selection by flow-sorting of genetically transformed, gfp-expressing blood stages of the rodent malaria parasite, plasmodium berghei.this protocol describes a methodology for the genetic transformation of the rodent malaria parasite plasmodium berghei and the subsequent selection of transformed parasites expressing green fluorescent protein (gfp) by flow-sorting. it provides methods for: transfection of the schizont stage with dna constructs that contain gfp as the selectable marker; selection of fluorescent mutants by flow-sorting; and injection of flow-sorted, gfp-expressing parasites into mice and the subsequent collection ...200617406288
impairment of the plasmodium falciparum erythrocytic cycle induced by angiotensin peptides.plasmodium falciparum causes the most serious complications of malaria and is a public health problem worldwide with over 2 million deaths each year. the erythrocyte invasion mechanisms by plasmodium sp. have been well described, however the physiological aspects involving host components in this process are still poorly understood. here, we provide evidence for the role of renin-angiotensin system (ras) components in reducing erythrocyte invasion by p. falciparum. angiotensin ii (ang ii) reduce ...201121364758
indigenous plasmodium ovale malaria in spite of the high prevalence of malaria in southeastern bangladesh, there remains a significant shortage of information regarding the presence of three of five human malaria parasites: plasmodium ovale, p. malariae, and p. knowlesi. the presence of p. ovale and p. knowlesi has previously never been reported from bangladesh. we used a genus- and species-specific nested polymerase chain reaction, targeting highly conserved regions of the small subunit ribosomal rna (ssu rrna) gene, to investiga ...201020595481
hematozoa and a new haemoproteid species from cathartidae (new world vultures)in south carolina.abstract abstract: a survey of turkey vultures (cathartes aura) in south carolina revealed the presence of a novel haemoproteid. haemoproteus catharti n.sp. is described from the slides from this vulture. the new species is a thick, halteridial form with complete margins and is considered distinct from the other recognized haemoproteids from the diurnal raptors in shape, pigment number, parasite outline and host family specificity. while reviewing blood films, a series of unusual immature schizo ...201121801006
interaction between artemisinin and heme. a density functional theory study of structures and interaction energies.malaria is an infectious disease caused by the unicellular parasite plasmodium sp. currently, the malaria parasite is becoming resistant to the traditional pharmacological alternatives, which are ineffective. artemisinin is the most recent advance in the chemotherapy of malaria. since it has been proven that artemisinin may act on intracellular heme, we have undertaken a systematic study of several interactions and arrangements between artemisinin and heme. density functional theory calculations ...200818375130
antimalarial activity of betulinic acid and derivatives in vitro against plasmodium falciparum and in vivo in p. berghei-infected mice.malaria is one of the most important tropical diseases and mainly affects populations living in developing countries. reduced sensitivity of plasmodium sp. to formerly recommended antimalarial drugs places an increasing burden on malaria control programs as well as on national health systems in endemic countries. the present study aims to evaluate the antimalarial activity of betulinic acid and its derivative compounds, betulonic acid, betulinic acid acetate, betulinic acid methyl ester, and bet ...200919367418
structural modifications of quinoline-based antimalarial agents: recent developments.antimalarial drugs constitute a major part of antiprotozoal drugs and have been in practice for a long time. antimalarial agents generally belong to the class of quinoline which acts by interfering with heme metabolism. the recent increase in development of chloroquine-resistant strains of plasmodium falciparum and failure of vaccination program against malaria have fuelled the drug discovery program against this old and widespread disease. quinoline and its related derivative comprise a class o ...201021814435
plasmodium falciparum resistant to chloroquine and to pyrimethamine in comoros.we report the outcome of chloroquine treatment and the prevalence of mutations at codon 86 of the pfmdr1 gene, at codon 76 of the pfcrt gene, and at codon 108 of the pfdhfr gene in clinical isolates of plasmodium falciparum collected from 30 children under 10 years of age living in the comoros union. this in vivo study was carried out in february and march 2001 in moroni. chloroquine treatment failed in 23 children (76.6%; 95% confidence interval: 57.7 to 90.1%). subsequent genotyping showed tha ...200415638145
