| susceptibility of owl monkeys to plasmodium falciparum in relation to hemoglobin and karyotype. | humans with inherited abnormalities of hemoglobin (hb) synthesis have less frequent and less severe infections of malaria. this study sought to determine if karyotypic variation in the owl monkey was expressed as differences in hb moieties and if it offered a selective advantage in susceptibility to malaria. five karyotypes of owl monkey were evaluated on the basis of the electrophoretic mobility of their major and minor hb components. the results of 40 owl monkeys of different karyotypes demons ... | 1992 | 1558276 |
| molecular factors responsible for host cell recognition and invasion in plasmodium falciparum. | in plasmodium falciparum, the rhoptries involved in the invasion process are a pair of flask-shaped organelles located at the apical tip of invading stages. they, along with the more numerous micronemes and dense granules, constitute the apical complex in plasmodium and other members of the phylum apicomplexa. several proteins of varying molecular weight have been identified in p. falciparum rhoptries. these include the 225-, 140/130/110-, 80/60/40-, rap-1 80-, ama-1 80-, qf3 80-, and 55-kda pro ... | 1992 | 1560416 |
| parasitology. skirmishes on the border. | | 1992 | 1560820 |
| changing patterns of malaria in south-east scotland: implications for practitioner awareness and prophylactic advice. | the medical records of all 229 patients with malaria admitted to the edinburgh city hospital between 1969 and 1988 were studied retrospectively. a total of 137 were from africa, 44 from the indian subcontinent, 19 from the far east, 18 from new guinea, 5 from the middle east and 3 from south america. the number of yearly admissions rose markedly after 1983, mainly due to an increase in plasmodium falciparum cases. ninety-four cases (15 with severe parasitaemia) mainly from kenya and nigeria were ... | 1992 | 1561183 |
| phagocyte meets "desperado". | | 1992 | 1561422 |
| vacuolar acidification and chloroquine sensitivity in plasmodium falciparum. | the antimalarial chloroquine concentrates in the acid vesicles of plasmodium falciparum partially as a result of its properties as a weak base. chloroquine-resistant parasites accumulate less drug than sensitive parasites. a simple hypothesis is that the intravacuolar ph of resistant strains is higher than that for sensitive strains, as a consequence of a weakened proton pump in the vacuoles of resistant strains, thereby explaining the resistance mechanism. we have attempted to test this hypothe ... | 1992 | 1562274 |
| effect of malaria on phenol conjugation pathways in perfused rat liver. | the effect of malaria infection (mi) on sulphation and glucuronidation of phenol was investigated in single-pass perfused livers from rats infected with the rodent malaria parasite plasmodium berghei. at a hepatic inflow (cin) phenol concentration of 1 microgram/ml in controls, 52% was metabolized to sulphate conjugate and 37% to glucuronide conjugate at steady state. at this cin, mi had no effect on phenol clearance (cl) (control: 9.63 +/- 0.38 vs mi: 9.65 +/- 0.36 ml/min; p greater than 0.05) ... | 1992 | 1562275 |
| modulation of the cellular immune response during plasmodium falciparum infections in sickle cell trait individuals. | plasma and peripheral blood mononuclear cells (pbmc) were obtained from p. falciparum-infected individuals with and without the sickle cell trait at diagnosis and 7 days after treatment. hbaa and hbas patients were compared for levels of plasma soluble il-2 receptors (il-2r) and the in vitro cellular reactivity to affinity-purified soluble p. falciparum antigens (spag), ppd and phytohaemagglutinin (pha). at diagnosis, hbas patients with clinical disease had lower plasma-soluble il-2r levels and ... | 1992 | 1563096 |
| defence mechanisms and immune evasion in the interplay between the humane immune system and plasmodium falciparum. | immunity to p. falciparum malaria is developed as a result of long term exposure to the parasite and depends on immunological memory. the key directors in immune recognition and regulation of the immunological responses are the t-cells. it seems reasonable to propose that immunity is acquired when a critical mass of t-cells, recognizing relevant malaria antigens, has been developed. these t-cells mediate immunity by regulating macrophage and b-cell activity, but they may also act directly as cyt ... | 1992 | 1563295 |
| safety, immunogenicity, and efficacy of a plasmodium falciparum vaccine comprising a circumsporozoite protein repeat region peptide conjugated to pseudomonas aeruginosa toxin a. | twenty-one malaria-naive volunteers were immunized with a vaccine consisting of a 22-kda recombinant peptide (r32lr), derived from the repeat region of plasmodium falciparum circumsporozoite (cs) protein, covalently coupled to detoxified pseudomonas aeruginosa toxin a. nineteen volunteers received a second dose of vaccine at 8 weeks, and eighteen received a third dose at 8 to 12 months. the vaccine was well tolerated, with only one volunteer developing local discomfort and induration at the site ... | 1992 | 1563771 |
| detoxified exoantigens and phosphatidylinositol derivatives inhibit tumor necrosis factor induction by malarial exoantigens. | we have previously shown that malaria parasites liberate exoantigens which, through a phospholipid component, stimulate mouse macrophages to secrete tumor necrosis factor (tnf), which are toxic to d-galactosamine-sensitized mice, and which therefore might be involved in pathology. plasmodium yoelii exoantigens detoxified by dephosphorylation or digestion with lipases do not induce tnf production. however, these partial structures inhibited its production in response to the exoantigens, although ... | 1992 | 1563780 |
| defined medium supporting development of cleansed plasmodium berghei ookinetes in anopheles stephensi. | hamsters blood infected with plasmodium berghei was cultured in vitro for the development of ookinetes. the ookinetes were separated from blood components, suspended in various defined media and fed to anopheles stephensi through a membrane. the development of the oocysts and infective sporozoites was recorded. mosquitoes infected with ookinetes suspended in l15 formulated into l15-b, l15-d (a medium specially modified for this purpose), ipl-41 or 199 media with no proteins added, developed at l ... | 1992 | 1563917 |
