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1.
Int J Biol Macromol ; 165(Pt B): 1832-1841, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-33075341

RESUMO

Studies have shown that inhibition of Plasmodium falciparum Purine Nucleoside Phosphorylase (PfPNP) blocks the purine salvage pathway in vitro and in vivo. In this study, PfPNP was evaluated as a model in the search for new inhibitors using surface plasmon resonance (SPR). Its expression, purification, oligomeric state, kinetic constants, calorimetric parameters and kinetic mechanisms were obtained. PfPNP was immobilized on a CM5 sensor chip and sensorgrams were produced through binding the enzyme to the substrate MESG and interactions between molecules contained in 10 fractions of natural extracts. The oligomeric state showed that recombinant PfPNP is a hexamer. The true steady-state kinetic parameters for the substrate inosine were: KM 17 µM, kcat 1.2 s-1, VMax 2.2 U/mg and kcat/KM 7 × 10-4; for MESG they were: KM 131 µM, kcat 2.4 s-1, VMax 4.4 U/mg and kcat/KM 1.8 × 10-4. The thermodynamic parameters for the substrate Phosphate were: ΔG - 5.8 cal mol-1, ΔH - 6.5 cal mol-1 and ΔS - 2.25 cal mol-1/degree. The ITC results demonstrated that the binding of phosphate to free PfPNP led to a significant change in heat and association constants and thermodynamic parameters. A sequential ordered mechanism was proposed as the kinetic mechanism. Three plant extracts contained molecules capable of interacting with PfPNP, showing different levels of affinity. The identification of plant extract fractions containing molecules that interact with recombinant PfPNP using SRP validates this target as a model in the search for new inhibitors. In this study, we showed for the first time the true steady-state kinetic parameters for reactions catalyzed by PfPNP and a model using PfPNP as a target for High-throughput Screening for new inhibitors through SPR. This knowledge will allow for the development of more efficient research methods in the search for new drugs against malaria.


Assuntos
Inibidores Enzimáticos/análise , Inibidores Enzimáticos/farmacologia , Ensaios de Triagem em Larga Escala , Modelos Moleculares , Plasmodium falciparum/enzimologia , Purina-Núcleosídeo Fosforilase/antagonistas & inibidores , Bioensaio , Calorimetria , Guanosina/análogos & derivados , Guanosina/metabolismo , Hesperidina/química , Hesperidina/farmacologia , Cinética , Triterpenos Pentacíclicos/química , Triterpenos Pentacíclicos/farmacologia , Extratos Vegetais/química , Plasmodium falciparum/efeitos dos fármacos , Multimerização Proteica , Purina-Núcleosídeo Fosforilase/química , Quercetina/química , Quercetina/farmacologia , Proteínas Recombinantes/isolamento & purificação , Especificidade por Substrato , Ressonância de Plasmônio de Superfície , Termodinâmica , Tionucleosídeos/metabolismo
2.
BMC Complement Altern Med ; 15(1): 420, 2015 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-26608735

RESUMO

BACKGROUND: The Combretum leprosum Mart. plant, popularly known as mofumbo, is used in folk medicine for inflammation, pain and treatment of wounds. From this species, it is possible to isolate three triterpenes: (3ß, 6ß, 16ß-trihydroxylup-20(29)-ene) called lupane, arjunolic acid and molic acid. In this study, through preclinical tests, the effect of lupane was evaluated on the cytotoxicity and on the ability to activate cellular function by the production of TNF-α, an inflammatory cytokine, and IL-10, an immuno regulatory cytokine was assessed. The effect of lupane on the enzymes topoisomerase I and II was also evaluated. METHODS: For this reason, peripheral blood mononuclear cells (PBMCs) were obtained and cytotoxicity was assessed by the MTT method at three different times (1, 15 and 24 h), and different concentrations of lupane (0.3, 0.7, 1.5, 6, 3 and 12 µg/mL). The cell function was assessed by the production of TNF-α and IL-10 by PBMCs quantified by specific enzyme immunoassay (ELISA). The activity of topoisomerases was assayed by in vitro biological assays and in silico molecular docking. RESULTS: The results obtained showed that lupane at concentrations below 1.5 µg/mL was not toxic to the cells. Moreover, lupane was not able to activate cellular functions and did not alter the production of IL-10 and TNF-α. Furthermore, the data showed that lupane has neither interfered in the action of topoisomerase I nor in the action of topoisomerase II. CONCLUSION: Based on preclinical results obtained in this study, we highlight that the compound studied (lupane) has moderate cytotoxicity, does not induce the production of TNF-α and IL-10, and does not act on human topoisomerases. Based on the results of this study and taking into consideration the reports about the anti-inflammatory and leishmanicidal activity of 3ß, 6ß, 16ß-trihydroxylup-20(29)-ene, we suggest that this compound may serve as a biotechnological tool for the treatment of leishmaniasis in the future.


