| recognition of plasmodium falciparum asexual stage antigens by antibodies in sera from people exposed to plasmodium vivax. | an analysis of plasmodium falciparum antigen-specific antibodies was performed on 44 serum samples from guatemala, a region endemic for p. vivax. most sera showed positive reactivity to p. falciparum asexual stage antigens by indirect immunofluorescent assay, enzyme-linked immunosorbent assay, and immunoprecipitation analysis using biosynthetically labeled parasites. although several antigens were recognized by these sera, proteins with molecular weights of 195 kd, 140 kd, and in the range of 70 ... | 1992 | 1279995 |
| molecular analysis of the association of hla-b53 and resistance to severe malaria. | the protective association between the human leukocyte antigen hla-b53 and severe malaria was investigated by sequencing of peptides eluted from this molecule followed by screening of candidate epitopes from pre-erythrocytic-stage antigens of plasmodium falciparum in biochemical and cellular assays. among malaria-immune africans, hla-b53-restricted cytotoxic t lymphocytes recognized a conserved nonamer peptide from liver-stage-specific antigen-1 (lsa-1), but no hla-b53-restricted epitopes were i ... | 1992 | 1280333 |
| peptides reactive with a transmission-blocking monoclonal antibody against plasmodium falciparum pfs25: 2000-fold affinity increase by pepscan-based amino acid substitutions. | based on pepscan analyses, a peptide derived from the 25-kda surface protein of p. falciparum sexual stages (ldtsnpvkt, amino acids 122-130) was recently shown to react with transmission-blocking monoclonal antibodies. subsequently, a pinbound construct (fddtdpikk; six amino acids substituted) was designed that reacted 1000 times better with the transmission-blocking monoclonal antibody 32f81 than with the parent ldtsnpvkt peptide. while this construct was obtained through single amino acid repl ... | 1992 | 1280492 |
| world malaria situation 1990. division of control of tropical diseases. world health organization, geneva. | malaria risk of varying degree exists in 99 countries or areas. however, falciparum malaria does not exist or its relative prevalence is less than 1% in 13 of these countries. accurate information on the global incidence of malaria is difficult to obtain because reporting is particularly incomplete in areas known to be highly endemic. the global incidence of malaria is estimated to be nearly 120 million clinical cases each year, with nearly 300 million people carrying the parasite. 90% of the to ... | 1992 | 1281364 |
| diversity in the immunodominant determinants of the circumsporozoite protein of plasmodium falciparum parasites from malaria-endemic regions of papua new guinea and brazil. | to determine the nature and extent of variation in the t cell sites of the plasmodium falciparum circumsporozoite (cs) protein, a candidate antigen in the development of a malaria vaccine, we cloned and sequenced 69 recombinant clones of the cs protein gene representing 18 and 17 p. falciparum isolates from infected individuals from madang, papua new guinea (png), a holoendemic malaria region, and paragaminos and jacunda, brazil, relatively low endemic regions, respectively. as previously known, ... | 1992 | 1281968 |
| anomalous reversed-phase high-performance liquid chromatographic behavior of synthetic peptides related to antigenic helper t cell sites. | sets of overlapping synthetic peptides for three well characterized proteins (sperm whale myoglobin, hen egg lysozyme, and the circumsporozoite protein from plasmodium falciparum) were prepared and examined by reversed-phase high-performance liquid chromatography (rp-hplc). using retention coefficients to predict the retention time of each peptide, several peptides in each protein set were found that exhibited anomalous behavior (i.e. eluted significantly later than predicted). previous work wit ... | 1992 | 1282129 |
| serum protein concentrations in plasmodium falciparum malaria. | in patients with uncomplicated plasmodium falciparum infection cytokine-mediated serum protein levels of c-reactive protein (crp), coeruloplasmin (coe), beta 2-microglobulin (b2m), alpha 1-acid glycoprotein (aag), alpha 1-antitrypsin (aat), haptoglobin (hpt), prealbumin (pre), retinol binding protein (rbp), albumin (alb) and transferrin (trf) were measured in an endemic area of the amazonian rain forest. semi-immune (si) and nonimmune (ni) patients were investigated. in both patient groups the s ... | 1992 | 1283805 |
| plasmodium falciparum invades human red cells via a parasite produced glycosidase. | this report describes that p. falciparum produces a neuraminidase like activity on invasion into erythrocytes in culture on the basis of biochemical and immunological investigations. this activity in turn modifies the surface glycoprotein receptors of red cells and may be of help in the inhibition of further invasion by merozoites. the characterization of this enzyme activity may help elucidate the mechanism of cerebral malaria. | 1992 | 1284053 |
| plasmodium falciparum cs protein--prime malaria vaccine candidate: definition of the human ctl domain and analysis of its variation. | studies in mice have shown that immunity to malaria sporozoites is mediated primarily by cytotoxic t lymphocytes (ctl) specific for epitopes within the circumsporozoite (cs) protein. humans, however, had never been shown to generate ctl against any malaria or other parasite protein. the design of a sub-unit vaccine for humans relies on the epitopes recognized by ctl being identified and polymorphisms therein being defined. we have developed a novel technique using an entire series of overlapping ... | 1992 | 1285314 |
| molecular mechanisms and biological importance of plasmodium falciparum erythrocyte rosetting. | rosetting, i.e. the spontaneous binding of uninfected to malaria infected erythrocytes and endothelial cytoadherence may hinder the blood flow and lead to severe plasmodium falciparum malaria. falciparum isolates obtained from unconscious patients all form rosettes and/or express a significantly higher mean rosetting rate than isolates from patients with uncomplicated malaria. furthermore, sera of patients with cerebral malaria are devoid of anti-rosetting activity while sera from patients with ... | 1992 | 1285315 |
| malaria in the who southeast asia region. | malaria endemic countries in the southeast asia region include bangladesh, bhutan, india, indonesia, maldives, myanmar, nepal, sri lanka, and thailand. population movement and rapid urbanization, both largely caused by unemployment, and environmental deterioration change the malaria pattern. they also increase the incidence of drug-resistant malaria, especially resistance to 4-aminoquinolines. in india, plasmodium falciparum is linked to the density and distribution of tribals, and, in southe ... | 1992 | 1286730 |
