| kinetics of lymphocyte subsets from peripheral blood during a plasmodium falciparum malaria attack. | variations of lymphocyte subsets were followed longitudinally in 16 patients during an acute falciparum malaria attack. before treatment, lymphocyte numbers were highly reduced, but the subset distribution was similar to that of healthy individuals. after parasite clearance, lymphocyte counts were normalized and the subset distribution was unchanged. this led to a normalization of all the absolute counts of lymphocyte subsets, except cd8+. the fast normalization of lymphocyte counts suggests tha ... | 1992 | 1458676 |
| the in vitro and in vivo antimalarial activity of some mannich bases derived from 4-(7'-trifluoromethyl-1',5'-naphthyridin-4'-ylamino)phenol, 2-(7'-trifluoromethyl-quinolin-4'-ylamino)phenol, and 4'-chloro-5-(7''-trifluoromethylquinolin-4''-ylamino)biphenyl -2-ols. | a series of di-mannich base derivatives (4 and 5) from 4-(7'-trifluoromethyl-1',5'-naphthyridin-4'-ylamino)phenol and 2-(7'-trifluoromethylquinolin-4'-ylamino)phenol, respectively, and mono-mannich base derivatives (6) from 4'-chloro-5-(7''-trifluoromethylquinolin-4''- ylamino)biphenyl-2-ol were assayed for activity against the chloroquine-sensitive (fcq-27) isolate of cultured plasmodium falciparum using the inhibition of uptake of radiolabelled hypoxanthine. all seven di-mannich base derivativ ... | 1992 | 1463352 |
| seasonal abundance and biting behaviour of anopheles punctulatus and an. koliensis in malaita province, solomon islands, and a trial of permethrin impregnated bednets against malaria transmission. | seasonal abundance of the malaria vectors anopheles punctulatus dönitz and an.koliensis owen in bilimanu, an isolated inland village with forty-two houses in malaita province of the solomon islands, was monitored over 28 months by means of all-night landing/biting catches at one site during june 1985 to september 1987. totals of 1250 an.punctulatus and 141 an.koliensis were collected, the latter being the largest number of this species ever caught at any locality in the solomons. bednets impregn ... | 1992 | 1463904 |
| [stability of p. falciparum resistance to chloroquine between 1987 and 1989 in mounana, gabon]. | between 1987 and 1989 the trend in the chloroquine resistance of plasmodium falciparum in the mining town of mounana in south-eastern gabon was studied in vivo and in vitro in 58 and 158 subjects, respectively, aged from 1 to 15 years. the tests used were a simplified variant of the standard who 7-day test for the in vivo study and the isotopic semi-microtest of chemosensitivity for the in vitro study. the health situation in 1989 showed no change from the 1987 situation, but an increase in febr ... | 1992 | 1464148 |
| parvovirus b19 infection during acute plasmodium falciparum malaria. | | 1992 | 1464364 |
| plasmodium vivax and p. falciparum epidemiology in gambella, south-west ethiopia. | plasmodium vivax and p. falciparum epidemiology were studied for parasitological and entomological samples collected during the period 1989 and 1990, respectively, from gambella, south west ethiopia. of the total population examined (n = 1091), 147 (13.5%) were found to be positive for malaria parasites. prevalence rates among males and females were 13.8% and 13.1%, respectively. differences in the prevalence rates of malaria in the eleven villages were observed, the highest (33.3%) being in uku ... | 1992 | 1470839 |
| susceptibility of african isolates of plasmodium falciparum to artemisinin (qinghaosu). | we studied in vitro susceptibility of 79 african strains of plasmodium falciparum to artemisinin, chloroquine, quinine, mefloquine and halofantrine and the potential cross-resistance among the drugs. most strains presented an 50% inhibitory concentration (ic50) of artemisinin below 26 nmol/liter. a positive correlation between ic50s of artemisinin and those of quinine, mefloquine and halofantrine was observed. cross resistance between artemisinin and other antimalarials may limit its use as a re ... | 1992 | 1470842 |
| trafficking of malarial proteins to the host cell cytoplasm and erythrocyte surface membrane involves multiple pathways. | during the asexual stage of malaria infection, the intracellular parasite exports membranes into the erythrocyte cytoplasm and lipids and proteins to the host cell membrane, essentially "transforming" the erythrocyte. to investigate lipid and protein trafficking pathways within plasmodium falciparum-infected erythrocytes, synchronous cultures are temporally analyzed by confocal fluorescence imaging microscopy for the production, location and morphology of exported membranes (vesicles) and parasi ... | 1992 | 1469045 |
| [is the in vivo test for resistance to antimalarial agents in malaria as defined by the who valid?]. | | 1992 | 1469944 |
| treatment of patients with recrudescent falciparum malaria with a sequential combination of artesunate and mefloquine. | a sequential combination of artesunate followed by mefloquine was evaluated prospectively in 24 patients with acute recrudescent falciparum malaria. the sequential combination was used to minimize possible side effects and to take advantage of the ability of artesunate to rapidly clear parasitemia and the prolonged effect of mefloquine to clear residual parasites. all patients had experienced one or more treatment failures with one or more courses of the following drugs (administered alone or in ... | 1992 | 1471736 |
| low immunogenicity of a plasmodium vivax circumsporozoite protein epitope bound by a protective monoclonal antibody. | the repeat region of the plasmodium vivax circumsporozoite (cs) protein contains 20 copies of the nine-amino acid sequence dra a/d gqpag. a monoclonal antibody that passively protects monkeys against sporozoite challenge recognizes a four-amino acid linear sequence agdr included within this nonamer, but when monkeys were immunized with a vaccine, ns1(81)v20, which contains 20 copies of the nonamer, they failed to produce antibodies to agdr. to determine if natural exposure to sporozoites induces ... | 1992 | 1471743 |
