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Find video protocols related to scientific articles indexed in Pubmed.
Influence of age on the haemoglobin concentration of malaria-infected patients in a reference centre in the Brazilian Amazon.
Mem. Inst. Oswaldo Cruz
PUBLISHED: 08-19-2014
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Anaemia is amongst the major complications of malaria, a major public health problem in the Amazon Region in Latin America. We examined the haemoglobin (Hb) concentrations of malaria-infected patients and compared it to that of malaria-negative febrile patients and afebrile controls. The haematological parameters of febrile patients who had a thick-blood-smear performed at an infectious diseases reference centre of the Brazilian Amazon between December 2009-January 2012 were retrieved together with clinical data. An afebrile community control group was composed from a survey performed in a malaria-endemic area. Hb concentrations and anaemia prevalence were analysed according to clinical-epidemiological status and demographic characteristics. In total, 7,831 observations were included. Patients with Plasmodium falciparum infection had lower mean Hb concentrations (10.5 g/dL) followed by P. vivax-infected individuals (12.4 g/dL), community controls (12.8 g/dL) and malaria-negative febrile patients (13.1 g/dL) (p < 0.001). Age, gender and clinical-epidemiological status were strong independent predictors for both outcomes. Amongst malaria-infected individuals, women in the reproductive age had considerably lower Hb concentrations. In this moderate transmission intensity setting, both vivax and falciparum malaria are associated with reduced Hb concentrations and risk of anaemia throughout a wide age range.
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Slow clearance of Plasmodium vivax with chloroquine amongst children younger than six months of age in the Brazilian Amazon.
Mem. Inst. Oswaldo Cruz
PUBLISHED: 06-02-2014
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Plasmodium vivax is the most widespread parasite causing malaria, being especially prevalent in the Americas and Southeast Asia. Children are one of the most affected populations, especially in highly endemic areas. However, there are few studies evaluating the therapeutic response of infants with vivax malaria. This study retrospectively evaluated the parasitaemia clearance in children diagnosed with vivax malaria during the first five days of exclusive treatment with chloroquine (CQ). Infants aged less than six months old had a significantly slower parasitaemia clearance time compared to the group of infants and children between six months and 12 years old (Kaplan-Meier survival analysis; Wilcoxon test; p = 0.004). The impaired clearance of parasitaemia in younger children with vivax malaria is shown for the first time in Latin America. It is speculated that CQ pharmacokinetics in young children with vivax malaria is distinct, but this specific population may also allow the detection of CQ-resistant parasites during follow-up, due to the lack of previous immunity.
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High frequency of diabetes and impaired fasting glucose in patients with glucose-6-phosphate dehydrogenase deficiency in the Western brazilian Amazon.
Am. J. Trop. Med. Hyg.
PUBLISHED: 05-27-2014
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Glucose-6-phosphate dehydrogenase (G6PD) deficiency is one of the most common human genetic abnormalities, and it has a significant prevalence in the male population (X chromosome linked). The purpose of this study was to estimate the frequency of impaired fasting glucose and diabetes among G6PD-deficient persons in Manaus, Brazil, an area in the Western Brazilian Amazon to which malaria is endemic. Glucose-6-phosphate dehydrogenase-deficient males had more impaired fasting glucose and diabetes. This feature could be used as a screening tool for G6PD-deficient persons who are unable to use primaquine for the radical cure of Plasmodium vivax malaria.
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Plasmodium vivax Chloroquine Resistance and Anemia in the Western Brazilian Amazon.
Antimicrob. Agents Chemother.
