| travel medicine--prevention based on epidemiological data. | in travel medicine efforts should be concentrated on preventive measures that are necessary, and travellers should be spared the side effects, costs and stress of superfluous measures. excess mortality abroad is mainly due to traffic and swimming accidents, indicating the need for appropriate control strategies. the morbidity in travellers to developing countries is high, and is primarily due to traveller's diarrhoea. as prophylaxis is ineffective or unrealistic, and as travellers often need fas ... | 1991 | 1887461 |
| feeding behaviour and sporozoite ejection by infected anopheles stephensi. | anopheles stephensi mosquitoes infected with plasmodium falciparum sporozoites were allowed to feed individually through fresh whole thickness mouse skin. more sporozoites were ejected into the skin in clusters than into the blood. deposition of sporozoites in the blood was an infrequent occurrence and always coincided with ejection of these stages into the skin--perhaps a spill-over effect. the number of probes before feeding (median 4.5) was not correlated with the sporozoite inoculum (median ... | 1991 | 1887464 |
| permethrin-impregnated curtains in malaria control. | the impact of permethrin-impregnated curtains on the incidence of malaria episodes, parasitaemia and splenomegaly was assessed during a 22 month period in 2 groups of children aged 0.5-6 years. one group lived in houses where permethrin-impregnated curtains had been installed, the other group lived in houses without curtains. a significant reduction of incidence of malaria episodes, mean parasite density, parasite prevalence and splenomegaly was consistently observed in the intervention group to ... | 1991 | 1887465 |
| comparison of two simple methods for determining malaria parasite density. | two simple methods for determining malaria parasite density which require only the examination of a thick blood film were compared with a more accurate method which involves determination of the red blood cell count and measurement of the level of infection in red blood cells by examination of a thin blood film. in one method, the number of parasites present per white blood cell is counted and this figure multiplied by 8000 (an average white blood cell count per microliter) to give the parasite ... | 1991 | 1887466 |
| the metabolic response to rapid intravenous glucose injection in acute falciparum malaria. | because hypoglycaemia is common in severe malaria, intravenous glucose is often given empirically to patients on admission to hospital. to investigate the metabolic response to rapid glucose injection in acute malaria, 50 ml of 50% w/v (25 g) dextrose was given over 5 min to 10 adult patients (7 males, 3 females; mean age 30 years) with acute falciparum malaria. five patients with severe infections were studied between doses of intravenous quinine; 5 cases were uncomplicated and previously untre ... | 1991 | 1887467 |
| the changing pattern of plasmodium falciparum susceptibility to chloroquine but not to mefloquine in a mesoendemic area of somalia. | the response of plasmodium falciparum to chloroquine and mefloquine was investigated in a mesoendemic area of somalia from 1986 to 1989. serial in vivo field tests for chloroquine sensitivity were performed and the sensitivity in vitro to chloroquine and mefloquine was evaluated using the standard who in vitro microtest. chloroquine treatment in vivo (25 mg base/kg body weight) resulted in parasite clearance in all patients within 7 d (s/ri) in 1986, while 17%, 19% and 30% rii/riii responses wer ... | 1991 | 1887468 |
| reversal of chloroquine resistance with cyproheptadine in 'wild' strains of plasmodium falciparum. | | 1991 | 1887469 |
| in vivo-in vitro test for chloroquine potentiation by cyproheptadine against plasmodium falciparum. | | 1991 | 1887470 |
| absence of antimalarial activity or interaction with mefloquine enantiomers in vitro of the main human metabolite of mefloquine. | | 1991 | 1887471 |
| comparative effectiveness of artemisinin suppositories and oral quinine in children with acute falciparum malaria. | | 1991 | 1887472 |
| high antibody responses in rabbits immunized with influenza virus iscoms containing a repeated sequence of the plasmodium falciparum antigen pf155/resa. | immunostimulating complexes (iscoms) are spherical structures where immunogens are presented as multimers in a matrix of the adjuvant quil a. iscoms have been shown to enhance the immunogenicity of several antigens important to both human and veterinary vaccine development. we have coupled a fusion protein, designated zz-m2, comprising eight copies of the c-terminal repeat subunit eenv of the plasmodium falciparum blood-stage antigen pf155/resa and two igg-binding domains of staphylococcal prote ... | 1991 | 1887676 |
| the chemotherapy of rodent malaria. xlvi. reversal of mefloquine resistance in rodent plasmodium. | multiple drug resistance in plasmodium falciparum is already showing evidence of extending to mefloquine, which at present is one of the few alternative antimalarials for the prevention or treatment of infection with such parasites. neither verapamil nor cyproheptadine, which reverse chloroquine (cq) resistance in p. falciparum and in rodent malaria parasites, reverse resistance to mefloquine (mef) in the mef-resistant ns/1100 line of p. yoelii ssp. ns. on the other hand, such resistance is clea ... | 1991 | 1888220 |
| mefloquine pharmacokinetics and resistance in children with acute falciparum malaria. | the pharmacokinetic properties of mefloquine hydrochloride (15 mg base kg -1) were studied in 12 karen children (five girls, seven boys) aged between 5 and 10 years presenting with uncomplicated falciparum malaria. the drug was well tolerated. mean (s.d.) peak blood drug concentrations of 2031 (831) ng ml-1 were reached in a median of 8 (range 6-24) h. mean (s.d.) estimates for oral clearance and mean residence time were 0.52 (0.27) ml min -1 kg -1 and 15.3 (4.7) days, respectively. these values ... | 1991 | 1888626 |
| [the intensive medical treatment of severe malaria tropica]. | | 1991 | 1889358 |
