| 566c80: a potent broad spectrum anti-infective agent with activity against malaria and opportunistic infections in aids patients. | 566c80 is a novel hydroxynaphthoquinone with broad-spectrum anti-parasitic properties. in vitro the compound was more potent against plasmodium falciparum than any of the established anti-malarial drugs. it had good activity against the pathogen in aotus monkeys and was also effective in rodents infected with various drug-resistant strains of p. yoelii and p. berghei. in mice the compound showed significant activity against toxoplasma gondii. evaluation of the metabolic stability of 566c80 to na ... | 1991 | 1822435 |
| importance of clinical diagnosis of malaria in national malaria control programme. | the study conducted at kheda district, gujarat, revealed that judgement of patient on the basis of symptoms and diagnosis of the doctor were correct in 50 and 27% of the suspected malaria cases respectively. in malaria control programme, emphasis on health education and passive case detection is indicated. | 1991 | 1822457 |
| a study of current practices in the treatment of malaria in industrial complexes in india. | | 1991 | 1822459 |
| antimalarial activity of crude extracts from brazilian plants studied in vivo in plasmodium berghei-infected mice and in vitro against plasmodium falciparum in culture. | 1. ninety-five crude extracts obtained with either organic solvents or water from 48 brazilian plants or parts of plants were evaluated experimentally as blood schizontocides. seventy-three extracts were obtained from 33 plants randomly collected using an empirical approach, and 22 from 15 "medicinal" plants. 2. the crude extracts were screened in vivo at up to 1.0 g/kg, po, for 4 days in mice infected with blood forms of plasmodium berghei and parasitemia was determined on the fifth day. 3. six ... | 1991 | 1823001 |
| high-titer antisera production using three adjuvants and peptide conjugates derived from malarial surface antigen msa-2. | we have identified a 51-kda glycosylated myristoylated merozoite surface antigen as the target of a number of monoclonal antibodies that inhibit p. falciparum invasion. this antigen has been shown to exist in a limited number of strain-specific forms, but despite wide variation in the sequences of the internal repeat regions both n- and c-terminal elements of the protein are almost totally conserved. accordingly, we prepared a large number of overlapping peptide constructs and demonstrated that ... | 1991 | 1823184 |
| a simple reflectance microphotometer for dot immunobinding assay (dot-elisa) quantification. | the use of a simple reflectance microphotometer adapted to quantify enzymatic dot immunobinding assays is described. the instrument is versatile and precise by clinical laboratory standards (i.e., 1.1% coefficient of variation for ten consecutive readings of a grey cardboard). the instrument provides a low-cost alternative to commercially available equipment for quantitation of dot-elisa assays. | 1991 | 1823264 |
| synthetic peptides in malaria research. | peptides synthesized by solid-phase procedures find a number of applications in research aimed at developing new methods of controlling malaria. the use of peptides has allowed the delineation of b and t cell epitopes in parasite antigens, convenient measurement of antibody levels, analysis of cellular immune responses, cell invasion studies and development of synthetic vaccines. current trends in the use of synthetic peptides in malaria research are outlined in this review. | 1991 | 1823600 |
| resistant falciparum malaria in an endemic area of allahabad (u.p.). | over the last three decades the problems of resistance in p. falciparum malaria to chloroquine have emerged in many parts of the world including india. the present study was carried out at phc, jasra, an endemic area for malaria in allahabad distt. to ascertain the level of resistance to chloroquine in p. falciparum in selected villages according to who extended 28-day field test. one hundred one (58.4%) cases were positive for malaria. amongst the positive cases, 92 (91.1%) showed p. falciparum ... | 1991 | 1824356 |
| plasmodium falciparum: in vitro drug interaction between chloroquine and enantiomers of amlodipine. | both enantiomers of amlodipine, whose calcium antagonist action resides almost exclusively in the r(-) enantiomer, reversed chloroquine resistance in plasmodium falciparum in vitro. r(-) enantiomer was slightly more effective than the s(+) enantiomer in potentiating chloroquine action against chloroquine-resistant strains of parasites. no potentiating effect was observed in chloroquine-sensitive parasites. both enantiomers entered rapidly into parasitized erythrocytes to the same extent. reversa ... | 1991 | 1826656 |
| kinetic modelling of chloroquine uptake by malaria-infected erythrocytes. assessment of the factors that may determine drug resistance. | the antimalarial chloroquine, by virtue of its weak base properties, concentrates in the acidic compartment(s) of the intraerythrocytic parasite. drug accumulation is essential for it to exert its pharmacological activity. drug resistance has been thought to result from insufficient acidification of drug-accumulating organelle(s), (due to weakened proton pump activity and/or proton leak) or to result from the action of the recently suggested active efflux drug pump. in this work we have devised ... | 1991 | 1826839 |
| [changes in tumor necrosis factor in a severe attack of cerebral malaria treated by exsanguination perfusion]. | | 1991 | 1829209 |
| [the importation of malaria into rostov-on-don (1981-1989)]. | the distribution of the imported [correction of exported] cases of malaria has been studied in rostov-on-don for all species of parasites and categories of patients to assess them as effective sources of infection or in other words to determine the degree of jeopardy of the epidemic process recurrence. local cases of malaria and measures directed at their elimination are described. | 1991 | 1829785 |
| in vivo decreased expression of cd25 (p55 chain of il-2 receptor) on cd3+ t cells correlates with low in vitro responsiveness to plasmodium falciparum antigen in subjects living in a malaria endemic area. | significant proliferative responses of peripheral blood mononuclear cells (pbmc) to crude plasmodium falciparum schizont antigen (m.ag) or purified recombinant 31.1 ag (part of gp 195) were observed only in 46 and 39%, respectively, of 50 healthy subjects 5 to 63 years old living in gabon, a malaria-endemic area. high responses to pokeweed mitogen were observed in all the subjects except one. interferon-gamma (ifn-gamma) production paralleled the proliferative response, but in some subjects prol ... | 1991 | 1829993 |
