| recombinant plasmodium falciparum nadp-dependent isocitrate dehydrogenase is active and harbours a unique 26 amino acid tail. | during infection, plasmodium spp. require reducing equivalents such as nadph to support the function of specific enzymes in overcoming oxidative stress. the catalysis of isocitrate by the nadp-dependent isocitrate dehydrogenase of plasmodium falciparum (pficdh) generates nadph and is thus crucial for the parasite's survival and pathogenecity. in this study, pficdh was cloned from a clinical isolate of p. falciparum. this was facilitated by designing primers based on the p. falciparum genome sequ ... | 2003 | 12880588 |
| estimation of malaria transmission from humans to mosquitoes in two neighbouring villages in south cameroon: evaluation and comparison of several indices. | malaria transmission from humans to mosquitoes was assessed in two neighbouring villages in a rural area near yaoundé, cameroon during high and low transmission seasons during 1998-2000, using several indices previously evaluated in different areas endemic for malaria but never directly compared. these indices were estimated from human parasitological data and mosquito infection rates and, for each individual, thick blood films were prepared at the same time as experimental infection of laborato ... | 2003 | 12886806 |
| discovery of gene function by expression profiling of the malaria parasite life cycle. | the completion of the genome sequence for plasmodium falciparum, the species responsible for most malaria human deaths, has the potential to reveal hundreds of new drug targets and proteins involved in pathogenesis. however, only approximately 35% of the genes code for proteins with an identifiable function. the absence of routine genetic tools for studying plasmodium parasites suggests that this number is unlikely to change quickly if conventional serial methods are used to characterize encoded ... | 2003 | 12893887 |
| structure, evolution, and inhibitor interaction of s-adenosyl-l-homocysteine hydrolase from plasmodium falciparum. | s-adenosylhomocysteine hydrolase (sahh) is a key regulator of s-adenosylmethionine-dependent methylation reactions and an interesting pharmacologic target. we cloned the sahh gene from plasmodium falciparum (pfsahh), with an amino acid sequence agreeing with that of the plasmodb genomic database. even though the expressed recombinant enzyme, pfsahh, could use 3-deaza-adenosine (dza) as an alternative substrate in contrast to the human sahh, it has a unique inability to substitute 3-deaza-(+/-)ar ... | 2003 | 12910461 |
| oxindole-based compounds are selective inhibitors of plasmodium falciparum cyclin dependent protein kinases. | cyclin dependent protein kinases (cdks) have become attractive drug targets in an effort to identify effective inhibitors of the parasite plasmodium falciparum, the causative agent of the most severe form of human malaria. we tested known cdk inhibitors for their ability to inhibit two malarial cdks: pfmrk and pfpk5. many broad spectrum cdk inhibitors failed to inhibit pfmrk suggesting that the active site differs from other cdks in important ways. by screening compounds in the walter reed chemi ... | 2003 | 12930149 |
| drug targets in malaria parasites. | malaria ranks with tuberculosis and aids in terms of its ability to destroy human health. in india there are at least two million cases seen annually. although mortality may not be as high as it is in africa, the trauma due to morbidity and debility and loss of productive man hours are colossal. since resistance to chloroquine and antifolates is spreading rapidly, there is need to develop new pharmacophores, for which identification of new drug targets is essential. this review focuses on target ... | 2003 | 12934935 |
| modulation of whole-cell currents in plasmodium falciparum-infected human red blood cells by holding potential and serum. | recent electrophysiological studies have identified novel ion channel activity in the host plasma membrane of plasmodium falciparum-infected human red blood cells (rbcs). however, conflicting data have been published with regard to the characteristics of induced channel activity measured in the whole-cell configuration of the patch-clamp technique. in an effort to establish the reasons for these discrepancies, we demonstrate here two factors that have been found to modulate whole-cell recordings ... | 2003 | 12937282 |
| plasmodium falciparum adhesion in the placenta. | plasmodium falciparum parasites sequester in the human placenta, and placental malaria is associated with disease and death of both mother and child. placental isolates of p. falciparum uniformly bind to chondroitin sulfate a on the syncytiotrophoblast. forms of the variant surface antigen pfemp1 that bind chondroitin sulfate a in vitro (pfemp1(varcsa)) are highly conserved in many field isolates. two related forms of pfemp1(varcsa) are commonly expressed by placental isolates, but these are als ... | 2003 | 12941407 |
| infectious aetiology of jaundice among pregnant women in angola. | the contribution of viral hepatitis, human immunodeficiency virus (hiv) infection and malaria to jaundice among pregnant women in luanda, angola, was studied. 20 pregnant women with jaundice (cases) were identified in 2 large maternity hospitals and compared with 40 pregnant women without jaundice (controls). among the cases 6 patients died, whereas no death occurred in the control group (p < 0.001). five spontaneous abortions and 6 stillbirths were also noted among the cases, implying foetal lo ... | 2003 | 12953953 |
| crystal structure of plasmodium berghei lactate dehydrogenase indicates the unique structural differences of these enzymes are shared across the plasmodium genus. | as plasmodium rely extensively on homolactic fermentation for energy production, plasmodium falciparum lactate dehydrogenase (pfldh)--the key enzyme in this process--has previously been suggested as a novel target for antimalarials. this enzyme has distinctive kinetic and structural properties that distinguish it from its human homologues. in this study, we now describe the expression, kinetic characterisation and crystal structure determination of the ldh from plasmodium berghei. this enzyme is ... | 2003 | 12967707 |
| plasmodium falciparum eba-140 kda protein peptides that bind to human red blood cells. | the erythrocyte-binding antigen 140 (eba140) sequence was chemically synthesized in 61 20-mer sequential peptides covering the entire 3d7 protein strain, each of which was tested in erythrocyte-binding assays. peptides 26135, 26144, 26147, 26160, 26170 and 26177 presented high erythrocyte-binding activity, with affinity constants ranging from 350 to 750 nm. critical erythrocyte-binding residues were determined by competition-binding assays with glycine analogous peptides. cross-linking assays wi ... | 2003 | 12969197 |
| studies on the nature of malarial pigment (haemozoin). ii. the pigment of the human species, plasmodium falciparum and p. malariae. | | 1956 | 13340682 |
| experiments with antimalarial drugs in man. vii. the suppressive effect of 50 mg. of chloroquine base daily in british troops exposed to infection with plasmodium falciparum. | | 1957 | 13496183 |
| rationale and plans for developing a non-replicating, metabolically active, radiation-attenuated plasmodium falciparum sporozoite vaccine. | annually, malaria causes >300 million clinical cases and 1 million deaths, is responsible for the loss of >1% of gross domestic product (gdp) in africa and is a serious concern for travelers. an effective vaccine could have a dramatic impact on the disease. for 20 years, scientists have tried to develop modern, recombinant 'subunit' malaria vaccines. this has been difficult. in fact, there is only one recombinant protein vaccine on the market for any disease, and no vaccines based on synthetic p ... | 2003 | 14506215 |