| lack of h-2 restriction of the plasmodium falciparum (nanp) sequence as multiple antigen peptide. | the major surface antigen of malaria sporozoites, the circumsporozoite protein, contains a region of tandem amino acid repeats, which in the case of the human malaria parasite plasmodium falciparum, consist of four amino acids asn-ala-asn-pro (nanp) repeated up to about 40 times. this repetitive sequence has been considered as the basis for the development of subunit vaccines against p. falciparum malaria. we and others had previously shown that synthetic and recombinant nanp peptides were immun ... | 1991 | 1889465 |
| interaction of the 140/130/110 kda rhoptry protein complex of plasmodium falciparum with the erythrocyte membrane and liposomes. | during plasmodium falciparum merozoite invasion into human and mouse erythrocytes, a 110-kda rhoptry protein is secreted from the organelle into the erythrocyte membrane. in the present study our interest was to examine the interaction of rhoptry proteins of p. falciparum with the erythrocyte membrane. it was observed that the complex of rhoptry proteins of 140/130/110 kda bind directly to a trypsin sensitive site on intact mouse erythrocytes, and not human, saimiri, or other erythrocytes. howev ... | 1991 | 1889471 |
| enhancement of the antimalarial effect of chloroquine on drug-resistant parasite strains--a critical examination of the reversal of multidrug resistance. | | 1991 | 1889476 |
| proteins of unusual sequence composition from the malarial parasite plasmodium falciparum. | | 1991 | 1889675 |
| molecular probe for identification of trichomonas vaginalis dna. | trichomoniasis is one of the most widespread sexually transmitted diseases in the world. diagnosis can be achieved by several methods, such as direct microscopic observation of vaginal discharge, cell culture, and immunological techniques. a 2.3-kb trichomonas vaginalis dna fragment present in strains from diverse geographic areas was cloned and used as a probe to detect t. vaginalis dna in vaginal discharge by a dot blot hybridization technique. this probe was specific for t. vaginalis dna. it ... | 1991 | 1890171 |
| protection against plasmodium falciparum infection in children with hemoglobin s. | | 1991 | 1891293 |
| haemolysis of infected erythrocytes--a trigger for formation of plasmodium falciparum gametocytes? | | 1991 | 1891456 |
| the dynamics of drug resistance in plasmodium falciparum. | drug resistance of plasmodium falciparum is not a recent phenomenon, but it became a major problem when the parasite became resistant to chloroquine, the cheapest and initially the most effective antimalarial compound that could be used for treatment and suppression. in some areas this problem is compounded by resistance to the first line of alternative drugs, and rapid loss of sensitivity to the next line. the dynamics of drug resistance are regulated mainly by drug related selection pressure a ... | 1991 | 1891480 |
| [plasmodium falciparum resistant to sulfadoxine/pyrimethamine in senegal]. | in 1983, the first african cases of malaria due to plasmodium falciparum resistant to sulfadoxine/pyrimethamine, were described. currently, this resistance is frequently found in kenya and tanzania. it has also been described in other african countries. a young spanish woman contracted plasmodium falciparum malaria in senegal and was treated in our hospital with sulfadoxine/pyrimethamine. fever and symptoms disappear within two days. the thick smears taken on the eighth and thirteenth days of tr ... | 1991 | 1893008 |
| adverse reactions to sulfa drugs: implications for malaria chemotherapy. | national adverse drug reaction registers in sweden and the united kingdom provided data on the type, severity and frequency of reported adverse reactions attributed to sulfa drugs. reactions to the ten principal drugs were examined in terms of their half-lives and usual indications for use. of 8339 reactions reported between 1968 and 1988, 1272 (15%) were blood dyscrasias, 3737 (45%) were skin disorders, and 578 (7%) involved the liver. these side-effects occurred with all types of sulfa drugs i ... | 1991 | 1893504 |
| ability of recombinant or native proteins to protect monkeys against heterologous challenge with plasmodium falciparum. | to circumvent problems associated with polymorphic vaccine candidates for plasmodium falciparum malaria, we evaluated recombinant proteins representing sequences from relatively high conserved regions of the precursor to the major merozoite surface proteins, gp190, for their ability to protect saimiri monkeys against malaria challenge. recombinant proteins represented amino acid residues 147 to 321 (p190-1) or 147 to 321 and 1060 to 1195 (p190-3), and their efficacy was compared with that of nat ... | 1991 | 1894356 |
| can in vivo surveys on the chemosensitivity of plasmodium falciparum still be done in tropical africa? | | 1991 | 1894952 |
| pentoxifylline in cerebral malaria. | | 1991 | 1894953 |
| deet and permethrin as protectants against malaria-infected and uninfected anopheles stephensi mosquitoes. | deet and permethrin were evaluated as protectants against plasmodium falciparum-infected, p. berghei-infected and uninfected anopheles stephensi mosquitoes. deet 50% effective dose (ed50) values were 3.2 micrograms/cm2 for p. falciparum-infected and 1.9 micrograms/cm2 for uninfected mosquitoes; permethrin values were 0.5 micrograms/cm2 and 0.6 micrograms/cm2, respectively. deet ed50 values were 2.3 micrograms/cm2 for p. berghei-infected and 1.3 micrograms/cm2 for uninfected mosquitoes; the perme ... | 1991 | 1895090 |
| isolated cerebellar syndrome: an atypical form of cerebral malaria. | | 1991 | 1895136 |
| [plasmodium falciparum travels by train from ethiopia to djibouti]. | to investigate the role of the djibouti-ethiopian railway as a potential vehicle for inter-regional spread of malaria vectors and malaria parasites, we performed a double-sided study, both entomological and parasitological, during november 1989, at the frontier post of guelile where the trains from ethiopia enter the republic of djibouti. no malaria-transmitting mosquitoes were collected either from the daily passenger train or from the weekly vegetables train. one hundred and five passengers en ... | 1991 | 1895918 |
| antimalarial activity of some natural peroxides. | | 1991 | 1896527 |