| infant and child mortality and malaria in the congo. the trend in the suburbs of brazzaville between 1981 and 1988. | this survey was carried out on a cohort of children born between 1st january 1981 and 30th june 1987 in the maternity department of the hospital in linzolo, a village situated 25 km south-west of brazzaville, the capital of the congo. the mothers of the children resided in the suburbs of brazzaville at the time of delivery. in this region, the rate of transmission of plasmodium falciparum malaria is high without marked seasonable variations. the mothers and children were traced in the second qua ... | 1992 | 1470838 |
| mosquito size and multiple transmission of avian malaria in the laboratory. | probing mosquitoes salivate before ingesting blood, and malaria sporozoites are transmitted during this phase of feeding. large and small aedes aegypti infected with plasmodium gallinaceum were allowed to probe briefly on a series of 3 naive chicks. large mosquitoes were more infective overall, but there was no difference in the ability of either size class to infect the first host. large mosquitoes were more likely than small mosquitoes to infect more than one host during serial feeding. | 1992 | 1474384 |
| sporozoite transmission by anopheles freeborni and anopheles gambiae experimentally infected with plasmodium falciparum. | a micro-membrane feeding technique was used to evaluate sporozoite transmission for anopheles freeborni and an. gambiae experimentally infected with plasmodium falciparum. from cohorts of infected mosquitoes with equivalent sporozoite loads, 75.9% of 29 an. freeborni transmitted a geometric mean (gm) of 4.9 sporozoites and 80% of 30 an. gambiae transmitted a gm of 11.3 sporozoites. ingested sporozoites, in the blood meal immediately after feeding, were detected in 86.2% of 29 an. freeborni (gm = ... | 1992 | 1474388 |
| the population dynamics in mosquitoes and humans of two plasmodium vivax polymorphs distinguished by different circumsporozoite protein repeat regions. | the population dynamics of two plasmodium vivax polymorphs were studied over a two-year period in a village in a hyperendemic area of papua new guinea in both the mosquito and human populations. strains of p. vivax were distinguished by different circumsporozoite (cs) protein repeats, the vk210 (classic) and the vk247 (variant) polymorphs. in 1986, 34% of p. vivax cs protein-positive mosquitoes were of the vk247 type. although the proportion of p. vivax sporozoite antigen-positive mosquitoes com ... | 1992 | 1471735 |
| heme polymerase: modulation by chloroquine treatment of a rodent malaria. | the biosynthesis of the beta-hematin of malarial pigment (hemozoin) is catalyzed by a newly discovered enzyme, heme polymerase, which is described for plasmodium berghei in this report. this novel enzyme is present in the insoluble fraction of hemolysates of infected erythrocytes but is not present in normal erythrocytes. the substrate is ferriprotoporphyrin ix (fp) released from hemoglobin. at ph 5 and 37 degrees c the enzyme is saturated by 100 microm fp. the ph optimum is between 5 and 6 and ... | 1992 | 1474861 |
| a fourth family of the plasmodium falciparum s-antigen. | the s-antigen of plasmodium falciparum is a highly diverse heat stable protein that is located in the parasitophorous vacuole of the mature asexual intraerythrocytic parasite. the gene for s-antigen exists within the parasite population as multiple alleles at a single locus. its sequence contains a large central block of tandemly arranged peptides that are identical or very similar in one allele but differ widely in sequence, repeat length and number among different alleles, and consequently ant ... | 1992 | 1474992 |
| membrane-associated proteases process plasmodium falciparum merozoite surface antigen-1 (msa1) to fragment gp41. | the plasmodium falciparum merozoite surface antigen-1 (msa1) undergoes stage-specific processing; this processing appears isolate-specific during cleavage to fragment gp41. recombinant substrates were prepared from the two allelic forms of msa1; the mad20 substrate was cleaved at four sites in the molecule whilst the k1 form was cleaved once. however both parasite isolates, although expressing different allelic forms of msa1, possess the same repertoire of msa1-specific proteases. the cleavage s ... | 1992 | 1474993 |
| identification of a cryptic intron in the plasmodium vivax duffy binding protein gene. | | 1992 | 1474997 |
| mung bean nuclease exhibits an exon-excision activity upon the plasmodium falciparum sera gene. | | 1992 | 1474998 |
| structure of a plasmodium chabaudi acidic phosphoprotein that is associated with the host erythrocyte membrane. | we have characterized by molecular cloning and sequencing a plasmodium chabaudi antigen that is associated with the membrane of the infected erythrocyte throughout the entire intraerythrocytic cycle. the protein (pcema1) has a predicted size of 50 kda and contains a major tandem repeat array of 16 octapeptides that constitutes almost 30% of the protein. at its amino-terminus, pcema1 has a string of hydrophobic residues characteristic of a secreted protein, but does not contain a hydrophobic memb ... | 1992 | 1475002 |
| molecular analysis of plasmodium falciparum hexokinase. | hexokinase, a key glycolytic enzyme, is involved in the initial phosphorylation reaction of imported glucose and specific blocking of this activity may therefore arrest the development of malaria parasites. we describe here the cloning of a single copy hexokinase gene of plasmodium falciparum (pfhk) from cdna or genomic dna libraries. the deduced amino acid sequence of pfhk has 26% identity with human hexokinase i and its predicted molecular mass assigns it as an invertebrate type isoenzyme of h ... | 1992 | 1475005 |
| a review of malaria in iran, 1975-90. | since 1958, when the malaria eradication program officially started in iran, great strides has been made in controlling the disease in most of the country. however, because of certain technical, operational and administrative problems, malaria is still highly prevalent in southeastern iran, affecting 6% of the population. the situation of malaria in iran from 1975 through 1990 is discussed in detail, with particular emphasis given to the epidemiological characteristics and vector transmission fa ... | 1992 | 1474383 |