| the methylerythritol phosphate pathway and its significance as a novel drug target. | isopentenyl diphosphate (ipp) and dimethylallyl diphosphate (dmapp) are the precursors for all isoprenoid compounds. two pathways are found in nature for their biosynthesis. the mevalonate (mva) pathway is found in eukaryotes, algae, archae and some gram-positive bacteria. gram-negative bacteria, plants and some gram-positive bacteria utilize the methyl erythritol phosphate (mep) pathway. the distribution and the orthogonal nature of the pathways make the mep pathway an attractive new target for ... | 2003 | 14529427 |
| synthesis and evaluation of novel 7-trifluoromethyl-4-(4-substituted anilino)quinolines as antiparasitic and antineoplastic agents. | several novel derivatives bearing the 7-trifluoromethyl-4-(4-substituted anilino)-quinoline skeleton were synthesized and evaluated for their in vitro activity against the blood streaming form of the parasites trypanosoma brucei rhodesiense, the trypomastigotes of trypanosoma cruzi cultured in rat skeletal myoblasts, the amastigotes form of leishmania donovani, plasmodium falciparum (k1 strain) infected erythrocyte suspension, as well as their toxicity towards rat skeletal l-6 cells. in addition ... | 2003 | 14558440 |
| effect of plasmodium falciparum parasitaemia on some haematological parameters in adolescent and adult nigerian hbaa and hbas blood genotypes. | to compare the susceptibility of hbaa and hbas blood genotypes to plasmodium falciparum in human subjects. | 2002 | 14562598 |
| maurer's clefts--a novel secretory organelle? | during intra-erythrocytic development, the human malarial parasite plasmodium falciparum extensively remodels its adopted cellular home by exporting proteins beyond the confines of its own plasma membrane, but is, however, faced with a major problem: the lack of an endogenous protein trafficking machinery within the host erythrocyte. thus, in order to export proteins the parasite has to install its own protein export system within the host erythrocyte. a growing body of evidence suggests that ma ... | 2003 | 14563533 |
| extracellular lysines on the plasmodial surface anion channel involved in na+ exclusion. | the human malaria parasite, plasmodium falciparum, induces an unusual ion channel, the plasmodial surface anion channel (psac), on its host red blood cell (rbc) membrane. psac has a broad selectivity with permeability to anions, sugars, amino acids, purines, and certain vitamins, suggesting a role in nutrient acquisition by the intracellular parasite. permeating solutes cover a range of molecular sizes and may be either neutral or carry a net negative or positive charge. despite this broad selec ... | 2003 | 14563534 |
| analysis of sepik populations of papua new guinea suggests an increase of cyp2c19 null allele frequencies during the colonization of melanesia. | the cytochrome p450 (cyp) isozyme cyp2c19 metabolizes clinically important drugs, including the anti-malarial proguanil currently used for multi-drug resistant plasmodium falciparum malaria. cyp2c19 activity varies among geographical regions due to high frequencies of two null alleles (cyp2c19*2/*3) in asian and especially pacific populations. previously, we reported an unprecedentedly high frequency of cyp2c19 poor metabolizers (pm) within populations of vanuatu, which suggested even higher pm ... | 2003 | 14583683 |
| integrative analysis of intraerythrocytic differentially expressed transcripts yields novel insights into the biology of plasmodium falciparum. | background: the intraerythrocytic development of plasmodium falciparum, the most virulent human malaria parasite involves asexual and gametocyte stages. there has been a significant increase in disparate datasets derived from genomic and post-genomic analysis of the parasite that necessitates delivery of integrated analysis from which biological processes important to the survival of the parasite can be determined. methods: in order to resolve genes associated with stage differentially expressed ... | 2003 | 14617379 |
| strand compositional asymmetries of nuclear dna in eukaryotes. | both dna replication and transcription are structurally asymmetric processes. an asymmetric nucleotide substitution pattern has been observed between the leading and the lagging strand, and between the coding and the noncoding strand, in eubacterial, viral, and organelle genomes. similar studies in eukaryotes have been rare, because the origins of replication in nuclear genomes are mostly unknown and the replicons are much shorter than those of prokaryotes. to circumvent these predicaments, all ... | 2003 | 14629042 |
| dependence of plasmodium falciparum in vitro growth on the cation permeability of the human host erythrocyte. | intraerythrocyte growth of the malaria parasite plasmodium falciparum induces a ca2+-permeable unselective cation conductance in the host cell membrane which is inhibited by ethylisopropylamiloride (eipa) and is paralleled by an exchange of k+ by na+ in the host cytosol. the present study has been performed to elucidate the functional significance of the electrolyte exchange. whole-cell patch-clamp experiments confirmed the ca2+ permeability and eipa sensitivity of the plasmodium falciparum indu ... | 2003 | 14631141 |
| 5ht1a serotonin receptor agonists inhibit plasmodium falciparum by blocking a membrane channel. | to identify new leads for the treatment of plasmodium falciparum malaria, we screened a panel of serotonin (5-hydroxytryptamine [5ht]) receptor agonists and antagonists and determined their effects on parasite growth. the 5ht1a receptor agonists 8-hydroxy-n-(di-n-propyl)-aminotetralin (8-oh-dpat), 2,5-dimethoxy-4-iodoamphetamine, and 2,5-dimethoxy-4-bromophenylethylamine inhibited the growth of p. falciparum in vitro (50% inhibitory concentrations, 0.4, 0.7, and 1.5 microm, respectively). in fur ... | 2003 | 14638487 |
| biochemical and immunological characterization of bacterially expressed and refolded plasmodium falciparum 42-kilodalton c-terminal merozoite surface protein 1. | protection against plasmodium falciparum can be induced by vaccination in animal models with merozoite surface protein 1 (msp1), which makes this protein an attractive vaccine candidate for malaria. in an attempt to produce a product that is easily scaleable and inexpensive, we expressed the c-terminal 42 kda of msp1 (msp1(42)) in escherichia coli, refolded the protein to its native form from insoluble inclusion bodies, and tested its ability to elicit antibodies with in vitro and in vivo activi ... | 2003 | 14638762 |
| a 24-bp duplication in exon 10 of human chitotriosidase gene from the sub-saharan to the mediterranean area: role of parasitic diseases and environmental conditions. | human chitotriosidase (chit) is a member of the chitinase family and it is synthesized by activated macrophages. recently, a genetic polymorphism was found to be responsible for the common deficiency in chit activity, frequently encountered in different populations. we analyzed the chit gene in some ethnic groups from the mediterranean and african areas, to evaluate whether the chit gene polymorphism correlates with the changes in environmental features and the disappearance of parasitic disease ... | 2003 | 14647197 |