| cloning and expression of genomic dna sequences coding for putative erythrocyte membrane-associated antigens of plasmodium falciparum. | genomic dna fragments of plasmodium falciparum generated by mung bean nuclease digestion were cloned in the lambda expression vector lambda jk2. the resulting library was screened with a rabbit antiserum raised against purified membranes of p. falciparum-infected erythrocytes and with a serum pool from immune humans from an endemic area of liberia. positive clones were rescreened with a series of human and monkey sera. twelve selected clones were analysed in detail. four of them corresponded to ... | 1991 | 1896607 |
| renal failure is a common complication in non-immune europeans with plasmodium falciparum malaria. | renal failure in malaria appears to be a complication less well known than anaemia and cerebral malaria. thirty-one non-immune patients treated for plasmodium falciparum malaria at hannover medical school were reviewed. nine patients (29%) had acute renal failure, seven of whom required dialysis, and five patients needed mechanical ventilation. cerebral symptoms were seen in nine patients, and three of the patients died. in a second series, information about patients who died of malaria in germa ... | 1991 | 1896768 |
| low doses of quinine during a short time period are effective for clearance of plasmodium falciparum in asymptomatic children in guinea bissau. | asymptomatic children in guinea bissau were given 5 mg quinine per kg body weight two times daily for 5 days (n = 18) or 3 days (n = 20) for treatment of plasmodium falciparum. parasites disappeared within four days after initiation of treatment and remained absent during the first week afterwards. six children reported adverse reactions, mainly mild tinnitus which disappeared after termination of treatment. reduced doses of quinine for shorter treatment periods was effective in this study. furt ... | 1991 | 1896775 |
| malaria in wisconsin 1981-1989: a review of cases and update on chemoprophylaxis. | malaria continues to be a significant cause of travel related morbidity and mortality for us citizens. yet there have been no previous analyses of malaria cases reported in wisconsin. to provide timely information to wisconsin physicians, the authors present a review of reported malaria cases in wisconsin for the years 1981 through 1989, and an update of current center for disease control malaria chemoprophylaxis. | 1991 | 1897236 |
| human response to a malaria vaccine candidate antigen. | the plasmodium falciparum heat-shock protein 70 (pfhsp70) has been proposed as a potential candidate antigen for a malaria vaccine. in this study the human immune response to this antigen has been evaluated. enzyme-linked immunosorbent assays (elisa) were performed on serum samples collected from individuals during and after malarial infection. only 70% of falciparum malaria patients responded to this antigen during the natural course of infection and 54% of the recovered cases who had no parasi ... | 1991 | 1897303 |
| enhanced choline and rb+ transport in human erythrocytes infected with the malaria parasite plasmodium falciparum. | human erythrocytes infected in vitro with the malaria parasite plasmodium falciparum showed a markedly increased rate of choline influx compared with normal cells. choline transport into uninfected cells (cultured in parallel with infected cells) obeyed michaelis-menten kinetics (km approximately 11 microm). in malaria-parasite-infected cells there was an additional choline-transport component which failed to saturate at extracellular concentrations of up to 500 microm. this component was less s ... | 1991 | 1898345 |
| the role of t lymphocytes in immunity to plasmodium falciparum. enhancement of neutrophil-mediated parasite killing by lymphotoxin and ifn-gamma: comparisons with tumor necrosis factor effects. | human neutrophils were treated with ifn-gamma or lymphotoxin and their interaction with the asexual blood forms of plasmodium falciparum was studied by a radiometric assay and microscopy. the results showed that human neutrophils inhibited the growth of p. falciparum and killed the parasite via a phagocytic mechanism. the cytokines significantly augmented the neutrophil-mediated killing of the parasite. when compared with the effects of tnf-alpha similar results were seen although ifn-gamma and ... | 1991 | 1898962 |
| change of dosing regimen for malaria prophylaxis with mefloquine. | | 1991 | 1898981 |
| halofantrine hydrochloride--efficacy and safety in children with acute malaria. | thirty two children with symptomatic malaria due to p. vivax and p. falciparum infections were treated with three doses of halofantrine hydrochloride 8 mg/kg body weight every 6 hours. mean fever clearance was 30 hours (range 24-48 hours). no significant clinical or biochemical side effects were observed. symptoms cleared rapidly. halofantrine hydrochloride was found to be highly effective and appeared to have no side effects in children with acute malaria infections. | 1991 | 1900550 |
| [detection of homologous oncogene sequences in the genome of plasmodium falciparum]. | homologous sequences of the acute rna tumor virus oncogenes have been found to be highly conserved within vertebrates, insects and yeasts. in the present work, seven different oncogene dna sequences have been used as probes to search for homologous sequences in the dna of the protozoan plasmodium falciparum. both the v-fms v-ha ras probes hybridized p. falciparum dna. the oncogene study will allow an understanding of the biology of the parasite and particularly the host-parasite relationships wh ... | 1991 | 1900731 |
| protective immunity induced in aotus monkeys by recombinant sera proteins of plasmodium falciparum. | we describe the vaccination of panamanian monkeys (aotus sp.) with two recombinant blood stage antigens that each contain a portion of the n-terminal region of the sera (serine repeat antigen) protein of the malaria parasite plasmodium falciparum. we immunized with either a 262-amino-acid sera fragment (sera i) that contains amino acids 24 to 285 of the 989-amino-acid protein or a 483-amino-acid sera fragment (sera n) that contains amino acids 24 to 506 as part of a fusion protein with human gam ... | 1991 | 1900809 |