| [prevention and treatment of malaria in expatriates living in black africa. influence of chemoresistance. investigations conducted in brazzaville (congo)]. | the therapeutic, preventive and curative, habits concerning malaria of expatriates living in brazzaville, congo, were investigated on two occasions. in march 1989 and april 1990, a questionnaire was handed out to the pupils of the french school to be filled in by their parents. three quarters of the expatriates are europeans, and 85 percent of these are french. in this country where the chemoresistance of plasmodium falciparum has been established since 1985, chemoprophylaxis was regularly perfo ... | 1991 | 1830144 |
| cytotoxicity of human natural killer (nk) cell subsets for plasmodium falciparum erythrocytic schizonts: stimulation by cytokines and inhibition by neomycin. | quantification of human peripheral blood nk subsets has been made in a group of kenyan adults and children with acute p. falciparum malaria. results were compared with data obtained from three age- and sex-matched control cohorts: parasitaemic but asymptomatic children; aparasitaemic children and adults; and adult caucasians with no previous history of malaria. separated nk subsets were tested in vitro for cytotoxicity to erythrocytic schizonts of p. falciparum in the presence and absence of cyt ... | 1991 | 1833100 |
| plasmodium falciparum merozoites primarily stimulate the v gamma 9 subset of human gamma/delta t cells. | peripheral blood-derived t cells from six unprimed caucasian donors were tested for the in vitro reactivity to plasmodium falciparum merozoites (pfm). without exception vigorous proliferative responses were observed within the donors tested. the frequency of pfm-reactive t cells ranged from 1/150-1/300. phenotypic analysis of peripheral blood lymphocytes cultured in the presence of pfm revealed the preferential outgrowth of gamma/delta t cells, which represented within 7 days about 70% of the re ... | 1991 | 1833205 |
| in vitro and in vivo potentiation of chloroquine against malaria parasites by an enantiomer of amlodipine. | a combination of chloroquine and amlodipine, a derivative of 1,4-dihydropyridine calcium channel blocker, was tested against plasmodium falciparum in vitro and p. yoelii in mice. the dextrorotary enantiomer of amlodipine, practically devoid of calcium channel blocking action, increased chloroquine accumulation inside the infected mouse erythrocytes and potentiated chloroquine action against the resistant strains of p. falciparum in vitro and p. yoelii in mice. unlike the racemate, the dextrorota ... | 1991 | 1834011 |
| [a case of transfusional plasmodium falciparum malaria]. | | 1991 | 1835063 |
| phase i clinical trial of a recombinant malaria vaccine consisting of the circumsporozoite repeat region of plasmodium falciparum coupled to hepatitis b surface antigen. | r16hbsag is an experimental recombinant malaria vaccine consisting of 16 repeats of a four amino acid sequence (asn-ala-asn-pro or nanp) of the circumsporozoite (cs) protein of plasmodium falciparum expressed as a fusion protein with the recombinant hepatitis b virus surface antigen (hbsag) produced by yeast cells. twenty male volunteers were experimentally vaccinated with the product, as well as with two doses of the commercial recombinant hbsag vaccine engerix b (smith kline beecham biological ... | 1991 | 1835311 |
| malaria during pregnancy in an area of unstable endemicity. | a prospective study of malaria during pregnancy was conducted between september 1986 and december 1989 in an area of unstable (mesoendemic) malaria transmission on the thai-burmese border. antenatal clinics were set up in camps for displaced persons of the karen ethnic minority and 1358 pregnant women were enrolled at a mean estimated gestational age of 23 weeks (standard deviation 5.7 weeks) and were followed weekly until delivery. malaria developed in 505 women (37.2%); 80.2% of infections wer ... | 1991 | 1836685 |
| a retrospective study on malaria cases admitted to the university hospital, kuala lumpur, 1984-1988. | a review of malaria cases over a five year period from 1984-1988 at the university hospital, kuala lumpur, malaysia is presented. a total of 64 cases were recorded; 50% of which were due to plasmodium falciparum, 40.6% were due to plasmodium vivax, 6.2% due to plasmodium malariae and 3.1% due to a mixed infection of plasmodium falciparum and plasmodium vivax. the breakdown of species type compared similarly with other studies conducted in the region. of this total, sixteen cases were imported fr ... | 1991 | 1839423 |
| [the results of serological studies in different foci of tropical and tertiary malaria]. | attempt was made to determine the value of serologic indices of malaria surveys. following uniformed methodological and technical approaches 3 foci of p. vivax and 6 foci of p. falciparum malaria were surveyed in different endemic zones of vietnam and the ussr. it was shown that the most objective criteria for a foci classification is its serologic mean geometric titre. the latter in its turn directly depends of transmission longevity in a foci. | 1991 | 1840153 |
| the c-terminal domain of rna polymerase ii of the malaria parasite plasmodium berghei. | the c-terminal domain (ctd) of rna polymerase ii (rnap) has an essential function in the regulation of transcription. the ctd of the human malaria parasite, plasmodium falciparum, differs dramatically from that of higher eukaryotes. to determine whether this is a general feature of malarial parasites, we have analysed the ctd of the distantly related rodent malaria parasite p.berghei. the ctds of the two parasites enzymes are very similar in amino acid composition and contain the basic structure ... | 1991 | 1840489 |
| a new blood stage antigen of plasmodium falciparum highly homologous to the serine-stretch protein serp. | we have isolated the gene coding for a new protein (serp h), highly homologous to the 113-kda serine-stretch protein serp which confers protective immunity to monkeys. the gene consists of four exons interrupted by three short introns located at positions corresponding to those of the serp gene. both genes were shown to be linked on chromosome 2 of plasmodium falciparum suggesting that both originate from a common ancestral gene. both genes are transcribed in the blood-stage form as 3.8-kb mrnas ... | 1991 | 1840623 |
| structure of plasmodium falciparum liver stage antigen-1. | | 1991 | 1840628 |
| the human immune response against the major merozoite surface antigen of plasmodium falciparum. | the major surface antigen of the merozoite (mmsa) is very immunogenic in humans and it is considered a candidate for developing a malaria vaccine. this protein consists of conserved, dimorphic and polymorphic sequences that might differ in their ability to induce immunity. epidemiological studies were undertaken in two different endemic areas of west africa with the aim to identify the sequences within the protein that are the target of the humoral and cellular immune responses. recombinant poly ... | 1991 | 1841197 |
