| the drug sensitivity and transmission dynamics of human malaria on nias island, north sumatra, indonesia. | nias island, off the north-western coast of sumatra, indonesia, was one of the first locations in which chloroquine-resistant plasmodium vivax malaria was reported. this resistance is of particular concern because its ancient megalithic culture and the outstanding surfing conditions make the island a popular tourist destination. international travel to and from the island could rapidly spread chloroquine-resistant strains of p. vivax across the planet. the threat posed by such strains, locally a ... | 2002 | 12194705 |
| transition of plasmodium vivax ribosome types corresponds to sporozoite differentiation in the mosquito. | two distinct small subunit ribosomal rna (ssurrna) genes were amplified from the genomic dna of plasmodium vivax. comparison of the two coding sequences reveals an overall divergence of 14.5% and most differences are clustered into the regions known to diverge rapidly in all eukaryotic ssurrnas. oligonucleotides complementary to unique sequences of each gene have been used to distinguish the transcripts expressed either at schizogony in human blood (a gene) or at sporogony in the mosquito (c gen ... | 1994 | 7969269 |
| variation of the vectorial capacity of some anophelines in western venezuela. | the vectorial capacities of anopheles nuneztovari, an. albitarsis s.l., and an. triannulatus to transmit plasmodium vivax in western venezuela were estimated in different seasons. in general, there was a decrease in the vectorial capacities of the three species during the dry season, which seems to be due mainly to a reduction in the mosquito biting populations. comparing the observations made during the two wet seasons, there was a decrease in the vectorial capacities of the three species due t ... | 1994 | 8166348 |
| the epidemiology of plasmodium vivax circumsporozoite protein polymorphs in thailand. | enzyme-linked immunosorbent assays (elisas) highly specific for the characteristic repeat units of the circumsporozoite proteins of the vk 247 and vk 210 polymorphs of plasmodium vivax were used to test sporozoites produced by feeding mosquitoes on 1,711 human volunteers presenting at four locations in thailand over five years. there was no evidence for the existence of any polymorph other than the two already described. based on the elisas, the overall prevalence of the vk 247 type was 29.5%, i ... | 1994 | 8166353 |
| diagnosis of plasmodium vivax malaria complicated by abnormal neurological imaging. | the number of patients presenting with malaria in the united states has increased. this is attributable to the growing ease and popularity of overseas travel. we present a 41-year-old man diagnosed with plasmodium vivax malaria after a 9-month symptom-free interval following return from an endemic area. the clinical picture was complicated by the results of neurological imaging that proved to be incidental and unrelated findings. unfortunately, there are no pathognomonic signs or symptoms of mal ... | 2002 | 12502181 |
| royal society of tropical medicine and hygiene meeting at manson house, london, 10 december 1992. george carmichael low frcp: twelfth president of the society and underrated pioneer of tropical medicine. | george carmichael low, like so many early pioneers of tropical medicine, had his origin(s) in scotland. following a distinguished undergraduate (and early postgraduate) career, he joined dr patrick manson at the newly established london school of tropical medicine in 1899. his first major contribution to the specialty (in 1900) was to demonstrate filariae in the proboscis sheath of mosquitoes which had been infected with filaria bancrofti in australia, using a technique recently learned in heide ... | 1993 | 8249057 |
| purification of a 28 kd non-aggregating tryptic peptide of the duffy blood group protein. | duffy blood group antigenic epitopes are located on a 35-43 kd integral membrane protein of the erythrocyte membrane. this protein functions as a receptor for the human malaria parasite, plasmodium vivax. the duffy protein has been difficult to purify because of its tendency to form aggregates. here we describe purification of a 28 kd tryptic fragment of the duffy protein and purification of an 18 kd de-glycosylated form of the duffy tryptic peptide using thiopropyl sepharose 6b chromatography a ... | 1993 | 8484749 |
| cytokine-mediated inactivation of malarial gametocytes is dependent on the presence of white blood cells and involves reactive nitrogen intermediates. | supernatants of human peripheral blood mononuclear cells (pbmc) incubated for 24 hr in the presence of extracts of freeze-thawed blood stage parasites of plasmodium vivax or p. falciparum mediate inactivation of gametocytes of either species when incubated in vitro with whole human blood cells. cultured p. falciparum gametocytes incubated with these malaria extract-stimulated pbmc supernatants in the presence of human blood from which white blood cells (wbc) had been removed were not inactivated ... | 1993 | 8495973 |
| regulation and trafficking of three distinct 18 s ribosomal rnas during development of the malaria parasite. | the human malaria parasite plasmodium vivax has been shown to regulate the transcription of two distinct 18 rnas during development. here we show a third and distinctive type of ribosome that is present shortly after zygote formation, a transcriptional pattern of ribosome types that relates closely to the developmental state of the parasite and a phenomenon that separates ribosomal types at a critical phase of maturation. the a-type ribosome is predominantly found in infected erythrocytes of the ... | 1997 | 9191065 |
| interactions of human malaria parasites, plasmodium vivax and p.falciparum, with the midgut of anopheles mosquitoes. | present understanding of the development of sexual stages of the human malaria parasites plasmodium vivax and p.falciparum in the anopheles vector is reviewed, with particular reference to the role of the mosquito midgut in establishing an infection. the sexual stages of the parasite, the gametocytes, are formed in human erythrocytes. the changes in temperature and ph encountered by the gametocyte induce gametogenesis in the lumen of the midgut. macromolecules derived from mosquito tissue and se ... | 1997 | 9330262 |
| cross-species regulation of plasmodium parasitemia in semi-immune children from papua new guinea. | malariologists have long been fascinated by the question of whether plasmodium spp. interact in the human host. the first genetic study of the longitudinal dynamics of multiple plasmodium spp. and genotypes in humans has been completed in papua new guinea, where all four plasmodium spp. that infect humans are present. the broad implications of the data from this study are covered here and they show that the total parasite density of plasmodium species oscillates around a threshold and that peaks ... | 2003 | 12798085 |
