use of adjuvants in modulating the behaviour of plasmodium berghei. | different adjuvants were assessed for their role in conferring protection against the rodent malarial parasite p. berghei and compared with the classical freund's complete adjuvant (fca). pretreatment of mice with trehalose dimycolate (tdm) mixed with antigen (ag), sulpholipids (sl) mixed with ag, muramyl dipeptide (mdp) alone, liposomes containing ag and phosphomannoinositides (pim) mixed with ag were ineffective in conferring protection. however, mdp given with squalane (sq) and ag, mdp with i ... | 1990 | 2099325 |
dependence on cell-mediated mechanisms for the appearance of crisis forms during plasmodium chabaudi as infection in c57bl/6 mice. | the appearance of crisis forms or degenerate, intraerythrocytic parasites in the peripheral blood of c57bl/6 hosts during the course of plasmodium chabaudi as infection was analysed. following intraperitoneal injection with 10(6) parasitized erythrocytes, c57bl/6 hosts, which are resistant to this species of rodent plasmodium, eliminate the parasite from the peripheral blood by 4 weeks and recover from acute infection. elimination of the parasite coincides with the appearance in the peripheral b ... | 1990 | 2099383 |
[bacteremia caused by salmonella arizonae in a patient with malaria]. | | 1990 | 2099864 |
[the relationship between the amount of blood that mosquitoes engorge and their infectivity with the causative agent of malaria]. | the infection of mosquitoes with malaria plasmodia was found to be affected by relative (to full portion) blood amount of the infected donor, which they suck out, i.e. to what extent the engorged portion approximates to the limiting one when mosquitoes cease bloodsucking. the facts obtained show that the survival of plasmodia in a mosquito (most likely, the passing of ookinetes into the outer side of the mid-gut) is associated with the degree of its stretching during bloodsucking. the limit stre ... | 1990 | 2099999 |
chloroquine-resistant plasmodium falciparum malaria at nchelenge, northeastern zambia. follow-up on 515 hospital patients. | from 1986 until 1988 chloroquine sensitivity of plasmodium falciparum malaria was monitored in 515 hospital patients in nchelenge district, northeastern zambia. after treatment with chloroquine 30 mg base/kg, bloodslides were examined on day 2, 4, 6 and 7. the overall resistance rate was 21.4%, of which 29% was r1-, 30% r2-, 18% r3- and 23% r2-3 resistance. resistance rates were negatively correlated with age and positively with the initial parasitemia. it is suggested that in vivo tests of chlo ... | 1990 | 2100073 |
[the treatment of imported plasmodium falciparum malaria with halofantrine. apropos of 59 case reports (corrected and republished article orginally printed in med trop (mars) 1990 jan-mar;50(1):113-7)]. | 59 cases of plasmodium falciparum malaria fever occurring in non-immune caucasian subjects having got a correct chemoprophylaxis by chloroquine were treated by halofantrine (halfan). they were given 1500 mg divided in 3 doses of 500 mg every 6 hours from d1 to d8. all them were back from a malarial highly endemic zone with chloroquine resistance. analysis of the main biological and clinical efficiency parameters displayed very satisfactory results: disappearances of fever (mean 22 h) and parasit ... | 1990 | 2100512 |
clinical experience with halofantrine in the treatment of malaria. | halofantrine hydrochloride (hf) belongs to a new class of antimalarials, the phenanthrene methanols. preliminary clinical studies suggested that an adult dose of 500 mg 6-hourly for three doses, with a weight-based regimen of 8 mg/kg 6-hourly for three doses in children, would be effective. in an ongoing clinical programme, 1973 patients with acute malaria were analysed, of whom 1474 (1315 with p. falciparum and 122 with p. vivax malaria) received the above regimen. in the studies 931 adults and ... | 1990 | 2100732 |
the resistance of falciparum malaria in africa to 4-aminoquinolines and antifolates. | falciparum malaria cannot be eradicated from sub-saharan africa with present technology. the mainstay of malaria control in this situation is treatment of fever cases with chloroquine, aiming principally at reduction of mortality. the efficacy of this policy is now endangered because of the appearance and spread of chloroquine-resistance on the african continent. the present review examines laboratory and field research on the resistance of african p.falciparum to chloroquine, amodiaquine, pyrim ... | 1990 | 2100881 |
spectrophotometric assay of the interaction between malaria erythrocyte lysates with methylene blue and neutral red dyes. | changes of oxidative processes induced in mouse erythrocytes by plasmodium berghei were studied in the presence of methylene blue, neutral red or of both cationic redox dyes. the results are discussed in terms of redox and metachromatic modifications of the dyes which are produced by malarial and normal erythrocyte lysates. | 1990 | 2101204 |
[malaria in spain]. | | 1990 | 2103299 |
[induced malaria in drug addicts? a real problem in our country?]. | | 1990 | 2103300 |
[socioeconomic aspects of subjects with imported malaria in the metropolitan area of são paulo, brazil. i. characterization of the population and knowledge about the disease]. | with a view to discovering the social and economic characteristics of people from endemic malarial areas of brazil, 566 suspected malaria cases were studied at the s. paulo city metropolitan region malaria laboratory. data were obtained by means of the application of standardized questionnaires over the period from november 1986 to june 1987 to individuals with as history of transit to brazil's endemic malarial region. of the population studied, 345 (61.0%) lived in the endemic area; 479 (84.6%) ... | 1990 | 2103641 |
[malaria outbreak in users of injectable drugs]. | an outbreak of plasmodium vivax malaria among drug addicts in bauru, s. paulo state, brazil, is reported. until july 1989, 12 cases had been confirmed by thick smear examinations and 20 contacts were being investigated. all of them reported frequent use of intravenous cocaine and sharing of needles and syringes but deny having travelled through endemic malarial areas. | 1990 | 2103651 |
implications of cytokines in immunopathology: experimental and clinical data. | | 1990 | 2104242 |