| a comparative study of the kinetic changes of hemopoietic stem cells in mice infected with lethal and non-lethal malaria. | the kinetic changes of hemopoietic stem cells in bone marrow and spleen were compared between lethal plasmodium berghei- and non-lethal p. yoelii 17x-infected mice. p. yoelii 17x-infected mice showed more severe splenomegaly than those infected with p. berghei. p. yoelii 17x-infected mice also showed a greater degree of sustained increase in number of multipotent hemopoietic stem cells (colony-forming units in spleen: cfu-s) and committed stem cells for granulocytes and macrophages (cfu-gm) and ... | 1992 | 1563919 |
| embryotoxic and growth-retarding effects of malaria on pregnant mice. | the effect of the malaria parasite, plasmodium berghei berghei, on reproductive physiology was studied in mice. three groups of randomly bred mice consisting of two groups of pregnant females and one group of nonpregnant females were used for the study. blood-induced infections in mice were used. endocrinologic evidence was found of an imbalance in endocrine function in the mice with infections. although there was an elevation in white blood cell counts, the red blood cell counts decreased as th ... | 1992 | 1564714 |
| isolation and characterization of a cysteine proteinase gene of plasmodium falciparum. | we have previously identified a 28-kda cysteine proteinase of plasmodium falciparum trophozoites that appears to be an essential malarial hemoglobinase and a potential target for antimalarial chemotherapy. the trophozoite cysteine proteinase (tcp) shares a number of biochemical properties with the lysosomal cysteine proteinase cathepsin l. to isolate the gene encoding tcp, we synthesized degenerate oligonucleotides based on two amino acid sequences of cathepsin l that are well conserved among pa ... | 1992 | 1565129 |
| localization of the 175-kilodalton erythrocyte binding antigen in micronemes of plasmodium falciparum merozoites. | | 1992 | 1565131 |
| binding of plasmodium falciparum 175-kilodalton erythrocyte binding antigen and invasion of murine erythrocytes requires n-acetylneuraminic acid but not its o-acetylated form. | sialic acid on human erythrocytes is involved in invasion by the human malaria parasite, plasmodium falciparum. mouse erythrocytes were used as a reagent to explore the question of whether erythrocyte sialic acid functions as a nonspecific negative charge or whether the sialic acid is a necessary structural part of the receptor for merozoites. human erythrocytes contain n-acetylneuraminic acid (neu5ac), whereas mouse erythrocytes, which are also invaded by p. falciparum merozoites, contain 9-o-a ... | 1992 | 1565137 |
| dynamics of fever and serum levels of tumor necrosis factor are closely associated during clinical paroxysms in plasmodium vivax malaria. | paroxysms are sharp episodes of high fever accompanied by chills and rigors that occur periodically, once in every 48 hr in plasmodium vivax infections. we have measured the changing levels of serum tumor necrosis factor (tnf) during paroxysms in non-immune patients infected with p. vivax malaria. the changes in tnf levels closely paralleled the rise and fall in temperature during the paroxysms but tended to precede them by 30-60 min. these observations suggest that the rise and fall in temperat ... | 1992 | 1565611 |
| activity of chloroquine and desferrioxamine in vitro against newly isolated plasmodium falciparum and their antagonism in combination. | | 1992 | 1566289 |
| antimalarial activity in vitro of the n-desbutyl derivative of halofantrine. | | 1992 | 1566290 |
| seasonal changes in cell mediated immune responses to soluble plasmodium falciparum antigens in children with haemoglobin aa and haemoglobin as. | in this longitudinal study peripheral blood mononuclear cells (pbmc) were obtained before and during the malaria season from healthy hbaa and hbas children. cells were compared for proliferation in response to stimulation by soluble plasmodium falciparum antigens (spag) or purified derivative of tuberculin (ppd). the lymphoproliferative responses to spag of the paired pbmc samples showed 2 distinct seasonal changes in relation to the haemoglobin phenotype. in hbaa children, the lymphoproliferati ... | 1992 | 1566293 |
| presence of antibody to a heterologous circumsporozoite protein of plasmodium vivax (vk247) in southeastern bangladesh. | | 1992 | 1566294 |
| rapid detection of pfmdr1 mutations in chloroquine-resistant plasmodium falciparum malaria by polymerase chain reaction analysis of blood spots. | | 1992 | 1566295 |
| studies on a new antimalarial compound: pyronaridine. | pyronaridine, a hydroxyanilino-benzonaphthyridine derivative synthesized in 1970, is a new antimalarial compound which has been in use in china for more than 10 years. the drug is highly effective against plasmodium falciparum and p. vivax. furthermore, it is efficacious in combatting chloroquine-resistant strains of falciparum malaria both in vitro and in vivo, in human patients. extensive field studies involving several thousand cases have shown that pyronaridine has promising therapeutic valu ... | 1992 | 1566313 |
| plasmodium chabaudi and trypanosoma cruzi infections can reverse igg2ab chronic suppression in mice. | the effects of infections with plasmodium chabaudi or trypanosoma cruzi on chronic cd8+ t cell dependent igg2ab suppression were analyzed in homozygous ighb/b adult mice. these parasites are known to induce a cd4+ t cell dependent polyclonal activation characterized in particular by a considerable increase in igg2a expression. we report here that infection with either parasite reversed the igg2ab suppression in 18 out of 32 mice. however, in mice treated with anti-cd4 mab in parallel to the para ... | 1992 | 1567793 |
| dietary fish-oil supplementation in experimental gram-negative infection and in cerebral malaria in mice. | dietary fish-oil supplementation interferes with eicosanoid production and appears to decrease production of interleukin-1 (il-1) and tumor necrosis factor (tnf). the effect of fish oil was investigated in an intramuscular klebsiella pneumoniae infection in swiss mice and in cerebral malaria induced by plasmodium berghei in c57b1/6 mice. after a low inoculum of k. pneumoniae, 90% of fish oil-fed mice survived; survival in control mice fed equal amounts of corn or palm oil or normal chow was 30%, ... | 1992 | 1569340 |