| the erythrocyte binding motif of plasmodium vivax duffy binding protein is highly polymorphic and functionally conserved in isolates from papua new guinea. | the duffy binding protein (dbp) of plasmodium vivax is a critical adhesion ligand that participates in merozoite invasion of human duffy positive reticulocytes. binding domains have been shown to lie within a conserved n-terminal cyteine-rich region, region ii, that contains 330-aa and the critical binding residues have been recently mapped to 170-aa stretch within this region. previous studies on few isolates indicated a significant degree of polymorphism in region ii (dbpii). to examine furthe ... | 2000 | 11163434 |
| a novel mutation in the coding sequence of the fy*b allele of the duffy chemokine receptor gene is associated with an altered erythrocyte phenotype. | the duffy blood group system is of clinical and biological significance. antibodies to duffy antigens are responsible for some cases of transfusion incompatibility and newborn hemolytic disease. the duffy protein is a receptor for the plasmodium vivax erythrocyte-binding protein and is also a receptor for various chemokines (thus renamed duffy antigen receptor for chemokines [darc]). the two duffy polymorphic antigens, fya and fyb (coded by the fy*a and fy*b alleles), are present on erythrocyte ... | 1998 | 9746760 |
| 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 |
| malaria transmission potential by anopheles sinensis in the republic of korea. | to evaluate the factors that determine the transmission level of vivax malaria using vectorial capacity, entomological surveys were conducted from june to august, 2000. from 6 nights of human-bait collection in paju, the human biting rate (ma) was counted as 87.5 bites/man/night. the parity of anopheles sinensis from human baiting collections fluctuated from 41% to 71% (average 48.8%) of which the rate gradually increased as time passed on: 35.2% in jun.; 55.0% in july; 66.2% in aug. from this p ... | 2001 | 11441506 |
| the impact of indoor residual spraying with malathion on malaria in refugee camps in eastern sudan. | an exploratory trial of the efficacy of indoor spraying with malathion on morbidity and mortality in refugee camps in eastern sudan was conducted during the rainy season of 1997. the interior walls of houses from a randomly selected group of five camps were sprayed with malathion in mid-september and morbidity and mortality rates in the camps for the months october to december compared with rates in five controls. pyrethrum spray collection and human landing catches were performed in two collect ... | 2001 | 11495638 |
| correlation between positive serology for plasmodium vivax-like/plasmodium simiovale malaria parasites in the human and anopheline populations in the state of acre, brazil. | antibodies against the plasmodium vivax-like/p. simiovale malaria parasite circumsporozoite repeat peptide (apganqeggaa)3 were determined by enzyme-linked immunosorbent assay (elisa) in 120 sera randomly collected in 1994 from adults in 3 localities of the malaria endemic area in the state of acre, brazil; antibody was detected in 18 (15%). a 'sandwich' elisa using monoclonal antibody (mab) pam 172, directed against the same peptide, was carried out on 1207 anopheles oswaldoi, 12 of which (1.0%) ... | 1998 | 9764317 |
| 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 |
| studies in human malaria. xxx. a summary of 204 sporozoite-induced infections with the chesson strain of plasmodium vivax. | | 1950 | 14804098 |
| development and optimization of polymerase chain reaction-based malaria diagnostic methods and their comparison with quantitative buffy coat assay. | polymerase chain reaction (pcr)-based assays targeting the small-subunit rrna were developed and evaluated, allowing for the simultaneous diagnosis of plasmodium falciparum and plasmodium vivax dna in human blood samples. the pcr methods and quantitative buffy coat (qbc) were compared in 402 patients. the heminested pcr method showed a sensitivity of 97.4%, which was superior to the sensitivity of the qbc method (91.7%, p < 0.05), to simple pcr (84.6%, p < 0.001), and to pcr with digoxigenin lab ... | 2001 | 11693884 |
| why is the pathology of falciparum worse than that of vivax malaria? | here, ian clark and bill cowden summarize new evidence suggesting that nitric oxide (no) generated by inducible no synthase (inos) provides a functional link between the previously competing approaches to malarial disease pathogenesis: ischaemic hypoxia and no. when combined with the newly recognized roles of inos in renal and pulmonary function and glucose metabolism, synergy between inflammatory cytokines and hypoxia in inos induction provides a framework to help explain, at a molecular level, ... | 1999 | 10511689 |
| 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 |
| detection of vivax malaria sporozoites naturally infected in anopheline mosquitoes from endemic areas of northern parts of gyeonggi-do (province) in korea. | we investigated population densities of mosquitoes infected with sporozoites in three highly epidemic areas of josan-ri and jangpa-ri (paju city) and dongjung-ri (yeoncheon county) in korea. anopheline mosquitoes were collected from both indoors and outdoors by human baiting collection method during the period of the first week of june to the second week of september 1999. total 13,296 female mosquitoes were collected and 8,650 (65.1%) were anophelines. thirty seven percent (3,199) of the anophe ... | 2002 | 12073732 |
| emergence of fy*a(null) in a plasmodium vivax-endemic region of papua new guinea. | in papua new guinea (png), numerous blood group polymorphisms and hemoglobinopathies characterize the human population. human genetic polymorphisms of this nature are common in malarious regions, and all four human malaria parasites are holoendemic below 1500 meters in png. at this elevation, a prominent condition characterizing melanesians is alpha(+)-thalassemia. interestingly, recent epidemiological surveys have demonstrated that alpha(+)-thalassemia is associated with increased susceptibilit ... | 1999 | 10570183 |
| sequence and expression of mhc-dpb1 molecules of the new world monkey aotus nancymaae, a primate model for plasmodium falciparum. | aotus nancymaae represents an animal model for the pre-clinical evaluation of blood-stage vaccine candidates against plasmodium falciparum and plasmodium vivax. we present here the nucleotide sequences of exon 2 and 3 of mhc-dpb1 genes. in a group of seven unrelated animals captured in the wild, three alleles of mhc-dpb1 exon 2 could be identified. phylogenetic analysis shows that in contrast to aona- drb and - dqb, the aona-dpb1exon 2 amino acid sequences cluster in a species-specific manner. n ... | 2002 | 12136336 |
