Publications

response of human sera from faiyum governorate, egypt, to three plasmodium antigens using the ifa technique.		1983	6355325
the use of metrizamide for isopyknic separation and enrichment of plasmodium falciparum schizonts from continuous culture.	plasmodium falciparum-parasitized erythrocytes obtained from continuous in vitro cultures were fractionated over metrizamide density gradients. late developmental stage schizonts were isolated from uninfected erythrocytes and other intracellular blood stage forms (rings and trophozoites) by centrifugation through 15% metrizamide. schizonts comprised, on the average, 85% of the total number of cells recovered from the top fraction of the gradient with the remaining cells being predominantly uninf ...	1983	6349396
regulation of the immune response in plasmodium falciparum malaria. i. non-specific proliferative responses in vitro and characterization of lymphocytes.	the mitogen-induced dna synthesis in vitro in lymphocytes from 20 patients acutely ill with plasmodium falciparum malaria was compared with that of 16 healthy donors. within both groups part of the donors were individuals who had only experienced short exposure or none at all to the parasite (sweden) while the other part were donors living in a malaria endemic area (colombia). the proliferative response to the t cell mitogen la (leucoagglutinin from pha) of the patients was significantly reduced ...	1983	6349879
[vaccination against malaria. needs, previous studies and possibilities].		1983	6349072
scanning electron microscope-analysis of the protrusions (knobs) present on the surface of plasmodium falciparum-infected erythrocytes.	the nature of the surface deformations of erythrocytes infected with the human malaria parasite plasmodium falciparum was analyzed using scanning electron microscopy at two stages of the 48-h parasite maturation cycle. infected cells bearing trophozoite-stage parasites (24-36 h) had small protrusions (knobs), with diameters varying from 160 to 110 nm, and a density ranging from 10 to 35 knobs x micron-2. when parasites were fully mature (schizont stage, 40-44 h), knob size decreased (100-70 nm), ...	1983	6350320
[chloroquine resistant malaria caused by p. falciparum in east africa. apropos of 2 cases].	the authors report two additional cases of malaria due to chloroquine-resistant plasmodium falciparum, one from tanzania, the other from kenya. in addition to the in vivo observations, these strains were thoroughly investigated by chloroquine assay and evaluation of ed50 using an original method (in vitro semi-microtest).	1983	6354497
[results of examining malaria patients by an immunofluorescence method using homologous and heterologous antigens].		1983	6355800
[results of an in vivo and in vitro study of the chloroquine sensitivity of imported strains of p. falciparum].		1983	6355801
clones of different sensitivities in drug-resistant isolates of plasmodium falciparum.	clones of two thai isolates of plasmodium falciparum were prepared and examined for variations in drug susceptibility and electrophoretic properties of enzymes. both isolates were found to include mixtures of genetically distinct parasites. of particular significance was the finding that one isolate (t(9)), which on initial testing was resistant to chloroquine, pyrimethamine and sulfadoxine-pyrimethamine, yielded a clone of parasites markedly more sensitive to these three drugs, while five other ...	1983	6354506
a double-blind comparative clinical trial of mefloquine and chloroquine in symptomatic falciparum malaria.	a total of 99 male zambian patients with symptomatic falciparum malaria were treated in a double-blind randomized manner with either mefloquine (1000 mg given in one day) or chloroquine (1500 mg given over 3 days). an s-type response was seen in all the chloroquine patients and 98% of the mefloquine group; one patient in the latter group (2%) showed an ri-type response, but the parasites obtained during the recrudescence were sensitive to both chloroquine and mefloquine in the in vitro microtest ...	1983	6354507
immunological aspects in plasmodium falciparum infection.	patients with p. falciparum infection were shown to have circulating immune complexes in their sera detected by the inhibition of igg-coated latex agglutination with rf factor and by the eac rosette inhibition test. low numbers of t cells and high numbers of b cells which contain immunoglobulins were demonstrated. t-cell depletion may be caused by antibody to t-lymphocytes being present in the sera of these patients.	1983	6355479
rapid identification and detection of parasitized human red cells by automated flow cytometry.	rapid and reliable identification of various human red cells parasites is important in many chemotherapeutic and immunologic studies. because manual microscopic counting is tedious and imprecise, we have developed a simple diagnostic procedure for the automated flow cytometric detection of in vitro infected red cells, using a nucleic acid-binding fluorescent dye, acridine orange. human malaria (plasmodium falciparum)-infected red cells from continuous human erythrocyte culture were incubated at ...	1983	6354641