[synthesis of 2-formyl (acetyl) substituted quinoline thiosemicarbazones]. | a series of 2-formyl (acetyl) substituted quinoline thiosemicarbazones (iii, xii, xiii) were prepared in order to evaluate their antimalarial activity. oxidation of substituted quinolines (iv) with selenium dioxide gave 2-formyl substituted quinolines (v). 2-acetyl substituted quinoline (ix) was obtained from iv by oxidation, esterification, claisen condensation and decarboxylation. iii1-9 were synthesized by two methods; one was by condensation of 2-formyl (acetyl) substituted quinolines with m ... | 1990 | 2104472 |
[tissue schizontocidal action and acute toxicity of trifluoroacetyl primaquine]. | trifluoroacetyl primaquine (m-8506), 6-methoxy-5-trifluoroacetyl-8-(4-methyl-butyl-amino)-aminoquinoline oxalate, synthesized by the institute of parasitic diseases was compared with primaquine for tissue schizontocidal action and acute ig ld50. in p yoelii sporozoite infected mice, the protection rates with ig m-8506 5, 10 and 20 mg (base)/kg on the day of infection were 56.7, 87.2 and 100%, respectively. these were comparable to the protection rates with primaquine 5, 10 and 20 mg(base)/kg (54 ... | 1990 | 2104491 |
rna-binding protein-related sequence in a malaria antigen, clustered-asparagine-rich protein. | members of the rna-binding protein superfamily contain rna binding domains of about 90 amino acids with a highly conserved motif 'gfgf'. using the conserved motif with some variations g-(f/y)-(g/a)-(f/y)-(v/i)-x-(f/y) as a probe, we screened protein sequences carrying identical amino acids in an nbrf-protein database. it has been found that the c-terminal portion of clustered asparagine-rich protein (carp), a malaria antigen from plasmodium falciparum, shows an unexpected sequence similarity wit ... | 1990 | 2105236 |
transmission of plasmodium vivax malaria--san diego county, california, 1988 and 1989. | | 1990 | 2105445 |
risk of malaria in british residents returning from malarious areas. | to identify which british residents travelling abroad are at greatest risk of malaria infection, and to determine the efficacy of malaria chemoprophylaxis for preventing p falciparum infections in tropical africa. | 1990 | 2107927 |
[timing niches of 3 species of plasmodium coexisting in a rodent in central africa]. | freeze-thawing of blood infected with malaria parasites is a technique which brings about the destruction of all stages except the merozoites and makes possible investigations on the behaviour of these merozoites and the schizogonic rhythm of each species. merozoites of plasmodium y. yoelii remain in the blood during the 24 hrs. following inoculation; it is concluded that their penetration in the erythrocytes occurs gradually during this time. synchronism is poor. merozoites of p. vinckei petter ... | 1990 | 2107960 |
the ring-infected erythrocyte surface antigen protein of plasmodium falciparum is phosphorylated upon association with the host cell membrane. | the ring-infected erythrocyte surface antigen (resa) is a 155-kda malarial polypeptide which is released from merozoites and becomes associated with the erythrocyte membrane at the time of invasion. inside-out vesicles (iovs) prepared from plasmodium falciparum-infected erythrocytes contain resa, presumably bound to the membrane skeleton, as it is largely insoluble in triton x-100. when these iovs were incubated with [gamma-32p]atp, a 155-kda polypeptide was labeled in iovs from infected, but no ... | 1990 | 2108327 |
antibodies to a histidine-rich protein (pfhrp1) disrupt spontaneously formed plasmodium falciparum erythrocyte rosettes. | cerebral involvement in plasmodium falciparum malaria is associated with sequestration of infected red blood cells and occlusion of cerebral vessels. adhesion of infected erythrocytes along the vascular endothelium as well as binding of uninfected erythrocytes to cells infected with late-stage asexual parasites (rosetting) may be important in erythrocyte sequestration. we report that the recently discovered rosetting phenomenon shares characteristics with other human cell-cell interactions (hepa ... | 1990 | 2108439 |
parasite antigens expressed in escherichia coli. a refined approach for epidemiological analysis. | a simple method is described to generate carrier-free recombinant antigens following their expression in escherichia coli. a plasmid, called pmsgt11, has been constructed such that the cleavage site for the protease factor xa separates the recombinant antigen from an enzymatically active beta-galactosidase. thus, rapid purification of the active beta-galactosidase recombinant protein, followed by digestion with factor xa, releases the antigen of interest. the pmsgt11 plasmid is compatible with t ... | 1990 | 2109015 |
comparison of dinucleotide frequency and codon usage in toxoplasma and plasmodium: evolutionary implications. | the weight-averaged observed/expected dinucleotide frequencies for the sum total of the coding regions of five toxoplasma genes were compared with the same parameters previously determined for the coding regions of 21 plasmodium genes. in addition, codon usage in the five toxoplasma genes was compared with that in the 21 plasmodium genes, and the percent distribution of amino acids in the toxoplasma protein pool and the plasmodium protein pool were compared with that in a general protein pool of ... | 1990 | 2111850 |
antibodies to plasmodium falciparum sporozoites following a malarial outbreak in a non-endemic area of sri lanka. | an enzyme-linked immunosorbent assay (elisa) based on the synthetic peptide (nanp)40 was used to characterize the sporozoite antibodies in an unusual plasmodium falciparum outbreak in a non-malarious area in sri lanka. a positive antibody response was seen in 62% of patients with their first p. falciparum illness. there was no correlation between sporozoite antibodies and the antibody against blood stages, determined by immunofluorescence assay. the majority (91%) of the patients lost the antibo ... | 1990 | 2111943 |
cellular and humoral immune responses to plasmodium falciparum gametocyte antigens in malaria-immune individuals. limited response to the 48/45-kilodalton surface antigen does not appear to be due to mhc restriction. | we have examined immune responses to a cultured plasmodium falciparum gametocyte lysate and to an affinity-purified preparation of the 48/45-kda gamete surface ag in a group of 30 malaria immune individuals and in 24 europeans with no previous exposure to malaria. cellular responses were assessed in vitro by lymphoproliferation and production of ifn-gamma; antigamete antibodies were detected by immunofluorescence, western blotting, and competitive elisa. cells from all the malaria immune donors ... | 1990 | 2112574 |