| malaria and pregnancy in cameroonian women. naturally acquired antibody responses to asexual blood-stage antigens and the circumsporozoite protein of plasmodium falciparum. | antibody responses to plasmodium falciparum antigens in women during pregnancy were investigated in mfou, a rural community in cameroon. the study consisted of cross-sectional analyses involving 225 pregnant women and 75 non-pregnant controls. blood samples were collected from each woman to determine serological reactivity to intraerythrocytic malarial antigens, ring-infected erythrocyte surface antigen (resa) and circumsporozoite (cs) repeat peptide (nanp)5 by the indirect fluorescent antibody ... | 1992 | 1475812 |
| morbidity from malaria and immune responses to defined plasmodium falciparum antigens in children with sickle cell trait in the gambia. | morbidity from plasmodium falciparum malaria and humoral and in vitro cellular immune responses to defined malaria antigens were measured in rural gambian children with haemoglobin phenotype as (hbas) and in those with a normal haemoglobin (hbaa). in a survey undertaken during the dry season, hbas children had a higher parasite rate than hbaa children but a lower prevalence of parasitaemia at a level of 500/microliters or greater. malariometric indices measured during a rainy season survey were ... | 1992 | 1475814 |
| diethylcarbamazine in the control of splenomegaly associated with bancroftian filariasis in the ok tedi area of papua new guinea. | bancroftian filariasis is highly endemic in the ok tedi region of papua new guinea, with a reported mean rate of 39% before the implementation of a single-dose diethylcarbamazine (dec) treatment programme in 1986. this was followed by a 72% decline in the rate of detectable microfilaraemia and a 40% reduction in pre- and post-treatment splenomegaly. no significant difference was observed when spleen enlargement was compared to the presence of patent malaria. a significant difference in splenomeg ... | 1992 | 1475824 |
| chloroquine-resistant plasmodium vivax in brazil. | | 1992 | 1475838 |
| chloroquine-resistant plasmodium vivax in brazil. | | 1992 | 1475839 |
| chloroquine-resistant plasmodium vivax in brazil. | | 1992 | 1475840 |
| strategies for the development of an antimalarial vaccine. | susceptible aotus monkeys were immunized with escherichia coli-derived fusion proteins containing partial sequences of the proteins msai, serp, hrpii and with a group of three recombinant antigens isolated by screening with an antiserum raised against the protective 41 kda protein band. hrpii, the combination of the fusion proteins of the 41 kda group and a mixture of two sequences of serp conferred significant protection against a challenge infection with plasmodium falciparum blood stages. bas ... | 1992 | 1471413 |
| autochtonous plasmodium falciparum malaria in southern france. | | 1992 | 1475808 |
| plastid origin of an extrachromosomal dna molecule from plasmodium, the causative agent of malaria. | several species of plasmodium have been shown to contain a circular extrachromosomal dna molecule which is widely supposed to be mitochondrial dna. however, it has recently been shown to have a number of features in common with chloroplast dna. here, a phylogenetic analysis of rna polymerase coding sequences from the plasmodium molecule has been carried out using distance matrix, maximum likelihood, parsimony and operator invariant methods. the analysis indicates that the molecule is in fact der ... | 1992 | 1474844 |
| three matrix metalloproteinases form a non-covalent association with the rhoptry-associated protein-1 of plasmodium falciparum. | during the characterization of malaria vaccine candidate proteins, three metalloproteinases having a molecular mass of 220, 95 and 70 kda were found to be co-isolated with the rhoptry-associated protein-1 (rap-1) complex, but not with rap-3 or gp195. these enzymes were also found in detergent extracts of saponin-lysed plasmodium falciparum. of nine proteinase inhibitors tested, only edta was found to abrogate activity. dose-dependent curves were determined for several metal ions and cobalt was f ... | 1992 | 1477099 |
| new trends in chloroquine efficacy in the treatment of malaria: significance of low (scanty) parasitaemia in an endemic area, with emerging chloroquine-resistant p. falciparum. | in a continuous malaria therapy surveillance, using in vivo (who) seven-day-test, extended to 14 days follow up, we evaluated the significance of low (scanty) parasitaemia, in an area with chloroquine resistance p. falciparum (crpf), where self-medication is widely practised. we found that 30.9 pc of the patients screened had plasmodium species, and 71.4 pc of these had low parasite counts of less than 500 parasites/mm3, whole blood. eight pc of these were febrile and 41.7 pc of the parasite str ... | 1992 | 1477881 |
| conservation of repeating structures in the pfemp2/mesa protein of plasmodium falciparum. | | 1992 | 1478701 |
| fluoxetine hydrochloride enhances in vitro susceptibility to chloroquine in resistant plasmodium falciparum. | the emergence of chloroquine resistance in plasmodium falciparum has necessitated the development of alternate strategies for chemotherapy and chemoprophylaxis. one approach has been the identification of drugs that do not possess any intrinsic antimalarial activity when used alone but that potentiate the effect of currently available antimalarial drugs, such as chloroquine. we identified fluoxetine hydrochloride (prozac), a commonly prescribed antidepressant, as another resistance modulator for ... | 1992 | 1482144 |
| rheological properties of rosettes formed by red blood cells parasitized by plasmodium falciparum. | a proportion of red blood cells parasitized by plasmodium falciparum form rosettes with non-parasitized red cells. although these rosettes are thought to impair microcirculatory flow, their rheological characteristics have not been fully described. using dual-micropipette manipulation to pull apart individual rosettes, we found that the forces binding rosettes together were strong (average force for removal of a cell was 4.4 x 10(-10) n, approximately 5 times that required to detach a parasitize ... | 1992 | 1482664 |