seroepidemiology of malaria in northern thailand.	the seroepidemiology of malaria in two areas of northern thailand was studied by means of the indirect immunofluorescent antibody tests (ifat). in one transmission has been interrupted completely for over 30 years, but in the other area transmission still occurs at a low level. results of the survey for antibodies confirm existing parasitological findings and reflect both the recent and past history of malaria in both areas. the ifat is less sensitive to recent malaria infection in very young pe ...	1983	6356382
the use of chloramphenicol in the continuous culture of plasmodium falciparum.		1983	6356383
acetylcholinesterase activity in red cells infected with plasmodium falciparum culture in vitro.		1983	6356385
surface antigens of malaria merozoites. a high molecular weight precursor is processed to an 83,000 mol wt form expressed on the surface of plasmodium falciparum merozoites.	a technique was developed for obtaining high yields of naturally released plasmodium falciparum merozoites from synchronous cultures of parasitized erythrocytes. the cultured erythrocytes were treated with trypsin to prevent reinvasion (6), and the released merozoites that accumulated extracellularly were harvested by differential centrifugation. the total biosynthetically labeled proteins of schizonts and merozoites, and those immunoprecipitated by human immune serum were analyzed and compared. ...	1983	6355363
in vitro confirmation of clinical resistance of plasmodium falciparum to chloroquine in kenya.		1983	6353690
riboflavin status and malaria in infants in papua new guinea.		1983	6353691
retinal hemorrhage, a common sign of prognostic significance in cerebral malaria.	retinal hemorrhages were seen in 21 patients among a group of 144 with strictly-defined cerebral malaria. hemorrhages were multiple in 17 cases and bilateral in 14. there was subhyaloid extension in two. soft exudates were seen in two, the retinae were considered edematous in four and in one there was bilateral papilledema. retinal hemorrhages were significantly associated with several indices of severity of plasmodium falciparum infection: high parasitemia with schizontemia, anemia, elevated se ...	1983	6353955
an in vitro assay system for the identification of potential antimalarial drugs.	current models for antimalarial drug screening generally measure the survival of drug-treated rodents infected with plasmodium berghei. modifications of existing continuous culture methods for p. falciparum allow the rapid, accurate and economical determination of drug effects directly against the human pathogen. parasite cultures can be maintained in rpmi 1640 medium supplemented with human or rabbit serum or with hypoxanthine-supplemented bovine serum. the antiparasite effects of four drugs, c ...	1983	6355423
field evaluation in kenya of a 48-hour in vitro test for plasmodium falciparum sensitivity to chloroquine.	a 48-hour in vitro test for determining the chloroquine sensitivity of plasmodium falciparum isolates was evaluated in kisumu and malindi, kenya. p. falciparum isolates from 14 children, aged 5 to 13 years, were studied. in vivo and 48-hour in vitro tests were done on all 14. successful rieckmann macro and micro in vitro tests for chloroquine sensitivity were completed in nine isolates each. all 14 infections cleared within 3 days of beginning chloroquine treatment, and none recrudesced during a ...	1983	6353956
gametocyte formation by the progeny of single plasmodium falciparum schizonts.	gametocytogenesis of the malaria parasite plasmodium falciparum was studied in monolayers of erythrocytes attached to tissue culture dishes. merozoites produced by single schizonts in erythrocytes overlaying the monolayer infected the attached erythrocytes and produced clusters of progeny. parasites in these readily indentifiable clusters then underwent either asexual growth or sexual differentiation. the progeny of most schizonts yielded no gametocytes. however, the progeny of those schizonts t ...	1983	6355424
[importance of immunodiagnosis in studying the spread of quartan malaria].		1983	6355799
antimalarial activity of bruceantin in vitro.		1983	6357122
target antigens of transmission-blocking immunity on gametes of plasmodium falciparum.	three proteins of apparent molecular weights on reducing sds-page of 255, 59, and 53 kilodaltons have been identified as the targets on gametes of p. falciparum malaria of two monoclonal antibodies (mabs) that act synergistically to block transmission of the parasites to mosquitoes.	1983	6350527
antigens of the erythrocytes stages of the human malaria parasite plasmodium falciparum detected by monoclonal antibodies.	a range of 22 mouse anti-p. falciparum monoclonal antibodies have been characterized by indirect immunofluorescence and immunoprecipitation. on the basis of these studies, 5 groups of antibodies and 6 classes of antigen were defined. group i antibodies give, bright, uniform, generalised staining of all blood stages including gametocytes. three of these antibodies precipitate a metabolically labelled molecule(s) of 35 kda. one precipitates a 50 kda antigen. group ii antibodies, which give strong ...	1983	6350871