plasmodium falciparum: properties of an alpha-like dna polymerase, the key enzyme in dna synthesis. | an alpha-like dna polymerase has been identified and characterized in the extracts from the malarial parasite plasmodium falciparum. the enzyme is sensitive to the specific inhibitors of alpha-dna polymerase, n-ethylmaleimide and aphidicolin, and is cell-cycle specific. high activity has been found in the schizont, is lower in trophozoites, and has only negligible activity in the ring form. the enzyme has a molecular weight of about mr 100,000-103,000 estimated by detecting activity in sds-polya ... | 1990 | 2113008 |
imported malaria in italy from 1986 to 1988. | the trend of imported malaria cases in italy from 1960 to 1988 is discussed. comparative analysis of malaria incidence in the last three years is also presented. since 1985, a rapid increase was recorded with 191 cases in 1986, 287 in 1987 and 350 in 1988. in 1986-1988 plasmodium falciparum was responsible for 74% cases of the total number, followed by p. vivax (21%), p. malariae (2.2%) and p. ovale (1%). 86% of the imported cases was acquired in african countries, 8% in asia and 3% in south ame ... | 1990 | 2114489 |
production by activated human t cells of interleukin 4 but not interferon-gamma is associated with elevated levels of serum antibodies to activating malaria antigens. | t cells play a crucial role in antibody-mediated and antibody-independent immunity against plasmodium falciparum malaria. therefore, a vaccine immunogen should include parasite-derived b- and t-cell epitopes capable of giving rise to protective responses in both systems. the p. falciparum antigen pf155/ring-infected erythrocyte surface antigen (resa), a vaccine candidate, contains immunodominant t- and b-cell epitopes located in the central (5') and c-terminal (3') invariant repeat regions of th ... | 1990 | 2115172 |
irrigation, schistosomiasis, and malaria in the logone valley, cameroon. | field studies of a rice irrigation project in mayo-danai, north cameroon permitted a direct comparison between pre- and post-development data relating to schistosomiasis and malaria infection. a stratified sample of 4,000 inhabitants, representing 8% of the population living in 28 areas at the time of the first survey, was investigated 5 times between 1979 and 1985. due to the significant population increase since 1982, 1,500 persons were added to the initial sample. the prevalence of schistosom ... | 1990 | 2115305 |
continuous in-vitro cultivation of plasmodium falciparum in ibadan: solutions to scientific and logistical problems. | the technique of continuous in-vitro cultivation of plasmodium falciparum has not been widely applied in malaria-endemic areas, due to scientific as well as purely logistical problems. methods for solving or coping with these problems are described. they have already proved effective for over 4 years. the parasites harvested have been satisfactory, as judged by reproducible logarithmic growth curves and normal morphology in leishman-stained smears as well as phase-contrast microscopy of wet-prep ... | 1990 | 2115731 |
a review of antimalarial drug pyronaridine. | | 1990 | 2118061 |
progress toward a malaria vaccine. | in initial human trials, synthetic vaccines have induced humoral immunity sufficient to prevent clinical infection in some cases and delay it in others. progress in induction of cellular immunity is also noteworthy with identification of determinants recognized by t cells. antigenic variation and consequent blunting of immunogenicity may not be as troublesome as feared. | 1990 | 2118918 |
role of endogenous gamma interferon in host response to infection with blood-stage plasmodium chabaudi as. | the role of gamma interferon (ifn-gamma), a pluripotent lymphokine capable of activating macrophages, in acquired immunity to blood-stage malaria was investigated. c57bl-derived, lipopolysaccharide-resistant c57bl/10scn mice, which were found to be resistant to intraperitoneal (i.p.) infection with 10(6) plasmodium chabaudi as parasitized erythrocytes, were treated with monoclonal anti-ifn-gamma antibody (mab). two mabs were used: r4-6a2, a rat anti-mouse, neutralizing immunoglobulin g1, which w ... | 1990 | 2119342 |
rapid detection and sequencing of specific in vitro amplified dna sequences using solid phase methods. | we describe a rapid solid phase assay for detection and sequencing of dna sequences based on selective introduction of biotin and isotope into the specific dna fragment amplified by the polymerase chain reaction (pcr). a two-step pcr procedure is used to lower the background signal. the in vitro amplified material is immobilized on magnetic beads with covalently coupled streptavidin and the amount of bound label is measured. samples identified as positive can be analysed by direct solid phase dn ... | 1990 | 2119482 |
[vaccination against malaria: initial trial with an ant-sporozoite vaccine, (nanp)3-tt (ro 40-2361) in africa (bobo-dioulasso, burkina faso)]. | the vaccine (nanp)3-tt is a synthetic peptide of the circumsporozoite protein (cs) of plasmodium falciparum coupled to tetanus toxoid (tt) as protein carrier and adsorbed to aluminium hydroxide as adjuvant. the objectives of the study were to assess the immunogenicity and the protective efficacy of the vaccine in an area where malaria is endemic. the study was conducted in a zone of irrigated rice cultivation known as the vallée du kou to the north of bobo-dioulasso. malaria transmission is perm ... | 1990 | 2119897 |
macrophage activation in falciparum malaria as measured by neopterin and interferon-gamma. | macrophage activation during acute falciparum malaria in 71 thai adults was investigated by measuring urinary neopterin and serum interferon-gamma (ifn-gamma). neopterin, a product of ifn-gamma-activated macrophages, was elevated in 94% of patients upon admission (day 0, prior to treatment) and in all at some time during the period of study. neopterin levels tended to rise further (days 1-5) before falling back towards the normal range as patients recovered following effective chemotherapy (days ... | 1990 | 2119922 |
a single exon codes for the enzyme domain of a protozoan cysteine protease. | theileria parva is an intracellular protozoan parasite of cattle. we have determined the nucleotide sequence of a gene and cdna coding for a cysteine protease of t. parva. the gene is divided into two exons. the first exon codes for a signal sequence and for part of the "pro" region of the zymogen. the second exon codes for the remainder of the pro region, including residues thought to be involved in zymogen processing, and for the entire enzyme domain. part of this exon cross-hybridizes, at hig ... | 1990 | 2120221 |
