Navegando por Assunto "Plasmodium falciparum"

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Acesso aberto (Open Access)
Atividade antiplasmodial e modelagem molecular de novas chalconas e derivados
(Universidade Federal do Pará, 2008) PEREIRA, Glaécia Aparecida do Nascimento; RIBEIRO, Cláudio Tadeu Daniel; http://lattes.cnpq.br/0814854098256062; NASCIMENTO, José Luiz Martins do; http://lattes.cnpq.br/7216249286784978
Malaria is an infection caused by Plasmodium sp. and It can be serious, if not treated precociously. It affects significant fraction of humanity and has profound health impact worldwide. It is estimated that 3.3 billion people are exposed to the risk of transmission. One of the problems of the infection is the growing emergence of parasite resistance to antimalarial drugs. In this context, studies are needed to develop new alternative chemotherapy. Many substances, such as the chalcones, have had their antiplasmodial activity proven. However, the physicochemical properties of these molecules, which are important for biological actions, are not well established. In this work, molecular modeling was performed and the antiplasmodial activity was evaluated of two chalcones (HBR1, and LH2) and four derivatives of chalcones (GH3, IV4, LCH1, and LCH3). For that, we determined the drug concentration inhibitory of 50% of the growth of P. falciparum in vitro as well as the physicochemical properties of derivatives of chalcones as HOMO, LUMO, electrostatic potential, C log P, hydration energy, polarizability and molecular volume through virtual calculations. The results of the calculated values were correlated with the biological activity in order to identify chemical parameters that can influence the antiplasmodial action. The inhibitory concentrations in 50% of the growth of P. falciparum ranged from 0,2 to 1,7 M, and these values were smaller than described them in the literature. The study of the correlation between the biological activities and the physicochemical properties showed determinating parameters for the biological activity, as LUMO, electrostatic potential, C log P and hydration energy, which may help in the selection of molecules more active against P. falciparum. Thus, these molecular properties can be used in the rational planning of new chalcones and/or derivatives with antiplasmodial activity.
Acesso aberto (Open Access)
Avaliação da atividade antiplasmódica in vitro dos óleos de Andiroba (Carapa guianensis Aubl.) e Pimenta-de-macaco (Piper aduncum L)
(Universidade Federal do Pará, 2010) MIRANDA JUNIOR, Raimundo Nonato Cardoso; DOLABELA, Maria Fâni; http://lattes.cnpq.br/0458080121943649; MAIA, José Guilherme Soares; http://lattes.cnpq.br/1034534634988402
In search of new antimalarial drugs, two typical species of the Amazon region and a fraction rich limonoids were the object of this study: Carapa guianensis Aubl. (Meliaceae), known popularly as andiroba traditionally used as an insecticide and fighting malaria, the species Piper aduncum L. (Piperaceae), known popularly as the pimento-de-macaco, used to treat inflammatory diseases and the fraction rich limonoids obtained from Carapa guianensis. Crude oil and fraction were tested in vitro using methods described by Rieckman and col. (1980) modified by Carvalho (1990) with Plasmodium falciparum clones W2 and Dd2. These studies showed that the oils had antiplasmodial activity, with a concentration of 0.82ng/mL and 8.2mg/mL andiroba oil showed an inhibition he W2 clone was 100% and Dd2 to 71% (IC50 9.4 μg/ml) after 72h of exposure respectively. For the fraction at a concentration of 3.1mg/mL, clone W2, was 100% and Dd2 to 82% (IC50 0.4 μg/ml), after 72h of exposure. The pimento-de-macaco oil overalls had a concentration of 1.30ng/mL for the W2 clone inhibition of 100% and the Dd2 to 77% after 72h of exposure to a concentration of 10.3mg/mL. The results with the chili oil overalls at a concentration of 1.30ng/ml the inhibition was 100% in clone W2 and Dd2 clone at a concentration of 10.3mg/mL, inhibition was 77% after 72h of exposure.