| superimposing two-dimensional gels to study genetic variation in malaria parasites. | two-dimensional polyacrylamide gel electrophoresis is a valuable tool for studying genetic variation in the human malaria parasite, plasmodium falciparum. it involves examining the position of protein spots in gel produced from different isolates. some spots have been seen to vary, while others have had a constant position in all isolates so far examined. these invariant spots provide a reference frame to compare variations in other spots. this paper discusses the usefulness of digital image han ... | 1992 | 1483429 |
| chloroquine resistant plasmodium falciparum malaria in calcutta. | | 1992 | 1484005 |
| alpha-tubulin ii is a male-specific protein in plasmodium falciparum. | the tubulin gene family in plasmodium falciparum consists of one beta-tubulin and two alpha-tubulin genes (alpha-tubulin i and ii). we present here data indicating that alpha-tubulin ii is expressed only in male sexual stage parasites. an igm mab, 5e7, specifically reacted with stage iii (day 4-5) through mature (day 10-11) male gametocytes and with emerging, exflagellating, or freely moving male gametes. no reactivity was detected in female gametocytes, female gametes, sporozoites, or asexual p ... | 1992 | 1484548 |
| nucleotide sequence of a plasmodium falciparum stress protein with similarity to mammalian 78-kda glucose-regulated protein. | | 1992 | 1484559 |
| antibody response in plasmodium vinckei malaria after treatment with chloroquine and adjuvant interferon-gamma. | the antibody response of mice infected with plasmodium vinckei after treatment with chloroquine either alone or in combination with interferon-gamma (ifn-gamma) was determined. sequential serum samples were drawn from balb/c mice receiving either 240 micrograms chloroquine on the day of infection or 120 micrograms chloroquine plus 10(4) units ifn-gamma daily for 11 days beginning on day 3 prior to infection. mice treated with additional ifn-gamma showed an early induction of igg2a response and a ... | 1992 | 1480597 |
| preparation of dna from blood for polymerase chain reaction in microtiter dish. | | 1992 | 1479896 |
| prolonged in vitro cultivation of plasmodium vivax using trager's continuous-flow method. | | 1992 | 1480609 |
| [malaria. epidemiology, etiology, physiopathology, diagnosis, development, prognosis, treatment, prevention]. | | 1992 | 1485101 |
| molecular karyotype analysis in leishmania. | the advent of pulsed field electrophoresis has allowed a direct approach to the karyotype of leishmania. the molecular karyotype thus obtained is a stable characteristic of a given strain, although minor modifications may occur during in vitro maintenance. between 20 and 28 chromosomal bands can be resolved depending on the strain, ranging in size from approximately 250 to 2600 kb. the technique has revealed a striking degree of polymorphism in the size and number of the chromosomal bands betwee ... | 1992 | 1485351 |
| malarial lipids. an overview. | | 1992 | 1485354 |
| genetic analysis of malaria parasites. | | 1992 | 1485355 |
| ultrastructural changes in the blood-brain barrier of mice infected with plasmodium berghei. | mice infected with the rodent malaria parasite plasmodium berghei exhibit ultrastructural changes of the blood-brain barrier during the course of infection. firm adherence including cellular interdigitation of infected cells or leucocytes and even clusters of cells to the vascular-endothelial lining is repeatedly observed early during infection. ghosts and membrane remnants can be found engulfed in the surface of the endothelial cells. frequently leucocytes migrate between endothelial cells and ... | 1992 | 1485495 |
| effects of three compounds extracted from morinda lucida on plasmodium falciparum. | the effects of three compounds, digitolutein (1), rubiadin 1-methyl ether (2) and damnacanthal (3) extracted from the stem bark and the roots of morinda lucida benth. on the growth of plasmodium falciparum in vitro were investigated. the number of parasites (schizonts) decreased significantly in a dose-dependent manner, and 100% of inhibition was obtained with 30 to 40 micrograms of each compound tested. the ic50 values were calculated. | 1992 | 1484892 |
| in vitro antimalarial activity and chloroquine potentiating action of two bisbenzylisoquinoline enantiomer alkaloids isolated from strychnopsis thouarsii and spirospermum penduliflorum. | the bisbenzylisoquinolines 7-o-demethyltetrandrine and limacine, respectively, isolated from strychnopsis thouarsii baill. and spirospermum penduliflorum thou. were evaluated for their intrinsic antimalarial activity in vitro and chloroquine potentiating action against the chloroquine-resistant plasmodium falciparum fcm 29 originating from cameroon. they both showed significant antiplasmodial potency in vitro with very similar ic50 values of respectively, 740 nm and 789 nm (ic50 = 214 nm for chl ... | 1992 | 1484894 |
| [genetic aspects of sickle cell anemia]. | the genetics of sickle cell anemia may be considered as a model. its mendelian transmission was hypothesized even before the molecular era. once the mutation identified, it could be studied at the protein and dna level; a consistent pathophysiological mechanism was proposed; the various genetic forms of the disease could be identified; the way by which a balanced polymorphism with plasmodium falciparum malaria is obtained was analyzed. more recently, investigations were run in order to understan ... | 1992 | 1485080 |
| plasmodium falciparum synthesizes 43000 daltons protein containing o-linked glucosamine. | | 1992 | 1487047 |