| the evolution of plasmodial stage-specific rrna genes is dominated by gene conversion. | plasmodium species exhibit the unprecedented situation of distinct, stage-specific rrna sequences. we present an analysis of two pairs of sequences of the small rrna subunit (plasmodium falciparum and plasmodium berghei) and show that these genes do not evolve independently and that in fact their evolution is dominated by gene conversion. this analysis also shows that no extensive stage-specific sequences are conserved in the two species, thus rendering unlikely that the existence of stage-speci ... | 1991 | 1901094 |
| calcium and the malaria parasite: parasite maturation and the loss of red cell deformability. | in the studies reported here, we examined the role of calcium in the maturation of the human malaria parasite plasmodium falciparum, and in the loss of red cell deformability associated with parasite maturation. p. falciparum alters the permeability of its host red cell, which normally maintains submicromolar cytoplasmic concentrations of calcium. infection of the red cell and parasite maturation produce a 30-fold increase in calcium uptake. both parasite maturation and the loss of red cell defo ... | 1991 | 1902127 |
| immune response to soluble exoantigens of plasmodium falciparum may contribute to both pathogenesis and protection in clinical malaria: evidence from a longitudinal, prospective study of semi-immune african children. | some soluble exoantigens of plasmodium have lipopolysaccharide (lps)-like properties and are believed to contribute to the pathogenesis of acute malaria. we have studied cellular and humoral immune responses to several purified exoantigens of plasmodium falciparum in a cohort of children and compared these responses with their subsequent susceptibility to malaria infection and clinical disease. we found no evidence that either lymphoproliferative or interferon-gamma (ifn-gamma) responses to thes ... | 1991 | 1902173 |
| interferon-gamma enhances the effect of antimalarial chemotherapy in murine plasmodium vinckei malaria. | most nonimmune patients with plasmodium falciparum infection are no longer cured by such standard antimalarial drugs as chloroquine. thus, alternative treatment regimens are necessary. a combination therapy was tested consisting of a subcurative dose of chloroquine and interferon-gamma (ifn-gamma) in balb/c mice with lethal plasmodium vinckei malaria. treatment with either agent alone prolonged median survival by 1-2 days compared with placebo-treated mice. however, a combination of 80 microgram ... | 1991 | 1902249 |
| plasmodium falciparum: a comparison of synchronisation methods for in vitro cultures. | | 1991 | 1902796 |
| plasmodium falciparum-infected erythrocytes contain an adenylate cyclase with properties which differ from those of the host enzyme. | it has been postulated that differentiation of the human malaria parasite, plasmodium falciparum, is controlled by camp levels. we have determined that p. falciparum synthesizes an adenylate cyclase with several properties distinct from those of the mammalian host cell enzyme. adenylate cyclase activity was compared in p. falciparum-infected erythrocytes, isolated parasites free of host cell material, and uninfected erythrocyte membranes. the parasite enzyme was unaffected by gtp gamma s, alf4-, ... | 1991 | 1904986 |
| ribosomal rna sequences of sarcocystis muris, theileria annulata and crypthecodinium cohnii reveal evolutionary relationships among apicomplexans, dinoflagellates, and ciliates. | sarcocystis muris is a coccidium with a two-host life cycle involving the domestic cat and the mouse, mus musculus. s. muris and theileria annulata belong to the phylum apicomplexa, but the latter organism is a tick-borne protozoon in the subclass piroplasmea and causes tropical theileriosis in cattle. the small-subunit ribosomal rna (16s-like rrna) coding regions of these organisms as well as that of the free living dinoflagellate crypthecodinium cohnii were amplified using polymerase chain rea ... | 1991 | 1904987 |
| immunogenicity of an engineered internal image antibody. | we engineered an antibody expressing in the third complementarity-determining region of its heavy chain variable region a "foreign" epitope, the repetitive tetrapeptide asn-ala-asn-pro (nanp) of the circumsporozoite protein of plasmodium falciparum parasite, one of the etiologic agents of malaria in humans. a monoclonal antibody to p. falciparum specific for the (nanp)n amino acid sequence bound to the engineered antibody, and a synthetic (nanp)3 peptide blocked this interaction. immunization of ... | 1991 | 1905014 |
| cell cycle-dependent biosynthesis of plasmodium falciparum dna polymerase-alpha. | the dna polymerase-alpha of plasmodium falciparum was characterized according to aphidicolin sensitivity and immunological reactivity with monoclonal anti-sera against human dna polymerase-alpha. two major (105 and 72 kda) and two minor (180 and 130 kda) catalytic subunits of p. falciparum dna polymerase-alpha were detected on activity gels. activity gels did not indicate the presence of a dna polymerase-beta in p. falciparum. metabolically labeled polypeptides at 180, 105, 72, and 52 kda were i ... | 1991 | 1905242 |
| the acute phase response and vitamin a status in malaria. | plasma retinol and 5 carotenes were assayed by high performance liquid chromatography in thai rural and urban malaria patients and matched control subjects. plasma retinol was lower in the rural than in the urban controls and both groups of malaria patients had lower serum retinol concentrations than their respective controls. 29% (6/21) of the rural patients were biochemically deficient in retinol (less than or equal to 0.35 mumol/litre), suggesting severely depleted liver stores of vitamin a. ... | 1991 | 1909468 |
| human cerebral malaria: characterization of malarial antibodies in cerebrospinal fluid. | anti-malarial antibodies were quantified in cerebrospinal fluid (csf) of 17 cases of cerebral malaria, 16 presumptive cases (no demonstrable parasitaemia in peripheral blood but responding to i.v. quinine therapy) of cerebral malaria, and 15 controls. a schizont-enriched plasmodium knowlesi antigen was used in an elisa. anti-malarial antibodies of iga and igm isotypes were not detectable in most of the csf samples analysed, although serum antibody titres were high. however, 88% of csf from cereb ... | 1991 | 1914232 |