| a longitudinal study to monitor chloroquine-resistant p. falciparum malaria in bokajan and manja phc areas of karbi anglong district, assam. | in-vivo as well as in-vitro studies were carried out at regular intervals from 1979 to 1988 to monitor chloroquine resistance in p. falciparum in bokajan and manja phc of karbi anglong district, assam. the results showed no significant change in resistance status in the area. intensified antivector measures, withdrawal of chloroquine pressure and prompt detection and treatment of p. falciparum cases with alternative drugs helped bring down the higher grades of resistant parasites by 1984, which ... | 1992 | 1286733 |
| report of three cases of p. falciparum showing moderately high parasitaemia. | | 1992 | 1286736 |
| comparison of artemisinin suppositories with intravenous artesunate and intravenous quinine in the treatment of cerebral malaria. | seventy-nine comatose cerebral malaria patients given standard supportive treatment were randomized to receive specific antimalarial chemotherapy of intravenous quinine, intravenous artesunate, or artemisinin suppositories. artesunate and artemisinin reduced peripheral asexual parasitaemia significantly more rapidly than quinine (90% clearance time 16 h, 18.9 h and 34.5 h respectively), but did not significantly reduce the duration of coma or mortality. the rapid lowering of peripheral parasitae ... | 1992 | 1287904 |
| norfloxacin is not effective for treatment of plasmodium falciparum infection in kenya. | | 1992 | 1287906 |
| chloroquine-resistant plasmodium falciparum isolates from the sudan lack two mutations in the pfmdr1 gene thought to be associated with chloroquine resistance. | isolates of plasmodium falciparum from 3 areas of the sudan were recovered from cryopreservation in london and their chloroquine sensitivity was determined in vitro. chloroquine resistance was detected in 6/6 isolates from khartoum, 1/4 from sennar and 3/3 from gadarif, indicating that resistance is spreading. all the isolates were sensitive to mefloquine. studies using blood spots on glass fibre discs and the polymerase chain reaction did not detect two mutations in the pfmdr1 gene, thought to ... | 1992 | 1287907 |
| the effects of multiplication and synchronicity on the vascular distribution of parasites in falciparum malaria. | the sequestration of erythrocytes containing mature forms of plasmodium falciparum in the microvasculature of vital organs may cause large discrepancies between the peripheral blood parasite count and the total body parasite burden in falciparum malaria. despite this, parasitaemia is widely used as an indicator of prognosis and response to treatment. a simple mathematical model describing the changes in circulating and sequestered parasite numbers during acute falciparum malaria is presented. th ... | 1992 | 1287908 |
| polymorphonuclear leucocyte elastase in plasmodium falciparum malaria. | sixty-one patients with falciparum malaria were studied prospectively to determine the plasma concentrations of the lysosomal proteinase, polymorphonuclear leucocyte elastase (pmn-elastase) and their relationship to disease severity. the patients were divided into 3 groups; severe (parasitaemia > 5%) or vital organ dysfunction (n = 23), moderate (parasitaemia 1%-5% without complications) (n = 15), and mild (parasitaemia < 1%) (n = 23). the mean plasma pmn-elastase level in 10 healthy thai volunt ... | 1992 | 1287909 |
| delayed cerebellar ataxia following falciparum malaria: lack of evidence for antibody mediation. | | 1992 | 1287911 |
| demonstration by the polymerase chain reaction of mixed plasmodium falciparum and p. vivax infections undetected by conventional microscopy. | mixed malaria infections (plasmodium falciparum and p. vivax) are suspected to occur at a greater frequency than is detected by conventional light microscopy. to determine this frequency we carried out a prospective 'blinded' comparison of diagnosis by conventional light microscopy and enzymatic amplification of the circumsporozoite gene extracted from dried spotted blood samples. patients were previously healthy, active duty thai soldiers assigned to a malaria risk area presenting with malaria. ... | 1992 | 1287912 |
| rna probe detection of plasmodium falciparum parasitaemia. | | 1992 | 1287913 |
| role of anopheles culicifacies sibling species in malaria transmission in madhya pradesh state, india. | | 1992 | 1287914 |
| in vitro activity of pyronaridine against african strains of plasmodium falciparum. | the in vitro activity of pyronaridine was determined and compared with the activity of monodesethylamodiaquine and amopyroquine against 31 clinical isolates and two clones of plasmodium falciparum originating from central and west africa using a semi-micro drug susceptibility test. pyronaridine and amopyroquine were 2.5 and four times less active, respectively, against the highly chloroquine-resistant clone, than against the chloroquine-susceptible clone but were equally active against chloroqui ... | 1992 | 1288425 |
| the chemotherapy of rodent malaria. xlvii. studies on pyronaridine and other mannich base antimalarials. | the activities of mannich base antimalarials, including pyronaridine, have been explored against drug-sensitive (plasmodium berghei n) and chloroquine-resistant (plasmodium yoelii ns) rodent malaria parasites in vivo. lines of these parasites have been developed with resistance to pyronaridine, amodiaquine, or wr 228,258. the responses and patterns of cross-resistance of these lines to mannich bases and other blood schizontocides are inconsistent. it is concluded that some mannich bases may prov ... | 1992 | 1288426 |
| treatment of chloroquine-resistant malaria in monkeys with a drug combination that reverses resistance in vitro. | compounds that inhibit the p-glycoprotein-related efflux mechanism of multidrug-resistant cells reverse chloroquine resistance in vitro. hence, the co-administration of chloroquine and an efflux-blocking drug could potentially treat chloroquine-resistant malaria infections. we administered a drug combination (chloroquine and a tiapamil analogue), that has been shown to reverse chloroquine resistance in vitro, to aotus monkeys but failed to safely clear experimentally-induced chloroquine-resistan ... | 1992 | 1288427 |