| testosterone-induced suppression of self-healing plasmodium chabaudi malaria: an effect not mediated by androgen receptors? | this study investigates whether androgen receptors (ar) mediate the suppressive effect of testosterone on self-healing plasmodium chabaudi malaria. our data show the following. (1) female and castrated male mice of the inbred strain c57bl/10 self-heal and survive infections when challenged with 10(6) p. chabaudi-parasitized erythrocytes. however, self-healing is prevented when circulating testosterone levels are high as in intact males or in females and castrated males pretreated with 0.9 mg tes ... | 1992 | 1487694 |
| inducible transport systems in the regulation of parasite growth in malaria-infected red blood cells. | | 1992 | 1487065 |
| application of a simple culture of plasmodium berghei for assessment of antiparasitic activity. | mouse erythrocytes infected with plasmodium berghei were incubated for a short period in microplate wells. the parasites changed morphologically from the immature ring form to mature schizonts, and free merozoites were released. however, reinvasion of the erythrocytes appeared not to be possible in this system. this intraerythrocytic one-step growth of the parasite could be determined quantitatively by counting incorporation of 3h-hypoxanthine. the incorporation was markedly decreased by additio ... | 1992 | 1487372 |
| molecular cloning of plasmodium falciparum blood stage antigens and application of the recombinant proteins in serodiagnosis. | a plasmodium falciparum genomic dna library was established in the expression vector lambda gt11, cloned in escherichia coli. the library was screened with human hyperimmune sera by in situ hybridization. twenty clones expressing p. falciparum sequences as polypeptides fused to beta-galactosidase were identified. one, cd3a/9025/60, reacted with all immune sera and expressed polypeptides that were larger than beta-galactosidase as well as reacting with antibodies to beta-galactosidase and to p. f ... | 1992 | 1488692 |
| in vitro sensitivity of plasmodium falciparum isolates in thailand to quinine and chloroquine, 1984-1990. | | 1992 | 1488713 |
| malaria and the red cell membrane. | malarial parasites are primarily parasites of red cells and during infection ingest most of the haemoglobin within these cells, leaving the membrane as the only vestige of the original host cell. the red cell membrane thus plays a key role at all stages of infection with malarial parasites, and is modified in many ways during parasitisation, so that at least functionally it has little resemblance to the membrane from which it was originally derived. the highly specific and ordered process of par ... | 1992 | 1486287 |
| a developmental mutation (npfl1) resulting in cell death in physarum polycephalum. | in physarum, microscopic uninucleate amoebae develop into macroscopic multinucleate plasmodia. in the mutant strain, ra614, plasmodium development is blocked. ra614 carries a recessive mutation (npfl1) in a gene that functions in sexual as well as apogamic development. in npfl+ apogamic development, binucleate cells arise from uninucleate cells by mitosis without cytokinesis at the end of an extended cell cycle. in npfl1 cultures, apogamic development became abnormal at the end of the extended c ... | 1992 | 1487727 |
| ion transport in parasitic protozoa. | many parasitic protozoa go through complex life cycles in the course of which they adapt to widely different environments; ion transport processes are expected to play a role both in pathogenicity and in adaptation. so far, studies on ion transport have been virtually limited to leishmania, plasmodium and entamoeba. the distribution of ion pumps in the former two organisms generally appears to conform to the picture established for other protozoa, i.e. a proton-motive p-atpase in the plasma memb ... | 1992 | 1491229 |
| a bioassay for mefloquine. | a bioassay method that allows for the estimation of serum concentrations of mefloquine is presented. concentrations obtained by bioassay and high performance liquid chromatography showed a good correlation. this bioassay should be helpful in assessing prophylactic/treatment failures to mefloquine under field conditions. | 1992 | 1491307 |
| on-site diagnosis of plasmodium falciparum, p. vivax, and p. malariae by using the quantitative buffy coat system. | the quantitative buffy coat (qbc) system was used for the detection and identification of malaria parasites in blood specimens from 570 residents of oksibil, an isolated highland valley in the eastern jayawijaya mountains of irian jaya (indonesian new guinea). the availability of a battery-powered centrifuge and a fiberoptic paralens enabled us to complete and interpret the assay in this remote environment. of 322 qbc tubes examined for 2-4 min each, results of 295 (92%) concurred with findings ... | 1992 | 1491313 |
| malariometric survey in keoudom district, laos: sensitivity of plasmodium falciparum to anti-malarials and automedication with chloroquine. | a malariometric survey was conducted in the keoudom district, in the northern part of vientiane province, laos, where an artificial dam-lake on the nam river is located. the parasite rate of the whole cohort representing 1,105 subjects was 2.44% with the predominance of plasmodium vivax (70%), while p. falciparum represented 30% with the average parasite density index 3. the low spleen rate (2.3%) characterized the study area as a hypoendemic zone. ifat antibodies were examined in 419 subjects. ... | 1992 | 1488689 |
| cellular and molecular analysis of plasmodium development in physarum. | the development of an amoeba into a plasmodium involves extensive changes in cellular organisation and gene expression. the genetic basis of a number of recessive mutations that block plasmodium development has been elucidated. the stage at which development becomes abnormal has been determined for all the mutants, as has the terminal phenotype. in order to investigate the changes in gene expression that accompany plasmodium development, a cdna library has been made using rna isolated from cell ... | 1992 | 1490279 |