| waiting for the vaccine: sporozoite vaccine research entails important progress in malaria epidemiology. | the research efforts aimed at developing a vaccine against malaria, although failing thus far in their main objective, have produced molecular tools of great utility for epidemiological studies. for example, monoclonal antibodies directed against the repeats of plasmodium circumsporozoite (cs) protein allowed the 2-site assay for detecting sporozoites in mosquitoes to be established. this immunoassay is advantageous compared with the conventional method of salivary gland dissection and microscop ... | 1991 | 1841198 |
| dna diagnosis of falciparum malaria. | we have developed dna diagnosis using universal probe system for the rapid detection of plasmodium falciparum parasite in blood. we chose the dhfr-ts (dihydrofolate reductase-thymidylate synthase) gene as target for detection which are the junction part (410 bp) of and the dhfr part (790 bp). in the parasite, there is only one copy of target sequence, therefore, the target sequences were amplified by pcr (polymerase chain reaction) to increase the sensitivity. our hybridization method consists o ... | 1991 | 1842063 |
| [severe malaria in black africa]. | severe and complicated malaria is a fatal from a human plasmodium falciparum infection. in clinical practice cerebral malaria in children, with unrousable coma, hyperthermia, generalized convulsions, frequently hypoglycemia, is different of severe in non immunized adults resulting in multiple organ failure with degree of impaired consciousness less important. specific treatment requires quinine with loading dose: 16.7 mg/kg then 8.3 mg/kg every 8 hours for 7 days. symptomatic therapy, artificial ... | 1991 | 1842775 |
| [malaria in dakar: epidemiological clinical and parasitological aspects]. | a retrospective case control study is underdone in infections diseases service of dakar (senegal) from june 1 st, 1989 to december 31 st, 1989. 203 observations are collected on the basis of positive blood stream and blood films with plasmodium falciparum. the authors give the epidemiological picture of the two clinical features which are: malignant tertian (107 cases-53%) and intermittent access (96 cases-47%). lethal risk is 12 fold higher in malignant tertian form than in the intermittent one ... | 1991 | 1842776 |
| [in vitro t cell response to merozoite antigens in the area of continuous malaria transmission]. | t cell response in vitro to merozoite extracts of p falciparum was tested in holoendémic area (dielmo, region of fatick). 58 individuals (29 adults and 29 children) were sampled. mononuclear cells from peripheral blood were cultured with the presence of merozoites antigens during 7 days. cells were pulsed at day 6 and 3h-thymidine incorporation was measured 16h later. t cell response high or low was evaluated by stimulation index (si). this is defined as mean cpm expérimental cells/mean cpm cont ... | 1991 | 1842779 |
| [cytoadherence of plasmodium falciparum and complications of malaria]. | sequestration is a phenomenon where mature plasmodium falciparum infected-erythrocytes block microvessels. many cells (particularly epithelial cells) can cytoadhere to these erythrocytes and this may play an important role in the physiopathology of cerebral malaria. many in vitro models have been proposed. they permitted different studies about cytoadherence and clinical effects. contradictory results have been yet published. investigations at a molecular level of cytoadherence moiety contribute ... | 1991 | 1842780 |
| efficacy of a low dose oral quinine therapy in plasmodium falciparum cases of assam, meghalaya and arunachal pradesh in india. | a low dose oral quinine schedule with 1050 mg in two divided doses daily for five days was tried for treatment of plasmodium falciparum cases in assam, meghalaya and arunachal pradesh, in areas where resistance to chloroquine was confirmed. the drug schedule was found effective in 76.92 per cent cases. the treatment was also found effective in 45.55 per cent of the known chloroquine resistant p. falciparum cases. the drug in this low dose was well tolerated and clinical response was quick. | 1991 | 1842806 |
| [malaria induced in the state of sao paulo, brazil]. | a review is presented of 58 induced malaria cases diagnosed in the são paulo state, from january 1983 to july 1990. these cases represent 0.3% of the malaria notifications. the parameters sex, age, parasitaemia, clinical symptoms, clinical course and mean time interval between disease onset and diagnosis were studied in 25 blood-transmitted cases and 28 related to sharing needles. plasmodium vivax was diagnosed in 79.4% and in 5.6% plasmodium vivax and plasmodium falciparum were seen. lower mean ... | 1991 | 1842842 |
| plasmodium falciparum malaria transmission indices in a highland village of the ikopa river valley near antananarivo, madagascar. | data are reported from a malaria survey carried out in june 1991 in the small village of ankadimbazinba, near miantso, about 45 km north-west of antananarivo (madagascar). the objective was to evaluate the level of transmission of p. falciparum by entomological, parasitological and serological indices. all indices were found consistent with the description of a focus of hyperendemic transmission dependent on the presence of an. funestus at high density, corresponding to more than 50 females per ... | 1991 | 1844515 |
| drug susceptibility of plasmodium falciparum in the western amazon region, state of acre, brazil. | field studies in the western amazon region (state of acre, brazil) indicate that the 4-aminoquinolines, as well as the combined regimen with sulfadoxine-pyrimethamine, can no longer be recommended for the treatment and prophylaxis of p. falciparum infections in this region. quinine remains an effective drug when used correctly. however, compliance problems arise due to the often occurring side-effects during a ten day regimen. prospects of overcoming these constraints by combining a short course ... | 1991 | 1844536 |
| treatment of severe plasmodium falciparum malaria with quinidine gluconate: discontinuation of parenteral quinine from cdc drug service. | cdc has recently reviewed data on the reported incidence in the united states of plasmodium falciparum malaria and has evaluated information on the effective management of severe life-threatening infections. as a result of this review, cdc has concluded that the drug of choice in the united states for treatment of complicated p. falciparum infections is parenteral quinidine gluconate. therefore, effective immediately, parenteral quinine dihydrochloride will no longer be available from the cdc dr ... | 1991 | 1848916 |