| in vitro translation of plasmodium falciparum aldolase is not initiated at an unusual site. | it has been proposed recently that translation of fructose-1,6-diphosphate aldolase of the malaria parasite plasmodium falciparum is initiated at a uag codon, both in the parasite and in a rabbit reticulocyte cell-free translation system. we have introduced mutations around that uag codon and find that cell-free expression of a construct encoding an aug in this position results in a slightly larger translation product. the translation product of the construct encoding the uag codon is of the sam ... | 1991 | 1915282 |
| malaria in pregnancy: clinical features and outcome of treatment. | over two consecutive malaria seasons in 1987 and 1988, 37 patients were admitted to the gonder college hospital with malaria in pregnancy. in 10 patients the diagnosis was missed initially and delayed for up to 72 hours after admission. the differential diagnoses considered on first line included incomplete abortion, labour, postpartum haemorrhage, and fulminant hepatitis in pregnancy. twelve patients (32.4%) died, five of these died undelivered. fifteen pregnancies (40.5%) ended up in abortion, ... | 1991 | 1915317 |
| plasmodium falciparum: the calmodulin gene is not amplified or overexpressed in chloroquine resistant or sensitive isolates. | the in vitro growth of plasmodium falciparum is sensitive to some calmodulin antagonists and these compounds show antagonism with classic antimalarials such as chloroquine suggesting competition for the same drug binding site. in order to ask if calmodulin is involved in resistance to chloroquine we cloned the calmodulin gene of p. falciparum. we show that it is encoded by a single gene and that the putative protein is highly homologous to calmodulin from other eukaryotes. the calmodulin gene is ... | 1991 | 1915742 |
| detection of polymerase chain reaction-amplified malarial dna in infected blood and individual mosquitoes. | chelex treatment of plasmodium falciparum and p. berghei infected tissues, in lieu of organic extraction, was followed directly by polymerase chain reaction amplification of primed circumsporozoite gene sequences. the amplified dna products were detected in stained gels and hybridization blots of extracts from individual infected mosquitoes and dissected mosquito tissues as well as small volumes of infected blood. parasite development, within the mosquito midgut and salivary gland, was also moni ... | 1991 | 1915745 |
| plasmodium falciparum: an invasion inhibitory human monoclonal antibody is directed against a malarial glycolipid antigen. | a plasmodium falciparum malaria blood stage antigen was detected using a human monoclonal antibody (mab a52a6) obtained from a clinically immune donor. immunofluorescence analysis showed that the mab reacted with the intracellular parasite throughout the asexual blood stage cycle as well as with gametocytes. the mab also reacted with the surface of erythrocytes containing late stage p. falciparum parasites. the antigen seen by the mab was species- but not strain- or isolate-specific. at rupture ... | 1991 | 1915746 |
| plasmodium falciparum: the effect of ph and ca2+ concentration on the in vitro cytoadherence of infected erythrocytes to amelanotic melanoma cells. | cytoadherence of plasmodium falciparum-infected erythrocytes to amelanotic melanoma cells was ph dependent; increased adherence was observed in the ph range of 6.1 to 6.8 and was greatest between ph 6.6 and 6.8 ca2+ promoted cytoadherence, but at higher concentrations (40-50 mm) than is usually the case for cell-cell adhesion. the effects of ph and ca2+ were interdependent--the ph optimum of cytoadherence was altered by the ca2+ concentration in the medium. the adherent properties of several p. ... | 1991 | 1915750 |
| antimalarial effect of cyclosporin-a on murine p. berghei and human p. falciparum. | the effects of cyclosporin-a (csa) on the growth of plasmodia were investigated in an experimental murine model in vivo and on human malaria in vitro. mice were inoculated with plasmodium berghei and then treated with different doses of csa at the patent period. the development and course of this normally lethal parasitaemia in mice was affected by treatment with csa which is a known immunosuppressant. the drug showed complete protection at a dose of 20 mg/kg wt/day without any recrudescence. an ... | 1991 | 1915980 |
| symptomatic diagnosis of plasmodium falciparum malaria in field conditions. | this paper examines the relationship between clinical manifestations and parasitaemia in relation to malaria endemicity. discriminant analysis, showed that fever alone can detect 74.4% of the parasite positive cases and the inclusion of other symptoms like headache, vomiting, nausea, bodyache and diarrhoea marginally increases the efficiency of discrimination (i.e., from 74.4% to 74.7%). it was observed that the association of symptoms with parasitaemia varies with the degree of malaria endemici ... | 1991 | 1915984 |
| [clinical experiences with mefloquine in tropical malaria--a prospective study]. | the therapeutic effects and side effects of mefloquine in falciparum malaria were investigated in an open prospective trial involving 20 patients. none of them had a history of neurologic or psychiatric disorders. mefloquine was given in a total dose of 1500 mg base. the cure rate was 100%, fever and parasitemia subsided within 3 days. side effects were vomitus and nausea in 25% of the patients. no neurological or psychiatric disorders were observed. mefloquine was shown to be a safe therapeutic ... | 1991 | 1916870 |
| stage-dependent alteration of negative charges of uninfected erythrocytes in plasmodium falciparum culture. | | 1991 | 1917774 |
| immunization strategies for the production of rat monoclonal anti-idiotope antibodies. | anti-idiotypic antibodies are powerful reagents for the study of immunoregulation, and have potential interest as vaccines against tumors and infectious diseases. three immunization strategies for the production of rat monoclonal anti-idiotope antibodies have been compared in this paper. male wistar rats were immunized i.p. and at multiple subcutaneous sites with 750 micrograms of purified monoclonal antibody against plasmodium falciparum for three times and subsequently boosted by (1) intraperi ... | 1991 | 1919018 |
