycosmis, or severinia plants (members of the family rutaceae) were tested for their antimalarial activities in vitro and in vivo. at a concentration of 10 micrograms/ml in vitro, seven of these alkaloids suppressed 90% or more of plasmodium yoelii, which causes malaria in rodents. atalaphillinine, when injected intraperitoneally in a daily dose of 50 mg/kg for 3 days into mice infected with 10(7) erythrocytes parasitized with plasmodium berghei o ... | 1989 | 2653215 |
| soluble malarial antigens are toxic and induce the production of tumour necrosis factor in vivo. | heat-stable soluble products of rodent malarial parasites induce activated peritoneal macrophages to secrete tumour necrosis factor (tnf) in vitro. since heat-stable parasite antigens are known to be present in the circulation of patients with malaria and it has been suggested that much of the pathology of malaria is due to tnf, we investigated the ability of such antigens to induce the production of tnf in vivo and to be toxic to mice. injection of antigens obtained from plasmodium yoelii or fr ... | 1989 | 2654012 |
| immunotoxicity of the semiconductor gallium arsenide in female b6c3f1 mice. | the effects of gallium arsenide (gaas) exposure on immunocompetence of b6c3f1 female mice were investigated. gaas was administered as a single intratracheal instillation at doses of 50, 100, and 200 mg/kg. fourteen days after exposure, various cellular and humoral immune parameters were assessed. gaas exposure increased spleen cellularity in a dose-dependent manner. however, the percentages of thy 1.2 positive and ig positive cells were decreased and that of f4/80 positive cells was increased do ... | 1989 | 2695379 |
| 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 |
| igg3 is the major source of cryoglobulins in mice. | a total of 20 of 23 igg3 mab derived from unmanipulated autoimmune mrl/mpj-lpr/lpr mice was shown to generate cryoglobulins which were composed exclusively of igg3. although three igg3 mab failed to develop cryoglobulins, they were able to bind nonspecifically to any igg3 molecules as efficiently as cryoprecipitable igg did. the direct role of the gamma 3 constant region for the generation of cryoglobulins was demonstrated by the following findings: 1) the cryoglobulin activity was independent o ... | 1989 | 2738401 |
| dual action of anti-sporozoite antibodies in vitro. | with the use of a double staining technique that permits localization of the sporozoite during the process of entering a host cell, we studied the biologic effects of three mab directed against determinants contained in the circumsporozoite of plasmodium yoelii. these mab, which included one igm and two igg3, were studied in primary cultures of rodent hepatocytes inoculated with sporozoites of p. yoelii. these results confirm previous reports of the extended action of antibodies on plasmodium fa ... | 1989 | 2745980 |
| induction of nucleoside transport sites into the host cell membrane of babesia bovis infected erythrocytes. | normal bovine erythrocytes have negligible ability to transport adenosine and related nucleosides across their cell membrane. however, infection with the intraerythrocytic parasite babesia bovis was found to induce a nucleoside permeation site into the host cell membrane. transport experiments over periods of up to 30 s determined that the transport rate of 1 microm adenosine into the infected cell was 1.72 +/- 1.2 pmol incorporated (microliter cell water)-1s-1, a rate three times higher than fo ... | 1989 | 2747745 |
| qinghaosu, dietary vitamin e, selenium, and cod-liver oil: effect on the susceptibility of mice to the malarial parasite plasmodium yoelii. | young female mice were fed torula-yeast-based diets deficient in vitamin e or selenium or supplemented with cod-liver oil to determine the effect of host antioxidant status on the therapeutic efficacy of the chinese traditional antimalarial drug qinghaosu (qhs), a sesquiterpene endoperoxide. vitamin e deficiency enhanced the antimalarial action of qhs against plasmodium yoelii, both in terms of decreased parasitemia and improved survival but se deficiency did not. a vitamin e-deficient diet cont ... | 1989 | 2756922 |
| [scanning electron microscopic observations of ookinete formation of plasmodium yoelii yoelii in vitro]. | the ookinete formation and mature ookinete of plasmodium yoelii yoelii were described. during the development from zygote to ookinete, at first a finger-shaped or a stick-shaped projection protruded from one side of zygote. the anterior end of the projection assumed a truncated cone shape. following enlargement of the projection, the body of zygote gradually wrinkled and shrank and became smaller. an annular structure developed between the newly formed ookinete and the remaining body of zygote, ... | 1989 | 2766499 |
| transport processes of 2-deoxy-d-glucose in erythrocytes infected with plasmodium yoelii, a rodent malaria parasite. | the transport processes of d-glucose in plasmodium yoelii-infected mouse erythrocytes were investigated using 2-deoxy-d-glucose (2dog), a non-metabolizable analogue of d-glucose. infected cells showed an increase in the uptake of 2dog compared to uninfected controls, and an effect which was more prominent in cells with mature-stage parasites. kinetic studies measuring the initial rates of 2dog uptake revealed two components in infected cells with late trophozoite and schizont-stage parasites: a ... | 1989 | 2771446 |