| treatment with quinidine gluconate of persons with severe plasmodium falciparum infection: discontinuation of parenteral quinine from cdc drug service. | cdc has recently reviewed data on the reported incidence in the united states of plasmodium falciparum malaria and has evaluated available information on the effective management of severe life-threatening infections. as a result of this review, cdc has concluded that the therapeutic drug of choice in the united states for persons with complicated p. falciparum infection is parenteral quinidine gluconate, and that stocking of parenteral quinine dihydrochloride for emergency distribution is no lo ... | 1991 | 1850497 |
| plasmodium falciparum: evidence for a dna methylation pattern. | the methylation status of the adenine and cytosine residues in the genome of plasmodium falciparum was studied using restriction enzymes exhibiting differential activity dependent on the methylation state of these residues in their recognition site. the gene coding for the enzyme dihydrofolate reductase-thymidylate synthase was studied for that purpose. no methylated adenine residues were observed in this gene in four strains tested. however, partial methylation of cytosine residues was observed ... | 1991 | 1851101 |
| localization and stage specific phosphorylation of plasmodium falciparum phosphoproteins during the intraerythrocytic cycle. | fifty-nine plasmodium falciparum specific phosphoproteins with molecular weights between 15,000 and 192,000 were analyzed by sds-page and two-dimensional gel electrophoresis. 40 phosphoproteins were identified by [gamma-32p]atp labeling of cell lysates, 19 by [32p]orthophosphate labeling of parasitic cultures in vivo. changes in the phosphorylation pattern during the infectious erythrocytic cycle were determined for all proteins. in parallel, cell fractionation studies were done to follow up pos ... | 1991 | 1852167 |
| the ring-infected erythrocyte surface antigen of plasmodium falciparum associates with spectrin in the erythrocyte membrane. | the malaria parasite plasmodium falciparum synthesises a protein, resa, which associates with the membrane of newly invaded erythrocytes. using spent supernatants from p. falciparum growing in culture as a source of soluble resa we have developed an assay to examine the characteristics of resa binding to the erythrocyte membrane in vitro. resa associated with the triton x-100 insoluble proteins on the inner face of the host erythrocyte membrane but did not bind to the outer surface of intact ery ... | 1991 | 1852169 |
| an exported protein of plasmodium falciparum is synthesized as an integral membrane protein. | exp-1 is an antigen of plasmodium falciparum which is transported from the parasite cell to the membrane of the parasitophorous vacuole and to membranous compartments in the erythrocyte. to investigate how this protein is transported, we studied the synthesis and membrane translocation of exp-1 in a cell-free system. the protein was translocated into canine pancreatic microsomes. its n-terminal half was thus protected from proteinase k digestion, suggesting that exp-1 is an integral membrane pro ... | 1991 | 1852170 |
| direct sequencing of enzymatically amplified dna of alleles of the merozoite surface antigen msa-1 gene from the malaria parasite plasmodium falciparum. | | 1991 | 1852173 |
| the structure of the calmodulin gene of plasmodium falciparum. | the calmodulin gene and its flanking sequences from the malaria parasite, plasmodium falciparum, have been analysed. the structure of this gene is unique amongst other known calmodulin genes. it exists as a single copy on chromosome 14 and has a single intron. the nucleotide sequence of this 4-kb region suggests the existence of three transcriptional units, each separated by a highly a+t-rich sequence. sequences controlling gene expression might be expected to occur in these intergenic regions. ... | 1991 | 1852174 |
| a stage specific gene expressed at the onset of gametocytogenesis in plasmodium falciparum. | the gene encoding the gametocyte specific cytoplasmic protein pfg27/25 of the human malaria parasite plasmodium falciparum has been cloned. the gene encodes a highly hydrophilic non-repetitive protein which does not share obvious homologies with other polypeptides. the stage specificity of pfg27/25 is controlled at the stage of the production of stable mrna, which is detectable only in the sexual stages of the parasite, and contains long additional sequences outside the pfg27/25 coding region. a ... | 1991 | 1852178 |
| cerebral malaria in children. comparative study between heparin, dexamethasone and placebo. | from january 1987 up to april 1990, sixty two patients diagnosed as cerebral malaria were admitted to the department of child health, medical school sam ratulangi university, gunung wenang general hospital were included in this study. they were treated with quinine dihydrochloride intravenously continued orally for a total of 7 days combined with fansidar by nasogastric tube for 2 days. all patients were also receiving intravenous fluid drips and other symptomatic treatment. they were divided in ... | 1991 | 1852471 |
| longitudinal study of seroreactivities to pf155/resa and its repetitive sequences in small children from a holoendemic area of liberia. | the seroreactivities to pf155/resa antigen and to three oligopeptides (eenv)2, eenvehda and k(ddehveeptva)2, which constitute repeat subunits of the resa molecule, were investigated between 1980 and 1986 in two cohorts of children (n = 114) with and without monthly chemosuppression (pulsed reduction of parasite load) against malaria from six months to five years of age during development of protective immunity. serum samples were collected first at half-yearly and then yearly intervals. positive ... | 1991 | 1852476 |
| human malaria infectiousness measured by age-specific sporozoite rates in anopheles gambiae in tanzania. | in an area of holoendemic malaria in northern tanzania, anopheles gambiae s.l. females were age-graded by polovodova's method and dissected for sporozoites. age-specific sporozoite rates implied that mosquitoes acquired new infections at all ages. the extrinsic period lasted just over 3 gonotrophic cycles (9-11 days). very high sporozoite rates in the oldest females implied the absence or rarity of genetic refractoriness to infection. a method is described for estimating the proportion of bloodm ... | 1991 | 1852484 |