PUBLISHED: 10-28-2013
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Data on chloroquine (CQ)-resistant Plasmodium vivax in Latin America is limited, even with the current research efforts to sustain an efficient malaria control program in all these countries where P. vivax is endemic and where malaria still is a major public health issue. This study estimated in vivo CQ resistance in patients with uncomplicated P. vivax malaria, with use of CQ and primaquine simultaneously, in the Brazilian Amazon. Of a total of 135 enrolled subjects who accomplished the 28-day follow-up, parasitological failure was observed in 7 (5.2%) patients, in whom plasma CQ and desethylchloroquine (DCQ) concentrations were above 100 ng/dl. Univariate analysis showed that previous exposure to malaria and a higher initial mean parasitemia were associated with resistance but not with age or gender. In the multivariate analysis, only high initial parasitemia remained significant. Hemoglobin levels were similar at the beginning of the follow-up and were not associated with parasitemia. However, at day 3 and day 7, hemoglobin levels were significantly lower in patients presenting CQ resistance. The P. vivax dhfr (pvdhfr), pvmrp1, pvmdr1, and pvdhps gene mutations were not related to resistance in this small sample. P. vivax CQ resistance is already a problem in the Brazilian Amazon, which could be to some extent associated with the simultaneous report of anemia triggered by this parasite, a common complication of the disease in most of the areas of endemicity.
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Use of a colorimetric (DELI) test for the evaluation of chemoresistance of Plasmodium falciparum and Plasmodium vivax to commonly used anti-plasmodial drugs in the Brazilian Amazon.
Malar. J.
PUBLISHED: 05-23-2013
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The emergence and spread of Plasmodium falciparum and Plasmodium vivax resistance to available anti-malarial drugs represents a major drawback in the control of malaria and its associated morbidity and mortality. The aim of this study was to evaluate the chemoresistance profile of P. falciparum and P. vivax to commonly used anti-plasmodial drugs in a malaria-endemic area in the Brazilian Amazon.
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Molecular epidemiology of ?-lactamase-producing Neisseria gonorrhoeae strains in Manaus, AM, Brazil.
Sex Transm Dis
PUBLISHED: 05-18-2013
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We report new sequence types of 14 penicillinase-producing Neisseria gonorrhoeae, isolated from sexually transmitted disease clinic attendees in Manaus, Brazil. They were characterized by WI/WII/WIII groups, susceptibility testing and Multi-Antigen Sequencing Typing/Mutilocus Sequence Typing protocols. Twelve were classified as WII/III and 2 as WI and were presented resistance to penicillin and tetracycline. New alleles for por and AroE genes and novel sequence types were identified, revealing molecular characteristics not described previously. ST1590 is the common ancestor after eBURST analysis, and these findings represent an important contribution of molecular epidemiology approach in gonococcis research in Amazonas.
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In vitro and in vivo antimalarial activity and cytotoxicity of extracts, fractions and a substance isolated from the Amazonian plant Tachia grandiflora (Gentianaceae).
Mem. Inst. Oswaldo Cruz
PUBLISHED: 03-26-2013
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Tachia sp. are used as antimalarials in the Amazon Region and in vivo antimalarial activity of a Tachia sp. has been previously reported. Tachia grandiflora Maguire and Weaver is an Amazonian antimalarial plant and herein its cytotoxicity and antimalarial activity were investigated. Spectral analysis of the tetraoxygenated xanthone decussatin and the iridoid aglyone amplexine isolated, respectively, from the chloroform fractions of root methanol and leaf ethanol extracts was performed. In vitro inhibition of the growth of Plasmodium falciparum Welch was evaluated using optical microscopy on blood smears. Crude extracts of leaves and roots were inactive in vitro. However, chloroform fractions of the root and leaf extracts [half-maximal inhibitory concentration (IC50) = 10.5 and 35.8 µg/mL, respectively] and amplexine (IC50= 7.1 µg/mL) were active in vitro. Extracts and fractions were not toxic to type MRC-5 human fibroblasts (IC50> 50 µg/mL). Water extracts of the roots of T. grandiflora administered by mouth were the most active extracts in the Peters 4-day suppression test in Plasmodium berghei-infected mice. At 500 mg/kg/day, these extracts exhibited 45-59% inhibition five to seven days after infection. T. grandiflora infusions, fractions and isolated substance have potential as antimalarials.
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In vitro chloroquine resistance for Plasmodium vivax isolates from the Western Brazilian Amazon.
Malar. J.