| norfloxacin is inferior to chloroquine for falciparum malaria in northwestern zambia: a comparative clinical trial. | fluoroquinolones are active against plasmodium falciparum in vitro. in a prospective, randomized, comparative trial, norfloxacin, 400 mg twice a day for 3 days, was compared with a standard course of chloroquine in semiimmune adults with symptomatic falciparum malaria in northwestern zambia, where chloroquine resistance is uncommon. patients were followed for 28 days. the trial was terminated after 38 patients were studied because chloroquine was markedly more effective, curing all 18 patients ( ... | 1992 | 1569341 |
| mouse model for exoerythrocytic stages of plasmodium falciparum malaria parasite. | research on the exoerythrocytic (ee) stages of human malaria parasites has been hindered because of the lack of an easily available suitable animal model. we report here an approach to produce mature ee-stage plasmodium falciparum parasites by using severe combined immunodeficient (scid) mice with transplanted human hepatocytes. transplantation of human hepatocytes into scid mice (scid hu-hep), their subsequent intravenous infection with p. falciparum sporozoites, and the development of mature l ... | 1992 | 1570289 |
| [the diagnostic and treatment characteristics of tropical malaria]. | | 1992 | 1570700 |
| reduced deformability of thalassemic erythrocytes and erythrocytes with abnormal hemoglobins and relation with susceptibility to plasmodium falciparum invasion. | a number of genetically variant erythrocytes showed decreased deformability of both intact cells and membranes prepared therefrom as measured by laser diffractometry. erythrocytes associated with minor or no clinical symptoms (eg, alpha-thalassemia traits, hemoglobin [hb] e trait, hb constant spring trait), which showed only a minimal decrease in deformability, were, in general, invaded efficiently by the malarial parasite plasmodium falciparum. other variant erythrocytes (beta-thalassemia/hb e, ... | 1992 | 1571557 |
| the role of interleukin-6 in vitamin a deficiency during plasmodium falciparum malaria and possible consequences for vitamin a supplementation. | kinetics of serum levels of interleukin-6 (il-6) were studied in patients with acute plasmodium falciparum malaria in relation to vitamin a and its binding proteins, retinol binding protein (rbp) and pre-albumin. it was found that il-6 levels followed the rise and decrease of parasitaemia by 12 hr and correlated inversely with levels of vitamin a and its binding proteins. these data suggest that vitamin a supplementation alone might still be insufficient to restore a malaria-induced vitamin a de ... | 1992 | 1572702 |
| [malaria and pregnancy. therapeutic problems, a case report]. | malaria is an old but still current parasitosis. transmitted by the bite of the female anopheles, it can be revealed by more or less serious symptoms according to the species of plasmodium. plasmodium falciparum is responsible for the serious forms. it is the most frequent species, resistant to 4 amino-quinolein and sulfamides in some areas. p. vivax and p. ovale, usually harmless, are not so widely geographically spread as p. falciparum; and apparently are not drug resistant but they expose pat ... | 1992 | 1573223 |
| efficacy, safety and acceptability of halofantrine in the treatment of acute plasmodium falciparum malaria in african children (gabon). | halofantrine chlorhydrate 2 per cent suspension was given to 50 children (mean age 6.2 years in a dose of 8 mg/kg three times a day as a single day treatment. the children were born and lived in gabon, where malaria transmission is continuous. they all had acute plasmodium falciparum malaria. the children were kept in hospital for 5 days, and regularly followed over a 15-day period. the 50 children were cured and efficacy was evaluated as good in 44 cases, and excellent in six cases, as judged b ... | 1992 | 1573696 |
| an examination of the mitomycin c induction of chromosome polymorphisms in cultures of plasmodium falciparum. | cloned parasites of the fcr3 strain of plasmodium falciparum that survived treatment with either mitomycin c or ethidium bromide were grown and subcloned. the chromosomes of 10 cloned isolates from each population were analysed by contour-clamped homogenous electric field gel electrophoresis. eight of 10 isolates from the mitomycin c-treated population contained a detectable polymorphic chromosome change while none of the isolates from the ethidium bromide-treated population did. one of the poly ... | 1992 | 1574078 |
| mapping of the region predominantly recognized by antibodies to the plasmodium falciparum merozoite surface antigen msa 1. | the locations of the epitopes of a panel of mouse monoclonal antibodies directed against the plasmodium falciparum merozoite surface antigen msa 1 were mapped by using naturally occurring processed fragments, by chemical cleavage of the protein and by comparison of the isolate-specificity of binding with known sequence variation. by these criteria, the most antigenic region occurs in the cysteine-rich, invariant 19-kda carboxyl terminal domain with 12/19 monoclonal antibodies (mabs) binding to t ... | 1992 | 1574088 |
| the sequence of the p82 rhoptry protein is highly conserved between two plasmodium falciparum isolates. | | 1992 | 1574089 |
| purification and in vitro selection of rosette-positive (r+) and rosette-negative (r-) phenotypes of knob-positive plasmodium falciparum parasites. | we have developed methods for in vitro selection of plasmodium falciparum parasites that bear knob protrusions (k+) and are either of the rosette-positive (k+r+) or rosette-negative (k+r-) phenotypes. cryopreserved parasites from spleen-intact aotus monkeys that were k+, c32 cell adherence-positive (c+), cd36 adherence-positive, and r- with aotus erythrocytes were adapted to continuous growth in human erythrocytes, and selected initially for adherence to c32 melanoma cells. in the absence of ind ... | 1992 | 1575284 |