plasmodium falciparum: attenuation by irradiation.	the effect of irradiation on the in vitro growth of plasmodium falciparum was investigated. the cultured malarial parasites at selected stages of development were exposed to gamma rays and the sensitivity of each stage was determined. the stages most sensitive to irradiation were the ring forms and the early trophozoites; late trophozoites were relatively insensitive. the greatest resistance was shown when parasites were irradiated at a time of transition from the late trophozoite and schizont s ...	1983	6357833
malaria: the fight goes on.		1983	6358493
chloroquine resistance in plasmodium falciparum from kenyan infants.	forty-two infants, aged 6 to 24 months, infected with plasmodium falciparum were identified in kisumu, kenya. because of their age, all were presumably not semi-immune to malaria. each infant was treated with 25 mg/kg chloroquine base and followed for 7 days. forty-one infections were sensitive to chloroquine in vivo; asexual parasites disappeared in all by day 4 and were not present on days 5, 6, or 7. one infection was resistant in vivo; parasites disappeared by day 3 but recrudesced on day 4. ...	1983	6353957
[malarial hemolysis and renal insufficiency].	the authors report on 5 cases of malarial haemolytic anemia associated with renal insufficiency over a 3 years period at girard and robic hospital resuscitation department. as the occurrence of these forms is somewhat frequent in madagascar, the differential diagnosis has to be established from cerebral malaria. the primary diagnostic difficulties are reviewed, the various kinds of renal insufficiency are considered and the physico-pathologic troubles are anticipated. the prognosis is relatively ...	1983	6358767
[protein shifts and the immunoglobulin and immune complex content of the blood serum or tropical malaria patients in the socialist republic of vietnam].		1983	6358821
rapid action of qinghaosu and related drugs on incorporation of [3h]isoleucine by plasmodium falciparum in vitro.	using the incorporation of [3h]isoleucine into acid-insoluble products as an index of protein-synthetic activity, it was shown that qinghaosu and two related drugs had a rapid effect on this process in human erythrocytes infected with plasmodium falciparum in vitro. inhibition could be seen 1 hr or less after addition of the drugs at concentrations from 5 mumole/1. to 50 nmole/1. it is recommended that the effects of these drugs be studied in cell-free protein-synthetic systems.	1983	6351863
childhood malaria in edinburgh 1961-1982.	forty one cases of malaria in children less than 15 years of age were identified from the records of edinburgh hospitals between 1961 and 1982. annually children constitute 10 to 20 per cent of all cases of malaria in scotland and since 1971 at least one case has been admitted to an edinburgh paediatric unit every year. non-immune children visiting relatives in the indian sub-continent are the largest group at risk. prophylaxis was not usually taken by the patients visiting asia and the cases fr ...	1983	6359413
clinical management of chloroquine-resistant plasmodium falciparum malaria in southeast asia.		1983	6359592
clinical management of acute falciparum malaria in tanzania.		1983	6359593
fansidar resistant plasmodium falciparum infection in surinam.	the first cases of fansidar resistant plasmodium falciparum infection in surinam are reported after chloroquine-resistance was reported in 1972. the resistant cases were suspected by physicians and confirmed after performing the 35-day extended standard who 7-day in vivo-test. the distribution of drug resistant p. falciparum in surinam is presented. the problem that drug resistance causes in the malaria eradication program in surinam is discussed.	1983	6359597
characterization of the humoral immune response in plasmodium falciparum malaria. i. estimation of antibodies to p. falciparum or human erythrocytes by means of microelisa.	an enzyme linked immunosorbent assay (elisa) has been developed to estimate disease related antibodies in sera from malaria patients or individuals living in malaria endemic areas. as antigen, percoll enriched fractions (mainly late trophozoites, schizonts) from plasmodium falciparum in vitro cultures were used. an elisa with ghosts from normal human red blood cells (rbc) was performed in parallel. one hundred and seventy-five sera were tested for their reactivity with either one of the two anti ...	1983	6352102
immunity to malarial antigens on the surface of plasmodium falciparum-infected erythrocytes.	an indirect immunofluorescence test with fresh non-fixed infected blood as antigen was used to show that antibody in human sera from the gambia recognized antigens on the surface of plasmodium falciparum-infected human erythrocytes. surface immunofluorescence was detected on 90% of erythrocytes infected with trophozoites and schizonts produced in continuous culture of isolates from the gambia (fcr 3/k+), brazil and thailand. fluorescence was equally strong with a gambian parasite clone (fcr 3/k- ...	1983	6353958
characterization of the humoral immune response in plasmodium falciparum malaria. ii. igg subclass levels of anti-p. falciparum antibodies in different sera.	the igg subclass levels of anti-plasmodium falciparum antibodies in human sera were determined in elisa with monoclonal mouse antibodies specific for the human igg subclasses as analytical reagents. the parasite antigen was a trophozoite/schizont enriched preparation of in vitro cultivated p. falciparum. serum samples were from swedish malaria patients and adult liberians. parasite specific antibodies were found in all four subclasses. relatively elevated levels of igg1 antibodies were found bot ...	1983	6352103