PUBLISHED: 03-25-2013
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Chloroquine (CQ) and primaquine (PQ) are still the drugs of choice to treat Plasmodium vivax malaria in many endemic areas, Brazil included. There is in vivo evidence for the P. vivax resistance to CQ in the Brazilian Amazon, where the increase in the proportion of P. vivax malaria parallels the increase of unusual clinical complications related to this species. In this study, in vitro CQ and mefloquine (MQ)-susceptibility of P. vivax isolates from the Western Brazilian Amazon was tested using the double-site enzyme-linked lactate dehydrogenase immunodetection (DELI) assay.
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Glucose-6-phosphate dehydrogenase deficient variants are associated with reduced susceptibility to malaria in the Brazilian Amazon.
Trans. R. Soc. Trop. Med. Hyg.
PUBLISHED: 03-10-2013
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Glucose-6-phosphate dehydrogenase deficiency (G6PDd) has been shown to protect against malaria infection and severe manifestations in African and Asia, but there is a scarcity of studies in the Americas. This study aimed to study the prevalence of G6PDd and its association with malaria occurrence in the Brazilian Amazon.
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Prevalence and risk factors associated to pruritus in Plasmodium vivax patients using chloroquine in the Brazilian Amazon.
Acta Trop.
PUBLISHED: 02-23-2013
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Chloroquine-induced pruritus has been described as a common adverse event in African patients being treated for Plasmodium falciparum malaria, and has been associated with treatment discontinuation in this setting. In Latin America, where Plasmodium vivax is the most common species causing malaria and chloroquine is still used as the first-line schizonticidal for treating this parasite infection, there are no reports on chloroquine-induced pruritus. This study aimed to estimate the frequency of pruritus and associated risk factors in P. vivax-infected patients treated with chloroquine in a reference centre in the Brazilian Amazon. In this cross-sectional study, patients who were prescribed with chloroquine for the treatment of microscopy-confirmed P. vivax infection in the past five days were actively asked about the occurrence of any level of pruritus and potential risk factors were investigated. Univariable and multivariable logistic regression was performed for the analysis of possible risk factors in two sets of patients: (1) all the patients interviewed and (2) restricted to patients with previous use of chloroquine. Among the 510 patients interviewed, 20.4% (95%CI: 16.9-23.9%) developed any level of pruritus during treatment with chloroquine. Most episodes of pruritus occurred during the first two days of treatment and the most common location was hands and feet. In multivariate analysis performed in the entire population, the only risk factors independently associated to pruritus were allergy history (adjusted odds ratio [AOR]: 1.83; 95%CI 1.02-3.31; p=0.044) and high parasitaemia (AOR: 1.96: 95%CI 1.22-3.13; p=0.005). In the analysis restricted to the 215 patients with previous use of chloroquine, previous chloroquine-induced pruritus was a strong predictor of pruritus occurrence (AOR: 11.84: 95%CI 3.15-44.47; p<0.001). Two patients (0.4%) interrupted treatment due to the severity of pruritus. Pruritus is a common adverse event in patients being treated with chloroquine for P. vivax malaria in the Brazilian Amazon. Host-parasite interaction may play a relevant role in the development of pruritus and concurs with the finding of strong association of pruritus with high parasitaemia and allergy history. Patients with previous chloroquine-induced pruritus had a high risk for developing pruritus. Due to its high frequency, this side effect cannot be neglected as it can have major implications on patients compliance to treatment hampering elimination efforts in the region.
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Low sensitivity of malaria rapid diagnostic tests stored at room temperature in the Brazilian Amazon Region.
J Infect Dev Ctries
PUBLISHED: 02-06-2013
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In remote areas of the Amazon Region, diagnosis of malaria by microscopy is practically impossible. This study aimed to evaluate the performance of two rapid diagnostic tests (RDTs) targeting different malaria antigens stored at room temperature in the Brazilian Amazon Region.
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Genotyping of two Neisseria gonorrhoeae fluroquinolone-resistant strains in the Brazilian Amazon Region.