| a simple method to detect plasmodium falciparum directly from blood samples using the polymerase chain reaction. | we have developed a simple method for treating blood samples permitting direct detection of plasmodium falciparum parasites using the p. falciparum-specific dna probe ppf14 after polymerase chain reaction (pcr) amplification of target dna sequences, and have compared this method with microscopic examination of thick blood smears. for pcr amplification, blood samples were lysed, then filtered onto filter paper. after drying, a piece of the filter paper was added directly to the pcr mixture for am ... | 1992 | 1575288 |
| serologic and genetic characterization of plasmodium vivax from whole blood-impregnated filter paper discs. | the presence in the new world of a variant strain of plasmodium vivax (vk247) containing a unique circumsporozoite (cs) repeat domain was determined by the detection of antibodies to the variant cs protein and by genetic analysis of the cs gene from field isolates. whole blood specimens were collected on filter paper from patients infected with p. vivax in mexico and peru. plasmodium vivax dna was eluted from filter paper samples and the cs gene was amplified by the polymerase chain reaction (pc ... | 1992 | 1575295 |
| effect of cell age on erythrocyte choline transport: implications for the increased choline permeability of malaria-infected erythrocytes. | | 1992 | 1575704 |
| saturable and non-saturable components of choline transport in plasmodium-infected mammalian erythrocytes: possible role of experimental conditions. | | 1992 | 1575705 |
| molecular cloning and serological characterization of a new plasmodium vivax recombinant antigen which contains apolipoprotein b-100 like sequences. | we have isolated a new recombinant antigen 'pv12' of plasmodium vivax by immunological screening of the genomic library. the antigen shows a sequence homology with human apolipoprotein b-100. a large number of p. vivax infected individuals (79%) were seropositive against this antigen. the probable function of this antigen could be to evade the host defence system (i) by inactivating the perforin of natural killer cells and (ii) by engaging the host immune system to produce antibodies against thi ... | 1992 | 1575740 |
| development of plasmodium berghei ookinetes to young oocysts in vitro. | the mosquito stage of plasmodium berghei was cultivated in vitro, with special attention to ookinete transformation into early oocyst. the ookinetes were obtained by in vitro culture of gametocytes taken from infected mice, purified by density gradient of metrizoic acid or a lymphocyte separation medium, and incubated either in acellular culture or in co-cultivations with mosquito cells. in acellular culture, the ookinetes were found to aggregate with each other and transformed from banana to ro ... | 1992 | 1578408 |
| nadp-specific isocitrate dehydrogenase from the simian malaria parasite plasmodium knowlesi: partial purification and characterization. | cell-free schizonts of plasmodium knowlesi, a simian malaria parasite, possess significant isocitrate dehydrogenase (idh) activity, about 90% of which is contributed by the nadp-specific enzyme that is localized in the cytosolic fraction. the enzyme has been partially purified by affinity chromatography using blue sepharose cl-6b. although unstable in nature, it is stabilized by citrate and glycerol. kinetic studies with dl-isocitrate and nadp yielded hyperbolic curves with michaelis constants o ... | 1992 | 1578409 |
| antimalarial activity of new dihydroartemisinin derivatives. 5. sugar analogues. | a series of dihydroartemisinin derivatives containing a sugar moiety was prepared in the search for analogues with good water solubility and high antimalarial activity. the preparation of the new compounds was achieved by treatment of dihydroartemisinin (2) with chlorotrimethylsilane in pyridine solution at -10 degrees c to give a nearly quantitative yield of 10-o-(trimethylsilyl)dihydroartemisinin (3), which was then condensed with 1-hydroxypolyacetylated sugars 5 to give dihydroartemisinin der ... | 1992 | 1578492 |
| cloning and characterization of chromosome breakpoints of plasmodium falciparum: breakage and new telomere formation occurs frequently and randomly in subtelomeric genes. | we analysed the genetic stability of two subtelomeric genes of the human malaria parasite plasmodium falciparum. a pcr based assay, using a telomere and a target-gene specific primer was used to detect potential chromosome rearrangements. we show that chromosome breakage and the formation of new telomeres occur frequently in the two genes coding for histidine rich proteins (hrp i and hrp ii) in laboratory isolates, but remains undetectable in clinical parasite isolates. this finding suggests an ... | 1992 | 1579440 |
| [self-medication of 193 travelers in the tropics. recommendations for clinical counseling of tropical travelers and organization of a tropical travel pharmacy]. | medical advice for the traveller is of increasing importance since in the past decade in industrialized countries there is a steady increase in numbers of travellers and distance travelled. self medication was evaluated in 193 travellers to malaria-endemic areas. diarrhoea, fever and headache were the most frequent symptoms. antidiarrhoeal agents, analgetics/antipyretics, antibiotics and oral contraceptives were the drugs most often used by travellers. one case of mefloquine-resistant and chloro ... | 1992 | 1580072 |
| cerebral malaria from plasmodium falciparum. a clinical report. | | 1992 | 1580207 |
| treatment of severe falciparum malaria during pregnancy with quinidine and exchange transfusion. | malaria during pregnancy may be associated with significant morbidity and mortality in both mother and fetus. treatment of severe chloroquine-resistant malaria during pregnancy may be problematic since quinine and related compounds may have a deleterious effect on the course of labor. this article reports the case of a 21-year-old primigravida liberian woman who presented with high-grade (greater than 12%) parasitemia with plasmodium falciparum. the patient was initially treated with chloroquine ... | 1992 | 1580303 |
| a malaria vaccine strategy based on the induction of cellular immunity. | in this article, michael good offers an alternative to the current emphasis on developing subunit, humoral-response-inducing malaria vaccines. he develops a three-pronged proposal comprising (1) a greater emphasis on cellular immunity, (2) analysis of the role of the spleen in protection, and (3) the development of an attenuated vaccine. | 1992 | 1580994 |
| malaria pigment. | | 1992 | 1582489 |