plasmodium falciparum: effect of time in continuous culture on binding to human endothelial cells and amelanotic melanoma cells.	an in vitro correlate of the binding in vivo of plasmodium falciparum-infected erythrocytes to capillary and venular endothelium, using cultured human endothelial cells and amelanotic melanoma cells, was previously developed. the effects of different times in continuous culture on binding of erythrocytes infected with nine different isolates of p. falciparum is now reported. four isolates, which bound at the time they were first tested, rapidly lost the ability to bind after 26-43 days in cultur ...	1983	6352321
seroepidemiology of malaria in karnataka state: longitudinal study of a population from an area with high incidence at kolar, south india.	serologic methods have considerable value in epidemiologic surveillance of malaria. antigens prepared from p falciparum cultured in vitro have been found to be sensitive and to a certain extent specific in the ifa test to detect malarial antibodies in the sera from a population continuously exposed to p falciparum and plasmodium vivax infections [1]. however, it is necessary to assess the serologic data against the results of conventional examination of peripheral blood smears in monitoring the ...	1983	6352829
synchronization of plasmodium falciparum in continuous in vitro culture: use of colchicine.	cultures of plasmodium falciparum with parasitemias of 3-5% were exposed to 4 mm colchicine for 24 hours. synchrony was observed 48 hours after treatment, and the cultures remained synchronous for more than two replicative cycles. the percentage of ring stage parasites reached peaks of over 90% at 72 and 120 hours. the percentage of schizonts reached a peak of 70% at 144 hours. parasitemias in both colchicine-treated and untreated control cultures reached peaks of over 20% 120 hours after colchi ...	1983	6359912
chloroquine inhibits the degradation of endocytic vesicles in human malaria parasites.		1983	6360383
a phase i clinical trial of mefloquine in brazilian male subjects.	a double-blind, randomized phase i clinical trial was carried out to compare mefloquine with sulfadoxine-pyrimethamine for safety and tolerance. twenty adult male brazilian subjects from areas endemic for malaria were studied for a period of 66 days, which included 2 days of basal studies and a 63-day follow-up after drug administration. subjects received either mefloquine, given as a single oral dose of 1000 mg (4 x 250-mg tablets) or sulfadoxine-pyrimethamine (2 tablets, each containing 500 mg ...	1983	6360400
effects of qinghaosu and chloroquine on the ultrastructure of the erythrocytic stage of p. falciparum in continuous cultivation in vitro.		1983	6353081
treatment of plasmodium falciparum malaria with a combination of amodiaquine and tetracycline in central thailand.	a combination of the drugs amodiaquine and tetracycline was used in a clinical trial at phrabuddhabat hospital in central thailand for treating plasmodium falciparum malaria. of the 51 patients who completed the 28-day follow-up, 49 (96%) were cured; in two cases the parasitaemia was cleared within seven days of initial therapy but returned within 28 days (ri response). only one patient experienced a mild and transient side effect of nausea. the treatment regimen was cheap and the drugs are read ...	1983	6353687
sickle cell trait, malaria and anaemia in pregnant zambian women.	in a sample of 424 pregnant zambian women a series of tests was carried out: sickle cell test, haemoglobin estimation and screening of a thick blood smear for malarial parasites. more anaemia was found in the primigravidae than in the multigravidae. the haemoglobin level was found to be lower with primigravidity and, independently of this gravidity effect, also with malaria. taking into account the higher malaria frequency in primigravidae, this group must be considered as a high risk group for ...	1983	6353689
[malaria vaccines in development].		1983	6355868
in vitro culture as a source of plasmodium falciparum antigen in micro-elisa in malaria.		1983	6360860
platelet secretory activities in acute malaria (plasmodium falciparum) infection.	during acute plasmodium falciparum infection in man, plasma concentrations of platelet-specific proteins, beta-thromboglobulin (beta tg) and platelet factor 4 (pf4) were significantly elevated. for beta tg, the mean concentration was 136.24 +/- 71.58 ng/ml in patients, and 50.53 +/- 25.42 ng/ml in control subjects (t = 5.3794; p = 0.0001), while for pf4 mean values were, respectively, 75.35 +/- 23.09 and 18.64 +/- 13.42 ng/ml (t = -6.0897; p less than 0.0001). platelet ldh loss in vitro in respo ...	1983	6192658
regulation of the immune response in plasmodium falciparum malaria. ii. antigen specific proliferative responses in vitro.	the antigen-induced dna synthesis in vitro in lymphocytes from patients with acute plasmodium falciparum malaria was investigated. the patients and healthy controls from sweden or colombia were the same as those studied in the accompanying paper (troye-blomberg et al., 1983). the malarial antigens used were sonicated membrane preparations or purified and concentrated supernatants from in vitro cultures of p. falciparum; similar preparations derived from normal human erythrocytes served as contro ...	1983	6192953