| flow cytometry to evaluate the parasitemia of plasmodium falciparum. | the resistance of plasmodiums to the current antimalarial agents has spurred the search for new active molecules of vegetal origin or chemical synthesis. the screening of antimalarial molecules "in vitro" was done by simple but tedious techniques such as quantification of parasitemia through optical microscopy or by using radioactive markers. we have developed a new method to evaluate parasitemia by using the odam atc 3000 flow cytometer and biological cell sorter. we selected the ethidium bromi ... | 1992 | 1289491 |
| malaria prophylaxis: taking aim at constantly moving targets. | the prevention of malaria infections is one of the most important functions that any clinician can perform for those traveling to tropical geographic regions where malaria risks are present. the prophylaxis question has become complicated by continued emergence of chloroquine-resistant strains of plasmodium falciparum, the recent appearance of plasmodium vivax resistance, and the availability of a wide choice of antimalarial pharmaceuticals. chemoprophylaxis may produce different toxicities amon ... | 1992 | 1290274 |
| studies on the effect of tunicamycin on erythrocytic stages of plasmodium falciparum. | | 1992 | 1290509 |
| death from a severe case of plasmodium falciparum in a canadian. | | 1992 | 1291016 |
| sensitivity status of plasmodium falciparum to chloroquine, amodiaquine, quinine, mefloquine and sulfadoxine/pyrimethamine in a tribal population of district sundargarh, orissa. | in a malaria-endemic area of orissa, wherein chloroquine has been in use for over thirty years, 58.3% (14/24) p. falciparum cases did not respond to single dose chloroquine (10 mg base/kg) in in-vivo test. with standard dose (25 mg base/kg) 31.2% cases (10/32) showed resistance, i.e. at ri (15.6%), rii (9.4%) and riii (6.2%) levels. standard dose was superior in response to the single dose therapy [p < 0.05; chi 2 (df 1) = 4.11]. out of eight isolates tested in vitro, two showed resistance to ch ... | 1992 | 1291342 |
| [efficacy of radical treatment with halofantrine on the prevention of imported plasmodium falciparum malaria]. | we carried out in 1989 a non randomized comparative study in french army units which had been in central africa (central african republic and gabon) for 4 months, in order to compare in 758 men on return from malaria areas the usual strategy of chemoprophylaxis with chloroquine and a radical cure by halofantrine (halfan). chloroquine was taken by 278 men (100 mg daily for 6 weeks after their return to france); the other 480 men were given two doses of 1,500 mg halofantrine on the third and on th ... | 1992 | 1292422 |
| [imported malaria in brest hospitals from 1981 to 1990]. | from 1981 to 1990, 96 confirmed hospital cases of imported malaria occurred in brest. an important increasing of the annual number was observed in 1986. a high proportion of infection was due to plasmodium falciparum, mainly from black africa. most of the patients was french young men, without or with inadequate chemoprophylaxis. every case of malaria due to p. falciparum appeared during the 2 months following their return from an endemic area. two patients had a clinical profile of visceral evo ... | 1992 | 1292795 |
| [the clinical manifestations of tropical malaria in local inhabitants and europeans in the republic of guinea (western africa)]. | | 1992 | 1293838 |
| antimalarial activity of sesquiterpenes from the marine sponge acanthella klethra. | five sesquiterpenoids containing isonitrile or isothiocyanate groups were isolated from the sponge acanthella klethra. compounds 1 and 2 were identified as axisonitrile 3 and the corresponding isothiocyanate derivative, respectively. compounds 3-5 were found to be eudesmane sesquiterpenes. none of these compounds was cytotoxic toward cultured kb-3 cells, but varying degrees of activity were observed with cultured plasmodium falciparum. compound 1 demonstrated greatest promise as an antimalarial ... | 1992 | 1294700 |
| [structural studies of malaria vaccine]. | malaria still remains a serious health problem in large areas of the world, and in this article, recent research progress mainly made by us toward malaria vaccine development has been reviewed. 1) peptide vaccines (antigens) of immunodominant tetrapeptide repeats (nanp and nvdp) of the circumsporozoite surface protein of the malaria parasite, plasmodium falciparum, were genetically produced in e. coli as a fusion protein with a part of human growth hormone, which has affected on the conformation ... | 1992 | 1294714 |
| drug resistance in malaria: a review of the west african situation. | chloroquine-resistant plasmodium falciparum malaria is an emerging problem in the west african subregion. while chloroquine remains an effective antimalarial agent in some countries of west africa, the susceptibility patterns of p falciparum strains need to be assessed periodically. this article reviews the literature on chloroquine-resistant p falciparum malaria. | 1992 | 1296994 |
| epidemiological study of malaria in north sulawesi, indonesia by fluorescence and giemsa staining. | an epidemiological study of malaria infection was conducted in the likupang district, minahasa regency, north sulawesi province, indonesia, during august 2-15, 1991. in this study, 510 people of six villages, representing ages between 1 month to 84 years cooperated voluntarily. blood smears stained with giemsa and acridine orange (ao), revealed 33 and 83 malaria parasite positives respectively. this significant difference was due particularly to the fact that ao staining examined under either a ... | 1992 | 1297003 |
| seroepidemiological studies of malaria in different endemic areas of indonesia. | a total of 618 sera from inhabitants living in various endemic areas in indonesia were examined for igg against plasmodium falciparum utilizing young trophozoites and mature schizonts as antigens by the method of elisa and ifat. in general, antibodies against trophozites (resa) based on elisa and antibodies against schizonts based on ifat showed a correlation of malarial antibodies with the level of endemicity of the area examined. anti-resa antibody, detected either by elisa or ifat was more pr ... | 1992 | 1298062 |
| epidemiology and control of malaria in malaysia. | in spite of more than 30 years of control activities, malaria continues to be the most important parasitic infection in malaysia, accounting for 39,189 confirmed cases in 1991, giving an annual parasite incidence rate of 2.2 per 1,000 population. some factors contributing to the continued transmission of malaria are the development of drug resistant plasmodium falciparum, changes in vector behavior, and ecological changes due to socio-economic reasons. malaria parasite rates are higher among the ... | 1992 | 1298064 |