| positive selection and interallelic recombination at the merozoite surface antigen-1 (msa-1) locus of plasmodium falciparum. | dna sequences of alleles at the merozoite surface antigen-1 (msa-1) gene locus of the malaria parasite plasmodium falciparum show evidence of repeated past recombination events between alleles. these include both (1) nonreciprocal recombination events that have homogenized certain gene regions among alleles and (2) reciprocal recombination events that have combined allelic segments with divergent evolutionary histories, thereby enhancing allelic diversity. in three different gene regions, the ra ... | 1992 | 1584009 |
| the effects of nosema algerae on the development of plasmodium yoelii nigeriensis in anopheles stephensi. | experimental simultaneous infections of anopheles stephensi (diptera: culicidae) with nosema algerae (microsporida: nosematidae) and plasmodium yoelii nigeriensis under standardized laboratory conditions showed partial suppression of the malaria parasite. at 9 days after an infective bloodmeal, the oocysts in the midgut were counted; 12.1%-66.6% of the double-infected mosquitoes exhibited no oocysts, whereas only 4.5%-12% of the control group showed no oocysts. the mean reduction in oocyst numbe ... | 1992 | 1584748 |
| a module of the dnaj heat shock proteins found in malaria parasites. | | 1992 | 1585456 |
| vaccination against malaria. | | 1992 | 1587546 |
| cytoadherence and ultrastructure of plasmodium falciparum-infected erythrocytes from a splenectomized patient. | in malarial infections of primates, the spleen has been shown to modulate parasite antigen expression on the surfaces of infected erythrocytes. the processes affected include cytoadherence, which is central to the pathophysiology of severe falciparum malaria, and the related phenomenon of rosette formation. in this study, the cytoadherence and rosette formation behaviors of plasmodium falciparum-infected erythrocytes from a splenectomized patient were examined during the first erythrocytic cycle ... | 1992 | 1587590 |
| protection of aotus monkeys from malaria infection by immunization with recombinant hybrid proteins. | on the basis of investigations of the malarial blood-stage antigens serp, hrpii, and msai from plasmodium falciparum, we chose two escherichia coli-expressed hybrid proteins containing selected partial sequences of these antigens. antibodies raised against both hybrid proteins in rabbits and aotus monkeys recognize the corresponding p. falciparum polypeptides. in two independent trials with 13 animals, immunization of aotus monkeys with either of the two hybrid proteins administered in a well-to ... | 1992 | 1587607 |
| adjuvant effects of liposomes containing lipid a: enhancement of liposomal antigen presentation and recruitment of macrophages. | liposomes containing lipid a induced potent humoral immune responses in mice against an encapsulated malaria antigen (r32ns1) containing nanp epitopes. the immune response was not enhanced by lipid a alone or by empty liposomes containing lipid a. experiments to investigate the adjuvant mechanisms of liposomes and lipid a revealed that liposome-encapsulated r32ns1 was actively presented by bone marrow-derived macrophages to nanp-specific cloned t cells. the degree of presentation was related to ... | 1992 | 1587611 |
| mitochondrial function in babesia bovis. | a variety of anti-mitochondrial drugs that had previously been found to inhibit the growth of the malarial parasite plasmodium falciparum were tested on babesia bovis in vitro. several of these drugs were found to be non-toxic towards b. bovis. however, those drugs that were found to inhibit babesial growth included compounds (shown in parentheses) that have the following putative mitochondrial targets in the parasite: atp synthetase complex (rhodamine 123, oligomycin, janus green); atp-adp tran ... | 1992 | 1587679 |
| absence of effect of retinol on the in vitro development of plasmodium falciparum. | | 1992 | 1587714 |
| actin kinase: a protein kinase that phosphorylates actin of fragmin-actin complex. | actin of fragmin-actin complex is phosphorylated by an endogenous kinase from plasmodium of physarum polycephalum. the phosphorylation abolishes the nucleation and capping activities of fragmin-actin complex. the kinase has been purified and termed actin kinase [furuhashi, k. & hatano, s. (1990) j. cell biol. 111, 1081-1087]. enzymatic properties of the purified actin kinase were studied in detail. actin kinase exhibited the highest activity under conditions physiological for the plasmodium (30 ... | 1992 | 1587799 |
| developmentally regulated infectivity of malaria sporozoites for mosquito salivary glands and the vertebrate host. | sporozoites are an invasive stage of the malaria parasite in both the mosquito vector and the vertebrate host. we developed an in vivo assay for mosquito salivary gland invasion by preparing plasmodium gallinaceum sporozoites from infected aedes aegypti mosquitoes under physiological conditions and inoculating them into uninfected female ae. aegypti. sporozoites from mature oocysts were isolated from mosquito abdomens 10 or 11 d after an infective blood meal. salivary gland sporozoites were isol ... | 1992 | 1588284 |
| codon usage in pathogenic entamoeba histolytica. | | 1992 | 1588599 |
| a host-parasite catalogue of the haematozoa of the sub-saharan birds. | the prevalence of avian haematozoa in 826 species of birds representing 73 families of sub-saharan birds as recorded in the literature or in the files of the international reference centre for avian haematozoa and the veterinary research institute is presented. the most commonly occurring blood parasites were members of the genus haemoproteus which were represented by 63 species which occurred in 19.1% of the sample. twenty-five species of leucocytozoon were recorded in 8.3% of the birds and rep ... | 1992 | 1589208 |
| population genetics and dynamics of plasmodium falciparum: an ecological view. | molecular characterization of the plasmodium falciparum genome has led to identification of polymorphic loci and the mechanisms generating genetic diversity in this parasite. this information has resulted in the development of molecular methods to type parasite diversity in the field. consequently, we are now in a position to describe the population genetics and dynamics of p. falciparum. the limited number of field studies that have been conducted to date have revealed an extraordinary degree o ... | 1992 | 1589299 |