| enhanced uptake and metabolism of riboflavin in erythrocytes infected with plasmodium falciparum. | riboflavin deficiency inhibits the growth of malaria parasites both in vitro and in vivo in infected animals and humans. although the precise mechanisms underlying this inhibition are unknown, they may involve enhanced requirements for riboflavin by parasites. to investigate this possibility, the rate of uptake of [14c]riboflavin and the biosynthesis of fmn and fad from riboflavin were studied in infected (5-8% parasitemia) and uninfected human erythrocytes. all cells were incubated for 0-3 h at ... | 1991 | 1920146 |
| peptide derivatives specific for a plasmodium falciparum proteinase inhibit the human erythrocyte invasion by merozoites. | a specific proteinase of p. falciparum merozoites has been detected by using hydrosoluble fluorogenic peptidic substrates synthesized by classical peptide chemistry; their n-terminal end was acylated by a gluconoyl group that protects them from aminopeptidase degradation and increases their hydrosolubility, and their carboxylic end was substituted by a 3-amino-9-ethylcarbazole group. the sequence val-leu-gly-lys was found to be the most specific substrate. on this basis, reversible peptidic inhi ... | 1991 | 1920353 |
| antimalarial activity and cytotoxicity of evodia fatraina stem bark extracts. | stem bark extracts of evodia fatraina (rutaceae) were tested for antimalarial activity in vitro on plasmodium falciparum using an isotopic semi-microtest and in vivo on plasmodium berghei in mice. ethyl acetate extract showed moderate antimalarial activity in vitro (ic50 = 8.5 micrograms ml-1). however, ethanolic extract exhibited significant potency in vivo (65% suppression of parasitaemia). moreover, low toxicity against hela cells and l 929 fibroblasts was observed with ethanolic extract (ic5 ... | 1991 | 1921419 |
| reversed siderophores as antimalarial agents. ii. selective scavenging of fe(iii) from parasitized erythrocytes by a fluorescent derivative of desferal. | we introduce here a fluorescent derivative of desferrioxamine b (dfo) that retains the high affinity of the parent compound and displays a powerful inhibition of intraerythrocytic plasmodium falciparum growth. nbd-dfo was synthesized by coupling 7-nitrobenz-2-oxa-1,3-diazole (nbd) to the terminal amino group of dfo. the nbd group at this position renders the dfo molecule more lipophilic and imparts to it fluorescent properties. the novel nbd-dfo probe displays a unique combination of chemical an ... | 1991 | 1921988 |
| amplification of the multidrug resistance gene pfmdr1 in plasmodium falciparum has arisen as multiple independent events. | the multidrug resistance (mdr) phenotype in mammalian tumor cells can involve amplification of mdr genes that results in overexpression of the protein product termed p-glycoprotein. chloroquine resistance (cqr) in plasmodium falciparum has similarities with the mdr phenotype in tumor cells, and some isolates of p. falciparum have amplified levels of the pfmdr1 gene. to investigate the nature and origin of pfmdr1 amplicons, we have cloned large regions of a 110-kb amplicon from the cqr cloned iso ... | 1991 | 1922044 |
| characterization of murine monoclonal antibodies against a repetitive synthetic peptide from the circumsporozoite protein of the human malaria parasite, plasmodium falciparum. | monoclonal antibodies (mabs) were raised in mice against the synthetic peptide (nanp)40, consisting of 40 (nanp) repeats of the circumsporozoite (cs) protein of the human malaria parasite, plasmodium falciparum, and characterized. (i) five of these mabs recognized the p. falciparum cs protein in western blot experiments and in immunofluorescence assays using different preparations of sporozoites. the remaining two mabs (ct3.2 and ct3.3, both igg1) gave negative results by both techniques. (ii) w ... | 1991 | 1922106 |
| long-range restriction maps of size-variable homologous chromosomes in leishmania infantum. | in order to clarify the interpretation of molecular karyotype polymorphisms in leishmania, the three smallest chromosomes from five cloned strains of leishmania infantum were identified by chromosome-specific anonymous dna probes. the presence in the same clone of homologous chromosomes of a different size was demonstrated. the chromosome size polymorphism appeared even more dramatic, with size variations affecting up to 20% of the chromosome, and the two smallest bands in one strain being equiv ... | 1991 | 1922200 |
| minimal variation in pfs16, a novel protein located in the membrane of gametes and sporozoites of plasmodium falciparum. | | 1991 | 1922202 |
| partial sequences of three new asparagine-rich blood stage proteins of plasmodium falciparum. | | 1991 | 1922204 |
| species-specific patterns of dna bending and sequence. | nucleotide sequences in the genembl database were analyzed using strategies designed to reveal species-specific patterns of dna bending and dna sequence. the results uncovered striking species-dependent patterns of bending with more variations among individual organisms than between prokaryotes and eukaryotes. the frequency of bent sites in sequences from different bacteria was related to genomic a + t content and this relationship was confirmed by electrophoretic analysis of genomic dna. howeve ... | 1991 | 1923808 |
| the importance of surface charge in the optimization of antigen-adjuvant interactions. | the adsorptive behavior of the recombinant malarial antigens r32tet32, r32ns181 and ns181v20 to aluminum hydroxide and aluminum phosphate gels was studied as a function of ph and buffer ions. the plasmodium falciparum antigen, r32ns181, and the p. vivax antigen, ns181v20, with isoelectric points (pi) of 5.9 and 5.5, respectively, adsorbed readily to the positively charged boehmite form of aluminum hydroxide gel. these two antigens displayed reversible, linear adsorption behavior in the ph range ... | 1991 | 1924135 |
| effect of the 8-aminoquinoline primaquine on culture-derived gametocytes of the malaria parasite plasmodium falciparum. | gametocytes from the honduras i/cdc clone hb-3 of plasmodium falciparum were exposed to different concentrations of primaquine diphosphate. it could be shown that the drug acts specifically on the mitochondria of the cells by destroying their internal structure and causing these organelles to swell. | 1991 | 1924253 |