| drug resistant malaria, with special reference to thailand. | drug resistance of malaria parasites is a major problem confronting efforts to treat and control malaria. starting with chloroquine, the emergence of resistance to other drugs has led to multi-drug resistance patterns that pose increasing threats for the future. this report reviews work carried out over the past decades at the hospital for tropical diseases, bangkok, which monitors patients from many areas, including the thai-cambodian border, which harbors the world's most severe multi-drug res ... | 1992 | 1298068 |
| neurological complications of malaria. | this paper reviews the neurological complications of malaria. cerebral malaria, the acute encephalopathy which complicates exclusively the infection by plasmodium falciparum commonly affects children and adolescents in hyperendemic areas. plugging of cerebral capillaries and venules by clumped, parasitized red blood cells causing blood sludging in the capillary circulation is one hypothesis to explain its pathogenesis. the other is a humoral hypothesis which proposes a nonspecific, immune-mediat ... | 1992 | 1298073 |
| detection of circulating plasmodial antigens in human sera by sandwich elisa with monoclonal antibodies. | two monoclonal antibodies (mabs), one produced against plasmodium falciparum (pf-ig8) and the other against p. cynomolgi (pc-ie12) schizont antigens were used in a sandwich elisa for the detection of circulating plasmodial antigens in sera of patients infected with either p. falciparum, p. vivax or p. malariae. the mean +/- sd optical density (od) values for the normal control group using pf-108 and pc-1e12 were 0.351 +/- 0.036 and 0.205 +/- 0.044, respectively. mean od values for the three infe ... | 1992 | 1298082 |
| two-site pan-species monoclonal antibody elisa for detection of blood stage malaria antigen. | a two-site pan-species monoclonal antibody sandwich elisa (mab-mab elisa) was developed to detect both plasmodium vivax and p. falciparum antigens in whole blood impregnated on filter paper. in this assay, the plates were coated with pan-species mab 3f9 and another pan-species mab m26-32 conjugated with alkaline phosphatase was used for detection of bound antigen. the sensitivity of this assay was 5, 10 and 10 parasites per 10(6) erythrocytes for cultured p. falciparum, patient-derived p. vivax ... | 1992 | 1298083 |
| antibody detection elisas for malaria diagnosis. | parasite extracts of plasmodium falciparum and p. chabaudi and three synthetic peptides from the p. falciparum msa2 merozoite antigen were tested for suitability as antigens in an antibody detection elisa using sera from malaria patients in brisbane. the p. chabaudi extract was superior to p. falciparum extract for detecting p. vivax cases, while for p. falciparum cases the two parasite extracts were equivalent. single peptide antigens were generally less sensitive than parasite extracts; howeve ... | 1992 | 1298085 |
| [the resistance of plasmodium falciparum strains to preparations of the 4-aminoquinoline series in the republic of guinea]. | in vivo measurements of p. falciparum sensitivity to chloroquine diphosphate, carried out in the republic of guinea, resulted in isolation of strains with degrees i and ii resistance from 5 of the 25 examined patients, that may be due to a wide prophylactic administration of the drug to all patients with fevers without completing the course of therapy in all the patients infected. such courses are obligatory to prevent the dissemination of chloroquine-resistant strains of the parasite and augmen ... | 1992 | 1299758 |
| persistence of low levels of plasmodium falciparum resistance to chloroquine in the autochthonous population of the central african republic. | in central african republic, the first cases of resistant p. falciparum to chloroquine occurred in 1983 in non immune expatriate residents on regular chemoprophylaxis. from 1984 to 1991, 950 in vivo tests with a seven days observation period were performed in semi-immune autochtonous children living in seven towns of the country. chloroquine treatments were given at 25 mg/kg over 3 days period to children with p. falciparum parasitaemia > 500 (634 simplified methods) or > 1000/mm3 (316 who stand ... | 1992 | 1300352 |
| [alteration in resistance of plasmodium falciparum to chloroquine after cessation of chloroquine medication for twelve years]. | in view of the fact the resistance of plasmodium falciparum to chloroquine occurred extensively in hainan, a decision was made in 1979 that the use of chloroquine should be quit in the whole province. a longitudinal survey on chloroquine-sensitivity of p. falciparum was carried out during 1981-1991 to observe the variation in resistance of the parasite after the cessation of the chloroquine medication for every 2-3 years. a tendency of progressive decline of resistance was revealed. by using in ... | 1992 | 1303327 |
| malarial hepatitis: a heterogeneous syndrome? | the incidence of malarial hepatitis in patients with plasmodium falciparum infection and jaundice is not known and it is not clear whether the condition is a single entity or a heterogeneous syndrome. | 1992 | 1304265 |
| mefloquine-sulphadoxine-pyrimethamine (fansimef, roche) in the prophylaxis of plasmodium falciparum malaria: a double-blind, comparative, placebo-controlled study. | from july 1987 to june 1988 a randomized, double-blind, comparative placebo-controlled field trial was conducted in a group of villages near ibadan, nigeria. the aim of the study was to assess the suppressive tolerability and efficacy of four antimalarials (fansimef, lariam, fansidar, chloroquine) given for 24 weeks. fansimef and lariam were given with loading and maintenance doses, fansidar and chloroquine as one tablet per week for 24 weeks. of 567 enrolled subjects, 114 (20%) had parasitaemia ... | 1992 | 1304698 |
| high seasonal malaria transmission rates in the intermediate rainfall zone of sri lanka. | malaria transmission was studied at nikawehera, a long-established farming village, located in the intermediate rainfall zone of sri lanka. observations were made over a 12-month period (october-september) that included the main rainy season which occurred during the north-east monsoon in november-january. anolpheles culicifacies, the recognized vector of malaria in sri lanka, was the predominant anopheline mosquito collected by human night baiting at nikawehera. high entomological inoculation r ... | 1992 | 1304700 |