occupational malaria in thai rangers: epidemiological, clinical and immunological features. | malaria continues to be a serious disease threat to soldiers deployed in tropical environments. distinct features of the disease and the host immune response require that malaria occurring in occupational groups be investigated separately from the infection as found in endemic populations. for the first time since the vietnam war, malaria has been systematically studied in soldiers under combat conditions. in this report we describe characteristics of malaria as experienced by thai rangers opera ... | 1990 | 2120625 |
malaria, microscopy and marmosets: the saga of tropical nephrotic syndrome. | | 1990 | 2120737 |
cell-adhesive motif in region ii of malarial circumsporozoite protein. | the segment of the malarial circumsporozoite (cs) protein designated region ii is highly conserved among different malarial species. a similar sequence is also present in several other proteins, including thrombospondin, properdin, and a blood-stage antigen of plasmodium falciparum. by means of peptides synthesized from sequences of the plasmodium vivax cs protein in the vicinity of region ii, it was found that two overlapping 18- to 20-amino acid peptides promoted the adhesion of a variety of h ... | 1990 | 2120774 |
technological advances in blood rheology. | the science of blood rheology (study of the flow and deformability of blood) is of increasing practical importance to the investigation of blood disorders. in diagnostic laboratories, rheological tests such as the erythrocyte sedimentation rate, zeta sedimentation ratio, and plasma viscosity are used to monitor patients with an acute-phase response of greater than 24 h duration. in sickle-cell anemia, new methods for measuring erythrocyte deformability can be used to investigate the pathogenesis ... | 1990 | 2121160 |
interleukin 6 production in experimental cerebral malaria: modulation by anticytokine antibodies and possible role in hypergammaglobulinemia. | the production of interleukin 6 (il-6) was studied during experimental cerebral malaria (ecm) induced by plasmodium berghei anka (pba) infection. il-6 is present in the serum of mice with ecm, the highest concentrations being observed in mice with full-blown neurological syndrome. high il-6 levels were also observed, however, in the absence of pathology in nonlethal malaria infection. these data suggest that il-6 is produced in large amounts during malaria infection, but does not play a major ro ... | 1990 | 2121890 |
in vitro biosynthesis and membrane translocation of the serine rich protein of plasmodium falciparum. | the serine-rich protein (serp) of plasmodium falciparum is found within the parasitophorous vacuole. exons 1 and 2 of the serp gene were combined to a continuous open reading frame and expressed in a cell free translation/translocation system to study translocation of the protein across membranes. the protein was found to be translocated co-translationally across canine pancreatic microsomes. this process required the presence of the signal recognition particle, and it was accompanied by cleavag ... | 1990 | 2122249 |
widespread reactivity of human sera with a variant repeat of the circumsporozoite protein of plasmodium vivax. | a panel of brazilian and indian sera was screened for reactivity with a variant strain of plasmodium vivax recently isolated in thailand. this strain has been shown to have a unique repeat region which differs from the previously described p. vivax cs proteins. a total of 21/343 human sera were found to react with a synthetic peptide representing the variant p. vivax repeat. all of the sera that reacted with the variant repeat peptide, (angagnqpg)4, also reacted with variant p. vivax sporozoites ... | 1990 | 2122747 |
immune response to plasmodium berghei sporozoite antigens. i. evaluation of murine t cell repertoire following immunization with irradiated sporozoites. | the plasmodium berghei sporozoite antigen-specific t cell repertoire was analyzed in c57bl/6 (h-2b), balb/c (h-2d) and c3h/hen (h-2k) mice following immunization with irradiated sporozoites. proliferative responses were correlated with the protective status of each strain. proliferative reactivities to sporozoite antigens were compared in cultures containing either cd4+ t cells, cd8+ t cells, or total splenic lymphocytes. cd8+ t cells had no proliferative activity to sporozoite antigens; cd4+ t ... | 1990 | 2122748 |
imported malaria associated with malariotherapy of lyme disease--new jersey. | | 1990 | 2123017 |
vector-transmitted diseases in central america, belize and panama. | | 1990 | 2124815 |
vh and vl region structure of antibodies that recognize the (nanp)3 dodecapeptide sequence in the circumsporozoite protein of plasmodium falciparum. | the sporozoite form of plasmodium falciparum displays on its surface the circumsporozoite (cs) protein. the central domain of this protein possesses a reiterated tetrapeptide sequence asn-ala-asn-pro (nanp), and greater than 90% of the sporozoite-specific antibodies obtained from individuals living in malaria endemic areas recognize epitopes within this repeat sequence. considering the highly repetitive structure of this naturally occurring antigen and its immunodominance, we were interested in ... | 1990 | 2125276 |
preparation of proteosome-based vaccines. correlation of immunogenicity with physical characteristics. | in order to facilitate the use of proteosome-based vaccines, we have identified and analyzed the parameters that affect their immunogenicity. as a model system we used synthetic peptides (lcf6) containing sequences from the immunodominant (nanp)n tandem repeat region of the p. falciparum circumsporozoite protein, hydrophobically complexed to multimeric protein preparations (proteosomes) of meningococcal outer membrane proteins (omp), since we have previously shown that high levels of anti-(nanp) ... | 1990 | 2125617 |
[cost-benefit analysis of malaria prophylaxis with mefloquine in travelers to kenya]. | with an increasing movement towards cost saving in the health sector, preventive medicine must also be judged according to its economic viability. the fact that prevention can autofinance itself is suggested by the results of a cost/benefit analysis of chemoprophylaxis of falciparum malaria with mefloquin among travellers in kenya. out of the whole group of travellers analysed by means of an interview-based test (malpro-study), the costs in the case of both switzerland and the federal german rep ... | 1990 | 2125779 |