| naturally acquired antibody responses to the components of the plasmodium falciparum merozoite surface protein 1 complex. | merozoite surface protein 6 (msp6) and 7 (msp7) of plasmodium falciparum are peripheral membrane proteins whose cleaved products, msp636, msp722 and msp719, are found on the merozoite surface as components of a non-covalently bound complex which also contains four polypeptides derived from merozoite surface protein 1 (msp1). we have expressed both the precursor regions and the processed mature products of msp6 and msp7 in escherichia coli and showed that these recombinant proteins react with hum ... | 2003 | 14651587 |
| natural killer (nk) cell-mediated cytolysis of plasmodium falciparum-infected human red blood cells in vitro. | the ability of human nk cells to inhibit the growth in vitro of the asexual blood stages of plasmodium falciparum was tested. purified nk cells from donors with no prior exposure to malaria significantly inhibited parasite growth after 48 hours of co-culture in the presence of human immune serum. this inhibition was completely abrogated by pre-treatment of the nk cells with an anti-cd95 (anti-fas) monoclonal antibody and human fas-fc soluble protein. the level of growth inhibition was also subst ... | 2003 | 14656686 |
| development of an immunohistochemical assay for the detection of babesiosis in formalin-fixed, paraffin-embedded tissue samples. | the hemoparasite babesia can cause life-threatening infections to neonates, elderly and immunocompromised people, and people who have undergone splenectomy. by using pooled hamster serum samples collected 21 days after infection with babesia microti, we developed an immunohistochemical assay for formalin-fixed, paraffin-embedded tissue (ffpet) samples and blood smears. by use of the immunohistochemical assay, parasites were detected inside erythrocytes present in the heart, spleen, and liver of ... | 2003 | 14671971 |
| childhood malaria in a region of unstable transmission and high human immunodeficiency virus prevalence. | malaria and hiv are important pediatric problems in sub-saharan africa. it is uncertain how hiv-related immunosuppression and malaria interact in children. we aimed to describe associations among hiv status, presentation and outcome from malaria in children from hlabisa district, kwazulu-natal, south africa, a region of high hiv prevalence and unstable plasmodium falciparum transmission. | 2003 | 14688565 |
| a human complement receptor 1 polymorphism that reduces plasmodium falciparum rosetting confers protection against severe malaria. | parasitized red blood cells (rbcs) from children suffering from severe malaria often adhere to complement receptor 1 (cr1) on uninfected rbcs to form clumps of cells known as "rosettes." despite a well documented association between rosetting and severe malaria, it is controversial whether rosetting is a cause or a correlate of parasite virulence. cr1-deficient rbc show greatly reduced rosetting; therefore, we hypothesized that, if rosetting is a direct cause of malaria pathology, cr1-deficient ... | 2004 | 14694201 |
| glycophorin c (gerbich antigen blood group) and band 3 polymorphisms in two malaria holoendemic regions of papua new guinea. | the geographic overlap between the prevalence of erythrocyte polymorphisms and malaria endemicity is thought to be an example of natural selection on human populations. in papua new guinea (png), the gerbich-negative phenotype is caused by an exon 3 deletion in the glycophorin c gene (gypcdeltaex3) while heterozygosity for a 27-base pair deletion in the slc4a1 gene (anion exchanger 1 or erythrocyte membrane protein, band 3), slc4a1delta27, results in southeast asian ovalocytosis. two geographica ... | 2004 | 14695625 |
| effects of bisphosphonates on the growth of entamoeba histolytica and plasmodium species in vitro and in vivo. | the effects of a series of 102 bisphosphonates on the inhibition of growth of entamoeba histolytica and plasmodium falciparum in vitro have been determined, and selected compounds were further investigated for their in vivo activity. forty-seven compounds tested were active (ic(50) < 200 microm) versus e. histolytica growth in vitro. the most active compounds (ic(50) approximately 4-9 microm) were nitrogen-containing bisphosphonates with relatively large aromatic side chains. simple n-alkyl-1-hy ... | 2004 | 14695831 |
| expression & immunogenicity of malaria merozoite peptides displayed on the small coat protein of chimaeric cowpea mosaic virus. | foreign peptide sequences can be inserted into the betab-betac loop of the cowpea mosaic virus (cpmv) small coat protein (scp) to yield functional chimaeric viruses. immunisation with chimaeric cpmv elicits immune responses that protect against human immunodeficiency and mink enteritis viruses. the present study was undertaken to investigate the expression of a b cell epitope from the merozoite surface antigen-1 of the malaria parasite plasmodium falciparum (pfmsp1) in cpmv for an epitope based ... | 2003 | 14700344 |
| [plasmodium falciparum: epidemiology and man-mosquito transmission and infection in the vector]. | the level of malaria transmission is usually estimated by some entomological parameters (entomological inoculation rate or reproductive rate and its seasonal variations). however, only one aspect of the malaria transmission is explored by this way, i.e. the transmission of plasmodium from mosquito to man. the transmission from man to mosquito, the development of parasite in the mosquito midgut, and the role of transmission blocking immunity remain poorly documented. recent studies on vaccination ... | 2003 | 14717055 |
| olfaction: mosquito receptor for human-sweat odorant. | female anopheles mosquitoes, the world's most important vector of plasmodium falciparum malaria, locate their human hosts primarily through olfactory cues, but the molecular mechanisms that underlie this recognition are a mystery. here we show that the anopheles gambiae protein agor1, a female-specific member of a family of putative odorant receptors, responds to a component of human sweat. compounds designed to activate or block receptors of this type could function as attractants for trapping ... | 2004 | 14724626 |
| the hexose transporter of plasmodium falciparum is a worthy drug target. | despite substantial efforts at control over several decades, malaria is still a major global health problem as chemotherapy of malaria parasites is limited by established drug resistance and lack of novel treatment options. intraerythrocytic stages of these parasites are wholly dependent upon host glucose for energy and malarial proteins involved in hexose permeation are therefore attractive new drug targets. for plasmodium falciparum, the causative agent of severe malaria, a facilitative hexose ... | 2004 | 14744563 |
| in vitro antiplasmodial activities of semisynthetic n,n'-spacer-linked oligomeric ergolines. | starting from three monomeric ergolines (terguride 1, festuclavine 2, pergolide 3) n,n'-spacer-linked oligomeric derivatives were prepared using different aliphatic or arylalkyl spacers. the compounds have been evaluated for their in vitro antiplasmodial activity against the chloroquine-sensitive strain pow and the chloroquine-resistant clone dd2 of plasmodium falciparum. additionally, the cytotoxic effects against mouse fibroblasts (nih 3t3) in vitro, and human hepatocytes were evaluated. all m ... | 2004 | 14759742 |