| muramyl peptide adjuvants for plasmodium falciparum and plasmodium vivax circumsporozoite vaccines in rodent model systems. | circumsporozoite proteins from the malaria parasites plasmodium falciparum and plasmodium vivax were expressed at high levels in the yeast saccharomyces cerevisiae. recombinant proteins varied both in length and in number of the natural amino acid repeat motifs. the proteins were purified and used to immunize mice, guinea pigs, and rabbits. novel muramyl peptide adjuvants were used that increased the immune response as measured by elisa assays, indirect immunofluorescence of fixed sporozoites, a ... | 1992 | 1305890 |
| missense mutations and evolutionary conserved amino acids at the human hypoxanthine phosphoribosyl-transferase locus. | molecular characterization of in vivo mutation at the human hypoxanthine phosphoribosyltransferase (hprt) locus has revealed a broad spectrum of mutation, both with regard to germ-line mutation in lesch-nyhan and gout patients, and somatic mutation in 6-thioguanine resistant t-lymphocytes from healthy individuals. the pattern of missense mutation shows a non-random distribution with a preferential location to codons for amino acids which are identical in human and the two parasites schistosoma m ... | 1992 | 1306134 |
| [characterization of a surface antigen of plasmodium falciparum merozoite with monoclonal antibody]. | the monoclonal antibody (mcab) designated as c6 against erythrocytic stage of plasmodium falciparum fcc7801/hn showed significant growth inhibition of p. falciparum in vitro, having cross immunofluorescence reaction with p. falciparum fcc-1/hn, fcc7802/hn, fcc8703/js and p. berghei, p. cynomolgi. mcab c6 bound to the antigen distributed evenly over the entire surface of merozoites of p. falciparum, as demonstrated by immunoelectron microscopy. the mcab c6 also recognized a single protein of 71 k ... | 1992 | 1307271 |
| [sensitivity in vitro of plasmodium falciparum to chloroquine, pyronaridine, artesunate and piperaquine in south yunnan]. | the sensitivity of p. falciparum to chloroquine, pyronaridine, artesunate and piperaquine (cq, pd, at, pq) was assayed using in vitro microtechnique in south yunnan in 1990. the resistance rates were 98.7% (75/76), 27.6% (16/58), 13.8% (9/65) and 97.7% (43/44) respectively, and id50 were 125.0, 19.0, 4.7 and 243.3 nmol/l, respectively. the resistance rate against cq showed no change as compared to the rates against cq 5 and 9 years ago; but the id50 was lower. cq-resistant p. falciparum showed a ... | 1992 | 1307275 |
| neurological manifestations of malaria. | the involvement of the nervous system in malaria is reviewed in this paper. cerebral malaria, the acute encephalopathy which complicates exclusively the infection by plasmodium falciparum commonly affects children and adolescents in hyperendemic areas. plugging of cerebral capillaries and venules by clumped, parasitized red cells causing sludging in the capillary circulation is one hypothesis to explain its pathogenesis. the other is a humoral hypothesis which proposes nonspecific, immune-mediat ... | 1992 | 1307475 |
| malarial placental infection and low birth weight babies. | two hundred and fifty six mothers and their newborns were subjected to clinical and haematological tests for the evidence of malaria. placentae of these were examined histopathologically for malarial parasites and malarial pigment. forty six placentae showed scanty malarial pigment ingested by monocytes. these appearances were associated with focal syncytial necrosis and proliferation of cytotrophoblastic cells. plasmodium falciparum was found in cord blood of six cases. the mean weight of newbo ... | 1992 | 1307763 |
| isolation and characterization of a plasmodium falciparum strain: comparative study with four described strains. | | 1992 | 1308546 |
| malaria seroepidemiology: comparison between indirect fluorescent antibody test and enzyme immunoassay using bloodspot eluates. | blood sampling on filter paper is a current practice in malaria seroepidemiological studies by indirect fluorescent antibody test (ifat). there is, however, scant comparative information about the use of bloodspot eluates for detection of malarial igg antibodies simultaneously by ifat and enzyme immunoassay (elisa). here we report data obtained by both serological methods done on 219 bloodspot eluate samples collected in a rural community in brazilian amazon basin (alto paraíso, ariquemes munici ... | 1992 | 1308565 |
| chemotherapy and immunity in opportunistic parasitic infections in aids. | parasitic diseases are endemic in parts of the tropics, but there is no convincing evidence that their prevalence or incidence is increasing due to the hiv epidemic. available scientific data on parasitic infections in patients with the acquired immunodeficiency syndrome (aids) suggests a predominance of pneumocystis carinii, toxoplasma gondii and cryptosporidium spp. for reasons which are unclear, parasitic infections such as plasmodium falciparum, strongyloides stercoralis and entamoeba histol ... | 1992 | 1308934 |
| a malaria invasion receptor, the 175-kilodalton erythrocyte binding antigen of plasmodium falciparum recognizes the terminal neu5ac(alpha 2-3)gal- sequences of glycophorin a. | plasmodium falciparum malaria parasites invade human erythrocytes by means of a parasite receptor for erythrocytes, the 175-kd erythrocyte binding antigen (eba-175). similar to invasion efficiency, binding requires n-acetylneuraminic acid (neu5ac) on human erythrocytes, specifically the glycophorins. eba-175 bound to erythrocytes with receptor-like specificity and was saturable. the specificity of eba-175 binding was studied to determine if its binding is influenced either by simple electrostati ... | 1992 | 1310320 |
| daphnetin: a novel antimalarial agent with in vitro and in vivo activity. | daphnetin is a dihydroxycoumarin that is being used in china for the treatment of coagulation disorders. it is also a chelator and an antioxidant. in vitro, daphnetin causes a 50% inhibition (ic50) of 3h-hypoxanthine incorporation by plasmodium falciparum at concentrations between 25 and 40 microm. several related compounds, such as scopoletin, 2, 3-dihydroxybenzoic acid and 3, 4-dihydroxybenzoic acid show no inhibitory activity. the antimalarial activity of daphnetin is inhibited by the additio ... | 1992 | 1311154 |
| site of action of the antimalarial hydroxynaphthoquinone, 2-[trans-4-(4'-chlorophenyl) cyclohexyl]-3-hydroxy-1,4-naphthoquinone (566c80). | the site of action of the antimalarial compound 2-[trans-4-(4'-chlorophenyl) cyclohexyl]-3-hydroxy-1,4-naphthoquinone (566c80), would appear to be the mitochondrial respiratory chain. studies reported herein have demonstrated 566c80 to be a potent and selective mitochondrial inhibitor with mitochondria isolated from plasmodium falciparum and p. yoelii. selective assay of individual respiratory chain complexes has shown the primary site of action of 566c80 to be the cytochrome bc1 complex (comple ... | 1992 | 1314606 |