a systematic classification of plasmodium falciparum p-loop ntpases: structural and functional correlation.the p-loop ntpases constitute one of the largest groups of globular protein domains that play highly diverse functional roles in most of the organisms. even with the availability of nearly 300 different hidden markov models representing the p-loop ntpase superfamily, not many p-loop ntpases are known in plasmodium falciparum. a number of characteristic attributes of the genome have resulted into the lack of knowledge about this functionally diverse, but important class of proteins.200919374766
pathological rupture of the spleen in malaria: analysis of 55 cases (1958-2008).splenic rupture during acute malaria is rare but underreported. because splenic rupture occurs mostly in non-immune adults, ongoing malaria elimination efforts may paradoxically increase the proportion of plasmodium-infected patients suffering from this life-threatening complication. the pathogenesis and optimal patient management are still debated.200919411041
hematological and plasma biochemistry of the adult wild african grasscutter (thryonomys swinderianus).hematological and plasma biochemical values of wild grasscutters were evaluated to determine their potential to transmit zoonotic pathogens. three 5-ml blood samples were collected from each of 1000 grasscutters caught in the wild for hematology, biochemical, and parasitological tests. hematological and biochemical values were compared with those from captive-reared grasscutters. there are significantly (p < 0.05) higher lymphocyte, eosinophil, and basophil values for wild grasscutters compared ...200819120259
immobilization of the type xiv myosin complex in toxoplasma gondii.the substrate-dependent movement of apicomplexan parasites such as toxoplasma gondii and plasmodium sp. is driven by the interaction of a type xiv myosin with f-actin. a complex containing the myosin-a heavy chain, a myosin light chain, and the accessory protein gap45 is attached to the membranes of the inner membrane complex (imc) through its tight interaction with the integral membrane glycoprotein gap50. for the interaction of this complex with f-actin to result in net parasite movement, it i ...200717538016
bacteria of the genus asaia stably associate with anopheles stephensi, an asian malarial mosquito, we show that an alpha-proteobacterium of the genus asaia is stably associated with larvae and adults of anopheles stephensi, an important mosquito vector of plasmodium vivax, a main malaria agent in asia. asaia bacteria dominate mosquito-associated microbiota, as shown by 16s rrna gene abundance, quantitative pcr, transmission electron microscopy and in situ-hybridization of 16s rrna genes. in adult mosquitoes, asaia sp. is present in high population density in the female gut and in the ma ...200717502606
regulation of cd8+ t cell responses to infection with parasitic protozoa.there are over 10,000 species of parasitic protozoa, a subset of which can cause considerable disease in humans. here we examine in detail the complex immune response generated during infection with a subset of these parasites: trypanosoma cruzi, leishmania sp., toxoplasma gondii, and plasmodium sp. while these particular species perhaps represent the most studied parasites in terms of understanding how t cells function during infection, it is clear that the lessons learned from this body of wor ...201020493842
comparison of three real-time pcr methods with blood smears and rapid diagnostic test in plasmodium sp. cases of malaria, rapid and accurate diagnosis of plasmodium sp. is essential. in this study three different quantitative, real-time pcr methods were compared with routine methods used for malaria diagnosis. a comparative study was conducted prospectively in the laboratories of montpellier and nîmes university hospitals. the methods used for routine diagnostic malaria testing consisted of microscopic examination of giemsa-stained blood smears and rapid diagnostic tests. three quantitative rea ...201019840032
annual variations in the number of malaria cases related to two different patterns of anopheles darlingi transmission potential in the maroni area of french guiana.with an annual parasite incidence (api) of 132.1, in the high and moderate risks zones, the maroni area of french guiana has the second highest malaria incidence of south-america after guyana (api = 183.54) and far above brazil (api = 28.25). malaria transmission is occurring despite strong medical assistance and active vector control, based on general who recommendations. this situation is generated by two main factors that are the social and cultural characteristics of this border area, where ...201020307300