| [parasitemia in plasmodium falciparum malarial attacks in children]. | in order to evaluate the predictive value of parasitaemia, this parameter was measured on admission in 69 gabonese children aged from 3 to 13 years hospitalized for plasmodium falciparum malarial attacks. fourteen of these children had cerebral malaria, 5 had isolated convulsions and 50 had uncomplicated attacks. the parasitaemia values measured were compared with those found in asymptomatic children of the same age range carrying trophozoites. there were no significant differences in mean paras ... | 1992 | 1492080 |
| high-performance liquid chromatographic determination of dihydroorotate dehydrogenase of plasmodium falciparum and effects of antimalarials on enzyme activity. | a reversed-phase high-performance liquid chromatographic technique for the determination of dihydroorotate dehydrogenase in plasmodium falciparum was developed. the assay was applied to the evaluation of the effects of several antimalarial drugs on the enzyme. treatment of both the asexual and gametocyte stages of p. falciparum in culture with menoctone, primaquine or the primaquine derivative wr 238605 led to depression of the enzyme activity, although the drugs did not appear to inhibit the en ... | 1992 | 1491058 |
| peptide binding to mhc class i proteins measured with a novel fluorescent technique. | an n-dansylated peptide derived from the plasmodium berghei circumsporozoite protein (pbcs 253-260) bound in an allele-specific manner to a single-chain kd molecule (sc-kd), and its binding resulted in significant fluorescent enhancement. the binding kinetics of unlabelled peptides could be determined by pre-incubating dansylated pbcs with a concentrated suspension of sc-kd, and then diluting this mixture in the presence of unmodified peptide. the time-dependence of the ensuing fluorescence decr ... | 1992 | 1493573 |
| plasmodium vinckei petteri: identification of the stages sensitive to arteether. | antimalarial activity of arteether, a derivative of artemisinin (qinghaosu) against blood-induced infections of the highly synchronous plasmodium vinckei petteri rodent species of malaria was evaluated in swiss mice. a single subcurative dose of arteether of 2.2 mg/kg body weight was injected subcutaneously to mice, either during the prepatent period or during the patent infection, when different stages of the parasitic cycle were present in the blood. it was shown that rings and young trophozoi ... | 1992 | 1493877 |
| antimalarial drug resistance: the pace quickens. | | 1992 | 1493976 |
| [angkor. the mystery of the dead city and anopheles dirus]. | the desertion of angkor, which during more than five centuries was the center of a glorious civilization, has long been a matter of mystery and conjecture. the discovery of the vectorial capacity of the jungle mosquito anopheles dirus, its epidemiological importance in the emergence and spread of multidrug resistance in plasmodium falciparum malaria, the wiping out of large populations after transfer or deportation of non-immune khmers into forest areas can now easily explain the desertion of an ... | 1992 | 1494307 |
| [participation of cytokines and immune sera to the cytoadherence of erythrocytes infected by plasmodium falciparum on the endothelial cells in culture]. | in vitro binding capacity of erythrocytes infected with p. falciparum and the modulation of cytoadherence on human endothelial cells by cytokines and sera from semi immune subjects in relation to cytoadherence were studied. tumor necrosis factor and interleukin-3, alone or in combination with granulocyte macrophage-colony stimulating factor, enhanced in vitro cytoadherence. contrary to pooled immune sera, patients' sera obtained during acute or convalescent phase did not reverse nor inhibit in v ... | 1992 | 1493578 |
| experimental plasmodium falciparum cerebral malaria in the squirrel monkey saimiri sciureus. | infection of the squirrel monkey, saimiri sciureus, with several strains of plasmodium falciparum leads in a proportion of animals to neurological symptoms with a fatal outcome. this first simian model for human cerebral malaria was studied with three strains of parasites, the uncloned palo alto(fup-1) strain, the palo altoplf3 clone mhb11, and the recently monkey-adapted p. falciparum strain ipc/ray. cerebral malaria could develop during primo infection of monkeys, whether the animals had been ... | 1992 | 1493871 |
| multiple transmission of plasmodium gallinaceum (eucoccida: plasmodiidae) during serial probing by aedes aegypti (diptera: culicidae) on several hosts. | mosquitoes salivate before ingesting blood, and sporozoites are transmitted during this phase of feeding. in the laboratory, malaria-infected aedes aegypti were allowed to probe on a series of three chicks during a 5-min period. probing on each host was interrupted after 10 s. our results demonstrate that up to three hosts can be serially infected with avian malaria during a 5-min period. | 1992 | 1495052 |
| cyclical transmission of plasmodium berghei (coccidiida: plasmodiidae) by anopheles omorii (diptera: culicidae). | anopheles omorii, a tree-hole breeding anopheline collected in japan, transmitted a rodent malaria, plasmodium berghei anka strain, in the laboratory. mice with 0.2-15% parasitemia, 0.01-1.5% gametocytemia, and 0.001-0.5% exflagellations were used as infective hosts. oocyst numbers ranged from 2 to 171 (mean 44) on the midgut 8-16 d after the blood meal. several to hundreds of sporozoites were detected in the salivary glands 14 d after feeding. the mosquitoes were infective to mice from 13 to 40 ... | 1992 | 1495055 |
| malaria transmission by anopheles subpictus (diptera: culicidae) in a new irrigation project in sri lanka. | indoor resting anopheles subpictus in a new irrigation scheme in sri lanka were investigated during 1989-1990 for malaria infection by dissection and elisa, and human feeding rates by elisa analysis of blood meals. indoor resting abundance was 22.3 females per house per 15-min catch in april-june 1989, 2.2 in november-december 1989, and 7.5 in april-june 1990. elisa-based malaria infection rates (plasmodium vivax and p. falciparum combined) were 1.4% during april-june and 3.2% during november-de ... | 1992 | 1495065 |