| plasmodium falciparum and plasmodium chabaudi: characterization of glycosylphosphatidylinositol-degrading activities. | merozoites of malaria parasites have a membrane-bound serine protease whose solubilization and subsequent activity depend on a parasite-derived glycosylphosphatidylinositol-phospholipase c (gpi-plc). the gpi-degrading activities from both plasmodium falciparum and plasmodium chabaudi have been characterized and partially purified by phenylboronate chromatography. they are membrane-bound, developmentally regulated, calcium-independent enzymes and as such they resemble gpi-plc of trypanosoma bruce ... | 1992 | 1317298 |
| the 6-kb element of plasmodium falciparum encodes mitochondrial cytochrome genes. | | 1992 | 1320735 |
| subset heterogeneity among gamma delta t cells found in peripheral blood during plasmodium falciparum malaria. | | 1992 | 1323528 |
| activity of azithromycin (cp-62,993) and erythromycin against chloroquine-sensitive and chloroquine-resistant strains of plasmodium falciparum in vitro. | several antibiotics, including the macrolide erythromycin and the azalides azithromycin (cp-62,993) and cp-63,956, that inhibit protein synthesis on 70s ribosomes demonstrated antimalarial effects in vitro against two strains of plasmodium falciparum, one sensitive to chloroquine and the other resistant. in 48-hr incubations, erythromycin was 10-fold less potent than the azalides against the chloroquine-resistant strain. erythromycin and the azalides were essentially equipotent against the chlor ... | 1992 | 1326232 |
| the basolateral domain of the hepatocyte plasma membrane bears receptors for the circumsporozoite protein of plasmodium falciparum sporozoites. | minutes after injection into the circulation, malaria sporozoites enter hepatocytes. the speed and specificity of the invasion process suggest that it is receptor mediated. we show here that recombinant plasmodium falciparum circumsporozoite protein (cs) binds specifically to regions of the plasma membrane of hepatocytes exposed to circulating blood in the disse space. no binding has been detected in other organs, or even in other regions of the hepatocyte membrane. the interaction of cs with he ... | 1992 | 1326407 |
| incorporation of free fatty acids can explain alterations in the molecular species composition of phosphatidylcholine and phosphatidylethanolamine in human erythrocytes as induced by plasmodium falciparum. | phosphatidylcholine (pc) and phosphatidylethanolamine (pe) species composition of human erythrocytes changes upon intraerythrocytic development of plasmodium falciparum. though the activity of the phosphotransferases which catalyze the last step of the kennedy pathway for the synthesis of pc and pe is dependent of the species on diacylglycerol, it appeared that this cannot, by itself, explain the alterations found in pc and pe molecular species composition. when the incorporation of radiolabeled ... | 1992 | 1327542 |
| [treatment of malaria in children in france]. | currently, most of the subjects presenting with plasmodium falciparum malaria in france come from areas where chloroquine resistance has already been reported. treatment of uncomplicated malaria should consist of oral administration of either quinine or mefloquine or halofantrine. in children, halofantrine seems to be the treatment of choice at any age. the prognosis of cerebral malaria depends on how fast the diagnosis is made and the treatment is undertaken. the detection of clinical and biolo ... | 1992 | 1331951 |
| correlation between destruction of malarial parasites by polymorphonuclear leucocytes and oxidative stress. | the role of reactive oxygen species (ros) generated by polymorphonuclear leucocytes (pmns) in the host response against malaria was investigated. non-activated human pmns were added to cultures of p. falciparum in microtitre cells. parasite viability was evaluated by the incorporation of radioactive hypoxanthine. using pmn/rbc = 1/150 (starting parasitemia was 1%) the incorporation on the second day in culture was only 61% of the control cultures. an effect could be observed already after two ho ... | 1992 | 1335429 |
| population genetics of microbial organisms. | population data suggest that many parasitic protozoa (e.g. trypanosoma, leishmania, entamoeba and giardia) reproduce clonally, but this hypothesis has been highly controversial for plasmodium falciparum. although reproduction is predominantly clonal in the enteric bacteria escherichia coli and salmonella, the level of recombination affecting short (< 1 kb) regions of the chromosome is sufficient such that many genes are obviously mosaics of different ancestries. transposable insertion sequences ... | 1992 | 1335810 |
| cloning and characterization of a novel multicopy, repetitive sequence of plasmodium falciparum, rep51. | | 1992 | 1339406 |
| [in vivo chemosensitivity of plasmodium falciparum to chloroquine in burkina faso: development of resistance 1988-1990]. | a study of plasmodium falciparum sensitivity to chloroquine was carried out in 1988 and 1990 in 5 localities, representatives of different climatic areas of burkina faso. the 7-day in vivo standard test performed in 1988 showed a total clearance failure of 25%. no significant difference with 1990 data was found, except for an increase of the resistance in the area of fada n'gourma, close to the border with benin, niger and togo. | 1992 | 1339966 |
| malaria transmission in a central area of futa djalon (guinea): results of a parasitological survey during the 1989 rainy season. | a malaria survey based on household surveys and dispensary visits without notice was carried out during the rainy season of 1989 in three selected areas of central futa djalon (republic of guinea). preliminary entomological evidence showed that anopheles gambiae was the main vector in the area with a cs positive rate of 7.6% and a human blood index of 78% in august 1989. indoor resting densities were highest in the rural village, lowest in labé and intermediate in the town of timbi madina (media ... | 1992 | 1339967 |
| [extension of the area of aedes albopictus in italy. 1st report of the species in central italy]. | a new infestation by aedes albopictus was discovered in civitavecchia, central italy, in october 1992. this follows previous records of the species in north italy, where the first infestation was observed in 1990 in the city of genoa. the present finding clearly indicates the capacity of aedes albopictus to spread all over italy and to become a permanent pest in southern europe. in spite of the expected embryonic diapause in october, larval breeding was observed in a fifteen-liter glass jar with ... | 1992 | 1339968 |