Acesso aberto (Open Access)
Avaliação do nível de concordância do teste imunocromatográfico OptiMAL-IT® e a gota espessa no diagnóstico da malária, no município de Mazagão-AP, Brasil
(Universidade Federal do Pará, 2007) FADUL, Danielle Scerne; COUTO, Álvaro Augusto Ribeiro D'Almeida; http://lattes.cnpq.br/3800209721205388
The precocious diagnosis and the opportune treatment of the cases of malaria is one of the main strategies for the control of the disease. Several alternatives for the traditional microscopic diagnosis were proposed in the last years, the Immunochromatographic tests that capture white antigens of the parasites of the malaria they are being proposed, as the test OptiMAL-IT® that captures the lactic desidrogenase of the Plasmodium sp.. The study had as objective the evaluation of the level of agreement between the Immunochromatographic test (OptiMAL-IT®) and the thick drop for the diagnosis of the malaria in the City of Mazagão – Amapá, Brazil. 413 individuals were analyzed with malaria sintomatology that had looked for the service of the unit of health service of the city, with age among 01-68 years. The results of the OptiMAL-IT® test were compared with the obtained results, of the same samples, through the thick drop red-faced by the Giemsa. Of the 413 patients suspicious to present malaria, 317(76.8%) were positive through GE and 311 (75.3%) were positive for TDR OptiMAL-IT®. Of the positive blades of GE, had been found 27.4% of P. falciparum and 72.6% of P. vivax . The OptiMAL-IT® test detected 27.7% of P. falciparum and 72.3% of P. vivax. The sensibility obtained with TDR for P. falciparum was of 97.7% and for P. vivax was of 98.2%, the global sensibility of TDR was of 98.1% and the global specificity for both the species was of 100%. They were found preditivos values positive and negative of 100% and 94.1%, respectively. The OptiMAL-IT® test had a high agreement with thick drop, it is specific and efficient. It can be used in the diagnosis of malaria in the situations where microscopy is not available.
Acesso aberto (Open Access)
Avaliação dos níveis extracelulares de GABA e glutamato no sistema nervoso central de camundongos infectados com Plasmodium berghuei ANKA
(Universidade Federal do Pará, 2024-11) LIMA, Renato Mateus Santos de; OLIVEIRA, Karen Renata Herculano Matos; http://lattes.cnpq.br/3032008039259369
Cerebral malaria (CM) caused by Plasmodium falciparum results in high mortality, especially in children under 5, with up to 25% of survivors experiencing neurological sequelae such as cognitive impairment and seizures. The neurochemical mechanisms behind these impairments are not well understood. This study aimed to characterize changes in the levels of the neurotransmitters glutamate (GLU) and γ-Aminobutyric acid (GABA) in the central nervous system (CNS) during experimental cerebral malaria (ECM). ECM was induced in Swiss mice with Plasmodium berghei ANKA (PbA), and the animals were monitored for parasitemia, survival, and neurological impairments using the Rapid Murine Coma and Behavior Scale (RMCBS). On the 7th day post-infection (d.p.i), blood-brain barrier (BBB) disruption was assessed using Evans Blue dye, and glial cell evaluation was performed by immunofluorescence. Results showed that PbA-infected mice began to succumb to CM by the 6th d.p.i, with 100% mortality by the 10th d.p.i. Behavioral impairments were observed from the early stages of infection. Significant BBB permeability changes and increased expression of glial activation markers were noted in infected mice. There was a marked increase in GLU levels in the brain and cerebellum on days 3, 5, and 7 post-infection. GABA levels increased on days 3 and 5, returning to control levels by day 7. These findings indicate significant neurochemical alterations in GABAergic and glutamatergic neurotransmission, accompanied by neurological and vascular impairments, suggesting their involvement in the development of neurological symptoms in CM.
Acesso aberto (Open Access)
Avaliação dos níveis séricos de cortisol e de hidroepiandrosterona em pacientes com malária por Plasmodium falciparum não-complicada
(Universidade Federal do Pará, 1997) LIBONATI, Rosana Maria Feio; MEDONÇA, Berenice Bilharinho de; http://lattes.cnpq.br/8356126875514076; SOUZA, José Maria de; http://lattes.cnpq.br/6459204248879587
The main purpuse of our study was to determine the levels of both cortisol and dehydroepiandrosterone (DHEA) in serum samples from patients suffering from Plamodium falciparum malaria. Since cortisol is potentially immunesupressive, and, conversely, DHEA is inherently immunopotentiating, we sought to assess the possible association between serum levels of these steroids and patient's clinical conditions. We enrolled to participate in this study 24 patients aged 12 to 47 years, of whom 18 were male and 6 female, suffering from uncomplicated P. falciparum malaria. All patients lived in areas of the Amazon were malaria is endemic. Half of them were found to be primo-infected, whereas the others were being reinfected by P. falciparum when recruited for this investigation. Blood samples were obtained from each patients as follows: at 20-minutes intervals during the pre-treatment phase (i. e. on day 0, D0), 24 hours after starting drug therapy (D1) and at the 8th day of follow-up (D7), when patients were asymptomatic. All patients at D7 presented with negative parasitemia. Serum levels of cortisol and DHEA were measured on D0, Dl and D7 and D0 and D7, respectively. In addition, the determination of IgG antibodies to both P. falciparum and P. vivax was performed only on D0. Our results indicated that levels of cortisol in serum samples collected on D0 were significantly higher than those of D1 and D7. High levels of cortisol on D0/D1 and significant parasitemia on D1 led us to postulated that this corticosteroid may interfere with the initial response of P. falciparum-infected patients to treatment. The cortisol levels did not correlate with the intensity of fever, duration of illness and the levels of IgG antibories to P. falciparum. These findings suggest that temperature does not interfere with the cortisol levels, and these, on the other land, do not significantly ralate to either antibody response or the duration of illness. The DHEA levels were found to be significantly more elevated on D0 than on D7, even though patients were already symptomatic for more than one day when first serum samples was taken. The progressive decrease in the DHEA levels is therefore likely to be mediated by a continuous stimulus from the hypothalamic-pituitary-adrenal (HPA) axis. Similarly to cortisol, the DHEA levels on D0 correlated significantly with D1 parasitemia. Thus, it is suggested that in cortisol levels paralels that for DHEA. Of interest, the DHEA serum levels seem to inversely correlate with the duration of illness, in spite of high levels of this steroid detected at the pre-treatment phase. A not significant correlation has been noted if cortisol and DHEA serum levels are compared with temperature. This clinical parameter, however, was found to directly interfere with the correlation that exist between both cortisol and DHEA levels. It is known that fever reflects the occasion when erythrocytes disrupt from the schizogony, with release of cytokines , which act as an acute stimulating factor for the HPA axis. It would therefore be proposed that liberation of both hormones has a commom mechanism. The lack of significant interrelationships between DHEA levels and IgG antibodies indicates that this hormone does not seem to interfere with the production of antibodies by P. falciparum infected patients.