Mem. Inst. Oswaldo Cruz
PUBLISHED: 06-06-2011
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We report two ciprofloxacin and ofloxacin-resistant Neisseria gonorrhoeae strains that were isolated from the urethral discharge of male patients at the sexually transmitted diseases outpatient clinic of the Alfredo da Matta Foundation (Manaus, state of Amazonas, Brazil). The gonococci displayed minimal inhibitory concentrations (> 32.00 µg/mL) and three mutations in the quinolone resistance-determining region (S91F and D95G in GyrA and S87R in ParC). Both isolates were genotyped using N. gonorrhoeae multi-antigen sequence typing and the analysis showed that the ST225 which represented an emerging widespread multi-resistant clone that has also been associated with reduced susceptibility to ceftriaxone. We recommend continued surveillance of this pathogen to assess the efficacy of anti-gonococcal antibiotics in Brazil.
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[HIV-1 infection after occupational accidents in the State of Amazonas: first reported case].
Rev. Soc. Bras. Med. Trop.
PUBLISHED: 02-17-2011
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The medical care of occupational accidents in Tropical Medicine Foundation Dr. Heitor Dourado (FMT-HVD), involving blood and body fluids, started routinely in 1999. The objective of this report is to emphasize the importance of the measures used for the control of accidents with biological material. This study is carried out after a detailed epidemiological investigation confirmed one case of human immunodeficiency virus (HIV) seroconversion after an occupational accident involving bodily fluids and sharp instruments.
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In vivo and in vitro antimalarial activity of 4-nerolidylcatechol.
Phytother Res
PUBLISHED: 01-03-2011
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4-Nerolidylcatechol (4-NC) isolated from Piper peltatum L. (Piperaceae) was evaluated for in vitro antiplasmodial activity against Plasmodium falciparum (cultures of both standard CQR (K1) and CQS (3D7) strains and two Amazonian field isolates) and for in vivo antimalarial activity using the Plasmodium berghei-murine model. 4-NC exhibits significant in vitro and moderate in vivo antiplasmodial activity. 4-NC administered orally and subcutaneously at doses of 200, 400 and 600?mg/kg/day suppressed the growth of P. berghei by up to 63% after four daily treatments (days 1-4). Also, 4-NC exhibited important in vitro antiplasmodial activity against both standard and field P. falciparum strains in which 50% inhibition of parasite growth (IC(50) ) was produced at concentrations of 0.05-2.11??g/mL and depended upon the parasite strain. Interestingly, healthy (non-infected) mice that received 4-NC orally presented (denatured) blood plasma which exhibited significant in vitro activity against P. falciparum. This is evidence that mouse metabolism allows 4-NC or active metabolites to enter the blood. Further chemical and pharmacological studies are necessary to confirm the potential of 4-NC as a new antimalarial prototype.
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Clinical aspects of hemolysis in patients with P. vivax malaria treated with primaquine, in the Brazilian Amazon.
Braz J Infect Dis
PUBLISHED: 10-22-2010
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This report describes the development of hemolysis in eighteen glucose-6-phosphate dehydrogenase deficient patients treated for Plasmodium vivax malaria with chloroquine and primaquine. The most frequent findings accompanying hemolysis were fever and leukocytosis, in addition to anemia requiring red blood cell transfusion, and development of acute renal failure. Hemolysis in patients using primaquine is not infrequent and contributes to the morbidity of infection caused by Plasmodium vivax.
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Severe Plasmodium vivax malaria, Brazilian Amazon.
Emerging Infect. Dis.
PUBLISHED: 09-30-2010
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We describe a case series of 17 patients hospitalized in Manaus (western Brazilian Amazon) with PCR-confirmed Plasmodium vivax infection who were treated with chloroquine and primaquine. The major complications were jaundice and severe anemia. No in vivo chloroquine resistance was detected. These data help characterize the clinical profile of severe P. vivax malaria in Latin America.
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Severe rhabdomyolysis caused by Plasmodium vivax malaria in the Brazilian Amazon.
Am. J. Trop. Med. Hyg.