hematological parameters of ameiva ameiva (reptilia: teiidae) naturally infected with hemogregarine: confirmation of monocytosis.little is known on how hematozoan infection changes reptile hematology. the lizard ameiva ameiva is widely distributed in the americas and is infected by hematozoan parasites. previous studies on this lizard have shown that the parasite of monocytes causes a variety of ultrastructural changes in infected host cells. the present study reports that this infection does not cause any change to the erythrocytic values. however, a marked increase in the number of leukocytes (especially monocytes) was ...201020409641
stronger activity of human immunodeficiency virus type 1 protease inhibitors against clinical isolates of plasmodium vivax than against those of p. falciparum.recent studies using laboratory clones have demonstrated that several antiretroviral protease inhibitors (pis) inhibit the growth of plasmodium falciparum at concentrations that may be of clinical significance, especially during human immunodeficiency virus type 1 (hiv-1) and malaria coinfection. using clinical isolates, we now demonstrate the in vitro effectiveness of two hiv-1 aspartic pis, saquinavir (sqv) and ritonavir (rtv), against p. vivax (n = 30) and p. falciparum (n = 20) from populati ...200818443130
regulation of gene expression in protozoa parasites.infections with protozoa parasites are associated with high burdens of morbidity and mortality across the developing world. despite extensive efforts to control the transmission of these parasites, the spread of populations resistant to drugs and the lack of effective vaccines against them contribute to their persistence as major public health problems. parasites should perform a strict control on the expression of genes involved in their pathogenicity, differentiation, immune evasion, or drug r ...201020204171
the antimalarial trioxaquine du1301 alkylates heme in malaria-infected mice.the in vivo alkylation of heme by the antimalarial trioxaquine du1301 afforded covalent heme-drug adducts that were detected in the spleens of plasmodium sp.-infected mice. this result indicates that the alkylation capacities of trioxaquines in mammals infected with plasmodium strains are similar to that of artemisinin, a natural antimalarial trioxane-containing drug.200818559651
blood parasites in wood storks (mycteria americana) from the southeastern united states.wood storks (mycteria americana) are endangered throughout their breeding range in the united states. because of this, researchers have had little opportunity to thoroughly examine the continental wood stork population for endoparasites. the blood protozoan haemoproteus crumenium has been identified from several populations of wood storks in north america. however, there have been no reports of wood storks being infected with species of plasmodium or leucocytozoon. during 2003, 42 nestling wood ...200818576809
natural plasmodium infections in brazilian wild monkeys: reservoirs for human infections?four hundred and forty-eight samples of total blood from wild monkeys living in areas where human autochthonous malaria cases have been reported were screened for the presence of plasmodium using microscopy and pcr analysis. samples came from the following distinct ecological areas of brazil: atlantic forest (n=140), semideciduous atlantic forest (n=257) and cerrado (a savannah-like habitat) (n=51). thick and thin blood smears of each specimen were examined and plasmodium infection was screened ...200818620330
characterization of a conserved rhoptry-associated leucine zipper-like protein in the malaria parasite plasmodium of the key processes in the pathobiology of the malaria parasite is the invasion and subsequent modification of the human erythrocyte. in this complex process, an unknown number of parasite proteins are involved, some of which are leading vaccine candidates. the majority of the proteins that play pivotal roles in invasion are either stored in the apical secretory organelles or located on the surface of the merozoite, the invasive stage of the parasite. using transcriptional and structural fe ...200818174339