| alterations in erythrocyte membrane phospholipid organization due to the intracellular growth of the human malaria parasite, plasmodium falciparum. | the asymmetric distribution of phospholipids in the erythrocyte membrane during the intracellular development of the human malaria parasite plasmodium falciparum was studied. infected cells of high parasitaemia were treated with phospholipase a2 or sphingomyelinase c, followed by isolation of the host red cell membrane using the affigel (731) bead method. additionally, phosphatidylserine on the surface of infected cells was probed using a phosphatidylserine-sensitive prothrombinase assay. tropho ... | 1991 | 1852485 |
| [the prophylaxis of malaria]. | | 1991 | 1853050 |
| possible congenital hemolytic anemia in prehistoric coastal inhabitants of israel. | the spread of thalassemia among prehistoric populations of the mediterranean basin has been linked to the increased risk to early agriculturalists posed by the plasmodium falciparum parasite. the diagnosis of the disease in human skeletal remains, however, has usually been based on a single pathological criterion, porotic hyperostosis. this paper reports on what we believe to be the earliest case of thalassemia yet identified in the prehistoric record. our diagnosis of the disease in an individu ... | 1991 | 1853944 |
| phagocytosis of liposomes by macrophages: intracellular fate of liposomal malaria antigen. | liposomes containing a synthetic recombinant protein were phagocytosed by macrophages, and the internalized protein was recycled to the cell surfaces where it was detected by enzyme-linked immunosorbent assay. the transit time of the liposome-encapsulated protein from initial phagocytosis of liposomes to appearance of protein on the surfaces of macrophages was determined by pulse-chase experiments. the macrophages were pulsed with liposomes containing protein and chased with empty liposomes, and ... | 1991 | 1854787 |
| stabilization of drug resistance (chloroquine and amodiaquine) of plasmodium falciparum in semiimmune populations in the congo. | | 1991 | 1856500 |
| inhibition of the growth of plasmodium falciparum and plasmodium berghei by the dna polymerase inhibitor hpmpa. | the acyclic adenosine analogue (s)-9-(3-hydroxy-2-phosphonylmethoxypropyl)adenine [hpmpa] belongs to a class of nucleoside analogues originally described as having potent activity against a broad spectrum of dna viruses. we examined the effects of this class of drugs on the growth of cultured plasmodium falciparum. strong inhibition was observed by hpmpa (id50 = 47 nm) at concentrations more than 1000-fold less than the cytotoxic dose for human cells. 3-deaza-hpmpa was even more strongly inhibit ... | 1991 | 1857384 |
| isolation and characterization of rhoptries of plasmodium falciparum. | rhoptries have been isolated from plasmodium falciparum schizont-infected erythrocytes by isopycnic density centrifugation. gradient fractions were analyzed by immunoblotting with antibodies against two polypeptides of 140 and 110 kda, known to be components of the rhoptry. the proteins were present primarily in fractions with a density of 1.16 g ml-1. electron microscopy of these fractions indicated they were enriched in rhoptries. for the most part, the isolated organelle retained in situ morp ... | 1991 | 1857385 |
| preliminary report on the use of desferrioxamine in the treatment of plasmodium falciparum malaria. | the administration of 0.5 g (im) of desferrioxamine every 12 hr for 3 days with 25 mg/kg (total dose for three days) of chloroquine abated the parasitemia of plasmodium falciparum infected individuals more rapidly than chloroquine alone. two patients with in vitro evidence of total or partial resistance to chloroquine also were successfully treated with the combination of drugs, and were free of parasitized red cells by day 7. further clinical trials and development of desferrioxamine in the tre ... | 1991 | 1858775 |
| malaria in travelers in rhode island: a review of 26 cases. | we reviewed our experience with malaria in two community hospitals in rhode island from 1986 to 1990. | 1991 | 1858826 |
| activation of the host response in human plasmodium falciparum malaria: relation of parasitemia to tumor necrosis factor/cachectin, thrombin-antithrombin iii, and protein c levels. | hemostatic alterations and elevated tumor necrosis factor/cachectin (tnf alpha) serum levels may contribute to the pathogenesis of organ complications in human plasmodium falciparum malaria. therefore, we examined whether altered protein c (pc) and thrombin-antithrombin iii (tat) plasma levels correlated with tnf alpha serum concentrations, parasitemia, and the clinical course of human p. falciparum malaria. | 1991 | 1858827 |
| comparative susceptibility of anopheline mosquitoes to plasmodium falciparum in rondonia, brazil. | five anopheline species, anopheles deaneorum, an. albitarsis, an. triannulatus, an. oswaldoi, and an. mediopunctatus were compared to an. darlingi for susceptibility to infection by p. falciparum in costa marques, rondonia, brazil. laboratory reared f1 an. darlingi and anopheline test species were allowed to feed at the same time on falciparum malaria patients who had gametocytes in their blood, and who had not yet been treated with quinine. mosquitoes were dissected and examined for oocysts on ... | 1991 | 1858963 |
| infection of anopheles darlingi fed on patients with plasmodium falciparum before and after treatment with quinine or quinine plus tetracycline. | anopheles darlingi fed on eight falciparum malaria patients with gametocytes before and after treatment with quinine sulfate or quinine sulfate plus tetracycline became infected. quinine and quinine plus tetracycline had no apparent sporontocidal or gametocytocidal effect on late stage immature and mature gametocytes. plasmodium falciparum gametocytes are persistent and infected mosquitoes for up to 21 days after patients were treated with quinine plus tetracycline. sporogonic development was si ... | 1991 | 1858964 |
| resistance to antimalarials by plasmodium falciparum in arso pir, irian jaya, indonesia. | between 1987 and 1990, susceptibility of plasmodium falciparum to chloroquine and to fansidar was measured in vivo in 151 volunteers using the standard 7-day test. all volunteers lived in arso pir, irian jaya. a 25 mg/kg dose of chloroquine base was administered over a three-day period to 92 volunteers positive for p. falciparum rings (greater than 10 rings/200 white blood cells). fifty volunteers (54%) showed results consistent with resistance. twenty-nine were classified rii, and 21 riii. in n ... | 1991 | 1858967 |
| plasmodium falciparum polypeptides interacting with human red cell membranes show high affinity binding to band-3. | p. falciparum proteins were labelled with [35s]methionine and harvested at various asexual stages. a number of parasite proteins bound to uninfected red cell membranes (ghosts). some of these proteins differentially partitioned when ghosts were extracted with detergent. several of these proteins bound very strongly to immobilised whole ghost proteins or immobilised purified band-3 in a stage-specific manner, but not to a sham-coupled matrix or to immobilised band-3 extract from cells rendered re ... | 1991 | 1859852 |