PUBLISHED: 08-05-2010
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Severe rhabdomyolysis (creatine phosphokinase = 29,400 U/L) developed in a 16-year-old boy from Manaus, Brazil, after he started treatment with chloroquine for infection with Plasmodium vivax. Treatment led to myoglobinuria and acute renal failure. After hemodialysis, the patient improved and a muscle biopsy specimen showed no myophosphorylase or deaminase deficiency. This case of rhabdomyolysis associated with P. vivax infection showed no comorbidities. The pathogenesis is still unclear. Although rhabdomyolysis is generally reported as a complication of Plasmodium falciparum malaria, leading to metabolic and renal complications,1 it has been reported in a patient with P. vivax infection with myoadenylate deaminase deficiency.2 We report a case in a patient without typical muscle enzyme deficiencies in which severe rhabdomyolysis developed while the patients was being treated with chloroquine for a confirmed P. vivax infection.
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Concurrent helminthic infection protects schoolchildren with Plasmodium vivax from anemia.
PLoS ONE
PUBLISHED: 04-15-2010
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Plasmodium vivax is responsible for a significant portion of malaria cases worldwide, especially in Asia and Latin America, where geo-helminthiasis have a high prevalence. Impact of the interaction between vivax malaria and intestinal helminthes has been poorly explored. The objective of this study was to evaluate the influence of intestinal helminthiasis on the concentration of hemoglobin in children with Plasmodium vivax malaria in rural areas in the municipality of Careiro, in the Western Brazilian Amazon.
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Geographic structuring of the Plasmodium falciparum sarco(endo)plasmic reticulum Ca2+ ATPase (PfSERCA) gene diversity.
PLoS ONE
PUBLISHED: 01-22-2010
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Artemisinin, a thapsigargin-like sesquiterpene has been shown to inhibit the Plasmodium falciparum sarco/endoplasmic reticulum calcium-ATPase PfSERCA. To collect baseline pfserca sequence information before field deployment of Artemisinin-based Combination therapies that may select mutant parasites, we conducted a sequence analysis of 100 isolates from multiple sites in Africa, Asia and South America. Coding sequence diversity was large, with 29 mutated codons, including 32 SNPs (average of one SNP/115 bp), of which 19 were novel mutations. Most SNP detected in this study were clustered within a region in the cytosolic head of the protein. The PfSERCA functional domains were very well conserved, with non synonymous mutations located outside the functional domains, except for the S769N mutation associated in French Guiana with elevated IC(50) for artemether. The S769N mutation is located close to the hinge of the headpiece, which in other species modulates calcium affinity and in consequence efficacy of inhibitors, possibly linking calcium homeostasis to drug resistance. Genetic diversity was highest in Senegal, Brazil and French Guiana, and few mutations were identified in Asia. Population genetic analysis was conducted for a partial fragment of the gene encompassing nucleotide coordinates 87-2862 (unambiguous sequence available for 96 isolates). This supported a geographic clustering, with a separation between Old and New World samples and one dominant ancestral haplotype. Genetic drift alone cannot explain the observed polymorphism, suggesting that other evolutionary mechanisms are operating. One possible contributor could be the frequency of haemoglobinopathies that are associated with calcium dysregulation in the erythrocyte.
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Sera of patients with systemic lupus erythematosus react with plasmodial antigens and can inhibit the in vitro growth of Plasmodium falciparum.
Autoimmunity
PUBLISHED: 08-07-2009
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The acquisition of protective immunity in malaria is a slow process during which autoantibodies are produced. The present work aimed at studying a possible interference of autoimmune responses on malaria immune protection. This was done by investigating the presence of autoantibodies in the sera of malarious patients, by searching for reactivity of autoantibodies from autoimmune patients against plasmodial antigens, and by studying the effect of such antibodies on the in vitro growth of Plasmodium falciparum. Sera from systemic lupus erythematosus (SLE) and malaria patients were tested against autologous and plasmodial antigens. Out of the 109 SLE sera tested, 48 (44%) reacted against the parasite. In addition, 26 (47%) out of 55 randomly selected sera, mainly those containing anti-DNA and antinuclear autoantibodies, were able to inhibit parasite growth to some extent. Conversely, a high frequency (81%) of sera of malaria patients exhibited reactivity against autoantigens. The results show that patients with autoimmune processes can produce antibodies that recognize plasmodial antigens in the absence of plasmodial infection, that malaria patients can produce autoantibodies, that SLE sera can inhibit plasmodial growth in vitro, and that the presence of anti-DNA and antinuclear antibodies may be important in such anti-plasmodial activity. It is concluded that autoimmune responses may have influence on the protective immunity against malaria.