| efficacies of chloroquine, pyrimethamine/sulphadoxine and pyrimethamine/sulphalene against p. falciparum in northeastern nigeria. | the clinical and parasitologic efficacies of oral chloroquine phosphate, pyrimethamine/sulphadoxine and pyrimethamine/sulphalene in treating plasmodium falciparum malaria were assessed in selected sites of northeastern nigeria (zone d of the primary health care (phc) programme) using a 14-day standard in-vivo protocol during 1988-1990. of a total of 2056 children under 5 years screened for infection, for chloroquine trials, 1189 (57.8%) were positive for plasmodium infection. one hundred and sev ... | 1992 | 1495121 |
| plasmodium falciparum: chymotryptic-like proteolysis associated with a 101-kda acidic-basic repeat antigen. | malaria proteinases appear to function in the release of merozoites from infected erythrocytes and the invasion of merozoites into erythrocytes. chymostatin, an inhibitor of chymotrypsin-like proteinases, inhibits malaria invasion and also inhibits apparent autoproteolysis of a 101-kda acidic-basic repeat antigen (p101-abra) that is found in the vacuolar space surrounding merozoites in plasmodium falciparum-infected erythrocytes. after purification by a monoclonal antibody (mab 3d5), p101-abra d ... | 1992 | 1493872 |
| probing the molecular basis of resistance to pyrimethamine by site-directed mutagenesis. | | 1992 | 1495020 |
| a family of erythrocyte binding proteins of malaria parasites. | malaria erythrocyte binding proteins use the duffy blood group antigen (plasmodium vivax and plasmodium knowlesi) and sialic acid (plasmodium falciparum) on the erythrocyte surface as receptors. we had previously cloned the one p. vivax gene, the one p. falciparum gene, and part of one of the three p. knowlesi genes encoding these erythrocyte binding proteins and described the homology between the p. knowlesi and p. vivax genes. we have completed the cloning and sequencing of the three p. knowle ... | 1992 | 1496004 |
| parasitological, clinical and haematological response of children with plasmodium falciparum to 4-aminoquinolines and to pyrimethamine-sulfadoxine with quinine in western kenya. | children with plasmodium falciparum infections in western province, kenya, were studied in 1987 for their parasitological, clinical and haematological response to chloroquine, to amodiaquine and to pyrimethamine-sulfadoxine plus quinine. ninety-eight children under 5 years of age were treated in 1 of 2 hospitals. of the 56 patients treated with chloroquine base 25 mg/kg, 91% had resistant infections, with 36% having no significant decrease in parasitaemia (riii resistance); however, 69% responde ... | 1992 | 1496699 |
| chloroquine resistance of plasmodium falciparum in bukumbi, tanzania. an in vivo study. | the sensitivity of plasmodium falciparum to chloroquine was studied in 42 children in bukumbi, tanzania. the standard who in vivo test was used, and chloroquine phosphate 25 mg base/kg was administered in divided doses over three days. from the 42 patients 13 (31%) were sensitive to chloroquine and 29 (69%) had not cleared their parasites on day 7. from the resistant cases, 1 showed ri resistance (early recrudescence), 6 showed rii resistance and 18 cases showed riii resistance. four were resist ... | 1992 | 1496715 |
| evaluation of 5.1-[nanp]19, a recombinant plasmodium falciparum vaccine candidate, in adults. | in a randomized single-blind study, 13 healthy adult volunteers were subcutaneously immunized with 2 or 3 single 50 or 400 micrograms doses of a plasmodium falciparum recombinant vaccine candidate designated 5.1-[nanp]19. the vaccine caused transitory reactions at the injection site. eight (62%) volunteers had a greater than or equal to 4-fold increase of antibody titer against sporozoites in immunofluorescence assay, all 13 seroconverted in igg enzyme-linked immunosorbent assay against [nanp]50 ... | 1992 | 1496731 |
| a specific dna probe which identifies babesia bovis in whole blood. | a genomic library of babesia bovis dna from the mexican strain m was constructed in plasmid pun121 and cloned in escherichia coli. several recombinants which hybridized strongly to radioactively labeled b. bovis genomic dna in an in situ screening were selected and further analyzed for those which specifically hybridized to b. bovis dna. it was found that pmu-b1 had the highest sensitivity, detecting 25 pg of purified b. bovis dna, and 300 parasites in 10 microliters of whole infected blood, or ... | 1992 | 1496779 |
| malaria transmission and vector biology on sainte marie island, madagascar. | a 17-mo longitudinal malaria survey (november 1988-march 1990) was carried out on sainte marie island, an area on the east coast of madagascar which is frequently visited by tourists. during 706 man-nights of capture, 46,401 mosquitoes belonging to 32 species were caught. sporozoite rates were determined by elisa and incriminated anopheles gambiae giles s.s., an. funestus giles, and an. mascarensis de meillon as vectors of malaria. an. gambiae, the main vector, was highly anthropophilic but larg ... | 1992 | 1495029 |
| labeling and initial characterization of polar lipids in cultures of plasmodium falciparum. | the present report describes the radioactive labeling of polar lipids in in vitro cultures of plasmodium falciparum as well as their extraction with organic solvents and their partial characterization by chemical and enzymatic methods. all substances detected could be cleaved by alkali, suggesting that they were esters rather than sphingolipids or compounds containing alkyl groups. dolichol-cycle intermediates were not detected. phosphatidylinositol, phosphatidylethanolamine, and phosphatidylcho ... | 1992 | 1495920 |
| immunoprotection in mice susceptible to waning memory against the pre-erythrocytic stages of malaria after validated immunisation with irradiated sporozoites of plasmodium berghei. | the induction of immunity by irradiated sporozoites has been a bench-mark of immunological protection against the malaria parasite. herein we confirm that different mouse strains exhibit different susceptibilities to sporozoite-induced infection of plasmodium berghei. we note, however, that after hepatic schizogony, early parasite growth in the blood demonstrates no strain preference between c57bl/6 and balb/c mice. sporozoite-susceptible c57bl/6 mice, although initially protected by irradiated ... | 1992 | 1495922 |