| rosetting of plasmodium falciparum-infected red blood cells with uninfected red blood cells enhances microvascular obstruction under flow conditions. | the occurrence of rosetting of plasmodium falciparum-infected human red blood cells (irbc) with uninfected red blood cells (rbc) and its potential pathophysiologic consequences were investigated under flow conditions using the perfused rat mesocecum vasculature. perfusion experiments were performed using two knobby (k+) lines of p falciparum, ie, rosetting positive (k+r+) and rosetting negative (k+r-). the infusion of k+r+ irbc resulted in higher peripheral resistance (pru) than k+r- irbc (p les ... | 1991 | 1859893 |
| pharmacokinetics and pharmacodynamics of mefloquine in thai patients with acute falciparum malaria. | a double-blind randomized comparative study of the pharmacokinetics and pharmacodynamics of a single oral dose of 750 mg or 1250 mg of mefloquine was carried out on 20 thai male patients with acute uncomplicated falciparum malaria. in the 750-mg group, one patient exhibited an rii response, while the others responded to the treatment with a mean fever clearance time of 50.2 +/- 28.2 hours and a mean parasite clearance time of 70.2 +/- 17.3 hours. the main adverse effects were dizziness, nausea, ... | 1991 | 1860148 |
| reversed siderophores act as antimalarial agents. | we describe here a family of biomimetic iron carriers that display high binding efficiency for ferric ions and favorable permeation properties across erythrocytic membranes. these carriers inhibit in vitro growth of plasmodium falciparum by scavenging intracellular iron. the chemical features were realized by reproducing the iron-binding cavities of natural iron carriers (siderophores) and by systematic substitutions of their hydrophilic envelopes for more hydrophobic ones. in contrast to natura ... | 1991 | 1862083 |
| [malaria. quid novi?]. | | 1991 | 1863604 |
| determination of genetic variation within plasmodium falciparum by using enzymatically amplified dna from filter paper disks impregnated with whole blood. | a new method which allows the enzymatic amplification of dna extracted from whole blood dried on filter paper disks is presented. the method was used to study heterogeneity within an erythrocyte-binding antigen (eba-175) of plasmodium falciparum. blood specimens from malaria-infected patients in southeast asia and africa were spotted onto filter paper, dried, and transported for processing. p. falciparum dna was extracted by boiling the filter paper disks in the presence of chelex-100 ion-chelat ... | 1991 | 1864936 |
| detection of antigens and antibodies in the urine of humans with plasmodium falciparum malaria. | humans infected with plasmodium falciparum frequently have elevated levels of proteins in their urine, but it is unclear if any of these proteins are parasite antigens or antimalarial antibodies. to resolve this question, urine samples from malaria patients and controls living in thailand and ghana were evaluated. urine samples from 85% of the patients had elevated protein levels and contained proteins with mrs ranging from less than 29,000 to greater than 224,000 as determined by sodium dodecyl ... | 1991 | 1864942 |
| infection of aotus vociferans monkeys with different strains of plasmodium falciparum. | twenty-one splenectomized aotus vociferans monkeys were infected with the different strains/clones of plasmodium falciparum. maximum parasitemia ranged from 1,302 to 1,460,000 parasites per mm3. only the santa lucia strain was shown to produce gametocytes for extended periods. gametocytes produced during the primary episode of parasitemia were highly infective to anopheles freeborni mosquitoes. gametocytes produced during recrudescence were not infective to mosquitoes feeding directly on the ani ... | 1991 | 1865263 |
| common west african hla antigens are associated with protection from severe malaria. | a large case-control study of malaria in west african children shows that a human leucocyte class i antigen (hla-bw53) and an hla class ii haplotype (drb1*1302-dqb1*0501), common in west africans but rare in other racial groups, are independently associated with protection from severe malaria. in this population they account for as great a reduction in disease incidence as the sickle-cell haemoglobin variant. these data support the hypothesis that the extraordinary polymorphism of major histocom ... | 1991 | 1865923 |
| cytoadherence of knobby and knobless plasmodium falciparum-infected erythrocytes. | cytoadherence of plasmodium falciparum-infected erythrocytes to melanoma cells was analysed using strains or isolates of parasites expressing or not expressing knobs (k+ or k- phenotype) on the erythrocyte surface. both k+ and k- parasites had the capacity to cytoadhere to melanoma cells. using a panel of melanoma cell lines with different surface expression of the cytoadherence receptors cd36, thrombospondin and icam-1 indicated that cd36 was the major receptor for parasites of both k+ and k- p ... | 1991 | 1866180 |
| structure and possible function of plasmodium falciparum proteins exported to the erythrocyte membrane. | on infecting the red blood cell, the malaria parasite plasmodium falciparum induces alterations in the erythrocyte membrane. the parasite appears to synthesize proteins that are exported across the parasitophorous vacuole membrane and through a system of membraneous structures within the cytoplasm of the host cell to the surface membrane of the erythrocyte. there, these proteins are either released or remain associated with the membrane. in this review we describe the structure and discuss the p ... | 1991 | 1866416 |
| pyrimethamin-resistant plasmodium falciparum lack cross-resistance to methotrexate and 2,4-diamino-5-(substituted benzyl) pyrimidines. | methotrexate resistance induced in cultured plasmodium falciparum depends on an altered dihydrofolate reductase with decreased affinity for methotrexate as well as for pyrimethamine. in contrast, pyrimethamine-resistant field isolates of p. falciparum lack cross-resistance to methotrexate and 2,4-diamino-5-(substituted benzyl) pyrimidines. the structure of the latter class was optimized by the use of trimethoprim as a lead and the substitution of methoxy groups at the benzyl ring by 3-(4'-aminop ... | 1991 | 1866423 |