Acesso aberto (Open Access)
Caracterização in vitro dos efeitos genotóxicos e citotóxicos da droga antimalárica artesunato em linfócitos humanos
(Universidade Federal do Pará, 2015-10-23) MOTA, Tatiane Cristina; BAHIA, Marcelo de Oliveira; http://lattes.cnpq.br/3219037174956649
Malaria is one of the most serious infectious disease in the world, with quite extensive geographic distribution in tropical areas. Its treatment is based on administration of specific drugs, as artemisinin and its derivatives: artesunate, which will be the subject of this study, and artemether. The artesunate is a semi-synthetic compound derived from artemisinin, a substance extracted from the Chinese plant Artemisia annua L. Despite the widespread use of artesunate in antimalarial therapy and the strong evidences that other antimalarials such as partenin and chloroquine present genotoxic effects in vitro; there are few studies that demonstrate artesunate genotoxic effects in human lymphocytes. In previous studies carried out in laboratory human cytogenetics, it was shown that artesunate induces cytotoxic and genotoxic effects in human lymphocytes in vitro. Despite these findings, the mechanisms of these effects have not been adequately characterized due to limitations of the techniques used. This study aimed to assess in vitro the cytotoxic and genotoxic effects of artesunate on human peripheral blood lymphocytes using assays such as FISHMN, oxidative stress and immunocytochemistry by immunofluorescence. We aimed through these tools elucidate the mechanisms responsible for the effects of artesunate in DNA of human lymphocytes. The results found in this study suggest that the artesunate induces the formation of ROS and other free radicals and that these substances are causing DNA damage in human lymphocytes in culture. Thus cells with damaged DNA, not being able to reverse this condition, activate apoptosis through the extrinsic and intrinsic pathways.
Acesso aberto (Open Access)
Correlação dos teores séricos entre mefloquina e carboximefloquina com os teores de colesterol total e frações e triglicerídeos em pacientes com malária por Plasmodium falciparum não complicada
(Universidade Federal do Pará, 2010) RIVERA, Juan Gonzalo Bardález; VIEIRA, José Luiz Fernandes; http://lattes.cnpq.br/2739079559531098
Malaria is a major cause of morbidity and mortality worldwide, with over 100 million cases and at least one million deaths annually. It is a disease prevalent in the countries of tropical and subtropical climate of the planet. In Brazil, it occurs mainly in the Amazon region where climatic conditions favor the breeding of the vector and the spread of disease. With the emergence of vector resistance to insecticides, the lack of an effective vaccine, and especially the resistance of plasmodia to antimalarial drugs available today, there has been a resurgence and spread of the disease worldwide. Among the drugs used to treat the disease stands to mefloquine, which has high lipid solubility, being associated to a specific polipetídio (apo-A1) present in high density lipoproteins (HDL). Thus, infected erythrocytes tend to bind to circulating HDL particles to obtain the lipid supply, which would favor the passage and accumulation of the drug in these. However, malaria patients showed abnormal lipid profile, such as decreased levels of cholesterol total, HDL and LDL cholesterol, elevated values of lactate dehydrogenase, and a moderate increase of triglyceride level. This study is the correlation between serum concentrations of total cholesterol, HDL, LDL and triglycerides in serum levels of mefloquine (MQ) and carboximefloquina (CMC) in patients with falciparum malaria not complicated. For this we used the biochemical determination through self-plush Cobas analyzer to determine the levels of serum cholesterol and triglycerides and high performance liquid chromatography for determination of serum levels of mefloquine and carboximefloquina. Significant difference in serum total cholesterol, and HDL and LDL, which increased over the course of clinical evaluation, which corroborates findings in the literature and there was significant difference in serum triglycerides, which decreased with clinical outcome of patients.