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Analysis of single-nucleotide polymorphisms in the crt-o and mdr1 genes of Plasmodium vivax among chloroquine-resistant isolates from the Brazilian Amazon region.
Antimicrob. Agents Chemother.
PUBLISHED: 05-18-2009
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Plasmodium vivax parasites with chloroquine resistance (CQR) are already circulating in the Brazilian Amazon. Complete single-nucleotide polymorphism (SNP) analyses of coding and noncoding sequences of the pvmdr1 and pvcrt-o genes revealed no associations with CQR, even if some mutations had not been randomly selected. In addition, striking differences in the topologies and numbers of SNPs in these transporter genes between P. vivax and P. falciparum reinforce the idea that mechanisms other than mutations may explain this virulent phenotype in P. vivax.
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Glucose-6-phosphate dehydrogenase deficiency in an endemic area for malaria in Manaus: a cross-sectional survey in the Brazilian Amazon.
PLoS ONE
PUBLISHED: 03-12-2009
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There is a paucity of information regarding glucose-6-phosphate dehydrogenase (G6PD) deficiency in endemic areas for malaria in Latin America.
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[Algid malaria: a syndromic diagnosis].
Rev. Soc. Bras. Med. Trop.
PUBLISHED: 01-19-2009
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Two patients with malaria due to Plasmodium falciparum who progressed to shock syndrome are reported. They received hemodynamic support in an intensive care unit without using antibiotics and presented improvements. Algid malaria should be a syndromic diagnosis of varying etiology (dehydration, bacterial infection, bleeding and/or adrenal insufficiency).
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Comparative hematologic analysis of uncomplicated malaria in uniquely different regions of unstable transmission in Brazil and Colombia.
Am. J. Trop. Med. Hyg.
PUBLISHED: 01-15-2009
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Information on malaria-associated anemia in adult patients is scarce in South American populations. From 2004 to 2006, malaria patients 18 to 45 years of age were recruited in a descriptive cross-sectional study from two different towns: Manaus, in the Brazilian Amazon (120 patients) where Plasmodium falciparum incidence is lower ( approximately 20%), and in Tumaco on the Colombian Pacific Coast (126 patients) where P. falciparum incidence is higher ( approximately 90%). Relationships between hematologic parameters and independent variables were explored using cross-tabulations and multiple linear regression analyses. We found an inverse relationship of hemoglobin (Hb) levels with days of illness in both sites. In Manaus but not in Tumaco, red cell distribution width (RDW) was related to asexual parasitemia. Reticulocytes were higher in Plasmodium vivax infection in Tumaco. Only in Tumaco, two patients with P. falciparum infection presented with severe anemia (Hb < 7 g/dL). Etiologic factors associated with hematologic changes in malaria seem to be multifactorial. More studies are needed to clarify the anemia determinants in uncomplicated malaria in South America, where malaria transmission is mostly unstable.
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Response to the complete hepatitis B vaccine regimen in infants under 12 months of age: a case series.
Braz J Infect Dis
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Describing rates of seroconversion and its associated factors in a series of Brazilian infants following the final dose of the vaccine at 6 months of age.
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In vitro susceptibility of Plasmodium falciparum Welch field isolates to infusions prepared from Artemisia annua L. cultivated in the Brazilian Amazon.