carotenoid-based bill colour is an integrative signal of multiple parasite infection in the study of parasite-mediated sexual selection, there has been controversial evidence for the prediction that brighter males should have fewer parasites. most of these studies have focused on one parasite species. our aim was to investigate the expression of carotenoid-based coloured signals in relation to patterns of multiple parasite infections, to determine whether colour reflects parasite load of all parasite species, or whether different relationships might be found when looking at each ...201020845023
synthesis, antimalarial activity, and intracellular targets of mefas, a new hybrid compound derived from mefloquine and artesunate.a new synthetic antimalarial drug, a salt derived from two antimalarial molecules, mefloquine (mq) and artesunate (as), here named mefas, has been tested for its pharmacological activity. combinations of as plus mq hydrochloride are currently being used in areas with drug-resistant plasmodium falciparum parasites; although as clears parasitemia in shorter time periods than any other antimalarial drug, it does not cure infected patients; in addition, mq causes side effects and is rather expensive ...200818710907
targeting the plasmepsin 4 orthologs of plasmodium sp. with "double drug" inhibitors.plasmepsin 4 (pm4) is a digestive vacuole enzyme found in all plasmodium species examined to date. while p. falciparum has three additional aspartic proteinases in its digestive vacuole in addition to plasmepsin 4, other plasmodium species have only pm4 in their digestive vacuole. therefore, pm4 may be a good target for the development of an antimalarial drug. this study presents data obtained with pm4s from several plasmodium species. low nanomolar k(i) values have been observed for all pm4s st ...200818991760
comparative evaluation of two rapid field tests for malaria diagnosis: partec rapid malaria test(r) and binax now(r) malaria rapid diagnostic test.abstract: background: about 90% of all malaria deaths in sub-saharan africa occur in children under five years. fast and reliable diagnosis of malaria requires confirmation of the presence of malaria parasites in the blood of patients with fever or history suggestive of malaria; hence a prompt and accurate diagnosis of malaria is the key to effective disease management. confirmation of malaria infection requires the availability of a rapid, sensitive, and specific testing at an affordable cost. ...201121605401
nephrotic syndrome and unrecognized plasmodium malariae infection in a us navy sailor 14 years after departing nigeria.a 34-year-old nigerian man presented with nephrotic syndrome. renal biopsy revealed chronic membranous glomerulopathy with focal segmental sclerosis. blood giemsa smear contained rare plasmodium sp. trophozoites and small subunit ribosomal rna polymerase chain reaction amplification confirmed the presence of plasmodium malariae. this case highlights the importance of obtaining even remote travel histories from ill immigrants and considering occult quartan malaria in patients from endemic locatio ...201121722243
african monkeys are infected by plasmodium falciparum nonhuman primate-specific strains.recent molecular exploration of the plasmodium species circulating in great apes in africa has revealed the existence of a large and previously unknown diversity of plasmodium. for instance, gorillas were found to be infected by parasites closely related to plasmodium falciparum, suggesting that the human malignant malaria agent may have arisen after a transfer from gorillas. although this scenario is likely in light of the data collected in great apes, it remained to be ascertained whether p. f ...201121730135
avian haemosporidian parasites infection in wild birds inhabiting minami-daito island of the northwest pacific, japan.haemosporidian parasites infection among wild birds inhabiting minami-daito island was studied. blood films from 183 birds representing 4 species of 4 families were examined microscopically. avian haemosporidian parasites were detected in 3 species with an overall prevalence of 59.6%. none of the 30 daito scops owls (otus scops interpositus) examined were infected. either haemoproteus sp. or plasmodium sp. infection was found in 14 of 31 (45.2%) borodino islands white-eyes (zosterops japonicus d ...200818525175
asymptomatic carriage of malaria parasites in blood donors in yaoundébackground: malaria can be transmitted through blood transfusion, but there is paucity of data concerning transfusion-transmitted malaria in cameroun. objective: to determine prevalence of malaria infection and association with epidemiological and clinical data obtained from donors' responses. methods: microscopic examination of stained thick and thin blood smears for the detection, quantification and specification of plasmodium sp was performed on 493 blood donors in two main hospitals in yaoun ...201122141368