| malaria prevalence and a brief entomological survey in a village surrounded by rice fields in khammouan province, lao pdr. | we surveyed nongceng, a village in a south-eastern province of lao pdr, for malaria and its vectors. nongceng is situated in a basin and surrounded by rice fields. in february 1998 (dry season), 28.6% of 126 villagers were infected with malaria, and in september 1998 (rainy season), 16.3% of 147 villagers. the prevalence of malaria infection was consistently high in children under 10, and the predominant malaria species was plasmodium falciparum. in brief surveys of the mosquitoes performed on t ... | 2000 | 10672201 |
| malaria diseases and parasites. | the milestones in the discovery of malaria parasites and their relationships with malaria diseases are presented and discussed with particular reference to the contribution of the italian scientists. laveran's discovery (1880) of the malaria parasite produced some schepticism among the roman scientists who were under the influence of tommasi-crudeli, the discoverer of the supposed bacillus malariae. however, marchiafava and celli confirmed soon laveran's observations and, between 1883 and 1885, ... | 1999 | 10697831 |
| using live pathogens to treat infectious diseases: a historical perspective on the relationship between gb virus c and hiv. | recent reports that co-infection with gb virus c (gbv-c) is associated with a reduced mortality in hiv-infected individuals, a slower progression to aids, and lower hiv viral loads, suggest a potential role of gbv-c as therapy for hiv infection. although not known to cause any human disease, gbv-c was only recently discovered and prospective studies assessing long-term consequences of infection have not been completed. our understanding of the host-viral interactions between humans and gbv-c is ... | 2002 | 12212927 |
| comparative characterization of hexose transporters of plasmodium knowlesi, plasmodium yoelii and toxoplasma gondii highlights functional differences within the apicomplexan family. | chemotherapy of apicomplexan parasites is limited by emerging drug resistance or lack of novel targets. pfht1, the plasmodium falciparum hexose transporter 1, is a promising new drug target because asexual-stage malarial parasites depend wholly on glucose for energy. we have performed a comparative functional characterization of pfht1 and hexose transporters of the simian malarial parasite p. knowlesi (pkht1), the rodent parasite p. yoelii (pyht1) and the human apicomplexan parasite toxoplasma g ... | 2002 | 12238947 |
| aotus monkeys: their great value for anti-malaria vaccines and drug testing. | non-human primates represent a valuable resource for testing potential vaccines candidates and drugs for human use. malaria remains one of the greatest burdens for the humanity represented by approximately 500 million new clinical cases per year worldwide and at least two million deaths caused annually. additional control measures such as vaccines and new anti-malarial compounds are therefore urgently needed. safety and protective efficacy studies in animal models are critical steps for vaccines ... | 2002 | 12435447 |
| evolution and disease. | a recent meeting highlighted how much darwinian thinking on natural selection illuminates the background to some major current human diseases and may offer insight into many more. nigel williams reports on a field seeking a place in mainstream medical education. | 2003 | 12526752 |
| pre-erythrocytic malaria vaccine: mechanisms of protective immunity and human vaccine trials. | in order to provide a rational basis for the development of a pre-erythrocytic malaria vaccine we have aimed at: (a) elucidating the mechanisms of protection, and (b) identifying vaccine formulations that best elicit protection in experimental animals and humans. based on earlier successful immunization of experimental animals with irradiated sporozoites, human volunteers were exposed to the bites of large numbers of plasmodium falciparum or p. vivax infected irradiated mosquitoes. the result of ... | 1999 | 10697892 |
| international union of pharmacology. xxii. nomenclature for chemokine receptors. | chemokine receptors comprise a large family of seven transmembrane domain g protein-coupled receptors differentially expressed in diverse cell types. biological activities have been most clearly defined in leukocytes, where chemokines coordinate development, differentiation, anatomic distribution, trafficking, and effector functions and thereby regulate innate and adaptive immune responses. pharmacological analysis of chemokine receptors is at an early stage of development. disease indications h ... | 2000 | 10699158 |
| impact of ddt spraying on malaria transmission in bareilly district, uttar pradesh, india. | impact of indoor residual spraying of ddt on malaria transmission and vector density was evaluated in six villages of shergarh phc, bareilly district, uttar pradesh under the operational condition of national vector borne disease control programme (nvbdcp) from july 2001 to march 2002 (one transmission season only). | 2005 | 16161701 |
| biting behavior and plasmodium infection rates of anopheles arabiensis from sille, ethiopia. | the man-biting behavior and plasmodium infection rates of anopheline mosquitoes were investigated in sille, a hyperendemic malarious area in southern ethiopia. seven anopheles species were identified from all night landing collections, conducted from 18:00 to 06:00h between october 2001 and august 2002. the predominant species was anopheles arabiensis (55.8%), followed by anopheles coustani (31.5%), anopheles pharoensis (9.5%), anopheles funestus (2.2%), anopheles nili (0.5%), anopheles marshall ... | 2006 | 16171769 |
| [blood groups and disease]. | the erythrocyte membrane was used as general model for the plasma membrane knowledge. some of their structures are antigens from blood group systems being characterized at molecular and functional level as specific receptors, transporters or enzymes, even receptors for infectious agents. plasmodium vivax malarial parasites require the duffy blood group glycoprotein to penetrate into human red blood cells and the main antigen of p system (p1) is also the parvovirus b19 receptor. furthermore, thes ... | 2005 | 16185549 |