| rapid transport of the acidic phosphoproteins of plasmodium berghei and p. chabaudi from the intraerythrocytic parasite to the host membrane using a miniaturized fractionation procedure. | a miniaturized procedure for the separation of the host erythrocyte membrane from malarial parasites based on saponin lysis and density-gradient centrifugation with percoll is described. the procedure requires only 20-35 microliters packed infected erythrocytes, is simple to perform, needs no sophisticated equipment, and can be completed in less than 2 h. analysis of the isolated erythrocyte membranes and parasites using marker enzymes and electron microscopy revealed that both the purity and th ... | 1992 | 1589427 |
| in vitro activities of chloroquine in combination with chlorpromazine or prochlorperazine against isolates of plasmodium falciparum. | the combinations of chloroquine plus chlorpromazine and chloroquine plus prochlorperazine were evaluated in vitro for potentiation against isolates of plasmodium falciparum. potentiation was observed against all chloroquine-resistant isolates. there was no potentiation against 8 of 10 chloroquine-susceptible isolates. the results indicated that the phenothiazines can potentiate chloroquine action against resistant parasites found in natural conditions. | 1992 | 1590691 |
| use of radioactive ethanolamine incorporation into phospholipids to assess in vitro antimalarial activity by the semiautomated microdilution technique. | phospholipid biosynthetic activity is intense in the erythrocytic stage of plasmodium falciparum because of the parasite's own enzymatic machinery. the incorporation of various labeled phospholipid precursors in comparison with the incorporation of nucleic acid and protein precursors was tested to evaluate p. falciparum growth in vitro. these precursors, namely, [3h]ethanolamine, [3h]hypoxanthine, [3h]palmitate, [14c]serine, [3h]choline, [3h]inositol, and [3h]isoleucine, were all accurate indica ... | 1992 | 1590699 |
| plasmodium falciparum: the repetitive msa-1 surface protein of the ro-71 isolate is recognized by mouse antibody against the nonrepetitive repeat block of ro-33. | we have expressed in escherichia coli the nonrepetitive repeat zone of the msa-1 surface protein of the ro-33 isolate of plasmodium falciparum. the recombinant protein was used to immunize mice and the resulting ro-33 monospecific serum was used to screen our p. falciparum strain collection in order to recover additional alleles lacking tripeptide repeats in block 2 of msa-1. only 1 (ro-71) out of 30 isolates tested reacted strongly with the serum by indirect immunofluorescence assay. surprising ... | 1992 | 1592091 |
| eimeria tenella: growth and drug sensitivity in tissue culture under reduced oxygen. | for plasmodium falciparum in culture, growth is enhanced as oxygen tension is lowered and drug susceptibility, particularly susceptibility to 70s ribosomal and mitochondrial inhibitors, changes. whether similar effects occur in eimeria tenella was tested as a possible explanation for why certain 70s ribosomal inhibitors, while active in eimeria-infected birds, are virtually inactive in vitro under ambient oxygen conditions. it was reasoned that perhaps these agents would exhibit good in vitro po ... | 1992 | 1592094 |
| plasmodium falciparum: rapid detection of dihydrofolate reductase mutations that confer resistance to cycloguanil and pyrimethamine. | | 1992 | 1592095 |
| relationship between body size of adult anopheles gambiae s.l. and infection with the malaria parasite plasmodium falciparum. | the influence of adult female body size of anopheles gambiae s.l. on development of midgut and salivary gland infections by the parasite plasmodium falciparum was investigated in a field study carried out in tanzania. the proportion of mosquitoes infected during a blood meal was independent of size. however, the number of oocysts harboured by infected mosquitoes increased with size of the mosquito. the proportion of mosquitoes with sporozoites, and thus potentially infective to humans, was highe ... | 1992 | 1594289 |
| membrane proteins involved in the adherence of plasmodium falciparum-infected erythrocytes to the endothelium. | plasmodium falciparum (human malaria) infections are characterized by the attachment of erythrocytes infected with mature stage parasites to endothelial cells lining the post-capillary venules, a phenomenon known as sequestration. in the human body, the microvessels of the heart, lungs, kidneys, small intestine, and liver are the principal sites of sequestration. sequestered cells that clog the brain capillaries may reduce blood flow sufficiently so that there is confusion, lethargy, and unarous ... | 1992 | 1596638 |
| congenital malaria in infants of asymptomatic women. | | 1992 | 1596812 |
| [autochthonous malaria in brittany]. | | 1992 | 1596964 |
| an overview of molecular parasitology in china. | molecular cloning technology has been gradually used in the studies of parasitic diseases in china since 1986. the information briefly reviewed here deals mainly with: (1) the molecular cloning of immunogen genes related to schistosome and plasmodium; (2) a diagnostic dna probe for malaria and toxoplasmosis; and (3) dna probes for inter- and intra-specific differentiation of leishmania, schistosome, entamoeba, etc. | 1992 | 1597082 |
| [spontaneous splenic rupture in acute malaria tropica]. | a 44-year-old man developed bouts of fever (up to 40 degrees c) seven days after returning from a holiday in kenya. malaria prophylaxis with chloroquine had been correctly undertaken. concentrations of lactate dehydrogenase and total bilirubin were raised (493 u/l and 3.55 mg/dl, respectively). blood smear revealed the ring forms of plasmodium falciparum. thereupon the patient was given mefloquine in decreasing doses (750/500/250 mg) at intervals of 8 hours. the following night he had a circulat ... | 1992 | 1597109 |
| the role of the mosquito peritrophic membrane in bloodmeal digestion and infectivity of plasmodium species. | secretion and luminal formation of the peritrophic membrane (pm) were induced in female anopheles stephensi and aedes aegypti by feeding the mosquitoes on a warmed suspension of latex particles in ringer's solution. the pm in a. stephensi was produced from apical secretion vesicles stored in the midgut epithelial cells and secreted into the lumen during feeding. in a. aegypti, the pm was formed de novo. when the latex feeding was followed 24 hr later by a meal of lyophilized pig blood, the 2 mos ... | 1992 | 1597785 |