production of amorphadiene in yeast, and its conversion to dihydroartemisinic acid, precursor to the antimalarial agent artemisinin.malaria, caused by plasmodium sp, results in almost one million deaths and over 200 million new infections annually. the world health organization has recommended that artemisinin-based combination therapies be used for treatment of malaria. artemisinin is a sesquiterpene lactone isolated from the plant artemisia annua. however, the supply and price of artemisinin fluctuate greatly, and an alternative production method would be valuable to increase availability. we describe progress toward the g ...201222247290
detection of plasmodium sp. in the present study, we have microscopically and molecularly surveyed blood samples from 11 captive capybaras (hydrochaeris hydrochaeris) from the sanctuary zoo for plasmodium sp. infection. one animal presented positive on blood smear by light microscopy. polymerase chain reaction was carried out accordingly using a nested genus-specific protocol, which uses oligonucleotides from conserved sequences flanking a variable sequence region in the small subunit ribosomal rna (ssrrna) of all plasmodi ...200919411142
genetic diversity and population structure of plasmodium falciparum in thailand, a low transmission country.the population structure of the causative agents of human malaria, plasmodium sp., including the most serious agent plasmodium falciparum, depends on the local epidemiological and demographic situations, such as the incidence of infected people, the vector transmission intensity and migration of inhabitants (i.e. exchange between sites). analysing the structure of p. falciparum populations at a large scale, such as continents, or with markers that are subject to non-neutral selection, can lead t ...200919602241
bayesian geostatistical modelling of malaria and lymphatic filariasis infections in uganda: predictors of risk and geographical patterns of uganda, malaria and lymphatic filariasis (causative agent wuchereria bancrofti) are transmitted by the same vector species of anopheles mosquitoes, and thus are likely to share common environmental risk factors and overlap in geographical space. in a comprehensive nationwide survey in 2000-2003 the geographical distribution of w. bancrofti was assessed by screening school-aged children for circulating filarial antigens (cfa). concurrently, blood smears were examined for malaria parasites. in ...201121989409
congenital parasitic infections: a review.this review defines the concepts of maternal-fetal (congenital) and vertical transmissions (mother-to-child) of pathogens and specifies the human parasites susceptible to be congenitally transferred. it highlights the epidemiological features of this transmission mode for the three main congenital parasitic infections due to toxoplasma gondii, trypanosoma cruzi and plasmodium sp. information on the possible maternal-fetal routes of transmission, the placental responses to infection and timing of ...201222085916
intestinal and haematic parasitism in the birds of the almuñecar (granada, spain) ornithological garden.birds from the almuñecar ornithological garden (granada, spain) were surveyed from june 2006 to may 2007 to establish programmes to prevent, control, and treat intestinal and haematic parasites. a total of 984 faecal samples and 41 samples of blood were collected from psittacidae, cacatuidae, phasianidae, and anatidae. one or more intestinal parasites were identified in 51.6% of the samples. blood parasites were found in 26.8% of the birds examined. the most frequent pathogenic endoparasites wer ...200919682800
the parasitic communities of the rock pigeon columba livia from iraq: component and importance.the main objectives of the present study were to investigate the rock pigeon parasitic communities from iraq as well as reporting on the prevalence and intensity of various infections from both sexes.201223339946
molecular screening of plasmodium sp. asymptomatic carriers among transfusion centers from brazilian amazon region.the transmission of malaria in brazil is heterogeneous throughout endemic areas and the presence of asymptomatic plasmodium sp. carriers (apcs) in the brazilian amazon has already been demonstrated. malaria screening in blood banks is based on the selection of donors in respect to possible risks associated with travel or residence, clinical evidence and/or inaccurate diagnostic methods thereby increasing the probability of transfusion-transmitted infection. we evaluated the frequency of apcs in ...200717384812
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