[plasmodium falciparum malaria resistant to 4-aminoquinolines, contracted in east africa].		1983	6225105
[effect of chloroquine on different stages of asexual forms of plasmodium falciparum in culture].		1983	6225305
folate antagonists. 20. synthesis and antitumor and antimalarial properties of trimetrexate and related 6-[(phenylamino)methyl]-2,4-quinazolinediamines.	a series of 6-[(arylamino)methyl]-2,4-quinazolinediamines have been prepared by catalytic hydrogenation of the requisite 2,4-diamino-6-quinazolinecarbonitriles in the presence of the appropriate benzenamine. formylation, acetylation, and nitrosation provided n omega derivatives of these compounds. a variety of the compounds exhibited potent antimalarial, antibacterial, and antitumor activity. in particular, 5-methyl-6-[[(3,4,5-trimethoxyphenyl)-amino]methyl]-2, 4-quinazolinediamine (trimetrexate ...	1983	6227747
plasmodium falciparum parasites induce interferon production in human peripheral blood 'null' cells in vitro.	human peripheral blood mononuclear cells were found to produce interferon (ifn) when stimulated by free p. falciparum parasites in vitro. on the other hand parasite-infected, intact erythrocytes were unable to induce ifn synthesis. when the ifn was characterized according to sensitivity to anti-ifn-alpha antibodies and ph 2 treatment it was found to consist of ifn-alpha. cell fractionation procedures and analysis of each cell fraction with regard to natural killer (nk) cell activity and ifn-prod ...	1983	6302627
cloning and characterisation of the rrna genes from the human malaria parasite plasmodium falciparum.	ribosomal dna fragments from the human malaria parasite plasmodium falciparum have been cloned and analysed in detail. restriction mapping shows that the cloned fragments are different. however, they do have some similarities, in particular a small stretch of a+t-rich dna located between the small and large subunit rrna genes. a small rrna gene has been mapped to this a+t-rich region. copy number analysis reveals that each fragment is represented approximately 4 times in the genome, and implies ...	1983	6324096
immune-mediated thrombocytopenia of malaria.	thrombocytopenia frequently complicates malarial infections but the mechanism has not been elucidated. we studied 28 patients with malarial infections and noted that 16 of 17 thrombocytopenic patients had elevated levels of platelet-associated igg (paigg). in all thrombocytopenic patients studied, the level of paigg returned to normal as the platelet count rose to normal levels. to study the mechanism of the elevated platelet-bound igg, igg and f(ab')2 from patients with recurrent plasmodium fal ...	1983	6220030
plasmodium falciparum: assessment of in vitro growth by [3h]hypoxanthine incorporation.	to evaluate rapidly plasmodium falciparum growth in vitro, [3h]hypoxanthine was added to parasite microcultures and radioisotope incorporation was measured. when culture parameters were carefully controlled, [3h]hypoxanthine incorporation was proportional to the number of parasitized erythrocytes present. factors affecting [3h]hypoxanthine incorporation included initial parasitemia, duration of culture, duration of radioisotope pulse, parasite stage, concentration of uninfected erythrocytes, the ...	1983	6337059
plasmodium falciparum: one-step growth in a semi-defined medium and the stimulatory effect of human seric lipoproteins and liposomes.	the ring stages of plasmodium falciparum within red blood cells cultured with complete medium stop growing when transferred to a basic medium containing rpmi plus fatty acid-free bovine serum albumin and dialyzable factors from human serum. growth and multiplication can be partially restored by the addition of lipoprotein fractions prepared from human serum. no specificity was observed with subclasses of lipoproteins. synthetic liposomes containing lecithin, oleic acid, and cholesterol mimic the ...	1983	6337060
a rabbit--in vitro system to evaluate drug action against plasmodium falciparum.	a rabbit-in vitro model system is described which can determine the activity of anti-malarial drugs against erythrocytic stages of plasmodium falciparum. serum samples, collected from rabbits at various times after drug administration, wee incubated with synchronized ring form parasites using the microtest system. the extent to which the presence of drugs in the serum inhibited parasite growth was usually determined after 32 to 40 hours of incubation. anti-malarial activity was observed in sera ...	1983	6222522
glucose-6-phosphate dehydrogenase deficiency inhibits in vitro growth of plasmodium falciparum.	glucose-6-phosphate dehydrogenase (g6pd; ec 1.1.1.49)-deficient red blood cells from male hemizygotes and female heterozygotes from the island of sardinia were studied for their ability to support growth in vitro of the malaria-causing organism plasmodium falciparum. parasite growth was approximately one-third of normal in both hemi- and heterozygotes for g6pd deficiency. in sardinians with the beta 0-thalassemia trait, parasite growth was normal except when g6pd deficiency occurred together wit ...	1983	6337374