| variant proteins of plasmodium vivax are not clonally expressed in natural infections. | plasmodium vivax is the most widely distributed human malaria parasite and responsible for 70-80 million clinical cases each year and a large socio-economical burden. the sequence of a chromosome end from p. vivax revealed the existence of a multigene superfamily, termed vir (p. vivax variant antigens), that can be subdivided into different subfamilies based on sequence similarity analysis and which represents close to 10-20% of the coding sequences of the parasite. here we show that there is a ... | 2005 | 16238616 |
| status of malaria in thailand. | despite decades of control success and a competent network of country-wide health infrastructure, malaria remains an important health threat in rural thailand. all 4 known human malaria parasites have been reported present, with plasmodium falciparum and plasmodium vivax predominant. the expansion and intensity of multi-drug resistant plasmodium falciparum is the most serious development to occur the last several decades. members of 3 anopheline species complexes, anopheles dirus, anopheles mini ... | 2000 | 11127318 |
| slam: cross-species gene finding and alignment with a generalized pair hidden markov model. | comparative-based gene recognition is driven by the principle that conserved regions between related organisms are more likely than divergent regions to be coding. we describe a probabilistic framework for gene structure and alignment that can be used to simultaneously find both the gene structure and alignment of two syntenic genomic regions. a key feature of the method is the ability to enhance gene predictions by finding the best alignment between two syntenic sequences, while at the same tim ... | 2003 | 12618381 |
| evidence for diversifying selection on erythrocyte-binding antigens of plasmodium falciparum and p. vivax. | malaria parasite antigens involved in erythrocyte invasion are primary vaccine candidates. the erythrocyte-binding antigen 175k (eba-175) of plasmodium falciparum binds to glycophorin a on the human erythrocyte surface via an n-terminal cysteine-rich region (termed region ii) and is a target of antibody responses. a survey of polymorphism in a malaria-endemic population shows that nucleotide alleles in eba-175 region ii occur at more intermediate frequencies than expected under neutrality, but p ... | 2003 | 12702678 |
| impact of imported malaria on the burden of disease in northeastern venezuela. | many countries throughout the world are reporting an increasing number of imported malaria cases. it is now well documented that population movements play an important role in the spread and introduction of malaria infection in nonendemic areas. | 2006 | 16412105 |
| speculations on the origins of plasmodium vivax malaria. | it is likely that plasmodium vivax diverged approximately 2 million years ago from a group of malaria parasites which are now endemic in monkeys and apes in southern asia. in those times, primates were spread throughout most of eurasia and africa, indicating an old world location, but nothing more precise, for the place of divergence of p. vivax. from approximately 1 million years ago, the ice ages would have isolated human malaria, including p. vivax, into humid temperate or warm climate refuge ... | 2003 | 12763427 |
| widespread occurrence of antibodies against circumsporozoite protein and against blood forms of plasmodium vivax, p. falciparum and p. malariae in brazilian wild monkeys. | a survey of malaria antibodies was carried out over 7 years and a total of 777 serum samples from wild monkeys were collected in three distinct ecological areas of brazil where autochthonous malaria has been reported: the 'cerrado' (similar to savanna), the atlantic forest and the atlantic semideciduous forest. | 2006 | 16556295 |
| validation of the hexose transporter of plasmodium falciparum as a novel drug target. | chemotherapy of malaria parasites is limited by established drug resistance and lack of novel targets. intraerythrocytic stages of plasmodium falciparum are wholly dependent on host glucose for energy. glucose uptake is mediated by a parasite-encoded facilitative hexose transporter (pfht). we report that o-3 hexose derivatives inhibit uptake of glucose and fructose by pfht when expressed in xenopus oocytes. selectivity of these derivatives for pfht is confirmed by lack of inhibition of hexose tr ... | 2003 | 12792024 |
| sequence variations in the plasmodium vivax dihydrofolate reductase-thymidylate synthase gene and their relationship with pyrimethamine resistance. | the gene encoding dihydrofolate reductase-thymidylate synthase of the human malaria parasite, plasmodium vivax, was isolated by polymerase chain reaction from genomic dna and cloned. the sequences of the dihydrofolate reductase domain of 30 clinical isolates originating from various geographic areas were compared. interstrain analysis revealed several genotypic variations, including short tandem repeat arrays which produced length polymorphism between different parasite isolates and point mutati ... | 1998 | 9657331 |
| procedure and clinical assessments of malariotherapy: recent experience in 20 hiv patients. | to demonstrate the side effects of malariotherapy and to explore safe procedures in conduct of malariotherapy for human immunodeficiency virus (hiv) infected patients. | 2003 | 12890375 |
| therapeutic trials of a dihydroxynaphthalene (377c54) against plasmodiumfalciparum and plasmodium vivax infections in human volunteers. | | 1963 | 14044762 |
| storage of human and rodent blood smears of malaria parasites. | | 1964 | 14154271 |
| sequence, evolution and ligand binding properties of mammalian duffy antigen/receptor for chemokines. | the duffy antigen/ receptor for chemokine, darc, acts as a widely expressed promiscuous chemokine receptor and as the erythrocyte receptor for plasmodium vivax. to gain insight into the evolution and structure/function relations of darc, we analyzed the binding of anti-human fy monoclonal antibodies (mabs) and human chemokines to red blood cells (rbcs) from 11 nonhuman primates and two nonprimate mammals, and we elucidated the structures of the darc genes from gorilla, gibbon, baboon, marmoset, ... | 2004 | 14712331 |
| 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 |
| malaria epidemiology in low-endemicity areas of the atlantic forest in the vale do ribeira, são paulo, brazil. | we describe a seroepidemiological survey of malaria prevalence in two areas of low endemicity: intervales state park and alto ribeira state tourist park (petar). both are located in the vale do ribeira in the state of são paulo, brazil. in this study, 318 subjects from both areas had their blood analyzed for the presence of malaria parasites by thin and thick blood smears. one hundred and sixty-three (51.2%) of the subjects were from intervales state park and 155 (48.7%) were from petar. we anal ... | 2006 | 17126279 |