| divergent binding sites on intercellular adhesion molecule-1 (icam-1) for variant plasmodium falciparum isolates. | adhesion of human erythrocytes infected with the malaria parasite plasmodium falciparum to host endothelium has been associated with severe forms of this disease. a number of endothelial receptors have been identified, and there is evidence that one of these, intercellular adhesion molecule-1 (icam-1), may play an important role in the pathology of cerebral malaria. mutagenesis of domain 1 of icam-1, which is involved in parasite adhesion, shows that the binding sites for different parasite vari ... | 2004 | 14763979 |
| thioredoxin reductase and glutathione synthesis in plasmodium falciparum. | the malaria parasite plasmodium falciparum is still a major threat to human health in the non-industrialised world mainly due to the increasing incidence of drug resistance. therefore, there is an urgent need to identify and validate new potential drug targets in the parasite's metabolism that are suitable for the design of new anti-malarial drugs. it is known that infection with p. falciparum leads to increased oxidative stress in red blood cells, implying that the parasite requires efficient a ... | 2003 | 14962359 |
| glutathione is involved in the antimalarial action of chloroquine and its modulation affects drug sensitivity of human and murine species of plasmodium. | ferriprotoporphyrin ix (fp) is released inside the food vacuole of the malaria parasite during the digestion of host cell hemoglobin. fp is detoxified by its biomineralization to hemozoin. this process is effectively inhibited by chloroquine (cq) and amodiaquine (aq). undegraded fp accumulates in the membrane fraction and inhibits enzymes of infected cells in parallel with parasite killing. fp is demonstrably degraded by reduced glutathione (gsh) in a radical-mediated mechanism. this degradation ... | 2003 | 14962364 |
| plasmodium falciparum purine nucleoside phosphorylase: crystal structures, immucillin inhibitors, and dual catalytic function. | purine nucleoside phosphorylase from plasmodium falciparum (pfpnp) is an anti-malarial target based on the activity of immucillins. the crystal structure of pfpnp.immucillin-h (immh).so(4) reveals a homohexamer with immh and so(4) bound at each catalytic site. a solvent-filled cavity close to the 5'-hydroxyl group of immh suggested that pfpnp can accept additional functional groups at the 5'-carbon. assays established 5'-methylthioinosine (mti) as a substrate for pfpnp. mti is not found in human ... | 2004 | 14982926 |
| new 1,2,3,4-tetrahydropyrrolo[1,2-a]pyrimidinium alkaloids (phloeodictynes) from the new caledonian shallow-water haplosclerid sponge oceanapia fistulosa. structural elucidation from mainly lc-tandem-ms-soft-ionization techniques and discovery of antiplasmodial activity. | we report here on new 6-hydroxy-1,2,3,4-tetrahydropyrrolo[1,2-a]pyrimidinium alkaloids, belonging to the phloeodictyne family, isolated from the haplosclerid sponge oceanapia[=phloeodictyon]fistulosa(bowerbank, 1873) from new caledonian shallow waters. online lc-esi-ms analysis, coupled to tandem fragmentation experiments on the crude alkaloid mixture, allowed us to clarify their flat structures, including structural isomers. at least 25 different components, of which 17 are new members with var ... | 2004 | 14985819 |
| the scavenger receptor cysteine-rich (srcr) domain: an ancient and highly conserved protein module of the innate immune system. | the scavenger receptor cysteine-rich (srcr) domain is an ancient and highly conserved protein module of ~100-110 amino acids, which defines a superfamily (srcr-sf) of either soluble or membrane-bound receptors expressed by hematopoietic and nonhematopoietic cells, at either embryonic or adult stages. the existence of two types of srcr domains allows the division of the srcr-sf into two groups. members of group a contain srcr domains with 6 cysteine residues and are encoded by two exons, whereas ... | 2004 | 14995912 |
| changing scenario of malaria in central india, the replacement of plasmodium vivax by plasmodium falciparum (1986-2000). | since 1986, we have been studying the changing epidemiology of malaria in a forest belt of mandla, which has the highest number of malaria cases in central india (madhya pradesh) to define the epidemiological characteristics of the infection with each plasmodium species in different seasons of the year. our long-term objective was to determine the dynamics of plasmodium vivax vs.p. falciparum infections. | 2004 | 14996366 |
| progress with new malaria vaccines. | malaria is a parasitic disease of major global health significance that causes an estimated 2.7 million deaths each year. in this review we describe the burden of malaria and discuss the complicated life cycle of plasmodium falciparum, the parasite responsible for most of the deaths from the disease, before reviewing the evidence that suggests that a malaria vaccine is an attainable goal. significant advances have recently been made in vaccine science, and we review new vaccine technologies and ... | 2004 | 14997243 |
| identification of a rare point mutation at c-terminus of merozoite surface antigen-1 gene of plasmodium falciparum in eastern indian isolates. | merozoite surface antigen-1 (msa-1) of plasmodium falciparum is highly immunogenic in human. several studies suggest that msa-1 protein is an effective target for a protective immune response. attempt has been made to find new point mutations by analyzing 244 bp [codon 1655(r) to 1735 (i)] relatively conserved c-terminus region of msa-1 gene in 125 isolates. this region contains two egf like domains, which are involved in generating protective immune response in human. point mutations in this re ... | 2004 | 15013788 |
| infectivity of plasmodium falciparum gametocytes in patients attending rural health centres in western kenya. | experimentally studying the transmission of the malaria parasite and its regulating factors requires availability of human blood donors carrying infectious gametocytes. the difficulty of identifying gametocyte carriers from the community is often limited due to financial and human resources constraints. the available alternative is rural health centres where malaria patients go for treatment. in this study, the potential of recruiting volunteers and acquiring infectious blood for experimental in ... | 2003 | 15018419 |
| plasmodium falciparum glycogen synthase kinase-3: molecular model, expression, intracellular localisation and selective inhibitors. | worldwide increasing resistance of plasmodium falciparum to common anti-malaria agents calls for the urgent identification of new drugs. glycogen synthase kinase-3 (gsk-3) represents a potential screening target for the identification of such new compounds. we have cloned pfgsk-3, the p. falciparum gene homologue of gsk-3 beta. it encodes a 452-amino-acid, 53-kda protein with an unusual n-terminal extension but a well-conserved catalytic domain. a pfgsk-3 tridimensional homology model was genera ... | 2004 | 15023360 |
| proteomic approaches to studying drug targets and resistance in plasmodium. | ever increasing drug resistance by plasmodium falciparum, the most virulent of human malaria parasites, is creating new challenges in malaria chemotherapy. the entire genome sequences of p. falciparum and the rodent malaria parasite, p. yoelii yoelii are now available. extensive genome sequence data from other plasmodium species including another important human malaria parasite, p. vivax are also available. powerful research techniques coupled to genomic resources are needed to help identify ne ... | 2004 | 15032633 |