| lymphoproliferative responses to plasmodium falciparum antigens in children with and without the sickle cell trait. | blood mononuclear cells (bmnc) were isolated from sickle cell trait (hbas) healthy donors and normal haemoglobin (hbaa) healthy donors resident in a p. falciparum endemic area of eastern sudan. blood samples were collected during the malaria season. bmnc were tested for their proliferative responses to phytohaemagglutinin (pha), purified protein derivative of tuberculin (ppd) and to soluble p. falciparum antigens (spag). higher responses to spag and ppd were observed in the hbas children compare ... | 1991 | 1866602 |
| significance of circumsporozoite-specific antibody in the natural transmission of plasmodium falciparum, plasmodium vivax, and plasmodium malariae in an aboriginal (orang asli) population of central peninsula malaysia. | two hundred and seventy-five orang asli volunteers living in nine villages in the pos legap valley of perak state, peninsular malaysia, participated in a prospective study designed to characterize the epidemiological, parasitological, and entomological characteristics of plasmodium falciparum, p. vivax, and p. malariae malaria transmission. prevalence rates for the three plasmodial species at initiation of the study ranged from 56% in the 0-4-year-old age group to 0% in individuals over the age ... | 1991 | 1867348 |
| age-dependent acquired protection against plasmodium falciparum in people having two years exposure to hyperendemic malaria. | an epidemiologic study of susceptibility to frequent and high-grade parasitemia by plasmodium falciparum revealed that age-dependent acquired protection developed within a two-year period of exposure to hyperendemic infection pressure. the study was conducted in a single village in northeastern irian jaya, indonesia, where half the residents were native to the province and the other half were transmigrants from areas of java, where there is little or no malaria transmission. five separate measur ... | 1991 | 1867349 |
| clustering of malaria infections within an endemic population: risk of malaria associated with the type of housing construction. | the occurrence of malaria infections due to plasmodium vivax and p. falciparum was monitored in a population of 3,023 people living in six contiguous villages in kataragama, an area of endemic malaria in southern sri lanka, over a period of 17 months. the annual incidence of malaria in this population during the study period was 25.8%. malaria attacks were clustered, occurring more frequently than expected in certain individuals and housing groups and less frequently than expected in others. in ... | 1991 | 1867350 |
| malaria and leishmania parasites share the knob-associated histidine-rich protein gene sequences. | 1. the main coding region of the knob-associated histidine-rich protein (kahrp) gene of plasmodium falciparum hydridized with genomic dna of leishmania donovani. 2. a total of five ecori fragments of various sizes (7.5, 5.5, 3.2, 0.75 and 0.56 kb) were recognized by this probe, under lower stringent conditions. however, under a higher stringency of washing, two of the smallest fragments were washed away. 3. out of these ecori fragments, the 5.5 kb band showed a maximum homology with the probe wh ... | 1991 | 1868683 |
| lack of correlation between red cell invasion by merozoites and anti-heat shock protein-70 antibody levels in malaria patients' sera. | a total of 172 sera samples were collected from individuals who were living in piyawli-jaitwarpur village in ghaziabad district (u.p.), india. they had suffered from falciparum malaria attack, and were cured with antimalarial drugs 1-2 weeks prior to sample collection. these samples were divided into nine groups according to their age. the pooled sera from each group were tested for the presence of anti-schizont and anti-heat shock protein (hsp)-70 antibodies, as well as for parasite growth inhi ... | 1991 | 1869355 |
| relationships between clinical protection and antibodies to plasmodium falciparum resa (ring-infected erythrocyte surface antigen) peptides. | a longitudinal study involving 76 individuals living in dafinso and vallée du kou (near bobo-dioulasso, burkina faso, west africa) was performed in june 1987 (beginning of the transmission period), august-september 1987 (during) and january 1988 (after). the serological antibody (ab) responses against synthetic peptides representing repeat amino acid sequences of the p. falciparum ring-infected erythrocyte surface antigen (resa): (eenv)5, (eenvehda)4, (ddehveeptva)2 were evaluated by elisa. the ... | 1991 | 1869365 |
| ciprofloxacin treatment of drug-resistant falciparum malaria. | a randomized, open study of high-dose ciprofloxacin (750 mg every 12 h) in uncomplicated falciparum malaria was conducted in thailand. no patient completed the planned 1-week treatment course. because of rising parasitemia (threefold higher at 36 h than on admission) and deterioration of clinical status, three individuals required quinine treatment 36 h after commencing ciprofloxacin; a fourth was given quinine at 54 h. the study was terminated early for safety reasons after only four ciprofloxa ... | 1991 | 1869847 |
| mefloquine-resistant malaria induced by inappropriate quinine regimens? | | 1991 | 1869860 |
| [detection of plasmodium falciparum using the plasmid pf rep 20 probe (preliminary report)]. | a cloned repetitive dna sequence (rep 20) labeled with 32p was evaluated as diagnostic probe for p. falciparum in 39 blood samples from hainan and yunan provinces. its specificity and sensitivity were studied and compared with total genomic dna probe isolated from p. f. hainan fcc1/hn isolate. the ppf rep 20 probe recognized the dna of p. f. hainan, yunnan and anhui isolates, but did not hybridize with the dna of p. vivax, p. cynomolgi, p. knowlesi and p. yoelii. the genomic probe hybridized wit ... | 1991 | 1873891 |
| recent studies on antimalarial efficacy of piperaquine and hydroxypiperaquine. | piperaquine and hydroxypiperaquine seem to be successful candidates of antimalarial drugs in china. their antimalarial efficacy, experimental resistance, combination, mode of antimalarial action and clinical trials are described briefly. | 1991 | 1874015 |
| a case of chloroquine resistant falciparum malaria in saudi arabia. | | 1991 | 1875086 |
| species composition of the anopheles gambiae complex (diptera: culicidae) at two sites in western kenya. | at two sites in the kisumu area of western kenya, the species composition of the anopheles gambiae complex was determined by analysis of ovarian polytene chromosomes. of 1,915 females, 26.1% were an. arabiensis patton and 73.9% were an. gambiae giles; one arabiensis x gambiae hybrid was identified. no major differences in the proportions of an. arabiensis and an. gambiae were observed between sites or between years. the ratio of an. arabiensis/an. gambiae was 6.7:1 (n = 231) in cow-baited traps, ... | 1991 | 1875359 |