| malaria transmission in the lagoon area of cotonou, benin. | a study of the prevalence and intensity of malaria transmission in the lagunar area of benin was carried out by means of repeated cross-sectional surveys of the child population. six areas were selected: two urban areas of cotonou, three lagunar villages and one savanna village. slide positive rates and prevalence of antibodies to p. falciparum sporozoites were examined in june-july 1989 (long rainy season), october-november 1989 (short rainy season) and march-april 1990 (short dry season). para ... | 1992 | 1339969 |
| p. falciparum strain resistance to drugs. new drug trials. | | 1992 | 1340625 |
| malaria vaccines: scientific and ethical issues. | | 1992 | 1340632 |
| chemoprophylaxis against malaria in papua new guinea: a trial of amodiaquine and a combination of dapsone and pyrimethamine. | a placebo-controlled chemoprophylaxis trial was carried out in 1980 in 318 semi-immune school children in the madang area of papua new guinea, where there was a high prevalence of strains of plasmodium falciparum resistant to 4-aminoquinolines. since prophylaxis with amodiaquine at 5 mg/kg weekly had failed, amodiaquine at a dose of 10mg/kg weekly and maloprim (half a tablet or one tablet depending on body weight, which gave ranges of dapsone of 1.7-3.3mg/kg and pyrimethamine 0.2-0.4 mg/kg) week ... | 1992 | 1341089 |
| prenatal immune hypersensitization to malaria: plasmodium falciparum-specific ige antibody in paired maternal and cord sera from papua new guinea. | in a study of malaria and pregnancy in east sepik province of papua new guinea 45 maternal and cord serum pairs were tested for plasmodium falciparum-specific ige antibody. there were 17 positive sera: 6 cases of maternal serum alone, 5 cases of cord serum alone and 3 pairs of maternal and cord sera. ige antibody positivity rates in the mothers increased with parity, whereas placental parasitaemia rates decreased. cord serum positivity was not affected by parity. immunoblots of the sera revealed ... | 1992 | 1341092 |
| a randomized clinical trial with high dose of chloroquine for treatment of plasmodium falciparum malaria in brazil. | this clinical trial compared parasitological efficacy, levels of in vivo resistance and side effects of oral chloroquine 25 mg/kg and 50 mg/kg in 3 days treatment in plasmodium falciparum malaria with an extended followed-up of 30 days. the study enrolled 58 patients in the 25 mg/kg group and 66 in the 50 mg/kg group. all eligible subjects were over 14 years of age and came from amazon basin and central brazil during the period of august 1989 to april 1991. the cure rate in the 50 mg/kg group wa ... | 1992 | 1342112 |
| modern immunological approaches to assess malaria transmission and immunity and to diagnose plasmodial infection. | the present paper reviews our recent data concerning the use of immunological methods employing monoclonal antibodies and synthetic peptides to study malaria transmission and immunity and to diagnose plasmodial infection. as concerns malaria transmission, we studied the main vectors of human malaria and the plasmodial species transmitted in endemic areas of rondônia state, brazil. the natural infection of anopheline was evaluated by immunoradiometric assay (irma) using monoclonal antibodies to a ... | 1992 | 1342707 |
| virulence and the immune response in malaria. | many factors determine the virulence of a malaria infection. these include host innate resistance mechanisms and, with plasmodium falciparum, the ability to cytoadhere to endothelial cells, form rosettes, and induce release of cytokines. the effect on virulence of acquired immune responses can be determined by class i and class ii mhc-antigens; levels of immunological responsiveness may be determined too in other ways. the structure of parasite surface antigens and their great diversity modulate ... | 1992 | 1342711 |
| mechanisms of immune protection in the asexual blood stage infection by plasmodium falciparum: analysis by in vitro and ex-vivo assays. | mechanisms of immune protection against the asexual blood stage infection by plasmodium falciparum are reviewed. recent studies of two independent lines of research developed at the institut pasteur, in humans and primate infections clearly indicate an obligatory interaction of antibodies and effector cells to express the anti-parasitic effect. | 1992 | 1342712 |
| use of glass beads and cf 11 cellulose for removal of leukocytes from malaria-infected human blood in field settings. | passage of malaria-infected blood through a two-layered column composed of acid-washed glass beads and cf 11 cellulose removes white cells from parasitized blood. however, because use of glass beads and cf 11 cellulose requires filtration of infected blood separately through these two resins and the addition of adp, the procedure is time-consuming and may be inappropriate for use in the field, especially when large numbers of blood samples are to be treated. our modification of this process yiel ... | 1992 | 1343674 |
| non-phenolic method of dna purification from bacteria, blood samples and other biological sources for restriction enzyme assays and the polymerase chain reaction. | | 1992 | 1343675 |
| household-based malaria control in a highly endemic area of africa (tanzania): determinants of transmission and disease and indicators for monitoring--kilombero malaria project. | the kilombero malaria project (kmp) attempts to define operationally useful indicators of levels of transmission and disease and health system relevant monitoring indicators to evaluate the impact of disease control at the community or health facility level. the kmp is a longitudinal community based study (n = 1024) in rural southern tanzania, investigating risk factors for malarial morbidity and developing household based malaria control strategies. biweekly morbidity and bimonthly serological, ... | 1992 | 1343680 |
| immunogenicity and antigenicity of the n-term repeat amino acid sequence of the plasmodium falciparum p126 antigen. | the p126 protein, a parasitophorus vacuole antigen of plasmodium falciparum has been shown to induce protective immunity in saimiri and aotus monkeys. in the present work we investigated its immunogenicity. our results suggest that the n-term of p126 is poorly immunogenic and the antibody response against the p126 could be under a mhc restricted control in c57bl/6(h-2b) mice, which could be problematic in terms of a use of the p126 in a vaccine program. however, we observed that a synthetic pept ... | 1992 | 1343686 |