[in vitro induction of plasmodium falciparum schizogony by human high density lipoproteins (hdl)]. | the effects of serum and human lipoproteins (hdl, vldl, ldl) were investigated on the intraerythrocytic cycle of p. falciparum using in vitro synchronized cultures. the reinvasion process of erythrocytes by merozoites and the development until the young trophozoite stage are independent of serum components. in the absence of serum, schizogony did not occur. however, addition of serum before the 24th hour of culture in basal medium restores a normal schizogony. serum replacement by the different ... | 1990 | 2125846 |
serum tumor necrosis factor associated with malaria in patients in the solomon islands. | there is now significant evidence that tumor necrosis factor (tnf) is involved in the pathogenesis of malaria. we have tested sera from patients presenting with a febrile illness admitted to hospital in honiara, solomon islands, for the presence of tnf, interferon-gamma, and interleukin-1 (il-1). this study differs from previous reports as the subjects were mainly adults from a semi-immune population living in an endemic area. the results from 2 different commercially-available assays for tnf we ... | 1990 | 2126152 |
role of interferon-gamma and tumor necrosis factor in host resistance to plasmodium chabaudi as. | the contribution of the t cell- and macrophage-derived cytokines, interferon-gamma (ifn-gamma) and tumor necrosis factor (tnf), respectively, in the cell-mediated mechanisms leading to acquired immunity to blood-stage plasmodium chabaudi as was investigated. to examine the contribution of ifn-gamma, resistant c57bl-derived mice were treated during infection with two different neutralizing, anti-murine ifn-gamma mabs. such treatment impaired the ability of the host to limit parasite multiplicatio ... | 1990 | 2126523 |
cellular mechanisms of nonspecific immunity to intracellular infection: cytokine-induced synthesis of toxic nitrogen oxides from l-arginine by macrophages and hepatocytes. | nitric oxide (no) produced by cytokine-treated macrophages and hepatocytes plays a vital role in protective host responses to infectious pathogens. no inhibits iron-sulfur-dependent enzymes involved in cellular respiration, energy production, and reproduction. synthesis of l-arginine-derived nitrite (no2-), the oxidative end product of no, directly correlates with intracellular killing of leishmania major, an obligate intracellular protozoan parasite of macrophages: the level of no2- production ... | 1990 | 2126524 |
killing of plasmodium falciparum by cytokine activated effector cells (neutrophils and macrophages). | macrophages display natural antibody independent killing of asexual blood stages of plasmodium falciparum in vitro. in contrast, the neutrophil killing of p. falciparum requires the presence of antibodies. cytokines such as tnf alpha have very little effect on the macrophage-induced antiplasmodial activity, but significantly increase the damage of parasites by neutrophils. cytokines, tnf alpha, ifn-gamma and tnf beta at very high concentrations were not toxic to p. falciparum in culture. it is p ... | 1990 | 2126525 |
anti-parasite effects of cytokines in malaria. | cytokines induced during natural malaria infections, e.g., at crisis of a blood infection of plasmodium cynomolgi, and during clinical paroxysms in human plasmodium vivax infections, mediate killing of intra-erythrocytic blood stage malaria parasites. these cytokines, tnf and ifn-gamma, require additional, yet unidentified complementary factors that are present in "crisis" and "paroxysm" serum to kill intra-erythrocytic blood stage parasites. in contrast, cytokines, (mainly ifn-gamma) are able t ... | 1990 | 2126526 |
measuring cellular immune responses to malaria antigens in endemic populations: epidemiological, parasitological and physiological factors which influence in vitro assays. | measurements of in vitro cellular immune responses to malaria antigens are influenced by a variety of external factors. the physiological status of the donor, which is affected by, for example, malaria infection, intercurrent illness and pregnancy, can influence the lymphoproliferative response to specific antigens. prior exposure to malaria antigens, determined by malaria endemicity, seasonal variations in transmission and the degree of polymorphism of the particular antigen, will also affect t ... | 1990 | 2126527 |
effects of interferon in malaria infection. | earlier, we reported that prophylactic treatment with human interferon gamma (rhuifn-gamma) protected monkeys against plasmodium cynomolgi b malaria infection. we have tested the efficacy of rhuifn-gamma on relapsing stage of experimental p. cynomolgi b malaria infection in rhesus monkeys. no effect of rhuifn-gamma was seen against experimental relapsing stage compared with controls; however, it appears that chloroquine (chl) may have interfered with the antimalarial effect of ifn, since treatme ... | 1990 | 2126528 |
cell-mediated immunity to the asexual blood stages of malarial parasites: animal models. | studies using experimental models of malaria in immunodeficient mice and chickens have shown that resistance to blood-stage infection is mediated by protective antibodies and t cell-dependent cell-mediated mechanisms of immunity. depending on the infecting species of plasmodium and prior experience of the host, either humoral or cell-mediated immune mechanisms predominate. cell-mediated immunity has been adoptively transferred with cd4+ splenic t cells, and with antigen-specific t cell lines and ... | 1990 | 2126529 |
experimental studies on combinations of pyronaridine/primaquine versus chloroquine/primaquine. | the toxicity of combined use of blood schizontocide pyronaridine (pnd) and primaquine (pq) in mice and rats was significantly lower than that of chloroquine (cq) plus primaquine (pq). pnd 1/2 ld50 (ca 600 mg/kg) in combination with pq reduced the toxic action of pq in mice, while cq 1/2 ld50 (ca 300 mg/kg) plus pq produced synergistic toxic effect. in animal models such as plasmodium yoelii sporozoite infection in mice and p. cynomolgi sporozoite infection in rhesus monkeys, the tissue schizonto ... | 1990 | 2127247 |
