| acquired immune responses to the n- and c-terminal regions of plasmodium vivax merozoite surface protein 1 in individuals exposed to malaria. | in this study, we evaluated the naturally acquired immune response to plasmodium vivax merozoite surface protein 1 (pvmsp1) in individuals with recent clinical episodes of malaria from the state of para, brazil. ten recombinant proteins representing the first 682 amino acids (aa) of the n-terminal region and one representing the final 111 aa of the c-terminal region were expressed in escherichia coli as glutathione s-transferase fusion proteins. both of these regions have been suggested as candi ... | 1997 | 9125537 |
| correlation between plasmodium vivax variants in belém, pará state, brazil and symptoms and clearance of parasitaemia. | the aim of this study was to determine how different types of p. vivax affect clinical symptoms and parasitaemia clearance. blood was collected from individuals from pará state, brazil. the patients were treated as chloroquine plus primaquine. p. vivax were typed daily till d7 and again on d30. now we can confirm a previously reported correlation between p. vivax genotype and response to chloroquine. clinical symptoms do not allow for objective identification of different p. vivax types in the b ... | 2003 | 14499040 |
| malaria vectors, epidemiology, and the re-emergence of anopheles darlingi in belém, pará, brazil. | an evaluation of malaria transmission and epidemiology in the amazonian city of belém over the last 70 years shows that (1) anopheles darlingi, reported to be eradicated in 1968, reappeared in the mid 1990s, with a marked increase in abundance between 1997 to 1999 in two of three districts sampled; (2) an. darlingi and an. aquasalis are each implicated in current malaria transmission in different districts of the city; (3) mosquito species diversity (in anopheles subgenus nyssorhynchus) has incr ... | 2003 | 14680100 |
| molecular epidemiology of plasmodium vivax in the state of amazonas, brazil. | over the past 2 decades, the amazon region of brazil has experienced reemergence of plasmodium vivax malaria, with reported occurrence of severe disease. the frequency and manifestations of this severe disease are unlike previous clinical experience. the hypothesis has been raised that the occurrence of severe disease may relate to the emergence of a variant form of the parasite. to test this hypothesis, we conducted a retrospective cohort study of p. vivax strains in the state of amazonas. we d ... | 2007 | 17397788 |
| 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 |
| malaria vectors in two indigenous reserves of the brazilian amazon. | to describe the composition, ecological and behavioral characteristics and infectivity of anopheles species in indigenous reserves of the amazon region. | 2009 | 19851633 |
| concurrent dengue and malaria in the amazon region. | the amazon region has extensive forested areas and natural ecosystems, providing favorable conditions for the existence of innumerous arboviruses. over 200 arboviruses have been isolated in brazil and about 40 are associated with human disease. four out of 40 are considered to be of public health importance in brazil: dengue viruses (1-4), oropouche, mayaro and yellow fever. along with these viruses, about 98% of the malaria cases are restricted to the legal amazon region. | 2010 | 21085859 |
| frequency of the hfe c282y and h63d polymorphisms in brazilian malaria patients and blood donors from the amazon region. | malaria is an endemic parasitosis and its causitive agent, plasmodium, has a metabolism linked to iron supply. hfe is a gene with the polymorphisms c282y and h63d, which are associated with a progressive iron accumulation in the organism leading to a disease called hereditary hemochromatosis. the aim of the present study was to determine the allelic and genotypic frequencies of the hfe gene polymorphisms in malaria patients and blood donors from the brazilian amazon region. we screened 400 blood ... | 2008 | 18273820 |
| distribution of plasmodium vivax variants (vk210, vk247 and p. vivax-like) in three endemic areas of the amazon region of brazil and their correlation with chloroquine treatment. | the present study evaluated the glass fibre membrane (gfm)-polymerase chain reaction (pcr)-enzyme-linked immunosorbent assay (elisa) technique for genotyping the plasmodium vivax variants, to verify the distribution of p. vivax variants (vk210, vk247 and p. vivax-like) in parts of brazil and their correlation with levels of parasitaemia, previous malaria experience and clearance of parasitaemia linked to different treatment schedules. the samples were taken from individuals living in macapá, por ... | 2000 | 11127238 |
| longevity of naturally acquired antibody responses to the n- and c-terminal regions of plasmodium vivax merozoite surface protein 1. | in an earlier study, we found that individuals with patent infection had significantly higher igg antibody titers to the 19-kd c-terminal region of plasmodium vivax merozoite surface protein 1 (pvmsp1) than individuals treated for malaria 1-4 months earlier. these results suggested that the antibody levels decreased rapidly following treatment. the present study was designed to determine the persistence of antibody response to the n- and c-terminal regions of pvmsp1 after infection with p. vivax ... | 1999 | 10466961 |
| [epidemiological aspects of malaria in the state of são paulo, brazil, 1983 to 1992]. | epidemiological aspects of malaria in the state of s. paulo, brazil, based on the cases motified between 1983 and 1992 are presented. in the period 20,200 cases, of which 65.7% presented plasmodium vivax (p.v.) and 27.3% p. falciparum (p.f.), were confirmed. no differences as between the years was observed. no differences in the distribution by sex (85.4% male) or age (63.6% whit ages between 20 and 39 years) were noted. the epidemiological investigations demonstrated that in 2.0% the transmissi ... | 1994 | 7747077 |
| potential vectors of malaria and their different susceptibility to plasmodium falciparum and plasmodium vivax in northern brazil identified by immunoassay. | during the period from may 1983 to july 1985 we conducted an epidemiological study to determine potential vectors of malaria in 6 districts in the state of pará in northern brazil. the examination of random human blood smears, prepared at the time of mosquito capture, indicated overall human infection rates of 16.7% and 10.9% for plasmodium falciparum and p. vivax, respectively. two immunoassays, the immunoradiometric assay (irma) and the enzyme-linked immunosorbent assay (elisa), based on the u ... | 1986 | 3532844 |
| prevalence and level of antibodies to the circumsporozoite protein of human malaria parasites in five states of the amazon region of brazil. | the aim of this study was to determine the prevalence of malaria infection and antibodies against the repetitive epitopes of the circumsporozoite (cs) proteins of plasmodium falciparum, p. malariae, p. vivax vk210, p. vivax vk247, and p. vivax-like in individuals living in the states of rondônia, pará, mato grosso, amazonas, and acre. active malaria transmission was occurring in all studied sites, except in acre. p. falciparum was the predominant species in pará and rondônia and p. vivax in mato ... | 2007 | 17568943 |