| the ecological characteristics of anopheles mosquitoes associated with low malaria transmission in siwa oasis, egypt. | the ecology of anopheles sergentii and an. multicolor was investigated over eight months to examine the entomological factors maintaining the low plasmodium vivax transmission in siwa oasis. the two species were encountered as larvae while the dominant species, anopheles sergentii was also collected as adults. breeding sites were characterized for the two species in six localities. larvae of both species were common during june and november. in bahi el din as an indicator village with a higher e ... | 1996 | 17217007 |
| 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 |
| identification, expression, modeled structure and serological characterization of plasmodium vivax histone 2b. | histones play important role in dna packaging, replication and gene expression. here, we describe the isolation and characterization of histone 2b (pvh2b) gene from the most common but non-cultivable human malaria parasite plasmodium vivax. the isolated cdna clone of pvh2b was allowed to express in escherichia coli and the recombinant protein was purified by affinity chromatography. the expressed pvh2b protein showed dna-binding properties on the south-western analysis and the confocal microscop ... | 2004 | 15276199 |
| potent immunogenicity of dna vaccines encoding plasmodium vivax transmission-blocking vaccine candidates pvs25 and pvs28-evaluation of homologous and heterologous antigen-delivery prime-boost strategy. | transmission-blocking vaccines target the sexual stages of the malaria parasite and prevent further development within the mosquito vector halting the transmission of the parasite. zygote/ookinetes are potential targets of antibodies inhibiting oocyst development in the mosquito midgut and rendering mosquitoes non-infectious. dna vaccine constructs were developed expressing pvs25 and pvs28 (plasmodium vivax zygote/ookinete surface proteins) fused at the amino terminus with tissue plasminogen act ... | 2004 | 15297075 |
| 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 |
| review: the kell, duffy, and kidd blood group systems. | after the discovery (over 50 years ago) that the iat could be applied to the detection of antibodies to blood group antigens, there was a rapid increase in the identification of alloantibodies that caused transfusion reactions or hdn. after rh, antibodies in the kell, duffy, and kidd blood group systems were the next in clinically significant antibodies to be revealed. much of what has been learned about these blood groups since the journal immunohematology issued its first edition has to do wit ... | 2004 | 15373667 |
| an epitope-specific pcr test for diagnosis of leishmania donovani infections. | the carboxy-terminal region of recombinant heat shock protein 70 of leishmania donovani has been shown to have an immunodominant epitope. we designed a pcr assay using a new set of primers encompassing the gene sequence from 457bp to 927bp, which amplified a segment of the l. donovani genome in a species-specific manner. the assay was sensitive enough to detect 0.5pg of parasite dna, which increased 10-fold (0.05pg) when an internal probe (583-609bp) was used in the southern blot. the assay was ... | 2008 | 17888473 |
| physiographic and entomologic risk factors of malaria in assam, india. | fever surveys were conducted in several districts of the indian state of assam to ascertain the prevalence of malaria in relation to vector abundance, entomologic inoculation rates (eirs), and geographic location of human settlements. anopheles minimus were incriminated, but their relative abundance and biting rates varied among districts, and no significant correlation was observed between these two indicators (r = 0.43, p = 0.34). plasmodium falciparum was the predominant parasite species exce ... | 2004 | 15516642 |
| [spontaneous spleen rupture in the course of malaria]. | the spontaneous rupture of malarial spleen is an uncommon complication. it usually occurs to a child and a recent expatriate. its diagnosis is misleading into a context of infection. a 28-year-old european man, newly affected to gabon, under chimioprophylactic drugs by chloroquine and proguanil, has been hospitalized in september 2000 because of an acute attack of malaria to plasmodium falciparum. after four days treatment by quinine, he presented an abdominal pain with a sub capsular haematoma ... | 2008 | 18079082 |
| plasmodium vivax invasion of human erythrocytes inhibited by antibodies directed against the duffy binding protein. | plasmodium vivax invasion requires interaction between the human duffy antigen on the surface of erythrocytes and the p. vivax duffy binding protein (pvdbp) expressed by the parasite. given that duffy-negative individuals are resistant and that duffy-negative heterozygotes show reduced susceptibility to blood-stage infection, we hypothesized that antibodies directed against region two of p. vivax duffy binding protein (pvdbpii) would inhibit p. vivax invasion of human erythrocytes. | 2007 | 18092885 |
| an outbreak of malaria in us army rangers returning from afghanistan. | with numerous us military personnel currently deployed throughout the world, military and civilian health care professionals may encounter imported malaria from this population. | 2005 | 15644548 |
| vectors and malaria transmission in a gem mining area in sri lanka. | anopheline vectors of malaria were studied in the kaluganga gem mining area in the dry zone of central sri lanka. adult mosquitoes were collected using cattle-baited huts and nets, pyrethrum spray sheets, window exit traps and light traps and partial and full-night human landing collections over a period of 17 mo. the collections produced a total of 13,591 anophelines belonging to 14 species. using elisa for circumsporozoite proteins of plasmodium vivax and p. falciparum, anopheles culicifacies, ... | 2004 | 15707286 |
| [camillo golgi and the contribution of the italian scientists to the development of the malariology in the last quarter of the nineteenth century]. | between 1885 and 1892--a period in which great advances have been made in techniques and practice of the young science of microbiology--camillo golgi provided a notable contribution to malariology. continuing studies and researches of roman malariologists ettore marchiafava (1847-1935) and angelo celli (1857-1914), on the malarial parasites--described by the french military physician alphonse laveran--he studied the reproduction cycles of the plasmodium in human blood (golgi cycles) and elucidat ... | 2007 | 18447170 |