| drug interaction between cyclosporine a and quinine in a renal transplant patient with malaria. | we report a previously undocumented drug interaction between cyclosporine a and quinine. a 39 year old asian with a recent renal transplant was diagnosed to have a mild cerebral falciparum malaria. he was treated with seven days of oral quinine (600 mg, 8 hourly), followed by a stat dose of pyrimethamine (75 mg)--sulfadoxime (1200mg) because of a strong suspicion of chloroquine resistant falciparum malaria. using a polyclonal radioimmunoassay method, we measured morning trough cyclosporine a lev ... | 1991 | 1876897 |
| anopheline ecology and malaria infection during the irrigation development of an area of the mahaweli project, sri lanka. | a study on adult anopheline ecology and malaria vector incrimination was carried out from 1986 to 1989 during irrigation development in an area of the mahaweli project in eastern sri lanka. eleven potential vector species were collected resting indoors or by using human or bovid bait, and from light trap catches. overall, anopheles vagus (donitz), an. annularis (van der wulp), and an. subpictus (grassi) were the most prevalent, and an. culicifacies (giles) and an. barbirostris (van der wulp) wer ... | 1991 | 1877717 |
| strain specificity in the liver-stage development of plasmodium falciparum in primary cultures of new world monkey hepatocytes. | primary cultures of aotus and saimiri monkey hepatocytes were infected with sporozoites of the plasmodium falciparum nf 54 strain from mosquitoes fed on gametocyte cultures, and with sporozoites of the p. falciparum santa lucia strain from mosquitoes fed on an infected aotus monkey. after 4-8 days, one exoerythrocytic (ee) parasite per 30,000 sporozoites was detected in one of three experiments performed with the p. falciparum nf54 strain. however, numerous ee parasites were detected in aotus an ... | 1991 | 1877718 |
| standard and reduced doses of mefloquine for treatment of plasmodium falciparum in tanzania: whole blood concentrations in relation to adverse reactions, in vivo response, and in vitro susceptibility. | fifty-three asymptomatic tanzanian school children with 400-31,000 asexual plasmodium falciparum parasites/microliter of blood were given standard, one-half, one-quarter, or one-eighth of the recommended mefloquine treatment dose of 25 mg base/kg body weight. mefloquine and main metabolite concentrations were determined in 100 microliters of capillary blood using a high performance liquid chromatographic method. in the standard, one-half, and one-quarter dose groups, all children cleared the par ... | 1991 | 1877721 |
| killing of plasmodium falciparum in vitro by nitric oxide derivatives. | we have investigated the in vitro susceptibility of the human malaria parasite plasmodium falciparum to killing by nitric oxide and related molecules. a saturated solution of nitric oxide did not inhibit parasite growth, but two oxidation products of nitric oxide (nitrite and nitrate ions) were toxic to the parasite in millimolar concentrations. nitrosothiol derivatives of cysteine and glutathione were found to be about a thousand times more active (50% growth inhibitory concentration, approxima ... | 1991 | 1879941 |
| splenic infarctions in mixed infection with kala azar and falciparum malaria. | | 1991 | 1880108 |
| interaction of sickle haemoglobin with malaria. | | 1991 | 1880113 |
| the putative mitochondrial genome of plasmodium falciparum. | intraerythrocytic stages of mammalian malarial parasites employ glycolysis for energy production but some aspects of mitochondrial function appear crucial to their survival since inhibitors of mitochondrial protein synthesis and electron transport have antimalarial effects. investigations of the putative mitochondrial genome of plasmodium falciparum have detected organellar rrnas and trnas encoded by a 35 kb circular dna. some features of the organization and sequence of the rrna genes are remin ... | 1991 | 1880762 |
| multiple display of foreign peptides on a filamentous bacteriophage. peptides from plasmodium falciparum circumsporozoite protein as antigens. | we describe here two systems for encoding foreign amino acid sequences in the exposed n-terminal segment of the major coat protein of bacteriophage fd. small peptides can be encoded directly; larger peptides are encoded in hybrid bacteriophage particles, in which the capsid is formed from a mixture of wild-type and modified coat proteins. in both cases, the peptides are present in multiple copies per phage particle. peptides that represent the circumsporozoite protein, the major surface antigen ... | 1991 | 1880799 |
| can ethnopharmacology contribute to the development of antimalarial agents? | the resistance of plasmodium falciparum, the cause of tertian malaria, to synthetic antimalarials, together with the resistance of the vector mosquitoes to insecticides, has resulted in a resurgence in the use of quinine and a search for new antimalarial agents. in recent years, artemisinin, isolated from artemisia annua which is used in chinese traditional medicine for the treatment of malaria, has proved to be effective in the treatment of cerebral malaria due to chloroquine-resistant strains ... | 1991 | 1881153 |
| birds of a fever. | | 1991 | 1882225 |
| wide distribution of the variant form of the human malaria parasite plasmodium vivax. | we have found polymorphism in the repetitive and nonrepetitive regions of the sporozoite vaccine antigen, the circumsporozoite (cs) protein, in plasmodium vivax malaria parasites from two geographically distant malaria endemic regions of the world. like the recently described variant repeat sequence of p. vivax from thailand, the cs protein repeat sequence of the variant p. vivax parasites from papua new guinea and brazil is anga(g/d)(n/d)qpg, which differs from the previously identified cs repe ... | 1991 | 1885563 |
| optimization of a rapid nonisotopic dna probe assay for plasmodium falciparum in the gambia. | an enzyme-linked synthetic dna probe which hybridizes to repetitive dna of plasmodium falciparum was used in conjunction with a microtiter-based lysis and filtration blood processing procedure. an assay protocol was developed that is more sensitive and robust than previous protocols, which use stored blood and phenol extraction. in comparison with thick smear examination, 33% positive, 60% negative, and 7% conflicting scores were recorded from 390 analyzed clinical samples, and the sensitivity t ... | 1991 | 1885747 |
| severe hyponatraemia in malaria. | we report a case of severe hyponatraemia and hypoglycaemia in a patient with complicated falciparum malaria. the use of large volumes of intravenous dextrose as a diluent for quinine may lead to fluid overload and exacerbate hyponatraemia. | 1991 | 1885920 |