| antimalarial efficacy of arteether against multiple drug resistant strain of plasmodium yoelii nigeriensis. | new quick-acting blood schizontocides are needed to contain the spread of multiple drug resistant strains of p. falciparum and for the treatment of the cerebral malaria cases. a multiple drug resistant strain of p. yoelii nigeriensis resistant to mefloquine (128 mg/kg x 6 days), quinine (300 mg/kg x 7 days) and chloroquine (64 mg/kg x 8 days) was found to be completely susceptible to arteether (a 30:70 mixture of alpha and beta enantiomers) and a dose of 5 mg/kg x 3 days by i.m. route was curati ... | 1989 | 2771860 |
| mechanisms of splenic control of murine malaria: tissue culture studies of the erythropoietic interplay of spleen, bone marrow, and blood in lethal (strain 17xl) plasmodium yoelii malaria in balb/c mice. | this work characterizes the erythropoietic interplay of the spleen, blood, and bone marrow in a lethal murine malaria, strain 17xl p. yoelii. this malaria runs a fulminant 7 day course in balb/c/byj mice, marked by high levels of parasitized reticulocytes with death likely due to anemia. we have quantitated the levels of burst forming units-erythroid (bfu-e), the early, niche-seeking, largely erythropoietin-unresponsive erythropoietic precursors, and of colony forming units-erythroid (cfu-e), th ... | 1989 | 2774062 |
| cloning and analysis of the gene encoding the 230-kilodalton merozoite surface antigen of plasmodium yoelii. | the complete nucleotide sequence of the gene for the 230-kda precursor to the major merozoite surface antigens (pmmsa) of plasmodium yoelii ym has been determined. a single open reading frame of 5316 bp encodes a protein of calculated molecular mass 197,000. the deduced amino acid sequence contains potential signal peptide and membrane anchor sequences of 19 and 18 residues, respectively, and a region of six tandemly repeated tetrapeptides, gly-ala-val-pro. comparison with the 195-kda plasmodium ... | 1989 | 2797063 |
| precursor to the major merozoite surface antigen of plasmodium yoelii: cloning and sequencing of the middle 1.9-kb region. | | 1989 | 2797064 |
| studies on the mechanism of anemia in rodent malaria. | the underlying cause of anemia is one of the problems to be solved in malaria research. many factors are involved in reducing the quantity of uninfected red blood cells (rbc) in addition to those infected rbc destroyed by malaria parasites. in the plasmodium yoelii (p.y.)-mouse model, the amount of [51cr]-labelled normal mouse rbc destroyed in peripheral blood as well as the quantity phagocytized by spleen cells during acute and chronic infection in vivo is reported in this paper. our results sh ... | 1989 | 2798398 |
| activation of liver macrophages in murine malaria is enhanced by vaccination. | during blood-stage infection of mice with a lethal variant of plasmodium yoelii, cells in both spleen and liver became activated to reach a peak at day 5. in mice protected by vaccination, activation was accelerated after infection. the most striking difference observed was in the 10-fold greater yield of infiltrating cells, including macrophages, obtained from the liver just before the mice recovered. their capacity to give an oxidative burst and their cytotoxic activity against tumour cells wa ... | 1987 | 2830070 |
| effect of stress conditions on the course of trophozoite-induced plasmodium yoelii nigeriensis in mice recently cured of a previous infection. | the effect of stress conditions on the course of trophozoite-induced plasmodium yoelii nigeriensis in mice recently treated for a previous infection was studied. it was found that when the mice were infected with up to 5943 parasites within 6 days of treating a previous infection, no patent infection was recorded. however, an inoculum of 7924 parasites induced parasitaemia, with a long period of prepatency and a short course of infection before the parasites died out. none of the mice re-infecte ... | 1988 | 2843024 |
| t-cell-mediated immune response in murine malaria: differential effects of antigen-specific lyt t-cell subsets in recovery from plasmodium yoelii infection in normal and t-cell-deficient mice. | for analysis of the role of immune t cells in protective immunity against murine malaria, plasmodium yoelii-immune lyt t-cell subsets were functionally characterized in vitro and in vivo. selected lyt2- and lyt2+ t cells from p. yoelii-immune c57bl/10 mice differed in their capability to proliferate in response to p. yoelii antigen in vitro. only the lyt2- t-cell population produced t-cell growth factor upon restimulation, and none of the selected t-cell subsets produced detectable amounts of ma ... | 1985 | 2857683 |
| 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 |