Acesso aberto (Open Access)
Correlação entre as concentrações sérica e eritrocitária de quinina no estado de equilíbrio em pacientes com malária por Plasmodium falciparum não complicada
(Universidade Federal do Pará, 2007) GUIMARÃES, Erika Rodrigues; VIEIRA, José Luiz Fernandes; http://lattes.cnpq.br/2739079559531098
The correlation between the serum and red blood cells concentrations of quinine was studied in children and adults with falciparum malaria uncomplicated in Cachoeira of the Piriá, in the State of Pará. The patients had received the oral scheme of quinine (3 days) + doxycyclina (5 days) + primaquine (6º day). Quinine concentration in the serum and the red blood cells samples was measured by High Performance Liquid Chromatography in the third day of treatment. The average of the serum concentration of the quinine in children with uncomplicated falciparum malaria was of 0,723 ± 0,6 μg/mL, and 0,537 ± 0,38 μg/mL for the red blood cells. And the relationship between the serum and red blood cells concentration was 1,89 ± 1,25 μg/mL, had not difference statistical significant between those concentrations. The average of the serum concentration of adult individuals was of 1,27 ± 1,12 μg/mL, and 0,63 ± 0,48 μg/mL for the red blood cells. The relationship between those concentration was of 2,27 ± 1,06 μg/mL. The results had shown that it did not have significant statistical difference between the averages of the relation of quinine levels in the serum and the red blood cells of the children and the adults.
Acesso aberto (Open Access)
Determinação de mefloquina e carboximefloquina em pacientes com malária por plasmodium falciparum no estado do Amapá
(Universidade Federal do Pará, 2008) BORGES, Larissa Maria Guimarães; VIEIRA, José Luiz Fernandes; http://lattes.cnpq.br/2739079559531098
The determination of plasmatic and erythrocyte concentrations of mefloquine (MQ) and carboxymefloquine (CMQ) were studied in children and adults with malaria by Plasmodium falciparum not complicated in the Amapa state. The adult patients received oral outline of MQ 20 mg/kg divided in two days and artesunate 4 mg/kg/day for three days. For children the dose of MQ followed the schedule recommended by the manual of malaria therapy. Concentrations of MQ and CMQ in erythrocytes were quantified by high performance liquid chromatography on the third day of treatment (D3) and plasma levels were measured in the third and second fortieth day after the institution of therapy (D3 and D42). The average concentration of MQ and CMQ in plasma of children in D3 were 1.84 ± 0.83 μg/mL and 1.44 ± 0.70 μg/mL, and in erythrocytes 5.26 ± 1.46 μg/mL and 1.18 ± 0.65 μg/mL. In D42 the plasma concentrations were 0.45 ± 0.11 μg/mL and 0.51 ± 0.10 μg/mL, respectively. The relationship between plasma and erythrocytes concentrations of MQ and CMQ were 2.86 ± 1.27 and 0.75 ± 0.26. In adults, concentrations of MQ and CMQ in plasma were 2.43 ± 1.13 μg/mL and 1.10 ± 0.38 μg/mL, and in erythrocytes 5.51 ± 1.92 μg/mL and 1.08 ± 0.35 μg/mL, respectively. The plasma concentrations in D42 were 0.54 ± 0.15 μg/mL and 0.58 ± 0.93 μg/mL, respectively. The relationship erythrocyte:plasma for MQ was 3.03 ± 1.56 and 1.12 ± 0.29 to CMQ. The correlation coefficient between plasma and erythrocytes concentrations of MQ in children was 0.035 and adults 0.0436. For CMQ the correlation coefficient in children was 0.8722 and in adults 0.5155. The higher accumulation of MQ in the red blood cells allows us to emphasize the importance of the simple diffusion for the entry of the drug in the cell because of their physical and chemical characteristics.
Acesso aberto (Open Access)
Efeito protetor da ração enriquecida com açaí (Euterpe oleracea) no quadro de malária cerebral experimental
(Universidade Federal do Pará, 2018-05-17) TORRES, Marjorie Lujan Marques; OLIVEIRA, Karen Renata Herculano Matos; http://lattes.cnpq.br/3032008039259369; BATISTA, Evander de Jesus Oliveira; http://lattes.cnpq.br/2206444845201080
Cerebral malaria (CM) is one of the most severe complications attributed to protozoal infection by Plasmodium falciparum, gaining prominence in infant mortality rates in endemic areas. It´s a complex pathogenesis and still little elucidated, being associated with cognitive, behavioral and motor changes. Aiming to broaden the knowledge about this pathology and looking for the benefits attributed to the daily consumption of antioxidants, the objective of this work is to evaluate the possible protective effect of Euterpe oleracea fruit (açaí) during evolution of experimental cerebral malaria (ECM) induced in murine model by means of inoculation of Plasmodium berghei (PbA), ANKA stain. For this, we used the Swiss line, which were inoculated intraperitoneally (i.p.) with 10⁶ of parasited erythrocytes. The animals (females and males between 4 and 6 weeks) were divided into four groups, among which Açaí and PbA+Açaí groups were maintained on a ration-exclusive diet enriched with açaí and the Control and PbA groups were given only standard ration during 22 days of experiment. To characterize the ECM framework, several parameters were evaluated such as the appearence of clinical signs, survival curve, parasitemia, body mass gain and vascular permeability. The SHIRPA protocol was used to evaluate the behavioral and locomotor changes in animals. We observed an extension of survival of the infected animals and treated with a diet enriched with acai berry, and decreased the neurological changes arising from the exposure of the cerebral parenchyma. This work allowed us to validate the development of the experimental brain malaria framework in murine model and evaluate the neuroprotective effect of Acai (Euterpe oleracea) in the course of the disease.