| spatio-temporal distribution of plasmodium falciparum and p. vivax malaria in thailand. | malaria incidence data at the district level from 1997 to 2002 and total malaria case data from 1965 to 2002 in thailand were analyzed to determine the spatial and temporal dynamics of plasmodium falciparum and p. vivax malaria incidence. over the 37-year period, there was a 35-fold reduction in the incidence rates of p. falciparum malaria (11.86% in 1965 versus 0.34% in 2002) and a 7-fold reduction in p. vivax malaria (2.89% in 1965 versus 0.40% in 2002). the incidence ratio of p. falciparum to ... | 2005 | 15772317 |
| plasmodium vivax apical membrane antigen-1: comparative recognition of different domains by antibodies induced during natural human infection. | the apical membrane antigen-1 (ama-1) of plasmodium sp. has been suggested as a vaccine candidate against malaria. this protein seems to be involved in merozoite invasion and its extra-cellular portion contains three distinct domains: di, dii, and diii. previously, we described that plasmodium vivax ama-1 (pvama-1) ectodomain is highly immunogenic in natural human infections. here, we expressed each domain, separately or in combination (di-ii or dii-iii), as bacterial recombinant proteins to map ... | 2008 | 18692152 |
| expression of duffy antigen receptor for chemokines during reticulocyte maturation: using a cd71 flow cytometric technique to identify reticulocytes. | flow cytometric methods commonly used to identify reticulocytes are of limited usefulness in malarious areas, since rna staining also detects plasmodia. an important antigen expressed on reticulocytes is duffy antigen receptor for chemokines (darc, also known as fy), the receptor for plasmodium vivax. an early marker for reticulocytes is cd71 (transferrin receptor). we have been interested in cd71 as an alternative marker for reticulocytes in the context of fy expression. flow cytometry was used ... | 2005 | 15783301 |
| studies on the chemotherapy of the human malarias the metabolism of cinchonine in relation to its antimalarial activity. | | 1948 | 18860185 |
| retrospective study of malaria prevalence and anopheles genus in the area of influence of the binational itaipu reservoir. | the importance of hydroelectric dams beside the human interchange in the maintenance of malarious foci and the occurrence of the anopheles genus on the binational itaipu reservoir were the main points of this retrospective study. data were collected from existing registrations at national, state and municipal health departments and literature systematic overview, from january 1984 to december 2003. the occurrence of some outbreak of malaria, mainly by plasmodium vivax, and the prevalence of spec ... | 2005 | 15880218 |
| epidemiological and ecological aspects related to malaria in the area of influence of the lake at porto primavera dam, in western são paulo state, brazil. | a study was carried out in the area of influence of the porto primavera hydroelectric power station, in western são paulo state, to investigate ecological and epidemiological aspects of malaria in the area and monitor the profile of the anopheline populations following the environmental changes brought about by the construction of the lake. mosquitoes captured were analyzed by standardized indicator species analysis (isa) before and during different flooding phases (253 m and 257 m elevations). ... | 2008 | 18949348 |
| mitochondrial genome sequences support ancient population expansion in plasmodium vivax. | examination of nucleotide diversity in 106 mitochondrial genomes of the most geographically widespread human malaria parasite, plasmodium vivax, revealed a level of diversity similar to, but slightly higher than, that seen in the virulent human malaria parasite plasmodium falciparum. the pairwise distribution of nucleotide differences among mitochondrial genome sequences supported the hypothesis that both these parasites underwent ancient population expansions. we estimated the age of the most r ... | 2005 | 15901839 |
| chimeric epitopes delivered by polymeric synthetic linear peptides induce protective immunity to malaria. | polymeric linear peptide chimeras (lpcs) that incorporate plasmodium vivax promiscuous t cell epitopes and the p. falciparum circumsporozoite protein b cell epitope have been shown to induce a high level of immunogenicity and overcome genetic restriction when tested as vaccine immunogens in balb/c mice. the present study evaluates the biological relevance of several lpcs using a well characterized rodent malaria model. polymeric peptide constructs based on p. berghei and p. yoelii sequences, and ... | 2005 | 16253535 |
| genetic polymorphisms in tlr4, cr1 and duffy genes are not associated with malaria resistance in patients from baixo amazonas region, brazil. | the main purpose of this research was to analyze the relation of the genetic polymorphisms frequently expressed by antigen-presenting cells, erythrocytes and malaria susceptibility/resistance with the human malaria infection cases. the sample used consisted of 23 plasmodium vivax (pv)- and p. falciparum (pf)-infected patients, and 21 healthy individuals as a control group, from the baixo amazonas population in pará, brazil. the asp299gly polymorphisms in the toll-like receptor 4 (tlr4), and gly4 ... | 2008 | 19048480 |
| prevalence of plasmodium spp. in malaria asymptomatic african migrants assessed by nucleic acid sequence based amplification. | malaria is one of the most important infectious diseases in the world. although most cases are found distributed in the tropical regions of africa, asia, central and south americas, there is in europe a significant increase in the number of imported cases in non-endemic countries, in particular due to the higher mobility in today's society. | 2009 | 19138412 |
| malaria and water resource development: the case of gilgel-gibe hydroelectric dam in ethiopia. | ethiopia plans to increase its electricity power supply by five-fold over the next five years to fulfill the needs of its people and support the economic growth based on large hydropower dams. building large dams for hydropower generation may increase the transmission of malaria since they transform ecosystems and create new vector breeding habitats. the aim of this study was to assess the effects of gilgel-gibe hydroelectric dam in ethiopia on malaria transmission and changing levels of prevale ... | 2009 | 19178727 |
| reduced neutrophil count in people of african descent is due to a regulatory variant in the duffy antigen receptor for chemokines gene. | persistently low white blood cell count (wbc) and neutrophil count is a well-described phenomenon in persons of african ancestry, whose etiology remains unknown. we recently used admixture mapping to identify an approximately 1-megabase region on chromosome 1, where ancestry status (african or european) almost entirely accounted for the difference in wbc between african americans and european americans. to identify the specific genetic change responsible for this association, we analyzed genotyp ... | 2009 | 19180233 |