[malaria imported into the crimea].		1983	6226857
preliminary field trial of a radioimmunoassay for the diagnosis of malaria.	a radioimmunoassay (ria) has been developed for the detection of plasmodium falciparum in infected blood. the assay is based on the ability of solubilized, infected red blood cells (rbc) (p. falciparum "antigen") to combine with anti-p. falciparum antibodies and thus prevent the subsequent interaction of the latter with "antigen"-coated microtiter plates. a preliminary trial was carried out in thailand to determine the usefulness of the ria for the immunodiagnosis of malaria. blood samples from ...	1983	6337515
deficiency of con a-induced suppressor cell activity in peripheral blood mononuclear cells from thai adults naturally infected with plasmodium falciparum and plasmodium vivax.	con a-pretreated mononuclear (mnc) cells from thai adults with naturally acquired p. falciparum or p. vivax malaria were significantly less effective in suppressing the responsiveness of autologous or normal allogeneic responder cells to mitogenic lectins or allogenic stimulator cells than pretreated cells from healthy donors. serial studies of three patients demonstrated that reduced suppressor cell activity was present early in malaria infection but returned to normal soon after treatment. the ...	1983	6226919
[p. falciparum and p. malariae malaria complicated by pulmonary edema with disseminated intravascular coagulation].		1983	6228898
comparative clinical and experimental study on the pathogenesis of cerebral malaria.		1983	6337773
ribosomal dna sequences detected in malaria parasites by cytochemical hybridization.	a procedure in which fluorochrome-labelled rna is hybridized in situ to homologous dna sequences was used to investigate the possible application of this method to the human malaria parasite plasmodium falciparum. rhodamine-labelled ribosomal rna stained the nuclei of the parasites after cytochemical hybridization. this result demonstrates that ribosomal rna genes can be visualised. it was estimated that the hybridization efficiency was greater than 40%.	1983	6230132
susceptibility to invasion by plasmodium falciparum of some human erythrocytes carrying rare blood group antigens.	tn and cad erythrocytes which carry unusual carbohydrate moieties attached to glycophorin a and b, the main red cell membrane sialoglycoproteins, resist invasion by the malarial parasite plasmodium falciparum. tn red cells are defective in sialic acid and galactose whereas cad erythrocytes are characterized by a normal sialic acid content but the presence of an additional n-acetylgalactosamine residue attached to each sialotetrasaccharide chain o-glycosidically linked to glycophorin a and b. hom ...	1983	6200133
serological cross-reaction between high molecular weight proteins synthesized in blood schizonts of plasmodium yoelii, plasmodium chabaudi and plasmodium falciparum.	a 230 000 molecular weight (mw) plasmodium yoelii protein, a 250 000 mw p. chabaudi protein and a 195 000 mw p. falciparum protein, identified using monoclonal antibodies, have similar characteristics, and have been implicated as protective antigens. in this study the serological relationship between these proteins was investigated by western transfer analysis. the monoclonal antibodies specific for each of the high molecular weight proteins did not cross-react with antigens of the other two par ...	1983	6201740
separation and concentration of schizonts of plasmodium falciparum by percoll gradients.	a technique for the separation of schizonts of plasmodium falciparum is described. the different stages of the asexual cell cycle of the parasite were positioned according to their density in a continuous gradient of percoll. young trophozoites coincided with erythrocytes in a broad band corresponding to densities from 1.075 to 1.100 g/ml, whereas schizonts were concentrated at a density approximating 1.062 g/ml. the viability of the parasites was unimpaired by this procedure. young trophozoites ...	1983	6313915
expression of plasmodium falciparum blood-stage antigens in escherichia coli: detection with antibodies from immune humans.	many proteins produced by blood stages of the malaria parasite plasmodium falciparum are natural immunogens in man. as an approach to determining which of these are relevant to protective immunity we have constructed an expression library of p. falciparum cdna sequences, cloned in escherichia coli. the cdna sequences were inserted into the beta-galactosidase gene of an ampicillin-resistant derivative of the temperature-sensitive lysogenic bacteriophage lambda gt11. about 5% of the resulting clon ...	1983	6304737
stage-dependent effects of chloroquine on plasmodium falciparum in vitro.	the erythrocytic developmental cycle of plasmodium falciparum can be conveniently divided into the ring, trophozoite, and schizont stages based on morphology and metabolism. using highly synchronous cultures of p. falciparum, considerable variation was demonstrated among these stages in sensitivity to chloroquine. the effects of timed, sequential exposure to several clinically relevant concentrations of chloroquine were monitored by three techniques: morphological analysis, changes in the rate o ...	1983	6198514