Mem. Inst. Oswaldo Cruz
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Artemisinin is the active antimalarial compound obtained from the leaves of Artemisia annua L. Artemisinin, and its semi-synthetic derivatives, are the main drugs used to treat multi-drug-resistant Plasmodium falciparum (one of the human malaria parasite species). The in vitro susceptibility of P. falciparum K1 and 3d7 strains and field isolates from the state of Amazonas, Brazil, to A. annua infusions (5 g dry leaves in 1 L of boiling water) and the drug standards chloroquine, quinine and artemisinin were evaluated. The A. annua used was cultivated in three Amazon ecosystems (várzea, terra preta de índio and terra firme) and in the city of Paulínia, state of São Paulo, Brazil. Artemisinin levels in the A. annua leaves used were 0.90-1.13% (m/m). The concentration of artemisinin in the infusions was 40-46 mg/L. Field P. falciparum isolates were resistant to chloroquine and sensitive to quinine and artemisinin. The average 50% inhibition concentration values for A. annua infusions against field isolates were 0.11-0.14 ?L/mL (these infusions exhibited artemisinin concentrations of 4.7-5.6 ng/mL) and were active in vitro against P. falciparum due to their artemisinin concentration. No synergistic effect was observed for artemisinin in the infusions.
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Pfatp6 molecular profile of Plasmodium falciparum isolates in the western Brazilian Amazon.
Malar. J.
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Anti-malarial drug resistance has emerged as one of the biggest challenges confronting the worldwide effort to control malaria. The appearance of chloroquine and multi-drug resistance had devastating effects on therapeutic efficacy of former first-line agents. Artemisinin has proven to be an excellent therapeutic alternative to fill the void in chemotherapeutic options left by resistance mechanisms. At the time of introduction, no resistance to artemisinins had been recorded, and artemisinins demonstrated excellent parasite reduction rates. In an attempt to protect artemisinin efficacy, the World Health Organization (WHO) made artemisinin-based combination therapy (ACT) its official first-line treatment recommendation for uncomplicated Plasmodium falciparum in 2006. In Brazil, artemether/lumefantrine became the Brazilian Malaria Control Programmes official treatment recommendation in 2007. The sarco/endoplasmic reticulum Ca2+ - ATPase ortholog of P. falciparum (pfatp6) has been suggested as one of the targets of artemisinins. Consequently, pfatp6 gene polymorphisms are being investigated as markers of artemisinin resistance elsewhere. The goal of this work was to describe the molecular profile of pfatp6 in P. falciparum isolates from different localities in the Amazonas State.
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Understanding the clinical spectrum of complicated Plasmodium vivax malaria: a systematic review on the contributions of the Brazilian literature.
Malar. J.
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The resurgence of the malaria eradication agenda and the increasing number of severe manifestation reports has contributed to a renewed interested in the Plasmodium vivax infection. It is the most geographically widespread parasite causing human malaria, with around 2.85 billion people living under risk of infection. The Brazilian Amazon region reports more than 50% of the malaria cases in Latin America and since 1990 there is a marked predominance of this species, responsible for 85% of cases in 2009. However, only a few complicated cases of P. vivax have been reported from this region. A systematic review of the Brazilian indexed and non-indexed literature on complicated cases of vivax malaria was performed including published articles, masters dissertations, doctoral theses and national congresses abstracts. The following information was retrieved: patient characteristics (demographic, presence of co-morbidities and, whenever possible, associated genetic disorders); description of each major clinical manifestation. As a result, 27 articles, 28 abstracts from scientific events annals and 13 theses/dissertations were found, only after 1987. Most of the reported information was described in small case series and case reports of patients from all the Amazonian states, and also in travellers from Brazilian non-endemic areas. The more relevant clinical complications were anaemia, thrombocytopaenia, jaundice and acute respiratory distress syndrome, present in all age groups, in addition to other more rare clinical pictures. Complications in pregnant women were also reported. Acute and chronic co-morbidities were frequent, however death was occasional. Clinical atypical cases of malaria are more frequent than published in the indexed literature, probably due to a publication bias. In the Brazilian Amazon (considered to be a low to moderate intensity area of transmission), clinical data are in accordance with the recent findings of severity described in diverse P. vivax endemic areas (especially anaemia in Southeast Asia), however in this region both children and adults are affected. Finally, gaps of knowledge and areas for future research are opportunely pointed out.
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