| development of a polymorphic strain of plasmodium vivax in monkeys. | a strain of plasmodium vivax from thailand with a polymorphic repeat unit of the circumsporozoite protein was established in saimiri sciureus boliviensis and 3 species of aotus monkeys. all 11 attempts to transmit infection via sporozoite inoculation, 4 times to splenectomized s. sciureus boliviensis, 2 times to splenectomized aotus nancymai, and 5 times to intact saimiri monkeys, were successful. anopheles freeborni, anopheles stephensi, anopheles dirus, and anopheles gambiae mosquitoes were in ... | 1992 | 1597793 |
| susceptibility of macaca fascicularis monkeys from mauritius to different species of plasmodium. | macaca fascicularis monkeys from mauritius were shown to be susceptible via sporozoite inoculation to 7 species of plasmodium (p. fragile, p. coatneyi, p. gonderi, p. inui, p. cynomolgi, p. knowlesi, and p. fieldi), indigenous to macaques in southeastern asia. four monkeys were sequentially infected with different species of plasmodium to determine maximum and course of parasitemia. in 2 nonsplenectomized monkeys, p. fragile developed maximum parasite counts of only 134 and 155/microliters. for ... | 1992 | 1597796 |
| phylogeny of plasmodium species: estimation and inference. | | 1992 | 1597812 |
| bisquinolines. 1. n,n-bis(7-chloroquinolin-4-yl)alkanediamines with potential against chloroquine-resistant malaria. | on the basis of observations that several bisquinolines such as piperaquine possess notable activity against chloroquine-resistant malaria, 13 n,n-bis-(7-chloroquinolin-4-yl)alkanediamines were synthesized and screened against plasmodium falciparum in vitro and plasmodium berghei in vivo. twelve of the thirteen bisquinolines had a significantly lower resistance index than did chloroquine; the resistance index was apparently unrelated to either in vitro or in vivo activity. except for two compoun ... | 1992 | 1597862 |
| case-control studies of severe malaria. | the majority of children infected with plasmodium falciparum in areas of stable endemicity do not develop severe, life-threatening disease. it is important to identify risk factors for the minority who do. case-control studies in which children with severe disease are compared with children with non-severe disease and with community controls, avoid some of the ethical and logistical problems inherent in such an undertaking. this paper discusses methodological aspects of case-control studies of s ... | 1992 | 1597871 |
| malaria--an old challenge in a modern age. | the incidence of malaria is increasing worldwide, and has reemerged in some areas where it was previously eradicated. the importance of full compliance with prophylactic medication must be stressed to travellers. although aware of malarial symptoms, most travellers do not consult a doctor as soon as they appear. health education about malaria represent a key area of occupational nurses' role. | 1992 | 1598352 |
| malaria and pregnancy in cameroonian women. effect of pregnancy on plasmodium falciparum parasitemia and the response to chloroquine. | the interaction between malaria and pregnancy was investigated in an epidemiologic study conducted in mfou, a rural community in cameroon. the study consisted of both cross-sectional and longitudinal analyses involving 225 pregnant women and 75 nonpregnant controls. information was obtained by a standardized questionnaire to determine the pattern of antimalarial drug use. the parasitologic response to chloroquine was also determined. a dosage of chloroquine base (25 mg/kg of body weight) was giv ... | 1992 | 1598501 |
| experiments on cryopreservation of plasmodium falciparum. | a comparative study was carried out in order to assess the effectivity of the deep-freezing conditions for p. falciparum cultures: 1. by plunging them into liquid nitrogen, 2. by use of an established freezing program for lymphocytes. after thawing in a waterbath at 37 degrees c, samples were diluted with equal volumes of 3.5% sodium chloride solution or 15% phosphate-buffered saline supplemented glucose solution. other samples were not diluted after thawing, but the medium was replaced twice du ... | 1992 | 1598502 |
| the effects of ascorbate-induced free radicals on plasmodium falciparum. | ascorbic acid has been shown to cause stage-dependent effects on the in vitro development of plasmodium falciparum. while vitamin c marginally enhanced the development of young parasites, it proved highly destructive to the advanced forms. the present study evaluates the mechanisms by which vitamin c affects the parasite. the treatment of parasitized erythrocytes with ascorbate resulted in the conversion of added salicylate to dihydroxybenzoate products, indicating the involvement of hydroxyl ra ... | 1992 | 1598503 |
| the incidence of pulmonary manifestations during plasmodium falciparum malaria in non immune subjects. | the incidence of clinical pulmonary manifestations during clinically mild plasmodium falciparum malaria was studied in 50 patients. in nine patients (18%), respiratory symptoms developed and consisted of cough either productive (in 5) or dry and pleuritic (in 3), wheezing and dyspnea (in 2). physical examination of these patients disclosed minimal decrease of breath sounds with diffuse moist rales over both lung bases. chest x-rays showed small infiltrates and increased vascular markenings in mo ... | 1992 | 1598511 |
| the effect of splenectomy on immunity to plasmodium malariae and p. falciparum in a malaria immune donor. | a 55 year old liberian male was splenectomized after an abdominal trauma. a few days after splenectomy he experienced a pure plasmodium malariae infection with high fever. he was later followed for 12 months with monthly blood films and temperature measurements, and did never show any signs of clinical malaria. the parasite densities observed during the longitudinal follow after splenectomy did not differ from parasite densities in villagers with intact spleens. | 1992 | 1598514 |