| targeting ion channels of plasmodium falciparum-infected human erythrocytes for antimalarial development. | aside from its profound clinical importance, the human malaria parasite, p. falciparum, is intrinsically fascinating to the cell biologist because it resides within the mature red blood cell (rbc). because the inert rbc cannot otherwise provide sufficient amounts of key substrates to fuel the vigorous parasite metabolism, the parasite must have specialized adaptations for getting these solutes into the rbc and scavenging them from rbc cytosol. two unusual ion channels have recently been identifi ... | 2004 | 15032636 |
| anti-plasmodium properties of group ia, ib, iia and iii secreted phospholipases a2 are serum-dependent. | antibacterial, antiparasitidal and antiviral properties have recently been attributed to members of the secreted phospholipases a(2) (spla(2)s) superfamily. seven spla(2)s from groups ia, ib, iia and iii, were tested here in different culture conditions for inhibition of the in vitro intraerythrocytic development of plasmodium falciparum, the causative agent of the most severe form of human malaria. in the presence of human serum, all spla(2)s were inhibitory, with three out of seven exhibiting ... | 2004 | 15033330 |
| apoptosis induced by the alkaloid sampangine in hl-60 leukemia cells: correlation between the effects on the cell cycle progression and changes of mitochondrial potential. | sampangine, a plant-derived copyrine alkaloid extracted from the stem bark of cananga odorata, primarily exhibits antifungal and antimycobacterial activities, but it also displays in vitro antimalarial activity against plasmodium falciparum and is cytotoxic to human malignant melanoma cells. it inhibits cell aggregation, but no molecular target has yet been identified. we investigated the biochemical pathway involved in sampangine-induced cytotoxicity toward hl-60 cells. these leukemia cells are ... | 2003 | 15033745 |
| a cd4(+) t-cell immune response to a conserved epitope in the circumsporozoite protein correlates with protection from natural plasmodium falciparum infection and disease. | many human t-cell responses specific for epitopes in plasmodium falciparum have been described, but none has yet been shown to be predictive of protection against natural malaria infection. here we report a peptide-specific t-cell assay that is strongly associated with protection of humans in the gambia, west africa, from both malaria infection and disease. the assay detects interferon-gamma-secreting cd4(+) t cells specific for a conserved sequence from the circumsporozoite protein, which binds ... | 2004 | 15034567 |
| structural characterization of the bovine tracheal chondroitin sulfate chains and binding of plasmodium falciparum-infected erythrocytes. | sequestration of plasmodium falciparum-infected red blood cells (irbcs) in the human placenta is mediated by chondroitin 4-sulfate (c4s). a cytoadherence assay using chondroitin sulfate proteoglycans (cspgs) is widely used for studying c4s-irbc interactions. bovine tracheal chondroitin sulfate a (csa) preparation lacking a major portion of core protein has been frequently used for the assay. here the cspg purified from bovine trachea and csa were assessed for irbc binding and the cs chains studi ... | 2004 | 15044390 |
| allelic polymorphisms in apical membrane antigen-1 are responsible for evasion of antibody-mediated inhibition in plasmodium falciparum. | apical membrane antigen-1 (ama-1) is a target of antibodies that inhibit invasion of plasmodium falciparum into human erythrocytes and is a candidate for inclusion in a malaria vaccine. we have identified a line of p. falciparum (w2mef) less susceptible to anti-ama1 antibodies raised to the protein from a heterologous parasite line (3d7). we have constructed transgenic p. falciparum expressing heterologous ama-1 alleles. in vitro invasion assays show that these transgenic parasites differ from p ... | 2004 | 15049818 |
| organic osmolyte permeabilities of the malaria-induced anion conductances in human erythrocytes. | infection of human erythrocytes with the malaria parasite plasmodium falciparum induces new permeability pathways (npps) in the host cell membrane. isotopic flux measurements demonstrated that the npp are permeable to a wide variety of molecules, thus allowing uptake of nutrients and release of waste products. recent patch-clamp recordings demonstrated the infection-induced up-regulation of an inwardly and an outwardly rectifying cl(-) conductance. the present experiments have been performed to ... | 2004 | 15051807 |
| malaria vectors in the bioko island (equatorial guinea): estimation of vector dynamics and transmission intensities. | the current study was performed on the bioko island (equatorial guinea) with the aim of establishing a rapid assessment technique for mapping malaria risk and measuring vector densities. human bait collection, tent traps, light traps, indoor resting collection, and window exit traps were used to collect anopheles gambiae s.s. and anopheles funestus, the two anopheline species involved in malaria transmission in this island. capture data were used to compare differences in the behavior and vector ... | 2004 | 15061273 |
| malaria and the red blood cell membrane. | malaria is the most serious and widespread parasitic disease of humans and is arguably the commonest disease of red blood cells (rbcs). malaria has exerted a powerful effect on human evolution and selection for resistance has led to the appearance and persistence of a number of inherited diseases. after parasite invasion, rbcs are progressively and dramatically modified. new structures appear inside the rbc and novel parasite proteins are exported to the erythrocyte cytoplasm and membrane skelet ... | 2004 | 15071793 |
| plasmodium falciparum malaria disease manifestations in humans and transmission to anopheles gambiae: a field study in western kenya. | transmission of the malaria parasite plasmodium is influenced by many different host, vector and parasite factors. here we conducted a field study at mbita, an area of endemic malaria in western kenya, to test whether parasite transmission to mosquitoes is influenced by the severity of malaria infection in its human host at the time when gametocytes, the transmission forms, are present in the peripheral blood. we examined the infectivity of 81 plasmodium falciparum gametocyte carriers to mosquit ... | 2004 | 15074873 |
| the sick placenta-the role of malaria. | the human placenta is an ideal site for the accumulation of plasmodium falciparum malaria parasites, and as a consequence serious health problems arise for the mother and her baby. the pathogenesis of placental malaria is only partially understood, but it is clear that it leads to a distinct epidemiological pattern of malaria during pregnancy. the objectives of this review are: (1) to review recent data on the epidemiology of malaria in pregnancy, with emphasis on placental malaria; (2) to descr ... | 2004 | 15081631 |
| inactivation of protozoan parasites in red blood cells using inactine pen110 chemistry. | the transmission of parasites, including babesia, plasmodia, and trypanosoma cruzi, via transfusions is an important public health concern. inactine technology is a pathogen-reduction process that utilizes pen110, an electrophilic agent that inac-tivates a wide range of pathogens by disrupting nucleic acid replication. the present study investigated the effect of pen110 treatment on the viability of protozoa in rbcs. | 2004 | 15104655 |