identification of an apically-located antigen that is conserved in sporozoan parasites. | sporozoan parasites of the phylum apicomplexa all possess common apical structures. the current study used a monoclonal antibody (mab-e12) to identify a conserved antigen in the apical region of merozoites of seven species of plasmodium (including rodent, primate and human pathogens), tachyzoites of toxoplasma gondii, bradyzoites of sarcocystis bovis, and sporozoites and merozoites of eimeria tenella and e. acervulina. the antigen was also present in sporozoites of haemosporinid parasites. immun ... | 1990 | 2128339 |
the role of cytokines in malaria infection. | we have tested the prophylactic effect of escherichia coli-derived recombinant human interferon gamma (rhuifn-(gamma] against sporozoite- or trophozoite-induced plasmodium cynomolgi b malaria infection in rhesus monkeys. data show that treatment with only five doses of rhuifn-(gamma) (0.1 mg/kg body weight) given on days -2, 0, and +2 after infection protected the monkeys against sporozoite-induced p. cynomolgi infection. animals initially protected by rhuifn-(gamma) treatment remained susceptib ... | 1990 | 2128826 |
sequence coding for a sexual stage specific protein of plasmodium falciparum. | | 1990 | 2129551 |
[borreliosis and pregnancy. (review of the literature apropos of 1 case)]. | it exists, essentially, in two, epidemiological forms: recurrent fever (fr) carried by fleas, resulting in wide scale epidemics; recurrent fever carried by ticks (soft ticks) of the ornithodorus type which results in localized, endemo-sporadic manifestations throughout the world. the second type is the main one in these regions, but the first is not uncommon. the report covers a peculiar case of flea-borne borreliosis occurring in a pregnant woman and associated with the presence of hbs antigen ... | 1990 | 2131186 |
forty years of malaria eradication in sardinia. a new appraisal of a great enterprise. | the campaign against malaria in sardinia carried out by the ente regionale per la lotta anti-anofelica in sardegna (erlaas), appears today as one of the greatest efforts against malaria since the discovery of its aetiology and mode of transmission. the disease was eradicated without achieving the eradication of the vector, anopheles labranchiae, the main objective of the campaign. this species eradication failure had been at first attributed to the indigenous character of a. labranchiae and its ... | 1990 | 2132434 |
effect of anti-mosquito antibodies on the infectivity of the rodent malaria parasite plasmodium berghei to anopheles farauti. | the effect of mouse anti-mosquito antibodies, present in the bloodmeal, on the infectivity of plasmodium berghei vincke to anopheles farauti laveran was investigated. significantly fewer oocysts developed in mosquitoes feeding on mice immunized with sugar-fed mosquito midgut antigens than in mosquitoes feeding on control mice. mosquitoes feeding on mice immunized with the midgut antigens derived from sugar-fed mosquitoes also showed reduced mortality and had lower infection rates than those fed ... | 1990 | 2132980 |
anopheles pharoensis and transmission of plasmodium falciparum in the senegal river delta, west africa. | 1. anopheles pharoensis theobald was found to be the prevalent man-biting anopheline mosquito in the central area of the senegal river delta. 2. blood-fed females of an. pharoensis were obtained during september-december 1987 from mosquito bednets in the village of souhloul, near the boundoum dam, 70 km ne of st louis. 3. dried mosquito specimens were identified morphologically and each thorax processed using monoclonal antibody against the circumsporozoite protein of plasmodium falciparum. 4. f ... | 1990 | 2133009 |
malaria transmission potential of anopheles mosquitoes in the mwea-tebere irrigation scheme, kenya. | 1. anopheles arabiensis patton and an. funestus giles were identified as vectors of plasmodium falciparum malaria in the mwea-tebere irrigation scheme, kenya. an. arabiensis was the only member of the an. gambiae complex identified from chromosome characteristics. other anopheles species found included an. pharoensis theobald, an. rufipes gough and an. coustani laveran. survival rates per gonotrophic cycle for an. arabiensis averaged 0.37 during the short rains (october-november), 0.49 during th ... | 1990 | 2133010 |
the immunodominant surface antigen of plasmodium gallinaceum is present in both the salivary gland and oocyst sporozoites. | 1. monoclonal antibodies (mabs) against surface antigens of plasmodium gallinaceum sporozoites, an avian malaria parasite, were produced using spleen cells from mice immunized with sporozoites from mosquito salivary glands (sgs) or from midguts containing oocysts (oos). 2. all of the 15 mabs tested (11 anti-sgs and 4 anti-oos) reacted with sgs and oos by indirect immunofluorescence and circumsporozoite precipitation reactions. fourteen of these mabs (11 anti-sgs and 3 anti-oos) produced a wester ... | 1990 | 2133018 |
[host-parasite interactions: mechanisms for recognition and attack]. | host-parasite interactions were studied by several researchers in these last years, both to better understand some parasite diseases and to identify new targets and strategies for the control of these infections. in this paper some of the most important recognition's mechanisms demonstrated between specific parasite structures and host cell receptors are reported, and particularly those concerning protozoa leishmania, plasmodium, entamoeba, giardia and pneumocystis. | 1990 | 2133333 |
travel-related parasitic infections. | among various kinds of tropical diseases, which tourists to tropical areas may be exposed to and return home infected with, the most important one from the korean view point is malaria. the life cycles of plasmodium falciparum and p. malariae could hardly be established even after importation, however, one cannot completely rule out a possibility of re-establishment of tertian malaria, due to p. vivax, in korea. in view of this possibility, the current malaria situation in countries of western p ... | 1990 | 2133422 |
antibody formation to low-dose antigen and plasmodium yoelii clearance by offspring of protein-depleted male and female mice. | primary and secondary immune responses to low doses of sheep red blood cells (srbc) were investigated in well-fed first-degree offspring of three groups of protein-deficient mice (pd) and in well-fed first-degree offspring of well-fed mice (nd). the offspring of malnourished males and malnourished females had the highest level of primary anti-srbc antibodies, followed by the offspring of well-fed males and malnourished females, which also had a significantly higher primary anti-srbc antibody tit ... | 1990 | 2134561 |
