| 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 |
| ultrastructure of erythrocytes from aotus trivirgatus and saimiri sciureus monkeys infected by plasmodium vivax. | erythrocytes from aotus and saimiri monkeys parasitized by plasmodium vivax show dramatic changes starting during the early stages of parasite development. invaginations of the erythrocyte membrane, caveolae, are found during all parasite development stages. up to six vesicles can be fused with one caveola, forming a caveola-vesicle complex. as the parasite grows, large accumulations of these vesicles can be seen within the erythrocyte cytoplasm. in addition to these caveolae-vesicle complexes, ... | 1991 | 1891448 |
| 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 |
| antimalarial antibodies of the immunoglobulin g2a isotype modulate parasitemias in mice infected with plasmodium yoelii. | previous studies have demonstrated the importance of antibodies in mediating immunity to malaria, but the relative contribution of the different immunoglobulin isotypes has not been assessed. in this study, hyperimmune plasma was generated against plasmodium yoelii and separated by protein a-sepharose chromatography into fractions containing immunoglobulin g1 (igg1), igg2a, igg2b, or igg3 antibodies and the remaining nonbinding plasma proteins, including igm. following concentration, the antimal ... | 1991 | 1894361 |
| 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 |
| monoterpenic fragment analogues of aplasmomycin as potential antimalarial. | seven analogues of monoterpenic fragment of aplasmomycin were synthesized as targeted antimalarial agents. the potency of the compound 6 was comparable with the sesquiterpene lactone artemisinin and the antibiotic aplasmomycin in vivo against plasmodium berghei yoelli. | 1991 | 1895301 |
| [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 |
| update: self-induced malaria associated with malariotherapy for lyme disease--texas. | in december 1990, the texas department of health (tdh) was contacted by a man who had recently moved from the northeastern united states and who was considering malariotherapy for lyme disease (ld). he described a 2-year history of unsuccessful treatment with multiple antibiotics for arthralgias and palpitations, which had been diagnosed as ld. | 1991 | 1896006 |
| 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 |
| induction of colony-stimulating factors by plasmodium cynomolgi components. | plasmodium cynomolgi total parasite antigens soluble in culture medium (p.c.sa), when injected in monkeys (macaca mulatta) intravenously, induced the synthesis and secretion of serum colony-stimulating factors (csfs). in vitro cultured monkey splenic macrophages and blood monocytes, following incubation with p.c.sa, also elaborated csfs: the splenic macrophages responded more. peak csfs levels, both in vivo and in vitro, were attained after 8 hours of p.c.sa stimulation, and thereafter declined ... | 1991 | 1897383 |
| 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 |
| cd4+ and cd8+ t lymphocytes both contribute to acquired immunity to blood-stage plasmodium chabaudi as. | in the present study, the contribution of cd4+ and cd8+ t lymphocytes to acquired immunity to blood-stage infection with the murine malaria species plasmodium chabaudi as was investigated. c57bl/6 mice, which are genetically resistant to infection with this hemoprotozoan parasite and exhibit a transient course of infection, were treated intraperitoneally with monoclonal antibodies to t-cell epitopes, either anti-thy-1, anti-cd4, or anti-cd8. after intraperitoneal infection with 10(6) parasitized ... | 1991 | 1898902 |
| 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 |
| mosquito-transmitted malaria--california and florida, 1990. | in 1990, two persons--one each in california and florida--were diagnosed with malaria classified as cryptic; their infections may have been acquired in the united states through bites of mosquitoes that became infected after biting parasitemic migrant workers. | 1991 | 1899462 |
| cytokines kill malaria parasites during infection crisis: extracellular complementary factors are essential. | malaria infection crisis, at which the parasitemia drops precipitously and the parasite loses infectivity to the mosquito vector, occurs in many natural malaria systems, and has not been explained. we demonstrate that in a simian malaria parasite (plasmodium cynomolgi in its natural host, the toque monkey), the loss of infectivity during crisis is due to the death of circulating intraerythrocytic gametocytes mediated by crisis serum. these parasite-killing effects in crisis serum are due to the ... | 1991 | 1900073 |
| 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 |
| plasmodium berghei: lactic acidosis and hypoglycaemia in a rodent model of severe malaria; effects of glucose, quinine, and dichloroacetate. | fulminant malaria infections are characterised by hypoglycaemia and potentially lethal lactic acidosis. in young adult wistar rats (n = 26) infected with plasmodium berghei (anka strain), hyperparasitaemia (greater than 50%), anaemia (pcv 19.6 +/- 5.3%; mean +/- sd) hypoglycaemia (1.04 +/- 0.74 mmol/litre), hyperlactataemia (13.2 +/- 2.20 mmol/litre), hyperpyruvicaemia (0.51 +/- 0.12 mmol/litre) and metabolic acidosis (arterial ph 6.96 +/- 0.11) developed after approximately 14 days of infection ... | 1991 | 1901269 |