| specific inflammatory cell infiltration of hepatic schizonts in balb/c mice immunized with attenuated plasmodium yoelii sporozoites. | we compared immunization of balb/c mice with radiation-attenuated versus killed sporozoites of the rodent malaria parasite, plasmodium yoelii. we employed a suboptimal schedule of only two immunizations, in expectation that some parasites might break through the resultant low level immunity and that it might thus be possible to study the response of the host against these 'breakthrough' schizonts. as a measure of protective immunity, we used histological means to determine the percentages of cha ... | 1992 | 1498082 |
| effects of cytokines, complement, and antibody on the neutrophil respiratory burst and phagocytic response to plasmodium falciparum merozoites. | the interaction between plasmodium falciparum merozoites and human neutrophils, as well as the role of cytokines, complement, and antimalarial antibody on this interaction, was examined in vitro by measuring luminol-dependent chemiluminescence and phagocytosis. merozoites, in the presence of heat-inactivated (56 degrees c/30 min) normal serum, had very little effect on the neutrophil chemiluminescence. this response was significantly enhanced by the addition of normal serum (containing normal co ... | 1992 | 1500183 |
| expression of the eukaryotic trypanosoma cruzi cra gene in yersinia enterocolitica and induction of an immune response against cra in mice. | the 70-kb plasmid pyv of yersinia enterocolitica directs the secretion of a set of proteins, called yops, that are produced during infection of humans and animals. trypanosoma cruzi, the agent of american trypanosomiasis, synthesizes a cytoplasmic protein termed cra that is considered to be t. cruzi specific. to produce cra in y. enterocolitica, we constructed a hybrid yope-cra gene that we integrated into plasmid pyv by homologous recombination. recombinant y. enterocolitica produced a chimeric ... | 1992 | 1500192 |
| [malaria]. | | 1992 | 1500255 |
| are eukaryotic ribosomes heterogeneous? affirmations on the horizon. | | 1992 | 1497854 |
| the pathophysiology of malaria. | | 1992 | 1496930 |
| structure and possible function of heat-shock proteins in falciparum malaria. | like many prokaryotes and eukaryotes, the malaria parasite also synthesizes several stress proteins. most widely studied stress proteins of this parasite are the heat-shock proteins (hsps). their discovery in malaria is a gift of recombinant dna technology. five hsp genes from plasmodium falciparum have been identified which are located on different chromosomes. thus the inheritance and expression of hsp genes are independent of each other. they share a large amount of sequence homology at n-ter ... | 1992 | 1499283 |
| immune response of gametocytes of plasmodium falciparum in exogenous cases in dakahlia governorate, egypt. | following chloroquine treatment gametocytes numbers fell with a constant rate of loss over a period from 15-21 days. the gametocytes had a half-life of 2-4 days. the sex ratio was constant 4 female: 1 male. antibodies to the gametocytes were detected in some patients. it was concluded that the gametocytes of p. falciparum are long-lived and can stimulate antibody production but the immune response appears to play no part in their elimination, which probably takes place in the spleen as a part of ... | 1992 | 1500775 |
| rapid and simple method for isolating malaria dna from fingerprick samples of blood. | | 1992 | 1501643 |
| characterization of the gene encoding sporozoite surface protein 2, a protective plasmodium yoelii sporozoite antigen. | sporozoite surface protein 2 (ssp2) is a 140-kda, protective sporozoite surface protein from plasmodium yoelii distinct from the circumsporozoite protein (csp). a genomic clone containing the ssp2 gene was isolated and sequenced to determine its size, structural organization and deduced primary amino acid sequence. the coding sequence consists of a single, long open reading frame encoding 826 amino acids. the overall structure of ssp2 is similar to that of the csp, consisting of a central region ... | 1992 | 1501644 |
| intramolecular mapping of plasmodium falciparum p126 proteolytic fragments by n-terminal amino acid sequencing. | protein p126 (also called p140, p113, sera, serp1) is a major parasitophorous vacuole antigen of plasmodium falciparum. this protein is processed upon merozoite release into 2 fragments of 73 kda (p73) and 50 kda (p50), which are found in the culture medium. p73 is composed of 2 polypeptides of 47 and 18 kda linked by disulfide bridges. in the presence of leupeptin, an inhibitor of serine and cysteine proteases which inhibits merozoite release, a 56-kda intermediate product (p56) is recovered in ... | 1992 | 1501648 |
| dispiro-1,2,4,5-tetraoxanes: a new class of antimalarial peroxides. | dispiro-1,2,4,5-tetraoxanes 2-4 were synthesized as potential peroxide antimalarial drugs. they had curative activity against plasmodium berghei in vivo at single doses of 320 and 640 mg/kg which confirms earlier unpublished data. moreover, artemisinin (1) and 4 had equivalent ed50's against p. berghei in vivo in the multiple-dose thompson test; neither showed any evidence of acute toxicity at total doses of more than 12 g/kg. dispiro-1,2,4,5-tetraoxane 4 had ic50's comparable to those of 1 agai ... | 1992 | 1501229 |
| random mating of natural plasmodium populations demonstrated from individual oocysts. | dna amplified from individual plasmodium vivax oocysts, produced by feeding mosquitoes directly on naturally infected humans in thailand, was used to study cross-mating of 2 polymorphs of the circumsporozoite (cs) gene, vk 210 and vk 247. alleles were detected in matched blood parasites, sporozoites, and individual oocysts with oligoprobes specific to characteristic repeat units. oocysts developing from 3 cases in which mixed alleles were present in the blood parasites had genotype frequencies, ... | 1992 | 1501632 |