| antigenic variation in plasmodium falciparum. | antigenic variation of infectious organisms is a major factor in evasion of the host immune response. however, there has been no definitive demonstration of this phenomenon in the malaria parasite plasmodium falciparum. in this study, cloned parasites were examined serologically and biochemically for the expression of erythrocyte surface antigens. a cloned line of p. falciparum gave rise to progeny that expressed antigenically distinct forms of an erythrocyte surface antigen but were otherwise i ... | 1991 | 1924380 |
| exchange transfusion for malaria: what are the indications? | | 1991 | 1925297 |
| [continuous quinidine infusion and blood exchange transfusion in severe tropical malaria: a case report]. | we report on a serious case of malaria due to plasmodium falciparum. although the 46-year-old swiss female had strictly followed the recommended prophylaxis with proguanil and chloroquine she was infected during a stay in namibia which had lasted several month. the patient had poor prognostic signs such as encephalopathy (cerebral malaria), a parasitemia of 34% but only moderate renal impairment. instead of the classical treatment with quinine, the patient was treated with a constant infusion of ... | 1991 | 1925463 |
| induction of plasmodium falciparum transmission-blocking antibodies by recombinant vaccinia virus. | many candidate antigens of malaria vaccines have limited immunological recognition. one exception is pfs25, a cysteine-rich, 25-kilodalton sexual stage surface protein of plasmodium falciparum. pfs25 is a target of monoclonal antibodies that block transmission of malaria from vertebrate host to mosquito vector. the surface of mammalian cells infected with a recombinant vaccinia virus that expressed pfs25 specifically bound transmission-blocking monoclonal antibodies. furthermore, major histocomp ... | 1991 | 1925544 |
| parasitologic and clinical human response to immunoglobulin administration in falciparum malaria. | the protective effect of african igg antibodies against plasmodium falciparum malaria was investigated by passive transfer in thai patients. sera from 333 african adults were collected in the cote d'ivoire and subjected to extensive screening. one hundred fifty-three samples were discarded for safety reasons, and igg was extracted from those remaining under conditions allowing their use by the intravenous (iv) route. eight thai patients with p. falciparum parasitemia were treated by iv inoculati ... | 1991 | 1928564 |
| failure of falciparum malaria prophylaxis by mefloquine in travelers from west africa. | due to the spread of chloroquine-resistant strains of plasmodium falciparum in french speaking parts of africa, we have found it necessary to prescribe mefloquine for antimalaria prophylaxis to travelers to this area. weekly doses of 125 or 250 mg have been recommended for short journeys. in spite of this regimen, 16 documented cases of falciparum malaria in travelers have been recorded in the bordeaux hospital center since october, 1988. fifteen of these patients were tourists returning from we ... | 1991 | 1928565 |
| [ideal treatment of malaria attack: more questions than answers? experience of a department of infectious diseases]. | the number of cases of malaria imported to western europe from tropical areas is steadily growing, due to the increased number of people traveling to endemic regions and to the spread of plasmodium strains resistant to chemoprophylaxis. this has prompted the who to frequently update its guidelines concerning preventive therapy. we report on 143 consecutive cases of benign attacks of malaria in patients returning primarily from western and central africa. plasmodium falciparum was responsible for ... | 1991 | 1929049 |
| [surveillance of the in-vivo chemosensitivity of plasmodium falciparum to 4-aminoquinoline in the cameroon]. | | 1991 | 1929598 |
| possible mechanism of action of desferrioxamine and 2,2'-bipyridyl on inhibiting the in vitro growth of plasmodium falciparum (fcr 3 strain). | | 1991 | 1930289 |
| loss of cellular immune reactivity during acute plasmodium falciparum malaria. | sixteen patients suffering from acute plasmodium falciparum malaria were studied. all were residents of an area of unstable malaria-transmission in eastern sudan. blood-samples were drawn at diagnosis, and 7 and 30 days later. blood-samples from thirteen donors, drawn outside the malaria transmission season 5 months prior to the attack, were included in the study. lymphoproliferative responsiveness to purified soluble malarial antigens and to the unrelated antigen ppd was lost during the acute p ... | 1991 | 1931134 |
| toward the elucidation of the mechanism of attachment and entry of malaria sporozoites into cells: synthetic polypeptides from the circumsporozoite protein of plasmodium falciparum bind ca2+ and interact with model phospholipid membranes. | through the joint use of cd, fourier transform ir (ftir), and attenuated total reflectance ftir we have found that synthetic polypeptide models of the plasmodium falciparum circumsporozoite (cs) protein repeat domain bind calcium ions in helicogenic environments. ca(2+)-(nanp)n complexes (n greater than or equal to 20) interact vectorially with model phospholipid membranes orienting their polypeptide axes preferentially along those of the lipid acyl chains. it is proposed that the p. falciparum ... | 1991 | 1932559 |
| reduction of the surface-volume ratio: a physical mechanism contributing to the loss of red cell deformability in malaria. | plasmodia and other intraerythrocytic parasites reduce the deformability of the red cells they infect. one mechanism potentially responsible for this reduction in deformability is the decrease in the surface:volume (s/v) ratio of the red cell which occurs with parasite growth. to examine this hypothesis, normal red cells were allowed to phagocytize polylysine-coated latex spheres 1.0 to 2.9 microns in diameter. deformability decreased progressively with spheres of increasing size, consistent wit ... | 1991 | 1932714 |