| avian hematozoa from west-central bolivia. | a total of 641 birds representing 135 species of 25 families from noel kempff mercado national park in west-central bolivia was examined for hematozoa; only 33 (5.1%) harbored blood parasites. microfilariae were the most commonly encountered hematozoans, followed, in numerical sequence, by species of haemoproteus and plasmodium; trypanosoma, atoxoplasma, and hepatozoon were seen infrequently. the survey included 13 new host-parasite records, and 58 species of birds were examined for blood parasi ... | 1991 | 1901358 |
| differential t cell responses to plasmodium chabaudi chabaudi in peripheral blood and spleens of c57bl/6 mice during infection. | the definition of the immune status of a person is often taken as the responses obtained from lymphocytes isolated from peripheral blood. we therefore analyzed in a mouse model of plasmodium chabaudi chabaudi the response of t lymphocytes taken from peripheral blood and compared it with the spleen during and after a primary erythrocytic infection. using limiting dilution conditions, no malaria-specific t cell responses could be measured in the peripheral blood for up to 21 days after infection w ... | 1991 | 1901884 |
| 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 |
| ifn-gamma inhibits development of plasmodium berghei exoerythrocytic stages in hepatocytes by an l-arginine-dependent effector mechanism. | primary cultures of balb/cj hepatocytes treated with 10(3) u/ml rifn-gamma consistently inhibited intracellular plasmodium berghei liver schizont development by 50 to 70%. monomethyl-l-arginine (ngmmla), the competitive inhibitor of l-arginine as substrate for production of nitric oxides by hepatocytes, reversed the activity of ifn-gamma on these malaria-infected cells. reversal of ifn-gamma activity by ngmmla was dose dependent and was maximal at 0.5 mm ngmmla. depletion of l-arginine by additi ... | 1991 | 1903415 |
| purification and characterization of dna polymerases from plasmodium berghei. | dna polymerases from the malaria parasite plasmodium berghei were purified more than 50-fold. several distinct enzymatic activities were isolated that could be distinguished by the use of various specific dna polymerase inhibitors. in particular, subdivision into an aphidicolin-sensitive and an aphidicolin-resistant group was possible. further analysis allowed a better comparison with host dna polymerases and indicated that one aphidicolin-sensitive dna polymerase resembled dna polymerase alpha ... | 1991 | 1903844 |
| rosette formation by plasmodium coatneyi-infected red blood cells. | animal models are needed for the study of cytoadherence in falciparum malaria. red blood cell (rbc) rosette formation is one type of cytoadherence and appears to be associated with knob formation, endothelial cell adhesion and sequestration of plasmodium-infected rbcs. since plasmodium coatneyi-infected rbcs develop knobs and sequester, we hypothesized that they also form rosettes. rbcs from p. coatneyi-infected rhesus monkeys (macaca-mulatta) were collected, allowed to mature overnight in vitro ... | 1991 | 1904195 |
| cd4+t cell-dependent effector mechanisms important in the immune response to the erythrocytic stages of plasmodium chabaudi chabaudi (as). | the ability to produce ifn-gamma during an erythrocytic infection with p. chabaudi chabaudi is not an indicator of resistance or susceptibility of mice to this infection. however, ifn-gamma may play a transient role in immune control of the parasite. we have shown that after its removal in vivo by antibody treatment the acute phase of infection is clearly exacerbated. after the acute phase of infection the t cell response changes from one characterized by ifn-gamma production to one of a t helpe ... | 1991 | 1904712 |
| 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 |
| inhibitory activity against plasmodium vivax sporozoites induced by plasma from saimiri monkeys immunized with circumsporozoite recombinant proteins or irradiated sporozoites. | two saimiri monkey vaccine trials have been conducted comparing four recombinant plasmodium vivax circumsporozoite proteins and irradiated sporozoites. only a small number of animals immunized with certain recombinants or irradiated sporozoites became fully protected against sporozoite challenge. preimmunization and postimmunization plasma samples obtained from 30 monkeys on the day of challenge were tested in an in vitro assay based on sporozoite development into exoerythrocytic stages in prima ... | 1991 | 1907809 |
| 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 |
| gamma interferon production in endotoxin-responder and -nonresponder mice during infection. | the production of gamma interferon (ifn-gamma) in response to infection and to a number of other agents was compared in lpsn (c3h/hen and c57bl/10scsn) and lpsd (c3h/hej and c57bl/10sccr) mouse strains. large differences in ifn-gamma production were observed between c57bl/10sccr mice and the other mouse strains. with the exception of c57bl/10sccr, all mouse strains, including c3h/hej, exhibited transient levels of ifn-gamma during infection with salmonella typhimurium. spleen cells of these mice ... | 1991 | 1910003 |
| 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 yoelii: antibody response in resistant and susceptible mouse strains. | the numbers of antigen-reactive antibody-secreting cells, levels of parasite antigen-specific serum antibodies and numbers of red blood cells staining positive for surface immunoglobulin were determined for susceptible and resistant mouse strains following infection with plasmodium yoelii 17x. as a control, these parameters also were measured using antigen prepared from normal red blood cells. the relatively susceptible c57bl/6 mice produced more antigen-specific antibody-secreting cells and had ... | 1991 | 1915739 |