| differential sensitivity of the pre-erythrocytic stages of plasmodium cynomolgi b to the prophylactic action of primaquine. | the sensitivity of the developing pre-erythrocytic stages of plasmodium cynomolgi bastianelli to primaquine in single, two or three dose regimens administered at varying times during the incubation period has been investigated. the study reveals that the early pre-erythrocytic stages of the parasite are more susceptible to primaquine than the later stages. regimens of 5.34 mg/kg x 1 dose on day 0 or day + 1; 2.67 mg/kg x 2 doses on days 0 and 1 and 1.78 mg/kg x 3 doses on days -1, 0, + 1 or days ... | 1992 | 1598515 |
| an inexpensive and simple method for screening potential antimalarial drugs. | the visual in vitro test proved to be a very useful tool for screening a series of 54 chemical analogues for their antimalarial activity. the test relies on the formation of dark pigment precipitates after an alkaline solution is added to synchronous cultures of plasmodium falciparum. pigment is produced when a chemical compound is unable to prevent the maturation of rings to schizonts during incubation. however, in the presence of effective concentrations of a compound, maturation is inhibited ... | 1992 | 1598517 |
| segregation analysis detects a major gene controlling blood infection levels in human malaria. | the profound influence that the genetic makeup of the host has on resistance to malaria infection has been established in numerous animal studies. this genetic heterogeneity is one of the main causes of the difficulties in developing an effective malaria vaccine. segregation analysis is the first step in identifying the nature of genetic factors involved in the expression of human complex diseases, as infectious diseases. to assess the role of host genes in human malaria, we performed segregatio ... | 1992 | 1598911 |
| rosette formation in plasmodium falciparum isolates and anti-rosette activity of sera from gambians with cerebral or uncomplicated malaria. | the ability of plasmodium falciparum-infected red blood cells (rbc) to form spontaneous erythrocyte rosettes was studied in 130 fresh isolates from gambian children with cerebral or uncomplicated malaria from august to november 1990. all isolates (24 of 24) from patients with cerebral malaria formed rosettes, but only 61 of 106 isolates from children with uncomplicated malaria formed rosettes. the mean rate of rosette formation in isolates from children with cerebral malaria (28.3%) was signific ... | 1992 | 1599043 |
| ultrastructural analysis of fresh plasmodium falciparum-infected erythrocytes and their cytoadherence to human leukocytes. | sixty fresh plasmodium falciparum isolates obtained from gambian children with mild or cerebral malaria were investigated by transmission electron microscopy for the expression of knob-like protrusions (k+) on the surface of the infected erythrocytes. more than six-hundred infected erythrocytes were analyzed. knob-forming parasites were present in all 60 isolates. although knobless parasites (k-) were found in 25 (42%) of the isolates, only 39 were k-, while 577 were k+. nine of the 39 k- infect ... | 1992 | 1599044 |
| effect of different fractions of heparin on plasmodium falciparum merozoite invasion of red blood cells in vitro. | heparin and various heparin fractions were separated according to differences in molecular weight or affinity for antithrombin iii and used for the inhibition of plasmodium falciparum merozoite invasion of red blood cells in vitro. no variation in sensitivity to heparin was found among the four strains of p. falciparum tested; all required approximately 5 micrograms/ml (0.5 u/ml) of heparin for 50% inhibition of invasion. the most efficient fraction of heparin was the one with low affinity for a ... | 1992 | 1599053 |
| disruption of plasmodium falciparum erythrocyte rosettes by standard heparin and heparin devoid of anticoagulant activity. | we have studied the ability of heparin to disrupt spontaneous rosettes formed between plasmodium falciparum-infected and uninfected red blood cells, which has been proposed to have importance in the pathogenesis of cerebral malaria. substantial variation in this activity was found among six laboratory stains of p. falciparum. rosettes formed by three of these strains were highly sensitive to heparin (50% disruption at 0.5-25 micrograms/ml; 1 microgram/ml corresponds to 0.15 iu/ml). the rosettes ... | 1992 | 1599054 |
| probing behaviour and sporozoite delivery by anopheles stephensi infected with plasmodium berghei. | we observed that plasmodium berghei sporozoite-infected anopheles stephensi was not impaired in its ability to locate blood on a host. when probing rats, infected mosquitoes took as long as non-infected mosquitoes to locate blood. contrary to previous suggestions, infective mosquitoes delivered sporozoites into mineral oil even after extensively probing a vertebrate host. we observed that, in mosquitoes having probed a host, both the mean number of sporozoites ejected over 3 min into oil (35.9 v ... | 1992 | 1600229 |
| malaria vaccines. | | 1992 | 1600390 |
| gene inactivation of pf11-1 of plasmodium falciparum by chromosome breakage and healing: identification of a gametocyte-specific protein with a potential role in gametogenesis. | we report the identification of the product of the plasmodium falciparum pf11-1 gene and demonstrate that it is a gametocyte-specific protein that has a potential role in the rupture of the host erythrocyte and emergence of the gametes (gametogenesis). the pf11-1 gene is a large locus (30 kb) whose sequence predicts a glutamic acid-rich polypeptide. our identification of the pf11-1 gene product as gametocyte specific was greatly facilitated by the isolation of a mutant parasite clone in which gr ... | 1992 | 1600948 |
| incidence of hypoglycaemia in children with severe plasmodium falciparum malaria around rourkela, orissa state. | to determine the incidence of hypoglycaemia in children suffering from severe falciparum malaria, 23 patients from rourkela (orissa), were investigated. plasma glucose and immunoreactive insulin were estimated before and at hourly intervals during quinine infusion. no child had hypoglycaemia at the time of admission. correlation between parasite count and prequinine plasma glucose was not significant. in the period of quinine infusion, 20 patients showed fall in plasma glucose during all the thr ... | 1992 | 1601475 |