| adenovirus serotype 3 utilizes cd80 (b7.1) and cd86 (b7.2) as cellular attachment receptors. | most viruses exploit a variety of host cellular proteins as primary cellular attachment receptors in the context of successful execution of infection. furthermore, many viral agents have evolved precise mechanisms to subvert host immune recognition to achieve persistence. herein we present data indicating that adenovirus (ad) serotype 3 utilizes cd80 (b7.1) and cd86 (b7.2) as cellular attachment receptors. cd80 and cd86 are co-stimulatory molecules that are present on mature dendritic cells and ... | 2004 | 15110532 |
| plasmodium falciparum-induced channels. | to survive within a red blood cell, the malaria parasite alters dramatically the permeability of the host's plasma membrane (allowing the uptake of essential nutrients and the removal of potentially hazardous metabolites). the pathway(s) responsible for the increased permeability have been proposed as putative chemotherapeutic targets and/or selective routes for antimalarial agents that target the internal parasite. this review covers our current understanding of this parasite-induced phenomenon ... | 2004 | 15111088 |
| proteomics in malaria. | the recent completion of human, anopheles gambiae, and plasmodium falciparum genomes relevant to the study of human malaria allows the application of modern proteomic technologies to complement previously implemented conventional approaches. proteomic analysis has been employed to elucidate global protein expression profiles, subcellular localization of gene products, and host-pathogen interactions that are central to disease pathogenesis and treatment. the high-throughput nature of these techni ... | 2004 | 15113107 |
| purification and partial characterization of pfhrp-ii protein of plasmodium falciparum. | the human malarial parasite plasmodium falciparum secretes various intra-and extra-cellular proteins during its asexual life cycle in human rbc. histidine rich protein-ii (hrp-ii) is one of the most prominent proteins, found to be secreted by p. falciparum throughout the asexual cycle with the peak during mature schizont stage of the parasite development in human irbc. the high histidine content (35% of the total amino acids in protein) of this protein suggested the potential to bind divalent me ... | 2003 | 15115081 |
| mutational analysis of the triclosan-binding region of enoyl-acp (acyl-carrier protein) reductase from plasmodium falciparum. | triclosan, a known antibacterial, acts by inhibiting enoyl-acp (acyl-carrier protein) reductase (enr), a key enzyme of the type ii fatty acid synthesis (fas) system. plasmodium falciparum, the human malaria-causing parasite, harbours the type ii fas; in contrast, its human host utilizes type i fas. due to this striking difference, enr has emerged as an important target for the development of new antimalarials. modelling studies, and the crystal structure of p. falciparum enr, have highlighted th ... | 2004 | 15139852 |
| orotate phosphoribosyltransferase and orotidine 5'-monophosphate decarboxylase exist as multienzyme complex in human malaria parasite plasmodium falciparum. | plasmodium falciparum, the causative agent of the most lethal form of human malaria, totally depends on de novo pyrimidine biosynthetic pathway. orotate phosphoribosyltransferase (oprt) and orotidine 5'-monophosphate decarboxylase (ompdc), the fifth and sixth enzymes in the pathway catalyzing formation of uridine 5'-monophosphate (ump), remain largely uncharacterized in the protozoan parasite. in this study, we achieved purification of oprt and ompdc to near homogeneity from p. falciparum cultiv ... | 2004 | 15147974 |
| transfection of the human malaria parasite plasmodium falciparum. | methods to transiently and stably transfect blood stages of the human malaria parasite plasmodium falciparum have been developed and adapted for gene-knockout, allelic replacement, and transgene expression in this organism. these methods are detailed in this chapter, as are approaches used to monitor transfectants during the selection process. the different plasmid vectors that are currently used for gene targeting and transgene expression (including green fluorescent protein expression) are als ... | 2004 | 15153633 |
| sphingolipid synthesis and membrane formation by plasmodium. | plasmodium falciparum is a protozoan parasite that causes the most virulent o f human malarias. the asexual blood-stage organism invades and multiplies in a vacuole in the mature erythrocyte. during intravacuolar growth, it induces the formation of a novel network o f tubovesicular membranes, the tvm, that is not present in uninfected red blood cells. recent data suggest that sphingomyelin biosynthesis by the parasite is an essential requirement for the assembly o f the tvm. furthermore, sphingo ... | 1996 | 15157523 |
| biochemical characterization and crystallization of recombinant 3-phosphoglycerate kinase of plasmodium falciparum. | human malaria parasite plasmodium falciparum depends largely on glycolytic pathway for energy metabolism during the intraerythrocytic life stage. therefore, enzymes of the glycolytic pathway could offer potential drug targets provided novel biochemical and/or structural features of the parasitic enzymes, which distinguish them from the host counterpart, could be identified. 3-phosphoglycerate kinase (ec 2.7.2.3) catalyzes an important phosphorylation step leading to the production of atp in the ... | 2004 | 15158737 |
| evaluation of a new plate hybridization assay for the laboratory diagnosis of imported malaria in italy. | a new molecular diagnostic method "malaria-ibridogen" (amplimedical s.p.a.--bioline division, turin, italy) based on a plate-hybridization assay for the simultaneous detection and identification of human malaria parasites was evaluated in this study. a target dna sequence of the plasmodial 18s ribosomal rna gene was amplified by polymerase chain reaction (pcr) and hybridized in microtiter wells with five biotinylated probes each specific for plasmodium falciparum, p. vivax, p. malariae, p. ovale ... | 2004 | 15164627 |
| dna phasing by ta dinucleotide microsatellite length determines in vitro and in vivo expression of the gp91phox subunit of nadph oxidase and mediates protection against severe malaria. | reactive oxygen intermediates (rois) play a major role in the nonspecific innate immune response to invading microorganisms, such as plasmodium falciparum. in a search for genetic markers that determine differences in production of roi, we detected a highly polymorphic region of dinucleotide ta repeats approximately 550 bp upstream of the nadph oxidase gp91(phox) subunit promoter. we genotyped 183 matched gabonese children with severe or mild malaria. repeat lengths ta(11) and ta(16) differed si ... | 2004 | 15181570 |
| light and electron microscopical observations of the effects of high-density lipoprotein on growth of plasmodium falciparum in vitro. | human serum high-density lipoprotein (hdl) is necessary and sufficient for the short-term maintenance of plasmodium falciparum in in vitro culture. however, at high concentrations it is toxic to the parasite. a heat-labile component is apparently responsible for the stage-specific toxicity to parasites within infected erythrocytes 12-42 h after invasion, i.e. during trophozoite maturation. the effects of hdl on parasite metabolism (as determined by nucleic acid synthesis) are evident at about 30 ... | 2004 | 15206459 |