| [development of a campaign strategy against malaria in a rice-growing region of burundi]. | epidemiological studies undertaken in an area of low altitude in burundi, revealed microgeographic variations of malaria endemicity, naturally unstable in the area. however transmission is relatively high near rice fields. the transmission increases at the end of the rainy season, period of natural decrease of the vector population combined with an increase of their longevity. indoor spraying with short acting insecticides during that period of the year, reduced considerably the transmission and ... | 1991 | 1933066 |
| susceptibility of plasmodium falciparum to different doses of quinine in vivo and to quinine and quinidine in vitro in relation to chloroquine in liberia. | chloroquine-resistant plasmodium falciparum has been spreading rapidly after its emergence in 1988 in yekepa. the in vivo and in vitro susceptibilities to quinine and quinidine, compared to chloroquine, were studied by investigating the number of treatment days required for radical cure and estimating the quinine concentrations concomitantly. the minimal inhibitory concentrations (mic) for schizont maturation in all successful in vitro tests were 5.12 x 10(-6) mol/l for quinine and 1.28 x 10(-6) ... | 1991 | 1934240 |
| in vivo response of multi-resistant plasmodium falciparum infections to mefloquine and its combination with sulfadoxine/pyrimethamine in cambodia. | | 1991 | 1937278 |
| antibodies and dna probes used to analyze variant populations of the indochina-1 strain of plasmodium falciparum. | ten variant populations derived from the indochina-1 strain of plasmodium falciparum were analyzed by using (i) hyperimmune serum raised against some of these populations in squirrel monkeys and (ii) an oligonucleotide probe based on the rep-20 sequence, which had previously been shown to be a useful marker of diversity. although all 10 subpopulations had an identical fingerprint pattern on southern blots probed with the oligonucleotide, thus demonstrating a homogeneous genetic makeup, they all ... | 1991 | 1937756 |
| antimalarial effects of peptide inhibitors of a plasmodium falciparum cysteine proteinase. | we previously identified a plasmodium falciparum trophozoite cysteine proteinase (tcp) and hypothesized that it is required for the degradation of host hemoglobin by intraerythrocytic malaria parasites. to test this hypothesis and to evaluate tcp as a chemotherapeutic target, we examined the antimalarial effects of a panel of peptide fluoromethyl ketone proteinase inhibitors. for each inhibitor, effectiveness at inhibiting the activity of tcp correlated with effectiveness at both blocking hemogl ... | 1991 | 1939639 |
| an in vivo chloroquine sensitivity study in relation to low transmission potential and imported malaria in kerala. | the study highlights the presence of chloroquine resistant plasmodium falciparum strains in kerala state, india for the first time. the emergence of chloroquine resistant p. falciparum in a low transmission area is dependent on the imported cases while build up of resistance is mainly due to persistence of resistant parasites which have more opportunities for transmission. | 1991 | 1940213 |
| changing response of plasmodium falciparum to chloroquine in west bengal during 1980-1988. | a total of 314 cases of plasmodium falciparum malaria studied during 1980-88 in nine times monitoring revealed three riii foci i.e. two in jalpaiguri and one in purulia districts. the studies showed a parasite clearance of 40 per cent and 32 per cent of p. falciparum cases within seventh day in purulia and jalpaiguri districts respectively, with a dosage of 25 mg per kg body weight, spread over three days in divided doses. increase in transmission potential and prolonged drug pressure with singl ... | 1991 | 1940214 |
| influence of adjuvants on the antibody specificity to the plasmodium falciparum major merozoite surface protein, gp195. | the effect of adjuvants on the specificity of immune responses to the plasmodium falciparum gp195 protein was investigated using adjuvant formulations based on synthetic muramyl dipeptide and monophosphoryl lipid a derivatives, in parallel with cfa and alum. although these immunomodulators were as effective as cfa in inducing an antibody response to gp195, there were distinct differences in the recognition of b cell epitopes by these antibody populations. we have also demonstrated that mhc contr ... | 1991 | 1940375 |
| development of immunity against plasmodium falciparum malaria: clinical and parasitologic immunity cannot be separated. | a total of 1622 individuals of all ages living under conditions of continuous malarial transmission in liberia were enrolled in a cross-sectional study of parasite rates, positive parasite densities, and body temperatures. the age-specific plasmodium falciparum-positive parasite densities were greatest at ages 0.5-1.0 year, then slowly declined into adulthood. the age-specific mean body temperature at parasite isodensity showed a steady decline even in the oldest age group. the results do not su ... | 1991 | 1940474 |
| recombinant pfs25 protein of plasmodium falciparum elicits malaria transmission-blocking immunity in experimental animals. | pfs25 is a sexual stage antigen of plasmodium falciparum that is expressed on the surface of zygote and ookinete forms of the parasite. monoclonal antibodies directed against native pfs25 can block completely the development of p. falciparum oocysts in the midgut of the mosquito vector. thus, this 25-kd protein is a potential vaccine candidate for eliciting transmission-blocking immunity in inhabitants of malaria endemic regions. we have synthesized, by secretion from yeast, a polypeptide analog ... | 1991 | 1940798 |
| plasmodium species identification by elisa for sporozoites removed from dried dissection slides. | this study tested the feasibility of identifying salavary gland sporozoites to species by plasmodium falciparum elisa by drying them on slides or in vials. the glands were dissected from anopheles gambiae giles s.l. and an. funestus giles collected in western kenya. in 119 gland infections containing a geometric mean of 1,222 sporozoites, a mean of 72.5% of sporozoites were removed in 60 microliters saline from slides at the time of dissection. each of the 119 samples was divided into three 18 m ... | 1991 | 1941915 |
| a new laboratory technique for malaria diagnosis. | | 1991 | 1942489 |