Assuntos
Anti-Inflamatórios/toxicidade , Combretum , Leucócitos Mononucleares/efeitos dos fármacos , Triterpenos/toxicidade , Anti-Inflamatórios/farmacologia , DNA Topoisomerases/metabolismo , Flores , Humanos , Interleucina-10/biossíntese , Extratos Vegetais/farmacologia , Extratos Vegetais/toxicidade , Triterpenos/farmacologia , Fator de Necrose Tumoral alfa/biossíntese
3.
Arq Gastroenterol ; 52(1): 18-21, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26017077

RESUMO

BACKGROUND: The Amazon is one of the regions who have the highest rates of infection by the hepatitis B virus in the world. Objectives This study aimed to evaluate the epidemiological data and spatial distribution of hepatitis B cases reported between 2002 and 2012 in the Brazilian State of Rondônia. METHODS: Social and clinical data of these individuals were studied through the Information System for Notifiable Diseases (SINAN), including the following variables: gender, age group, vaccination, contact with a known patient with HBV, exposure to risk factors, source of infection, and clinical status. RESULTS: There were 7,132 cases reported in Rondônia, with an average incidence rate of 42/100,000 inhabitants per year. The municipalities with the highest incidence rates were Monte Negro (187.6/100,000 inhabitants) and Ariquemes (157.2/100,000 inhabitants). The 20-39 year-old age group had the highest number of cases (n = 3,834), and 69.9% of patients were likely infected via sexual contact. Regarding the clinical disease status, most of the patients (80.7%) were in the chronic phase. CONCLUSIONS: There was a recent 402% increase in the diagnosis of hepatitis B, which is likely owing to the improvements in the public diagnostic system. This highlights the need for public policies to prevent and control the disease.


Assuntos
Hepatite B/epidemiologia , Adolescente , Adulto , Distribuição por Idade , Fatores Etários , Brasil/epidemiologia , Criança , Pré-Escolar , Métodos Epidemiológicos , Feminino , Sistemas de Informação em Saúde , Hepatite B/transmissão , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Adulto Jovem
4.
Toxicon ; 99: 16-22, 2015 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-25772860

RESUMO

The multidrug-resistant bacteria have become a serious problem to public health. In this scenery the antimicrobial peptides (AMPs) derived from animals and plants emerge as a novel therapeutic modality, substituting or in addition to the conventional antimicrobial. The anurans are one of the richest natural sources of AMPs. In this work several cycles of cDNA cloning of the skin of the Brazilian treefrog Hypsiboas semilineatus led to isolation of a precursor sequence that encodes a new AMP. The sequence comprises a 27 residue signal peptide, followed by an acidic intervening sequence that ends in the mature peptide at the carboxy terminal. The AMP, named Hs-1, has 20 amino acids residues, mostly arranged in an alpha helix and with a molecular weight of 2144.6 Da. The chemically synthesized Hs-1 showed an antimicrobial activity against all Gram-positive bacteria tested, with a range of 11-46 µM, but it did not show any effect against Gram-negative bacteria, which suggest that Hs-1 may have a selective action for Gram-positive bacteria. The effects of Hs-1 on bacterial cells were also demonstrated by transmission electron microscopy. Hs-1 is the first AMP to be described from H. semilineatus.


Assuntos
Proteínas de Anfíbios/farmacologia , Anti-Infecciosos/farmacologia , Peptídeos Catiônicos Antimicrobianos/farmacologia , Anuros/metabolismo , Descoberta de Drogas , Bactérias Gram-Positivas/efeitos dos fármacos , Pele/química , Sequência de Aminoácidos , Proteínas de Anfíbios/efeitos adversos , Proteínas de Anfíbios/química , Proteínas de Anfíbios/genética , Animais , Anti-Infecciosos/efeitos adversos , Anti-Infecciosos/química , Anti-Infecciosos/isolamento & purificação , Peptídeos Catiônicos Antimicrobianos/efeitos adversos , Peptídeos Catiônicos Antimicrobianos/química , Peptídeos Catiônicos Antimicrobianos/genética , Sequência de Bases , Células Sanguíneas/efeitos dos fármacos , Brasil , DNA Complementar/química , Florestas , Bactérias Gram-Positivas/crescimento & desenvolvimento , Bactérias Gram-Positivas/ultraestrutura , Humanos , Testes de Sensibilidade Microbiana , Microscopia Eletrônica de Transmissão , Dados de Sequência Molecular , Peso Molecular , Estabilidade Proteica , Estrutura Secundária de Proteína , Proteínas Recombinantes/efeitos adversos , Proteínas Recombinantes/química , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/farmacologia
5.
Arq. gastroenterol ; 52(1): 18-21, Jan-Mar/2015. tab, graf
Artigo em Inglês | LILACS | ID: lil-746480