[plasmodium falciparum malaria acquired in kenya with type ii or type iii resistance to amino-4-quinolines].	the authors report a case of plasmodium falciparum malaria acquired in kenya by a french tourist under correct chloroquine prophylaxis. she recovered under quinine and a sulfadoxine-pyrimethamine association. this is a new case of high level resistance (r ii or r iii) of plasmodium falciparum to amino-4-quinolines recognized in east africa. malarial chemoprophylaxis recommended until now for this area may need to be reviewed.	1983	6306815
human serum proteins indicative for the nutritional status and serum proteinase inhibitors in uncomplicated falciparum malaria.	the serum proteins supposed to be indicative of the nutritional status, albumin, prealbumin and transferrin, as well as the serum proteinase inhibitors alpha 1-protease inhibitor (alpha 1-antichymotrypsin (ach) and alpha 2-macroglobulin (alpha 2m) were measured in 14 thai males suffering from uncomplicated falciparum malaria on the day of admission and after treatment with mefloquin on the 2nd, 28th and 63rd day. the same serum proteins had been determined from 31 healthy thai males. upon admiss ...	1983	6198795
[etiological factors in burkitt's disease].	different aetiological factors of burkitt's disease, or burkitt's lymphoma (bl) are considered in an analytical, then synthetical point of view, according to present admitted facts. epidemiologic data are recalled in order to assign a place to the disease. relations with epstein-barr virus (e.b.v.) are well-known by comparative pathology (connections between animal tumors and herpetic virus), virologic and serologic studies; the role of e.b.v. is based on the presence of viral genomas and nuclea ...	1983	6310311
characterization of an s antigen synthesized by several isolates of plasmodium falciparum.	the s antigen of a papua new guinean isolate of plasmodium falciparum was identified by immunoblotting as the dominant antigen in culture supernatants. an antigen identical in molecular weight (mr 220,000), isoelectric point (pi 4.2), and immunoreactivity with sera from individuals exposed to malaria was expressed by four papua new guinean isolates and one isolate of unknown origin. the mr 220,000 antigen was not detected in culture supernatants derived from two isolates from thailand and one fr ...	1983	6195663
serum alpha-1 antichymotrypsin is a possible growth inhibitor of plasmodium falciparum.	serum protease inhibitors were determined in paired sera from 7 patients with cerebral malaria and 2 patients with acute malaria showing high and low growth inhibition activity in the initial and follow-up sera respectively. alpha-1 antichymotrypsin and alpha-1 antitrypsin but not alpha-2 macroglobulin showed direct correlation with the growth inhibition activity. when alpha-1 antitrypsin was deliberately added to the malarial culture no growth inhibition occurred indicating that the alpha-1 ant ...	1983	6197759
malaria control and primary health care.		1983	6136833
changes in malaria incidence after mass drug administration in nicaragua.	mass drug administration (mda) in 1981 reduced the incidence rates of both plasmodium vivax and p falciparum infection in nicaragua. impact on p vivax cases lasted for four months and on p falciparum for seven. subtherapeutic primaquine doses, the shorter extrinsic cycle of p vivax in the insect vector, and the timing of mda at a high-transmission period of the year may explain the limited effects of the campaign. positive results of the anti-malaria campaign included improvements in case-findin ...	1983	6136655
failure of chloroquine prophylaxis in plasmodium falciparum in zaire.		1983	6135019
[epidemiology, diagnosis and prevention of malaria].		1983	6138047
the role of cell-mediated immune responses in resistance to malaria, with special reference to oxidant stress.	asexual blood forms of malaria parasites are microaerophilic and sensitive to oxidant stress. plasmodium falciparum and some other species of malaria parasites undergo schizogony attached to endothelial cells of postcapillary venules, where oxygen tensions are low. acquired immune responses to all forms of malaria parasites so far investigated are thymus dependent. animals deprived of t lymphocytes do not recover from the infections and cannot be immunized against malaria parasites. in contrast, ...	1983	6100538
a labour-saving method for the in vitro culture of plasmodium falciparum.	the in vitro cultivation of plasmodium falciparum requires at least daily changes of medium (trager and jensen, 1976). addition of 50 mg per litre of hypoxanthine to medium rpmi 1640 permits to postpone the change of medium for up to 72 hours. a single subculture step is required to remove unlabelled hypoxanthine prior to the use of the cultured material in 3h-hypoxanthine incorporation assays. the method constitutes a considerable saving of time and medium.	1983	6134451