| induction of plasmodium falciparum transmission-blocking antibodies by recombinant pfs25. | | 1992 | 1343687 |
| a recombinant hybrid protein as antigen for an anti-blood stage malaria vaccine: a study on the conservation of a protective component. | recently we have shown that two hybrid proteins expressed in escherichia coli confer protective immunity to aotus monkeys against an experimental plasmodium falciparum infection (knapp et al., 1992). both hybrid proteins carry a sequence containing amino acids 631 to 764 of the serine stretch protein serp (knapp et al., 1989b). we have studied the diversity of this serp region in field isolates of p. falciparum. genomic dna was extracted from the blood of six donors from different endemic areas ... | 1992 | 1343688 |
| development of an immunoenzymatic assay using a monoclonal antibody against a 50-kda catabolite from the p126 plasmodium falciparum protein to the diagnosis of malaria infection. | the who criterion of defering any donation of blood by a confirmed case of malaria for three years after cessation of therapy can not be applied in areas where malaria is endemic. for this reason we developed an immunoenzymatic assay for the detection of plasmodial antigens for blood screening in malarial endemic areas. so, we tested sera from 191 individuals. among patients with active disease 100% of the cases of plasmodium falciparum or mixed infections and 91.7% of those with p. vivax were p ... | 1992 | 1343689 |
| antibodies in falciparum malaria: what matters most, quantity or quality? | in view of the recent demonstration that antibodies that are protective against plasmodium falciparum malaria may act in collaboration with blood monocytes, we have investigated the isotype content of sera from individuals with defined clinical states of resistance or susceptibility to malaria. profound differences in the distribution of each ig subclass and particularly in the ratio of cytophilic versus noncytophilic antibodies were found. in protected subjects, two cytophilic isotypes, igg1 an ... | 1992 | 1343695 |
| in vitro mutagenesis defines drug targets in aldolase of plasmodium falciparum. | | 1992 | 1343698 |
| mefloquine resistant malaria in cameroon and correlation with resistance to quinine. | based on the results of in vitro sensitivity of plasmodium falciparum to chloroquine, quinine and mefloquine, and evaluation of drug consumption conducted in 1987-1988 in four areas in the north and south-west of cameroon, two opposite situations were encountered in this country. in northern cameroon where mefloquine resistance is prevalent a close correlation was found between the responses of p. falciparum to mefloquine and to quinine, but not between mefloquine and chloroquine. in the south, ... | 1992 | 1343701 |
| a study on the pathogenesis of human cerebral malaria and cerebral babesiosis. | cerebral complications are important, but poorly understood pathological features of infections caused by some species of plasmodium and babesia. patients dying from p. falciparum were classified as cerebral or non-cerebral cases according to the cerebral malaria coma scale. light microscopy revealed that cerebral microvessels of cerebral malaria patients were filled with a mixture of parasitized and unparasitized erythrocytes, with 94% of the vessels showing parasitized red blood cell (prbc) se ... | 1992 | 1343706 |
| optimization and inhibition of the adherent ability of plasmodium falciparum-infected erythrocytes. | the vast majority of the 1-2 million malaria associated deaths that occur each year are due to anemia and cerebral malaria (the attachment of erythrocytes containing mature forms of plasmodium falciparum to the endothelial cells that line the vascular beds of the brain). a "model system" for the study of cerebral malaria employs amelanotic melanoma cells as the "target" cells in an in vitro cytoadherence assay. using this model system we determined that the optimum ph for adherence is 6.6 to 6.8 ... | 1992 | 1343707 |
| variation in the cytoadherence characteristics of malaria parasites: is this a true virulence factor? | the sequestration of plasmodium falciparum-infected erythrocytes to the endothelial cells of brain capillaries is believed to represent one of the determining factors in the pathogenesis of cerebral malaria. in vitro studies of cytoadherence provide an experimental approach to understand the mechanism of sequestration and the respective roles played by parasite and host components in this interaction. this paper critically reviews current studies on cytoadherence, with particular emphasis on the ... | 1992 | 1343708 |
| cytokines and dysregulation of the immune response in human malaria. | the dysregulation of the immune response by malaria parasite has been considered as a possible constraint to the effectiveness of malaria vaccination. in spite of the important role interleukin-1 (il-1) plays on the immunoregulation, and its ability to mimic various features of clinical malaria, reports on il-1 in malaria are lacking. we found that only 2 out of 35 subjects with acute malaria showed increased levels of serum il-1 alpha by enzyme immunoassay. to assess whether il-1 could interfer ... | 1992 | 1343709 |
| epidemiological distribution of plasmodium falciparum drug resistance in brazil and its relevance to the treatment and control of malaria. | with the use of a simple formulary, filled by health agents was established a monitoring programme for responses of p. falciparum to the antimalarial drugs. this monitoring programme is emphasized for the knowledge of the epidemiology of the drug resistance and the control of malaria falciparum in amazon basin where occurs more than 95% of brazilian malaria cases every year. it was demonstrated that still now 4-aminoquinolines have a great importance for the mortality control in areas where just ... | 1992 | 1343711 |
| efficacy of insecticide impregnated bed-nets to control malaria in a rural forested area in southern cameroon. | due to current spreading of chemoresistant strains of plasmodium falciparum malaria control must incorporate vector control programmes. due to well known constraints house sprayings cannot be performed as before. personal protection can be developed and a large scale use of insecticide treated bed-nets appeared to be very useful to reduce man-vector contact in asia, south america and west and east africa. no trial has been done in forest central africa where transmission is permanent. we perform ... | 1992 | 1343714 |