[the immunoenzymatic assay (elisa) in the serodiagnosis of plasmodium vivax]. | elisa was evaluated for the serodiagnosis of plasmodium vivax using homologous antigen. this was a crude fraction obtained after detergent (np-40) lysis of human parasitized red blood cells. antibodies of the classes igm, igg, iga were determined in a pool of eleven sera from patients with p. vivax malaria. the protein a was introduced as secondary probe to screen p. vivax antibodies in 30 sera of patients harbouring a first episode of p. vivax malaria. there was a correlation of 93% with the pa ... | 1990 | 2135372 |
[research on malaria vaccine]. | malaria is an important public health problem in developing countries. the production of a good vaccine needs a better knowledge of different mechanisms which control the immune system. results from donors show a higher frequency of antigens hla: a2, b35, cw4, cw6, drw52, dqw1 and dqw3. the lymphoproliferation in vitro of mononuclear cells, t cells and cd4+ and cd8+ subsets t cells with merozoite extracts is not so clear to establish a correlation between hla phenotypes and t cells response. | 1990 | 2135805 |
[the possible therapeutic effect of deferoxamine in experimental infections of mice by plasmodium berghei]. | deferoxamine is a compound with iron chelating properties. body depletion of this mineral, according to some authors, might influence the metabolism of plasmodia that thrive in the erythrocytes. in order to verify this possibility, we administered daily doses of 300 or 1.000 mg/kg of the compound, for five days and again 15 days, to mice infected with plasmodium berghei. the parameters used to check the activity of deferoxamine were mortality of the animals and the count of blood parasites. the ... | 1990 | 2135836 |
[drug resistance of plasmodium falciparum. consequences and future prospects]. | | 1990 | 2137228 |
[epidemiology of paludism. retrospective study in the paris university hospital from 1976 to 1988]. | | 1990 | 2137236 |
lack of ir gene control in the immune response to malaria. i. a thymus-independent antibody response to the repetitive surface protein of sporozoites. | the anamnestic antibody response to synthetic peptide antimalarial vaccines is under ir gene control. it has therefore been inferred that the development of antibody responses to the native repetitive ag of malaria parasites also requires linkage of t and b cell epitopes, presentation of ag in the context of mhc class ii components, and cognate t cell help for antibody production. in this study, we sought to test this assumption, by utilizing classical protocols to determine whether the antibody ... | 1990 | 2138652 |
serious adverse drug reactions to pyrimethamine-sulphadoxine, pyrimethamine-dapsone and to amodiaquine in britain. | all reports of adverse reactions with pyrimethamine-sulphadoxine (fansidar), pyrimethamine-dapsone (maloprim), and amodiaquine spontaneously reported through the uk national post-marketing system were reviewed. retrospective reporting rates of serious reactions associated with these drugs were analysed using prescription data from the department of health, derived from the prescription pricing authority, and relevant pharmaceutical companies. whilst interpretation of these data requires caution, ... | 1990 | 2138674 |
phosphofructokinase from plasmodium berghei. influence of mg2+, atp and mg2(+)-complexed atp. | the control enzyme phosphofructokinase is of regulatory significance in the metabolism of glucose by the malarial parasite plasmodium berghei. (1) the enzyme was partially purified from erythrocytic stages of p. berghei by precipitation with poly(ethylene glycol) and chromatography on 2',5'-bisphosphoadenosine-sepharose 4b. (2) similarly to various other phosphofructokinases, the enzyme from p. berghei shows an allosteric behaviour. it is activated by fructose 6-phosphate and inhibited by atp. ( ... | 1990 | 2139776 |
[clinical and therapeutic approach in plasmodium falciparum malaria in non-immune patients]. | | 1990 | 2139959 |
hypersensitive mung bean nuclease cleavage sites in plasmodium knowlesi dna. | nucleotide sequences of plasmodium knowlesi dna that are cleaved by mung bean nuclease (mbn) at low enzyme concentration (0.2 units enzyme per micrograms dna) are listed. they are tandemly repeated purine/pyrimidine (rpy) stretches of dna with (apt) dimers predominating. most cut sites are within almost 100% rpy tracts. the enzyme cleaves at many points within the rpy stretch and usually hydrolyzes the 5'-apt-3' linkage. these alternating rpy target sites are flanked by homopurine and homopyrimi ... | 1990 | 2140809 |
immunosuppression in murine malaria: suppressor role of macrophages and their products during acute and chronic plasmodium berghei infection. | marked suppression of igm, igg and iga plaque forming cells was observed in mice immunized with sheep erythocytes (t-dependent antigen) during acute plasmodium berghei infection whereas during chronic infection mild immunosuppression was observed. when mice were immunized with polyvinylpyrrolidone (t-independent antigen), suppression in the number of plaque forming cells was observed at higher parasitaemias only during acute infection whereas during chronic infection the number remained within n ... | 1990 | 2141476 |
phosphofructokinase from plasmodium berghei: a kinetic model of allosteric regulation. | as in mammalian cells, phosphofructokinase (pfk) is of major regulatory importance in the glucose metabolism of plasmodium berghei. the malarial enzyme shows allosteric properties similar to pfk from various sources; it is activated by fructose-6-phosphate and inhibited by atp, but differs with respect to allosteric regulation. enzyme activity is only marginally increased by amp, a potent activator of many phosphofructokinases. phosphoenolpyruvate, which is reported to inhibit pfk activity, effi ... | 1990 | 2141917 |
[erythrocytes infected by plasmodium falciparum activate human platelets]. | blood platelets are involved in plasmodium falciparum malaria pathology as shown by thrombocytopenia and increased plasma level of two alpha granule proteins: beta thromboglobulin (beta tg) and platelet factor 4 (pf4). in this study we demonstrate that plasmodium falciparum parasitized erythrocytes activate directly the secretion of beta tg and pf4 by human platelets. this secretion is related to parasitemia and occurs immediately after contact. treatment of parasited erythrocytes by trypsin and ... | 1990 | 2142012 |