| in vitro and in vivo antimalarial properties of isostrychnopentamine, an indolomonoterpenic alkaloid from strychnos usambarensis. | isostrychnopentamine (isp) is an asymmetric indolomonoterpenic alkaloid isolated from the leaves of strychnos usambarensis. the in vitro antiplasmodial activities against five plasmodium falciparum cell lines were evaluated: isp possessed an in vitro ic (50) near 0.1 microm against all p. falciparum cell lines tested (chloroquine-resistant and chloroquine-sensitive lines) and showed antiplasmodial selectivity compared to cytotoxicity on human cell lines. the stage-dependent susceptibility to a s ... | 2004 | 15229803 |
| question. do nos2 promoter polymorphisms protect against malaria? | | 2004 | 15230351 |
| transmission of malaria and its control in the northeastern region of india. | let alone the eradication, malaria control itself has amounted to be a challenge, and is detrimental to the all round development of the northeastern region of india. focal outbreaks are frequent taking heavy tool on human lives. plasmodium falciparum is the predominant parasite species and is solely responsible for increased morbidity and mortality. the region contributes bulk of p. falciparum cases for the rest of india, and its proportions are increasing. efficient vectors like anopheles mini ... | 2003 | 15260392 |
| synergistic and antagonistic interactions between haemozoin and bacterial endotoxin on human and mouse macrophages. | haemozoin (malaria pigment) is a birefringent crystalline material made of fe (iii) protoporphyrin ix dimers that derives from the degradation of haemoglobin by intraerythrocytic plasmodia. at schizont rupture, it accumulates indigested inside phagocytic cells altering their immunological properties. both pro-inflammatory and immunosuppressive activities have been associated with pigment-fed monocyte-macrophages or dendritic cells. these conflicting results were attributed to the source of macro ... | 2003 | 15267101 |
| novel antimalarial compounds isolated in a survey of self-medicative behavior of wild chimpanzees in uganda. | following a veterinary and behavioral survey of chimpanzees from a natural population in uganda, leaf samples of trichilia rubescens were collected because of the unusual method of ingestion observed. the methanolic crude extract of t. rubescens leaves exhibited significant antimalarial activity in vitro. bioassay-directed fractionation provided two new limonoids, trichirubines a and b. a greater understanding of the role of secondary compounds in the primate diet may be helpful in recovering na ... | 2004 | 15273150 |
| home improvements: malaria and the red blood cell. | in real-estate agent's terms, the red blood cell is a renovator's dream. the mature human erythrocyte has no internal organelles, no protein synthesis machinery and no infrastructure for protein trafficking. the malaria parasite invades this empty shell and effectively converts the erythrocyte back into a fully functional eukaryotic cell. in this article, michael foley and leann tilley examine the plasmodium falciparum proteins that interact with the membrane skeleton at different stages of the ... | 1995 | 15275396 |
| molecular dissection of the human antibody response to the structural repeat epitope of plasmodium falciparum sporozoite from a protected donor. | the circumsporozoite surface protein is the primary target of human antibodies against plasmodium falciparum sporozoites, these antibodies are predominantly directed to the major repetitive epitope (asn-pro-asn-ala)n, (npna)n. in individuals immunized by the bites of irradiated anopheles mosquitoes carrying p. falciparum sporozoites in their salivary glands, the anti-repeat response dominates and is thought by many to play a role in protective immunity. | 2004 | 15283866 |
| in vivo transcriptional profiling of plasmodium falciparum. | both host and pathogen factors contribute to disease outcome in plasmodium falciparum infection. the feasibility of studying the p. falciparum in vivo transcriptome to understand parasite transcriptional response while it resides in the human host is presented. | 2004 | 15296511 |
| crystallization of an intact monoclonal antibody (4b7) against plasmodium falciparum malaria with peptides from the pfs25 protein antigen. | monoclonal antibody 4b7 is a neutralizing antibody that binds the protein pfs25 in the sexual stages of the malaria parasite plasmodium falciparum and completely blocks transmission of the parasite from human serum to the mosquito host. here we report the identification of the epitope on pfs25 recognized by 4b7 and the crystallization of the intact murine monoclonal antibody with peptides corresponding to that epitope. this study highlights the importance of ligands in the crystallization of pro ... | 1994 | 15299418 |
| isolation and characterization of psalmopeotoxin i and ii: two novel antimalarial peptides from the venom of the tarantula psalmopoeus cambridgei. | two novel peptides that inhibit the intra-erythrocyte stage of plasmodium falciparum in vitro were identified in the venom of the trinidad chevron tarantula, psalmopoeus cambridgei. psalmopeotoxin i (pcfk1) is a 33-residue peptide and psalmopeotoxin ii (pcfk2) has 28-amino acid residues; both have three disulfide bridges and belong to the inhibitor cystine knot superfamily. the cdnas encoding both peptides were cloned, and nucleotide sequence analysis showed that the peptides are synthesized wit ... | 2004 | 15304333 |
| a plasmodium falciparum dipeptidyl aminopeptidase i participates in vacuolar hemoglobin degradation. | intraerythrocytic growth of the human malaria parasite plasmodium falciparum requires the catabolism of large amounts of host cell hemoglobin. endoproteolytic digestion of hemoglobin to short oligopeptides occurs in an acidic organelle called the food vacuole. how amino acids are generated from these peptides is not well understood. to gain insight into this process, we have studied a plasmodial ortholog of the lysosomal exopeptidase cathepsin c. the plasmodial enzyme dipeptidyl aminopeptidase 1 ... | 2004 | 15304495 |
| effect on antibody and t-cell responses of mixing five gmp-produced dna plasmids and administration with plasmid expressing gm-csf. | one potential benefit of dna vaccines is the capacity to elicit antibody and t-cell responses against multiple antigens at the same time by mixing plasmids expressing different proteins. a possible negative effect of such mixing is interference among plasmids regarding immunogenicity. in preparation for a clinical trial, we assessed the immunogenicity of gmp-produced plasmids encoding five plasmodium falciparum proteins, pfcsp, pfssp2, pfexp1, pflsa1, and pflsa3, given as a mixture, or alone. th ... | 2004 | 15318164 |
| identification of a polyclonal b-cell activator in plasmodium falciparum. | polyclonal b-cell activation and hypergammaglobulinemia are prominent features of human malaria. we report here that plasmodium falciparum-infected erythrocytes directly adhere to and activate peripheral blood b cells from nonimmune donors. the infected erythrocytes employ the cysteine-rich interdomain region 1alpha (cidr1alpha) of p. falciparum erythrocyte membrane protein 1 (pfemp1) to interact with the b cells. stimulation with recombinant cidr1alpha induces proliferation, an increase in b-ce ... | 2004 | 15322039 |
| role of the prevalent anopheles species in the transmission of plasmodium falciparum and p. vivax in assam state, north-eastern india. | in north-eastern india, anopheles minimus, an. dirus and an. fluviatilis are considered the three major vectors of the parasites causing human malaria. the role in transmission of the other anopheles species present in this region is not, however, very clear. to examine the vectorial role of the more common anopheline mosquitoes, the heads and thoraces of 4126 female anopheles belonging to 16 species (collected using miniature light traps set in human dwellings in a foothill village in the jorha ... | 2004 | 15324463 |