| 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 |
| effect of plasmodium berghei infection and chloroquine on the hepatic drug metabolizing system of mice. | the hepatic microsomal mixed-function oxidase (mfo) system was markedly impaired during plasmodium berghei infection in mice. cytochrome p-450 and other mono-oxygenases, viz. aniline hydroxylase, aminopyrine-n-demethylase and benzo(a)pyrene hydroxylase, were significantly decreased while microsomal heme showed a four-fold increase at peak parasitemia (greater than 50%). oral treatment with chloroquine (16 mg kg-1 body wt for 4 days) of p. berghei-infected mice cleared the parasitemia within 72 h ... | 1991 | 1917287 |
| 18s rrna sequences of leishmania enriettii promastigote and amastigote. | dideoxy sequencing with reverse transcriptase and universal primers was used to obtain partial sequences of the 18s rrnas from the promastigote and amastigote life-cycle stages of l. enriettii. approximately 1400 nucleotides of sequence from the two stages were compared. unlike plasmodium berghei, in which 18s rrnas from the mosquito stage and the mammalian stage of the life cycle are only 96.5% similar, the amastigote and promastigote rrnas of l. enriettii are identical. in addition, a comparis ... | 1991 | 1917290 |
| 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 |
| plasmodium berghei ookinete densities in three anopheline species. | plasmodium berghei ookinete kinetics and densities were examined in the blood meals of 3 species of anopheles mosquitoes fed simultaneously from a gametocytemic mouse. simple techniques were developed for estimating relative and absolute ookinete densities within individual mosquito blood meals. the kinetics of ookinete formation were similar in all 3 species, with peak ookinete densities occurring from 12 to 24 hr postingestion. ookinete densities consistently were lower in anopheles stephensi ... | 1991 | 1919925 |
| 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 |
| from the centers for disease control. self-induced malaria associated with malariotherapy for lyme disease--texas. | | 1991 | 1920712 |
| 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 |
| analysis of msa-1 diversity in plasmodium chabaudi chabaudi strains. | | 1991 | 1922203 |
| partial sequences of three new asparagine-rich blood stage proteins of plasmodium falciparum. | | 1991 | 1922204 |
| [imported malaria. clinico-epidemiologic and therapeutic observations]. | the authors notice a prevalence of p. falciparum in eight observed cases of imported malaria and confirm the increasing polychemioresistance of plasmodium and its prophylactic and therapeutic problems. | 1991 | 1922890 |
| the prevalence of blood parasites in helmeted guineafowls, numida meleagris, in the kruger national park. | bloodsmears were taken from separate groups of five helmeted guineafowls, numida meleagris, shot at approximately monthly intervals at skukuza and near lower sabie in the kruger national park during the period august 1988 to august 1990. ninety-eight (86%) of 114 guineafowls had single or multiple infections of aegyptianella sp., haemoproteus pratasi, hepatozoon sp., leucocytozoon neavei, plasmodium circumflexum and trypanosoma numidae. the apparent seasonal prevalence of aegyptianella sp., h. p ... | 1991 | 1923376 |
| testosterone and other gonadal factor(s) restrict the efficacy of genes controlling resistance to plasmodium chabaudi malaria. | the effect of circulating concentrations of testosterone (te) on resistance to plasmodium chabaudi malaria was investigated in the h-2 congenic mouse strains c57bl/10, b10.a, b10.a(3r), b10.a(4r), and b10.d2. te-levels were determined by radioimmunoassay and resistance was expressed in terms of percent self-healers after challenge with 10(6) p. chabaudi-infected erythrocytes. our data indicate: (i) females and castrated males reveal very similar interstrain variations of resistance. these do not ... | 1991 | 1923561 |
| genetic studies on a major merozoite surface antigen of the malaria parasite of rodents, plasmodium chabaudi. | diversity in a major merozoite surface antigen (msa-1) of plasmodium chabaudi has been examined using a panel of monoclonal antibodies (moabs). the antigen was found to be different in each of twelve cloned isolates, as shown by its reactivity with the moabs in immunofluorescence tests. in genetic crossing experiments, the diverse forms of this antigen were shown to be determined by allelic variation of a single gene. recombination occurred between the msa-1 gene, a second blood stage antigen an ... | 1991 | 1923562 |
| 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 |
| prevalence of blood protozoan parasites of avian species in nsukka area of anambra state, nigeria. | a total of 165 avian species (110 chickens, 15 turkeys, 12 ducks, 10 each of geese and guinea fowls, and 8 pigeons) were examined for blood protozoan parasites. blood samples were collected from the wing veins and smears with giemsa stain. plasmodium spp. were found in 2 chickens (1.6%) and 7 turkeys (46.6%). 5 turkeys were clinical cases. 3 (37.5%) of the pigeons were positive for haemoproteus spp. no blood parasites were found in geese, ducks, and guinea fowls. the results show that avian mala ... | 1991 | 1930107 |
| 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 |