Acesso aberto (Open Access)
Estudo da eficácia e tolerância do artesunato oral isolado e em associação com mefloquina, no tratamento da malária falciparum não complicada em área endêmica do Pará, Brasil
(1996-06) CARDOSO, Bernardo da Silva; DOURADO, Heitor Vieira; PINHEIRO, Maria da Conceição Nascimento; CRESCENTE, Jose Angelo Barletta; AMORAS, Walter Wanderley; BAENA, Jorge; SARATY, Sandra
With the objective to evaluate the efficacy and tolerance of artesunate in the treatment of non-complicatedfalciparum malaria in endemic area of the State of Pará, 153 patients were randomized and studied in three groups, distributed by therapeutical scheme (I received mefloquine lOOOmg, II used artesunate 600mg followed by mefloquine 500mg). Evaluation was made by daily clinical and parasithological examination, in the first 7 days, and weekly until the 35th day of the follow up. Biochemical and hematological analysis previously done and on the 7th day, targetting cure control and identification of possible effects related to drugs administration. As to sex, parasitemy and fever, studied groups were homogeneous. Time for parasitemy disappearence was shorter in the groups II and III respectively, whose therapeutical schemes had artesunate. Fever disappereance was quicker in the group treated with the combination of drugs. Clinical and biochemical alterations associated with drugs administration did not show significant differences among the studied groups. Early disappearence of fever and parasitemy, and absence of important side effects suggest that artesunate, isolated or administrated in combination with mefloquine, constitutes an able therapeutical procedure to contribute for disease control in that region.
Acesso aberto (Open Access)
Estudo de dose adequada da droga RO42-1611 (Arteflene) no tratamento da malária por Plasmodium falciparum
(Universidade Federal do Pará, 1997-12-04) SILVA, Rita do Socorro Uchôa; SOUZA, José Maria de; http://lattes.cnpq.br/6459204248879587
The increasing resistance of P. falciparum strains to the current antimalarial drugs makes the searching of new drugs an urgent task. The compound Ro 42-1611 is an antimalarial drug that arises from a chinese herb Artabotrys uncinatus. Since its synthesis, Ro 42-1611 was used in three different clinical trials to treat falciparum malaria in Africa, but how it works in the South America malaria patients is obscure. Althouh being an effective antimalarial, a proper therapeutic dose to achieve the supressive cure of falciparum malaria has not been established yet. The purpose of this study is to evaluate the tolerance, the toxicity and the efficacy of 3 different dose schedules of Ro 42-1611 in the treatment of falciparum malaria. It was an open, prospective and randomized trial carried out in Maraba/Para State in male patients with maximum 80 kg bodyweight. All patients had fever or another constitutional malaria symptom and had a positive thick blood smear to P. falciparum (≥ 200 and ≤ 50,000 parasites/mm³). In a hospital, they were assigned into 3 groups according to drug administration time: Group I - 1,500 mg twice a day for 24 hours; Group II - 1,500 mg twice a day for 48 hours and Group III - 1,500 mg twice a day for 72 hours. Before treatment, the following procedures were recorded from all patients: personal data, height and weight, malarial signs and symptoms, history of simultaneous drug intake, body temperature, vital functions (respiratory rate, blood pressure), parasite count, haematology and blood chemistry assesments and electrocardiogram. Ouring the treatment, all those parameters were followed, including adverse reactions to Ro 42-1611. Statistical analysis (Friedman variance test) were performed on laboratory tests results. Sixteen patients were enrolled in the study: 5 patients in Group I; 6 in Group II and 5 patients in Group III. Among patients, age ranged from 17 to 41 years old (mean 266). body weight from 44 to 72 kg (mean 54.9). The assexual parasite count ranged from 200 to 40,000 parasites/mm³ . Regarding those variables, there were homogeneity in 3 groups. According to the protocol, clinical and laboratory data were evaluated, with the following results: the minimum and the maximum fever clearence time was 9 to 48 hours respectively. The mean assexual parasite clearence was 53.6 hours, without any statistical significance among the groups (p=0.7264). There were statistical significative difference (p=0.0046) in the hematocrit values before treatment (00), and the third (02) and the eighth (07) day of the follow-up. It was observed an increase in the leukocyte count between 02 and 07, also of statistical significance (p=0.0171), as well in the platelets of 00 and 07/02 and 07 (p=0.0001). Between DO and 07, statistical significative reduction ocurred in the values of total bilirrubin (p=0.0024), alkaline phosphatase (p=0.0195) and urea (p=0.0168). There were no statistical significative difference nor in the evalution of electrocardiogram results neither in the blood pressure. Short adverse reactions were mild to moderate. In the end of the treatment, 87,5% of patients were completely free of parasites, but just 2 achieved a radical cure (12,5%), both included in Group III. Any of the schedule treatment showed efficacy. Perhaps such efficacy might be attained using Ro 42-1611 in a superior dose, for a longer period of time or in association with other antimalarial in further studies.