the pathogenesis of plasmodium falciparum-associated tissue lesions--what role for c3b receptors? | human tissue sections from cerebral and cerebellar cortices, the liver, the stomach pylorus, the kidney and the placenta, were examined for the presence of c3b receptors. this was carried out in order to determine whether these receptors play any role in the pathological effects of malarial infections on these tissues. the sheep erythrocyte/rabbit antibody/complement system was used. c3b receptors were only detected in the kidney glomeruli, but not in the other tissues. it is suggested that duri ... | 1990 | 2142849 |
secondary structure and immunogenicity of hybrid synthetic peptides derived from two plasmodium falciparum pre-erythrocytic antigens. | multicomponent synthetic vaccines containing both b and t cell epitopes belonging to two different pre-erythrocytic ag of plasmodium falciparum are presented. in a di-component hybrid, a circumsporozoite t cell epitope and a peptide representing a liver stage-specific ag were connected to obtain a reciprocal reinforcement of helical potentials. in a tri-component hybrid, a sequence corresponding to the circumsporozoite repeat tetrapeptide (npna) was tandemly synthesized on the n-terminal end of ... | 1990 | 2143519 |
the adoptive transfer of t-cell dependent immunity to plasmodium chabaudi chabaudi in cba/ca mice is achieved only after superinfection of immune spleen cell donors. | the transfer of spleen cells from cba/ca mice recovered from a p. c. chabaudi as primary infection into irradiated syngeneic recipients conferred very poor protection. neither elimination of ly2 cells from immune spleen cells nor reinfection of the donors some days before transfer improved protection significantly. significant protection was transferred with spleen cells from donors which had been infected 7 times prior to cell transfer. transferred protection was reduced or eliminated by pretre ... | 1990 | 2143571 |
regulation of the energy metabolism of plasmodium berghei. | energy metabolism of malaria parasites was investigated in p. berghei infected red blood cells of rat. although plasmodia contain mitochondria most of their atp is formed by glycolysis. lactate formation is two orders of magnitude higher than in noninfected erythrocytes. the coupling of respiration and glycolysis is very loose, a pasteur-effect was not found. the key enzymes of glycolysis hexokinase and phosphofructokinase have been partially purified and kinetically characterized. the kinetic p ... | 1990 | 2143651 |
[resistance of plasmodium falciparum to mefloquine in sierra leone and kenya]. | | 1990 | 2143829 |
malaria in displaced persons along the thai-burmese border. | malaria epidemiology in displaced karen ethnic children along the thai-burmese (myanmar) border was observed for 3 years. an active screening process in connection with malaria chemoprophylaxis trials showed a decrease in malaria prevalence over time in children not receiving chemoprophylaxis. the number of malaria cases detected at a primary health care clinic in the same area remained stable. | 1990 | 2144910 |
mitogenic activity of soluble preparations from plasmodium berghei-infected erythrocytes to l3t4+, lyt2- and l3t4-, lyt2+ t-cell subsets. | the mitogenic activity of soluble preparations of plasmodium berghei-infected erythrocytes (pbep) in cultures of t or non-t cells isolated from spleens of naive mice was investigated. the proportion of cells at each phase in the cell cycle was examined by flow cytometry after incubation with various concentrations of pbep; the proliferation index (pi-cell numbers at s, g2 and m phases/cell numbers at all phases x 100) was calculated. an addition of pbep led to significant increases in the pi lev ... | 1990 | 2144965 |
changes in hemopoietic and regulator levels in mice during fatal or nonfatal malarial infections. i. erythropoietic populations. | erythroid precursors bfu-e and cfu-e and erythroblasts (erb) were monitored in the marrow and spleen of mice during fatal or nonfatal malaria. transient depletions of marrow cfu-e and erb without modification of bfu-e or erythropoietin (epo) levels were found as early events in fatal infections. before anemia development, erythropoiesis was reduced in the bone marrow but increased in the spleen. during the anemic phase, for comparable levels of anemia, plasma epo levels were elevated to a simila ... | 1990 | 2146141 |
quantitative estimation of suppressor/cytotoxic and helper t cells during acute and chronic plasmodium berghei infection. | in the present study, the percentage of lymphocyte subpopulations and their relation to t cell subsets was estimated during acute and chronic plasmodium berghei malaria. during acute infection, a decreased percentage of t lymphocytes was observed, whereas no change was observed during chronic infection. however, no change in the percentage of b cells was observed in both types of infection. the t cell population was characterized by an increased percentage of t suppressor cytotoxic (cd8+) cells ... | 1990 | 2146216 |
cd4+ cytolytic t cell clone confers protection against murine malaria. | a cd4+ t cell clone (a1.6) was derived from spleen cells of mice immunized with irradiated sporozoites. this t cell clone recognizes an antigen that is shared by sporozoites and blood forms of plasmodium berghei and differs from the circumsporozoite protein. clone a1.6 displays cytotoxic activity, produces ifn-gamma and il-2 in vitro, and recognizes the plasmodial antigen in the context of the class ii i-ed molecule. passive transfer of this cd4+ clone into naive mice resulted in a high degree o ... | 1990 | 2146361 |
[the prevention of malaria by ecologically safe methods]. | 120 imported cases of malaria and 2 cases of malaria among the native population (1986-1987) likely infected by parasite carriers were registered over a period from 1970 to 1988 in georgia. the attention has been focused on the planning of preventive measures. parasitological service of the sanitary epidemiological stations is being improved. population of anophelogenic reservoirs with the larvae-eating fish gambusia (brought from italy by n. p. rukhadze in 1925) seems to be of great importance. ... | 1990 | 2146472 |
[malaria after a stay in guadeloupe]. | | 1990 | 2146657 |
[failure of chemoprevention with mefloquine in western africa]. | | 1990 | 2146671 |
[a case of plasmodium falciparum malaria contracted in guinea-bissau during chemoprophylaxis with chloroquine]. | | 1990 | 2147276 |