| vaccination with a purified blood-stage malaria antigen in mice: correlation of protection with t cell mediated immunity. | a purified 230,000 mol wt protein antigen from the lethal mouse malaria parasite plasmodium yoelii ym which had previously been shown to be highly effective as a vaccine, was tested for its ability to stimulate specific helper t cells and t cells responsible for delayed hypersensitivity. strong stimulation was found in both assays, but larger doses were required for delayed hypersensitivity, correlating well with the requirements for protection. it is suggested that t stimulation may be a requir ... | 1985 | 2933196 |
| rapid parasite multiplication rate, rather than immunosuppression, causes the death of mice infected with virulent plasmodium yoelii. | protective immunity against a lethal malaria challenge infection was passively transferred to naive recipient mice with spleen cells from donor mice bearing a lethal infection with the virulent ym strain of plasmodium yoelii. successful transfer of protection was contingent upon the elimination of residual, viable parasites from donor spleen cell suspensions prior to the infusion of cells. passive transfer experiments failed to detect suppressor cells in the spleens of lethally infected mice bec ... | 1987 | 2948918 |
| immunization of mice against blood-stage plasmodium yoelii malaria with isoelectrically focused antigens and correlation of immunity with t-cell priming in vivo. | mice were immunized with lethal plasmodium yoelii blood-stage malaria antigens that had been fractionated by isoelectric focusing using a variety of ampholines over the range ph 3 to 10. fractions were tested for their ability to protect against live challenge and to prime for parasite-specific t-cell help. both activities exhibited three major peaks in the ph regions 4.5, 6.5, and 8, the ph 4.5 peak being the most consistently protective. there was a significant correlation between protection a ... | 1988 | 2961703 |
| oxygen radical release by adherent cell populations during the initial stages of a lethal rodent malarial infection. | a series of experiments was carried out to assess the levels of reactive oxygen intermediates (roi) released by macrophages and monocytes during an acute malarial infection, and to consider the importance of oxidant-induced parasite killing in host protection. adherent cell populations were removed from the peritoneum and spleen of balb/c and b10/d2/n mice between days 0-5 of a plasmodium yoelii nigeriensis infection. these cell populations were quantified, characterized and their roi-releasing ... | 1985 | 3000927 |
| macrophage plasma membrane and secretory properties in murine malaria. effects of plasmodium yoelii blood-stage infection on macrophages in liver, spleen, and blood. | we have studied the effect of infection with the blood-stage of plasmodium yoelii 17x, a nonlethal parasite, on plasma membrane antigens, receptors, and secretory properties of macrophages (m phi) in murine liver, spleen, and blood. mab f4/80 (m phi specific), f7/4 (a marker for immature and immunologically activated m phi, as well as neutrophils), and mac-1, which binds to the type 3 complement receptor, were used to measure the distribution and total content of antigens in situ and to assay su ... | 1986 | 3001215 |
| 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 |
| changes in oxidative burst capacity during murine malaria and the effect of vaccination. | adherent spleen and liver cells from mice infected with plasmodium yoelii 17x or p. chabaudi as were tested for production of reactive oxygen intermediates to measure their state of activation. phorbol myristate acetate (pma) was used to trigger the respiratory burst and production of superoxide anions was measured by the reduction of nitroblue tetrazolium. spleen cells from mice infected with p. chabaudi showed an early increase in oxidative activity on day 3, and when the oxidative capacity of ... | 1986 | 3026701 |
| 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 |
| iron chelators: in vitro inhibitory effect on the liver stage of rodent and human malaria. | the activity of desferrioxamine (desferal) and desferrithiocin (a newly developed oral iron chelator) was evaluated against the liver stage of plasmodium yoelii and p. falciparum in the rodent and the human hepatocyte in vitro culture system. the two iron chelators were found to inhibit the liver schizogony of both the rodent and the human plasmodium species at concentrations achievable in vivo. p. falciparum proved to be more sensitive (ic 95% below 20 micromol/l than p. yoelii (ic 95% 50-100 m ... | 1988 | 3052118 |
| [intravector anti-plasmodium activity of a pyrethrinoid: deltamethrin]. | in vitro tests, deltamethrin reduced the parasitemic index of plasmodium falciparum on human red blood corpuscles. in vivo tests, at sublethal doses, deltamethrin limited the development of the sporogonic cycle of plasmodium yoelii yoelii in anopheles stephensi. this novel type of antiplasmodic activity involve an intravectorial route and gives an explanation about surprising antimalaria effects observed several months after treatment. | 1986 | 3096513 |