Acesso aberto (Open Access)
Estudo fitoquímico, avaliação da toxicidade oral aguda e da atividade antimalárica in vitro e in vivo das cascas de Parahancornia fasciculata (Poir.) Benoist (Apocynaceae)
(Universidade Federal do Pará, 2013) SILVA, Adreanne Oliveira da; OLIVEIRA, Alaíde Braga de; http://lattes.cnpq.br/3719659803766075; DOLABELA, Maria Fâni; http://lattes.cnpq.br/0458080121943649
Parahancornia fasciculata (Poir.) Benoist (Apocynaceae), also known as Parahancornia amapa (Hub.) Ducke is a species used in the treatment of malaria, uterus infections, gastritis, anemia, respiratory problems, among other ailments. The objectives of this study were to carry out the phytochemical study of the trunk bark from P. fasciculata, to evaluate the in vitro and in vivo antimalarial activity as well as the acute oral toxicity of extracts and fractions from this plant species. The powder bark of P. fasciculata was submitted to extractions by maceration/percolation with ethanol 96% and with dichloromethane after alkalinization of the bark powder affording the dry extracts EEPF and EDAPF, respectively. EEPF underwent two different re-extractions: 1) acid-base extractions affording the neutral (EEPFN) and alkaloidal fractions (EEPFA) and 2) heating under reflux with different solvents, leading to the fractions EEPF-DCM:HEX (1:1), EEPF-DCM: AcOEt (1:1) and EEPFinsoluble in AcOEt. Phytochemical screening of EEPF by TLC revealed the presence of triterpenes and steroids, flavonoid heterosides, saponins, polyphenols, tannins, anthracene heterosides and cardiotonic heterosides. EDAPF was submitted to chromatography through a silica gel column to give 30 fractions of which Fr1-3, Fr4, Fr5-7 and Fr11 represented most of the extract that was chromatographed. Fr5-7 led to the isolation of a mixture of esters of lupeol which are the major components of this extract. Saponification of this fraction afforded Fr5-7Hid that was analyzed by IV, 1H and 13CNMR and was identified as the triterpene lupeol. The insoluble AcOEt fraction derived from re-extraction of EEPF gave a positive test for proanthocyanidins which were quantitatively determined and the results were expressed in percentage for the content of these metabolites in an undiluted sample (10,46 ± 0,3419 %), a 1:10 diluted sample (9,94 ± 0,1598 %) and a 1:100 diluted sample (10,55 ± 0,9299%). The evaluation of the antiplasmodial activity in vitro was carried out against W2 strains of Plasmodium falciparum by the assay of the Histidine-Rich Protein II (HRPII) with EEPF, EEPFN, EEPFA, Fr1-3, Fr4, Fr5-7 (lupeol esters), Fr11 and Fr5-7Hid (lupeol). The best result was obtained for EEPF, EEPFA, EEPFN (CI50 = ~ 50 μg / mL) that can be considered as moderately active. The remaining samples showed CI50 > 50 μg / mL and were considered inactive. The in vivo antimalarial activity was performed in Swiss female mice infected with ANKA strains of Plasmodium berghei with EEPF and EEPF-DCM:HEX (1:1) at concentrations of 500, 250 and 125mg/kg body weight. EEPF was partially active only on the 8th day in all concentrations tested while EEPF-DCM:HEX (1:1) was partially active at a dosis of 500mg/kg and was inactive in the remaining doses. The acute oral toxicity test was determined for EEPF in Swiss female mice by the method of the fixed dose (5,000mg/kg) when no apparent signs of toxicity were observed what was confirmed by the absence of anatomic and histopathologic changes.