| studies on the salvador i strain of plasmodium vivax in non-human primates and anopheline mosquitoes. | a review is presented on studies conducted in new world monkeys and chimpanzees with the salvador i strain of plasmodium vivax. this isolate has been adapted to aotus and saimiri (squirrel) monkeys and developed as a model for the testing of antimalarial vaccines. after the injection of 10,000 sporozoites, the median prepatent period in s. boliviensis monkeys was 21.5 days. in 103 sporozoite-induced infections in splenectomized monkeys, the median maximum parasite count ranged from 2,139 to 202, ... | 2009 | 19190218 |
| prevalence of human malaria infection in bordering areas of east balochistan, adjoining with punjab: loralai and musakhel. | to study the prevalence of malarial infections in human population of districts loralai and musakhel areas of pakistan. | 2009 | 19288935 |
| plasmodium vivax: transmission-blocking immunity in a malaria-endemic area of colombia. | plasmodium vivax transmission-blocking activity was assessed in sera from acutely infected patients from a malaria-endemic area in colombia. we measured reduction in the number of oocysts that developed in the midguts of anopheles albimanus mosquitoes artificially fed with blood from these patients. of 88 mosquito batches that developed infections when parasites were mixed with normal ab human serum, one-third (36.4%) showed full transmission-blocking activity (>or= 90% inhibition) when mixed wi ... | 2005 | 16291765 |
| the decline of malaria in finland--the impact of the vector and social variables. | malaria was prevalent in finland in the 18th century. it declined slowly without deliberate counter-measures and the last indigenous case was reported in 1954. in the present analysis of indigenous malaria in finland, an effort was made to construct a data set on annual malaria cases of maximum temporal length to be able to evaluate the significance of different factors assumed to affect malaria trends. | 2009 | 19422702 |
| structure of lactate dehydrogenase from plasmodium vivax: complexes with nadh and apadh. | malaria caused by plasmodium vivax is a major cause of global morbidity and, in rare cases, mortality. lactate dehydrogenase is an essential plasmodium protein and, therefore, a potential antimalarial drug target. ideally, drugs directed against this target would be effective against both major species of plasmodium, p. falciparum and p. vivax. in this study, the crystal structure of the lactate dehydrogenase protein from p. vivax has been solved and is compared to the equivalent structure from ... | 2005 | 16331982 |
| the glycophorin c n-linked glycan is a critical component of the ligand for the plasmodium falciparum erythrocyte receptor baebl. | plasmodium vivax uses a single member of the duffy binding-like (dbl) receptor family to invade erythrocytes and is not found in west africa where its erythrocyte ligand, the duffy blood group antigen, is missing. in contrast, plasmodium falciparum expresses four members of the dbl family, and remarkably, single-point mutations of two of these receptors (baebl and jesebl) bind to entirely different erythrocyte ligands, greatly expanding the range of erythrocytes that p. falciparum can invade. in ... | 2006 | 16461900 |
| case records of the massachusetts general hospital. weekly clinicopathological exercises. case 22-2003. a 22-year-old man with chills and fever after a stay in south america. | | 2003 | 12867613 |
| molecular basis of binding of the plasmodium falciparum receptor baebl to erythrocyte receptor glycophorin c. | plasmodium falciparum invades human erythrocytes by redundant pathways. unlike plasmodium vivax that has one duffy binding-like (dbl) receptor, p. falciparum has four members of the dbl receptor family. furthermore, one of these dbl genes, baebl, has polymorphisms at four amino acids in region ii; each polymorphism binds to a different erythrocyte receptor. one baebl variant (vstk) binds specifically to erythrocyte glycophorin c and binds poorly to neuraminidase-treated erythrocytes. when the am ... | 2009 | 19563830 |
| conservation of structure and activity in plasmodium purine nucleoside phosphorylases. | purine nucleoside phosphorylase (pnp) is central to purine salvage mechanisms in plasmodium parasites, the causative agents of malaria. most human malaria results from infection either by plasmodium falciparum (pf), the deadliest form of the parasite, or by the widespread plasmodium vivax (pv). whereas the pnp enzyme from pf has previously been studied in detail, despite the prevalence of pv little is known about many of the key metabolic enzymes from this parasite, including pvpnp. | 2009 | 19575810 |
| implementation of a novel pcr based method for detecting malaria parasites from naturally infected mosquitoes in papua new guinea. | detection of plasmodium species in mosquitoes is important for designing vector control studies. however, most of the pcr-based detection methods show some potential limitations. the objective of this study was to introduce an effective pcr-based method for detecting plasmodium vivax and plasmodium falciparum from the field-caught mosquitoes of papua new guinea. | 2009 | 19646275 |
| report of a consultation on the optimization of clinical challenge trials for evaluation of candidate blood stage malaria vaccines, 18-19 march 2009, bethesda, md, usa. | development and optimization of first generation malaria vaccine candidates has been facilitated by the existence of a well-established plasmodium falciparum clinical challenge model in which infectious sporozoites are administered to human subjects via mosquito bite. while ideal for testing pre-erythrocytic stage vaccines, some researchers believe that the sporozoite challenge model is less appropriate for testing blood stage vaccines. here we report a consultation, co-sponsored by path mvi, us ... | 2009 | 19654061 |
| the origin and age of plasmodium vivax. | the evolutionary history of plasmodium vivax has recently been addressed in terms of its origin as a parasite of humans and the age of extant populations. the consensus is that p. vivax originated as a result of a host switch from a non-human primate to hominids and that the extant populations did not originate as recently as previously proposed. here, we show that, in a comparison of parasite isolates from across the world, asian populations of p. vivax are the oldest. we discuss how this resul ... | 2006 | 17035086 |