| structure of the gene encoding the circumsporozoite protein of plasmodium yoelii. a rodent model for examining antimalarial sporozoite vaccines. | the gene encoding the circumsporozoite protein (csp) from the rodent malaria parasite, plasmodium yoelii, has been cloned and the nucleotide sequence has been determined. the gene encodes a protein of 367 amino acids as deduced from the nucleotide sequence. this gene is structurally similar to other plasmodium spp. csp genes in that it contains putative hydrophobic signal and anchor sequences at the nh2 and cooh termini, respectively, two small regions (regions i and ii) that are conserved in al ... | 1987 | 3102479 |
| cellular subsets involved in cell-mediated immunity to murine plasmodium yoelii 17x malaria. | cell mediated immunity to nonlethal plasmodium yoelli 17x (py17x-nl) was examined in the cba/caj mouse by adoptive transfer of sensitized t lymphocyte subsets. in intact mice, py17x-nl causes a self-limiting infection with parasitemia levels ranging from 10 to 25% of total red blood cells. upon recovery, mice are refractory to subsequent challenge with the homologous parasite. in t cell-depleted mice, py17x-nl infections are extremely virulent and result in death of the host after parasitemia le ... | 1987 | 3102605 |
| histidine-rich protein in rodent malaria. | mouse red blood cells (rbcs) infected with the malaria parasite plasmodium yoelii nigeriensis were shown to synthesize a histidine-rich protein (his-rp) in vitro. the existence of this protein was demonstrated by comparing fluorograms of infected red blood cells (irbcs) labelled with either [14c]histidine or [14c]leucine. the molecular weight of this his-rp was estimated to be 43,500, which compares well with the values reported for the avian parasite p. lophurae (45,000) and for the human paras ... | 1987 | 3111551 |
| recombinant gamma interferon is a potent adjuvant for a malaria vaccine in mice. | mice were protected against lethal plasmodium yoelii malaria by vaccination with a triton x-100 lysate of whole parasitized erythrocytes. for full effectiveness this vaccine required an adjuvant, and we have found that recombinant gamma-interferon has strong adjuvanticity in this model when given either intraperitoneally or subcutaneously. specific immune responses that were enhanced included antibody, t cell help, and delayed hypersensitivity. | 1987 | 3113784 |
| igh-c allotype-linked control of anti-dna production and clonotype expression in mice infected with plasmodium yoelii. | the infection of nonlethal strain of plasmodium yoelii induces the formation of igg anti-dna antibodies as a result of polyclonal b cell activation. by using various nonautoimmune strains of mice including h-2 or igh congenic or recombinant mice, the levels and clonotypes of anti-dna antibodies elicited by the malaria infection were analyzed in relation to the expression of the mhc or igh gene. our results showed there were little, if any, differences in serum anti-dna levels and their clonotype ... | 1988 | 3139752 |
| heterologous synergistic interactions in concurrent experimental infection in the mouse with schistosoma mansoni, echinostoma revolutum, plasmodium yoelii, babesia microti, and trypanosoma brucei. | primary infections with plasmodium yoelii and echinostoma revolutum in the mouse induced a significant increase in the heterologous schistosoma mansoni challenge worm establishment, whereas s. mansoni worm establishment remained unaffected by primary infections with trypanosoma brucei and babesia microti. concurrent infection in the mouse with p. yoelii or t. brucei, but not with b. microti, blocked the resistance to homologous e. revolutum challenge infection, and primary p. yoelii and t. bruce ... | 1988 | 3143108 |
| [a simple method for isolating plasmodium yoelii]. | | 1987 | 3155375 |
| [effects of pyrimethamine on the oocyst formation of plasmodium yoelii yoelii]. | | 1988 | 3180361 |
| [studies on the effective components in protective sera against plasmodium yoelii infections in mice]. | | 1988 | 3180365 |
| changes in the spontaneous flight activity of the mosquito anopheles stephensi by parasitization with the rodent malaria plasmodium yoelii. | an acoustic actograph was used to monitor for 17 days after infection the spontaneous flight activity of the mosquito anopheles stephensi parasitized with the rodent malaria plasmodium yoelii. activity fell to approximately two-thirds of control levels at about day 10 post-infection--when oocysts were reaching maximum size and starting to rupture (mean number of oocysts = 92)--and thereafter remained at this reduced level. the circadian activity pattern was not affected by the parasitism. | 1988 | 3200604 |
| interactions between malaria (plasmodium yoelii) and leishmaniasis (leishmania mexicana amazonensis): effect of concomitant infection on host activity, host body temperature, and vector engorgement success. | | 1988 | 3204626 |
| interactions between plasmodium yoelii and leishmania mexicana amazonensis in leishmania resistant c57b1/6 mice. | we examined the effect of concurrent infection with plasmodium yoelii and leishmania mexicana amazonensis on the course of each disease in leishmania resistant c57bl/6 mice. p. yoelii parasitemia was greatly enhanced when l. m. amazonensis was inoculated 2 days, 3 weeks, or 12 weeks prior to the malaria. lesions due to l. m. amazonensis were enhanced in mice concomitantly infected with p. yoelii compared to mice infected with l. m. amazonensis only. metastatic l. m. amazonensis lesions developed ... | 1988 | 3207174 |