surface alterations of erythrocytes in plasmodium falciparum malaria. antigenic variation, antigenic diversity, and the role of the spleen.	the surface of erythrocytes infected with late developmental stages of plasmodium falciparum is profoundly altered and new antigenic determinants can be detected by surface immunofluorescence using immune squirrel monkey serum. the expression of these parasite-specific antigenic determinants on the surface of the host erythrocyte can be modulated by the presence or absence of the spleen and by immune pressure. an antigenic switch occurred when a cloned population of the ugandan palo alto strain ...	1983	6187885
quinine and quinidine: a comparison of ekg effects during the treatment of malaria.	we recorded electrocardiograms from 31 patients receiving quinine and 14 patients receiving quinidine for the treatment of plasmodium falciparum malaria. despite plasma quinine concentrations of up to 20 mg/l, there was no evidence of cardiotoxicity. qt prolongation was considerably greater in the quinidine-treated patients. the mean ratio of change in corrected qt interval to change in plasma concentration (delta qtc%/delta cq) was 3.2% . mg-1 . l-1 for quinidine, compared to 0.74% . mg-1 . l-1 ...	1983	6188885
circumsporozoite proteins of malaria parasites contain a single immunodominant region with two or more identical epitopes.	we have used panels of monoclonal antibodies to circumsporozoite (cs) proteins of plasmodium falciparium, p. vivax, and p. knowlesi to determine the number of topographically independent epitopes of these antigens. the results of competition binding assays indicated that single regions of the cs molecules were recognized by the homologous monoclonal antibodies. competition binding assays were also used to study the specificity of antibodies contained in the sera of humans and monkeys that had de ...	1983	6189951
role of internal domains of glycophorin in plasmodium falciparum invasion of human erythrocytes.	human erythrocyte glycophorin, a putative receptor to plasmodium falciparum malaria parasites, was studied in terms of its structural domains involved in mediating invasion. these domains were isolated from purified glycophorin a and from supernatants and membranes obtained from protease-treated erythrocytes. they were tested for invasion blocking capacity by using an in vitro assay system. the role of carbohydrate-rich domains was assessed with the following compounds: (i) sialoglycopeptides re ...	1983	6194114
differential effect of immunoglobulin on the in vitro growth of several isolates of plasmodium falciparum.	immunoglobulin isolated from the sera of individuals living in a malarious area of papua new guinea was tested for an effect on the growth in vitro of four isolates of plasmodium falciparum, three from papua new guinea and one from thailand. the papua new guinea isolates were inhibited to the same degree by individual immunoglobulin preparations, and inhibition varied from 0 to 98% (assessed by a radioisotopic readout). immunoglobulin preparations which inhibited the papua new guinea isolates ca ...	1983	6188695
immunological cross-reactivity of the histidine-rich protein of plasmodium lophurae and the knob protein of plasmodium falciparum.	rabbits were immunized with the histidine-rich protein (hrp) of the avian malaria parasite, plasmodium lophurae. the anti-hrp immunoprecipitated the knob protein (kp) from extracts of the human parasite, plasmodium falciparum. the anti-hrp did not react with any antigens of a laboratory-derived strain of p. falciparum (k-) that does not form knobs. antisera raised against a membrane-enriched fraction of p. falciparum-infected erythrocytes as well as sera from humans exposed to p. falciparum infe ...	1983	6189987
reactions of toxoplasma antibodies against three malarial antigens.		1983	6198408
[production of circulating interferon in human malaria].	the presence of an interferon-like activity inhibiting the cytopathic effect of vesicular stomatitis virus was studied in 216 sera from 100 patients with p. falciparum (67 cases), p. vivax (16), p. ovale (13), p. malariae (4) infections. 87% of patients were found positive on one or more occasions. the prevalence of interferon-like activity was similar in all 4 species. titers varied between 20 to 320 u/ml and were found to be higher in europeans experiencing a primary attack of malaria (mean = ...	1983	6188547
free oxygen radicals in malaria.		1983	6130362
quinine in chloroquine-resistant falciparum malaria.		1983	6131172
quinine containing drinks may hamper diagnosis of malaria.		1983	6131250
why not proguanil in malaria prophylaxis?		1983	6131328
possible case of riii chloroquine-resistant malaria from east africa.		1983	6132122
mefloquine resistance of falciparum malaria from tanzania enhanced by treatment.		1983	6132124
in-vivo and in-vitro assessment of chloroquine-resistant plasmodium falciparum malaria in zanzibar.	a population-based field study was conducted in zanzibar town, zanzibar, tanzania, to assess the in-vivo and in-vitro susceptibility to chloroquine of plasmodium falciparum. single-dose therapy with chloroquine (10 mg base/kg) failed to clear parasitaemia in 11 of 22 (50%) treated subjects, and a standard therapeutic regimen of chloroquine (25 mg base/kg) failed to clear parasitaemia in 11 of 32 (34%) treated subjects. concurrent in-vitro testing by the rieckmann micromethod showed that 8 of 12 ...	1983	6133056
blood samples and chloroquine assay.		1983	6134030
chloroquine-resistant plasmodium falciparum in zanzibar.		1983	6134032