| plasmodium vivax dbp binding to aotus nancymaae erythrocytes is duffy antigen dependent. | plasmodium vivax is the second leading cause of malaria worldwide. invasion of human erythrocytes by p. vivax merozoites is dependent upon the interaction between the parasite duffy binding protein (pvdbp) and the erythrocyte duffy antigen receptor. therefore, disruption of this vital interaction is an attractive target for therapeutic intervention. although aotus nancymaae is a commonly used primate model for human p. vivax infections, it has not been confirmed that the interaction between ao. ... | 2010 | 19799492 |
| malaria entomological inoculation rates in gold mining areas of southern venezuela. | a longitudinal study of malaria vectors aiming to describe the intensity of transmission was carried out in five villages of southern venezuela between january 1999-april 2000. the man-biting, sporozoite and entomological inoculation rates (eir) were calculated based on 121 all-night collections of anophelines landing on humans, cdc light traps and ultra violet up-draft traps. a total of 6,027 female mosquitoes representing seven species were collected. the most abundant species were anopheles m ... | 2009 | 19820839 |
| kir3dl1/s1 genotypes and kir2ds4 allelic variants in the ab kir genotypes are associated with plasmodium-positive individuals in malaria infection. | the importance of innate immunity in malaria has been suggested for early protection from maturation and multiplication of plasmodium parasites injected via infected mosquitoes. in this study, the killer cell immunoglobulin-like receptor (kir) genes in innate immunity were investigated for an association with malaria in the comparison between plasmodium-positive and plasmodium-negative melanesian individuals in the solomon islands, one of the most hyperendemic malaria regions in the world. the h ... | 2010 | 19859704 |
| evidence for transmission of plasmodium vivax among a duffy antigen negative population in western kenya. | we present evidence that a parasite with characteristics of plasmodium vivax is being transmitted among duffy blood group-negative inhabitants of kenya. thirty-two of 4,901 anopheles gambiae and an. funestus (0.65%) collected in nyanza province were elisa positive for the p. vivax circumsporozoite protein vk 247. all positives were found late in the rainy season, when an. funestus predominated, and disproportionately many were found at a single village. a p. vivax specific sequence of the ssu rr ... | 2006 | 17038676 |
| cloning, expression and functional activity of deoxyhypusine synthase from plasmodium vivax. | plasmodium vivax is the most widespread human malaria parasite. however, genetic information about its pathogenesis is limited at present, due to the lack of a reproducible in vitro cultivation method. sequencing of the plasmodium vivax genome suggested the presence of a homolog of deoxyhypusine synthase (dhs) from p. falciparum, the key regulatory enzyme in the first committed step of hypusine biosynthesis. dhs is involved in cell proliferation, and thus a valuable drug target for the human mal ... | 2006 | 17042947 |
| evolutionary genetic insights into plasmodium falciparum functional genes. | complex and rapidly evolving behavior of the human malaria parasite plasmodium falciparum have always been mysterious to the evolutionary biologists, as the parasite is the most virulent and now becoming the most prevalent malaria parasite species across the globe. with the availability of complete genome sequence of p. falciparum, better understanding of the genome design and evolution could be possible. we herein utilized the available information of all known functional genes from whole genom ... | 2010 | 19902252 |
| the use of transgenic plasmodium berghei expressing the plasmodium vivax antigen p25 to determine the transmission-blocking activity of sera from malaria vaccine trials. | p25 is a major surface protein of plasmodium ookinetes. antibodies against p25 prevent the formation of oocysts in the mosquito and thereby block transmission of the parasite through an endemic population. plasmodium vivax transmission-blocking vaccines based on pv25 have undergone human trials and inhibit transmission significantly. the current assay to determine transmission-blocking activity (tba) of these sera, the 'standard membrane feeding assay', is complex and can be performed by few gro ... | 2007 | 17049690 |
| host choice and human blood index of anopheles pseudopunctipennis in a village of the andean valleys of bolivia. | the human blood index (hbi, proportion of bloodmeals of a mosquito population obtained from man) is relevant to epidemiological assessment and to the modification of measures to interrupt malaria transmission since the vectorial capacity of the vector varies as the square of the hbi. anopheles pseudopunctipennis is a main malaria vector in south america. unfortunately, few data exist concerning hbi values in its range of distribution and none from bolivia where this species is considered as an i ... | 2007 | 17241459 |
| the relative numbers of male and female gametocytes in human malaria (plasmodium vivax, plasmodium falciparum and plasmodium malariae) and hoemoproteus in birds. | | 1927 | 19985510 |
| a case of symptomatic splenic infarction in vivax malaria. | splenic infarction is a rare complication in malaria cases, and is caused primarily by plasmodium falciparum. recently in south korea, only p. vivax has prevailed since 1993. although the probability that symptomatic splenic infarction may occur in vivax malaria cases is considered relatively high, there have never been any case reports describing the occurrence of symptomatic splenic infarction in cases of vivax malaria. a 34-year-old man presented with fever that had persisted for 5 days. p. v ... | 2007 | 17374979 |
| analysis of elongation factor tu (tuf a) of apicoplast from indian plasmodium vivax isolates. | the apicomplexan parasite plasmodium vivax is responsible for causing greater than 50% of human malaria cases in central and south america, southeastern asia and the indian subcontinent. the rising severity of the disease and the resistance shown by the parasite towards usual therapeutic regimen has put forth a demand for a novel drug target to combat this disease. apicoplast, an organelle of prokaryotic origin, and its circular genome are being looked upon as a potential drug target. the apicop ... | 2007 | 17602895 |
| production of erythropoietic cells in vitro for continuous culture of plasmodium vivax. | plasmodium vivax cannot be maintained in a continuous culture. to overcome this major obstacle to p. vivax research, we have developed an in vitro method to produce susceptible red blood cell (rbc) precursors from freshly isolated human cord hematopoietic stem cells (hscs), which were activated with erythropoietin to differentiate into erythroid cells. differentiation and maturation of erythroid cells were monitored using cell surface markers (cd71, cd36, gpa and fy6). duffy(+) reticulocytes app ... | 2007 | 17610880 |