Acesso aberto (Open Access)
In vitro antimalarial activity of six Aspidosperma species from the state of Minas Gerais (Brazil)
(2012-12) DOLABELA, Maria Fâni; OLIVEIRA, Salma Gomes de; PERES, José M.; NASCIMENTO, José M. S.; PÓVOA, Marinete Marins; OLIVEIRA, Alaíde Braga de
Ethnomedicinal informations point to some Aspidosperma species (Apocynaceae) as antimalarial plants in Brazil and have motivated the evaluation of six species which were collected in the state of Minas Gerais: A. cylindrocarpon Müll. Arg., A. parvifolium A. DC., A. olivaceum Müll. Arg., A. ramiflorum Müll. Arg., A. spruceanum Benth. ex Müll. Arg. and A. tomentosum Mart.. A total of 23 extracts of different plant parts in different solvents were assayed in vitro against chloroquine-resistant (W2) and chloroquine-sensitive (3D7) strains of Plasmodium falciparum. All the extracts were shown to be active with IC50 values in the range of 5.0 ± 0 2.8 µg/mL to 65.0 ± 4.2 µg/mL. TLC profile of the extracts revealed the presence of alkaloids in the six species assayed. These results seem to confirm the popular use of Aspidosperma species to treat human malaria in Brazil and seem point to alkaloids as the putative active compounds of the assayed species.
Acesso aberto (Open Access)
Malária e migração no Amapá: projeção espacial num contexto de crescimento populacional
(Universidade Federal do Pará, 2005-04-29) ANDRADE, Rosemary Ferreira de; SIMONIAN, Ligia Terezinha Lopes; http://lattes.cnpq.br/6620574987436911
Malaria is still a serious public health problem, which continues to affect groups of the population living in the Amazon region. The main affected groups live in settlement areas and in artesanal gold mining camps (garimpos). This work aimed to analyze the relationship between the spread of the disease and the migratory process that leads people without any immunity against malaria to the areas of settlement and garimpos. This work also approached issues such as occupational activities, housing, and imported malaria cases from the international frontier with the Guyana. This study focused in the state of Amapa, specifically in the municiples of Ferreira Gomes, Porto Grande, Pedra Branca do Amapari, Serra do Navio, and Oiapoque where, from 1990 to 2003, the highest annual incidences of Plasmodium falciparum have been recorded for the urban sector, settlements, and garimpos. Both the exploratory/descriptive and ecological analysis systems were combined to describe the geographic areas. The data obtained by the Malaria Information System (SISMAL) and Epidemiological Watch System (SIVEP) supported the quantitative analysis and the qualitative approach of the malaria epidemics in the study area. Thematic maps were generated from geographic information system (GIS) data of the population under study and used the ArquiGiz system and the digital cartographic database of the Secretary for the Environment (SEMA). These maps allowed the spatial description, analysis, and discussion of the observed phenomena. The results lead to the conclusion that the occupational activity and housing have a direct relationship with the incidence of malaria. During the period under study, despite the policies used to control malaria, the studied areas remained as high-risk areas, and infection by P. falciparum increased, mainly in the geographic area of Oiapoque, an international frontier, where the imported cases presented the same tendency.
Acesso aberto (Open Access)
Malária em mulheres na idade reprodutiva: análise dos aspectos clínico-epidemiológicos na região de Itaituba, 2005 a 2007
(Universidade Federal do Pará, 2010) MELO, Wilson Franco de; PINHEIRO, Maria da Conceição Nascimento; http://lattes.cnpq.br/6353829454533268
A malária na gestação representa uma ameaça à vida da mãe e do concepto além de influenciar na evolução da gravidez. Visando esclarecer aspectos da malária que acomete gestantes de áreas hiperendêmicas na Amazônia, este estudo se propõe avaliar aspectos clínico-epidemiológicos da doença em mulheres na idade reprodutiva, com ênfase em gestantes internadas em hospital público de referencia para a região de Itaituba. O estudo foi conduzido no HMI de Itaituba no período de 2005 a 2007, através do levantamento de prontuários de mulheres hospitalizadas e com diagnóstico de malária confirmado pela gota espessa, e da análise documental baseada nos dados do SIVEP-Malária. Os resultados evidenciaram que no Pará, em 2007, mais de 51% dos casos notificados foram oriundos de apenas nove municípios, dois deles (Itaituba e Jacareacanga), pertencentes à microrregião de Itaituba, área onde foi registrada maior Incidência Parasitária Anual (IPA). Os dados dos prontuários de 30 pacientes (sete, gestantes) revelaram, em sua maioria, que eram procedentes da área rural do município de Itaituba e haviam sido infectadas por P. falciparum; que as gestantes eram as mais jovens (p<0,05); e que o tempo de internação foi similar entre gestantes e não-gestantes. As intercorrências sobre o curso gestacional foram um óbito fetal (malária por P. vivax, segundo trimestre) e um parto prematuro (malária por P. falciparum, terceiro trimestre). Concluiu-se, a partir dessas observações, que casos graves de malária podem ocorrer tanto associados à espécie vivax como falciparum fazendo-se necessário constante vigilância epidemiológica, especialmente no município de Itaituba, onde está concentrado o maior número de casos da doença. As medidas de vigilância epidemiológica a serem adotadas devem privilegiar o diagnóstico precoce e tratamento imediato das pacientes, sobretudo das gestantes, já que estão sujeitas a maior risco de complicações com sérias conseqüências para o concepto.