| genetic mapping in the human malaria parasite plasmodium falciparum. | the plasmodium falciparum genome sequence has boosted hopes for a new era of malaria research and for the application of comprehensive molecular knowledge to disease control, but formidable obstacles remain: approximately 60% of the predicted p. falciparum proteins have no known functions or homologues, and most life cycle stages of this haploid eukaryotic parasite are relatively intractable to cultivation and biochemical manipulation. genetic mapping based on high-resolution maps saturated with ... | 2004 | 15341640 |
| quantitative plasmodium sporozoite neutralization assay (tsna). | the circumsporozoite (cs) protein is the major surface protein of plasmodium sporozoites. antibodies to the immunodominant repeat domain of cs immobilize sporozoites and prevent infection of hepatocytes. plasmodium falciparum vaccines containing cs repeats are undergoing human trials in endemic areas, and proof of efficacy has been obtained. the correlates of protection are under investigation. levels of anti-repeat antibodies in the serum of the human volunteers have been measured mostly by enz ... | 2004 | 15350520 |
| identifying plasmodium falciparum eba-175 homologue sequences that specifically bind to human erythrocytes. | erythrocyte binding antigen-160 (eba-160) protein is a plasmodium falciparum antigen homologue from the erythrocyte binding protein family (ebp). it has been shown that the ebp family plays a role in parasite binding to the erythrocyte surface. the eba-160 sequence has been chemically synthesised in seventy 20-mer sequential peptides covering the entire 3d7 protein strain, each of which was tested in erythrocyte binding assays to identify possible eba-160 functional regions. five eba-160 high ac ... | 2004 | 15358103 |
| plasmodium falciparum: adherence of the parasite-infected erythrocytes to chondroitin sulfate proteoglycans bearing structurally distinct chondroitin sulfate chains. | infection with plasmodium falciparum during pregnancy leads to the selective adherence of infected red blood cells (irbcs) in the placenta causing placental malaria. the irbc adherence is mediated through the chondroitin 4-sulfate (c4s) chains of unusually low-sulfated chondroitin sulfate proteoglycans (cspgs) in the placenta. to study the structural interactions involved in c4s-irbc adherence, various investigators have used cspgs from different sources. since the structural characteristics of ... | 2004 | 15363944 |
| anthranoid compounds with antiprotozoal activity from vismia orientalis. | a phytochemical investigation of the 80% ethanolic extract of stem bark of vismia orientalis engl. (guttiferae or clusiaceae), a plant used in traditional medicine in tanzania, resulted in the isolation and spectroscopic characterisation of 3-geranyloxy-6-methyl-1,8-dihydroxyanthraquinone, emodin, vismione d and bianthrone a1. vismione d exhibited a broad range of antiprotozoal activities against trypanosoma brucei rhodesiense and t. cruzi (ic50 < 10 micrograms/ml), leishmania donovani (ic50 0.3 ... | 2004 | 15368649 |
| plasmodium falciparum malaria in splenectomized patients: two case reports in french guiana and a literature review. | some of the immunologic mechanisms involved in malaria physiopathology remain unclear. in animals, the spleen seems to play a key role in protecting the host against malaria. however, little is known about the effect of spleen dysfunction on human malaria. we report two severe cases of plasmodium falciparum infection with unusual clinical and parasitologic features in two splenectomized men living in french guiana. the peripheral blood of these cases showed hyperparasitemia, with a high proporti ... | 2004 | 15381808 |
| correct promoter control is needed for trafficking of the ring-infected erythrocyte surface antigen to the host cytosol in transfected malaria parasites. | following invasion of human erythrocytes, the malaria parasite, plasmodium falciparum, exports proteins beyond the confines of its own plasma membrane to modify the properties of the host red cell membrane. these modifications are critical to the pathogenesis of malaria. analysis of the p. falciparum genome sequence has identified a large number of molecules with putative atypical signal sequences. the signals remain poorly characterized; however, a number of molecules with these motifs localize ... | 2004 | 15385514 |
| chondroitin sulfate proteoglycans of bovine cornea: structural characterization and assessment for the adherence of plasmodium falciparum-infected erythrocytes. | the structures of the bovine corneal chondroitin sulfate (cs) chains and the nature of core proteins to which these chains are attached have not been studied in detail. in this study, we show that structurally diverse cs chains are present in bovine cornea and that they are mainly linked to decorin core protein. deae-sephacel chromatography fractionated the corneal chondroitin sulfate proteoglycans (cspgs) into three distinct fractions, cspg-i, cspg-ii, and cspg-iii. these cspgs markedly differ ... | 2004 | 15450180 |
| malaria: living with drug resistance. | the epidemiological factors associated with the development and spread of drug-resistant malaria have been recently explored by wemsdorfer in a paper in which he looked at parasite-drug-human-vector interactions that affect the occurrence and dynamics of drug resistance. the question that decision-makers must be asking themselves, as we face the 21st century, is: how will we live with drug resistance? allan schapira, peter beales and m. elizabeth halloran are ideally placed to consider this ques ... | 1993 | 15463746 |
| eleven years of malaria surveillance in a sudanese village highlights unexpected variation in individual disease susceptibility and outbreak severity. | an analysis is presented of continuous data collected over 11 years based on 1,902,600 person/days of observation on the malaria experience of the people of daraweesh, a village in eastern sudan. malaria transmission is hypo-endemic: the acquisition of clinical immunity with age is not as obvious as in more holo-endemic areas and malaria remained a problem in all age groups throughout the study. however, this population, who are of fulani origin, showed a distinctly variable level of disease sus ... | 2004 | 15471002 |
| crystal structure of s-adenosyl-l-homocysteine hydrolase from the human malaria parasite plasmodium falciparum. | the human malaria parasite plasmodium falciparum is responsible for the death of more than a million people each year. the emergence of strains of malarial parasite resistant to conventional drug therapy has stimulated searches for antimalarials with novel modes of action. s-adenosyl-l-homocysteine hydrolase (sahh) is a regulator of biological methylations. inhibitors of sahh affect the methylation status of nucleic acids, proteins, and small molecules. p.falciparum sahh (pfsahh) inhibitors are ... | 2004 | 15476817 |
| myosin-like sequences in the malaria parasite plasmodium falciparum bind human erythrocyte membrane protein 4.1. | plasmodium falciparum malaria is one of the most lethal infectious diseases afflicting humanity. during development within the erythrocyte, p. falciparum induces significant modifications to the structure and function of the human erythrocyte membrane. this study focused on the identification of new protein-protein interactions between host and parasite. | 2004 | 15477199 |