Acesso aberto (Open Access)
Validação de metodologia analítica para determinação de lumefantrina em plasma e sangue total adsorvido em papel de filtro por cromatografia líquida de alta eficiência (CLAE) em pacientes com malária por plasmodium falciparum
(Universidade Federal do Pará, 2010-10-07) PINHEIRO, Priscila de Nazaré Quaresma; VIEIRA, José Luiz Fernandes; http://lattes.cnpq.br/2739079559531098
Among the tools to achieve the optimal treatment for malaria, it highlights the concentration monitoring of antimalarials in biological fluids. Considering that Coartem ® is used in first-line therapy for treatment of falciparum malaria, it is appropriate that this study aims to validate an analytical methodology for determination of lumefantrine in whole blood samples, adsorbed on filter paper, and in plasma by high performance liquid chromatography (HPLC) in patients with falciparum malaria uncomplicated, using liquid-liquid extraction. Were carried out studies of selectivity, linearity, calibration curve, limits of detection and quantification, recovery, intra and inter assay precision, stability and robustness. The samples for study of applicability of the proposed method, were collected from patients with falciparum malaria using Coartem ® (artemether-20mg + lumefantrine-120mg) on D3. The optimized chromatographic conditions were: wavelength 335nm, flow 1.2 mL / min. and a mobile phase consisting of acetonitrile-water (60:40, v / v) pH = 3,5. The liquid-liquid extraction can be efficient, because the average recovery was 101.3% for plasma and 84.3% for whole blood. The method was selective and linear in the concentration range of 160 to 1760ng/mL. The limits of detection and quantitation was 32ng/mL and 160ng/mL. The average coefficient of variation intra assay, plasma and whole blood, respectively, were 10.88 and 8.38% and inter assay of 13.21 and 11.78%. The compound proved to be stable in whole blood absorbed onto filter paper for 70 days. Modification of pH, flow and mobile phase composition did not significantly alter the resolution of the analytes, suggesting an adequate strength. The method proved effective in quantifying lumefantrine in whole blood samples from patients with falciparum malaria and the validation parameters are consistent with the recommendations of regulatory agencies in Brazil.
Acesso aberto (Open Access)
Validação de metodologia analítica por cromatografia liquida de alta eficiencia (CLAE), para determinação de mefloquina e carboximefloquina em amostras de sangue total adsorvidas em papel de filtro, em pacientes com malária por Plasmodium falciparum
(Universidade Federal do Pará, 2010) ATAIDE, Patrícia Marques de; VIEIRA, José Luiz Fernandes; http://lattes.cnpq.br/2739079559531098
Among the main challenges for malaria control in Brazil and in the world, the advent of resistance to the Plasmodium, particularly Plasmodium falciparum, is presented as the most relevant. Mefloquine is a drug of first line for the treatment of falciparum malaria, and the availability of sensitive methods and low cost for monitoring of blood concentrations of the drug and carboxymefloquine assists in the optimization of drug regimens. In this sense, analytical methodology was validated in accordance with the parameters suggested by official regulatory agency for determination of mefloquine and its carboxylated derivative on the whole blood sample adsorbed on filter paper. The method was employed using High Performance Liquid Chromatography after liquid-liquid extraction of the analytes. The detection was performed at 222nm. No interference was observed in other antimalarials commonly used. The method was linear in concentration range from 0.25 to 2.5 μg/mL for mefloquine and its carboxylated derivative. The detection and quantification limits were 35 ng/mL and 70 ng/mL for mefloquine and carboxymefloquine, respectively. The average intra assay precision was 31±4% for mefloquine and 21±5% for carboxymefloquine. The average inter assay precision was 38±4% for mefloquine and 25±7% for carboxymefloquine. The average of recovery for concentrations of mefloquine ranging from 0.25 to 2.5μg/mL was 83±14% and carboxymefloquine varying from 0.375 to 3740 μg/mL was 88±11%. The drug was stable in samples adsorbed on filter paper for a period of a month. . The method showed to be robust for small changes on pH of the mobile phase. To evaluate the applicability of the method was performed determination of analytes in blood samples adsorbed on filter paper from patients with falciparum malaria. The average concentration of mefloquine was 0.861±0.723 μg/mL and carboxymefloquine 0.472±0.086 μg/mL. The validation parameters of the analytical methodology followed the recommendations proposed by the official agencies and the method showed to be appropriate for determination of mefloquine and carboxymefloquine in whole blood samples adsorbed on filter paper.