RESUMO

Background The Amazon is one of the regions who have the highest rates of infection by the hepatitis B virus in the world. Objectives This study aimed to evaluate the epidemiological data and spatial distribution of hepatitis B cases reported between 2002 and 2012 in the Brazilian State of Rondônia. Methods Social and clinical data of these individuals were studied through the Information System for Notifiable Diseases (SINAN), including the following variables: gender, age group, vaccination, contact with a known patient with HBV, exposure to risk factors, source of infection, and clinical status. Results There were 7,132 cases reported in Rondônia, with an average incidence rate of 42/100,000 inhabitants per year. The municipalities with the highest incidence rates were Monte Negro (187.6/100,000 inhabitants) and Ariquemes (157.2/100,000 inhabitants). The 20-39 year-old age group had the highest number of cases (n = 3,834), and 69.9% of patients were likely infected via sexual contact. Regarding the clinical disease status, most of the patients (80.7%) were in the chronic phase. Conclusions There was a recent 402% increase in the diagnosis of hepatitis B, which is likely owing to the improvements in the public diagnostic system. This highlights the need for public policies to prevent and control the disease. .


Contexto A Amazônia é uma das regiões que possui as maiores taxas de infecção pelo vírus da hepatite B do mundo. Objetivos Esse estudo teve como objetivo avaliar dados epidemiológicos e a distribuição espacial dos casos de hepatite B notificados no Estado de Rondônia no período de 2002 a 2012. Métodos Foram estudados dados clínicos e sociais desses indivíduos através do Sistema de Informação de Agravos de Notificação (SINAN). Foram analisadas as seguintes variáveis: gênero, faixa etária, vacinação, contato com paciente sabidamente portador do vírus hepatite B, exposição do paciente aos fatores de risco, fonte de infecção e forma clínica. Resultados Foram notificados 7.132 casos, tendo uma incidência de 42/100.000 habitantes por ano. Os municípios que apresentaram as maiores taxas de incidência foram Monte Negro, 187,6/100.000 habitantes e Ariquemes, 157,2/100.000 habitantes. A faixa etária com maior número de casos foi de 20-39 anos (n=3.834), sendo que 69,9% dos pacientes se infectaram provavelmente por via sexual. Em relação à forma clínica da doença, a maioria dos pacientes (80,7%) se encontra na fase crônica. Conclusão Houve um aumento do diagnóstico do vírus da hepatite B da ordem de 402% nos últimos anos, seguramente pela melhora no sistema de diagnóstico da doença, sendo necessário uma maior atenção das políticas públicas de prevenção e controle da doença em função de sua elevada prevalência. .


Assuntos
Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Hepatite B/epidemiologia , Distribuição por Idade , Fatores Etários , Brasil/epidemiologia , Métodos Epidemiológicos , Sistemas de Informação em Saúde , Hepatite B/transmissão
6.
Rev Inst Med Trop Sao Paulo ; 57(1): 39-46, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25651325

RESUMO

INTRODUCTION: Hepatic capillariosis, caused by Capillaria hepatica (Calodium hepaticum) (Bancroft, 1893), Travassos, 1915 (Nematoda, Trichinelloidea, Capillariidae), is a common zoonosis in rodents but is rare in humans. Seventy-two cases in humans have been reported worldwide since the first case was described by MACARTHUR in 192417,27. This study aimed to determine the prevalence of Capillaria hepatica in humans and rodents in an urban area of Porto Velho, the capital of Rondônia, in Brazil. METHODS: After conducting a census of the area, 490 residents were randomly selected, and, after signing a term of consent, provided blood samples that were screened for anti-Capillaria hepatica antibodies. Simultaneously, rats were captured to assess the prevalence of this parasite in rodents by histopathological examination in liver sections. RESULTS: A prevalence of 1.8% was found among residents who had specific antibodies at a dilution of 1:150, indicating exposure to parasite eggs; 0.8% of the subjects also had positive titers at a dilution of 1:400, indicating true infection. The prevalence in rats was 2%. CONCLUSIONS: The prevalence of infection with this parasite among humans and rats was low. While the prevalence encountered among humans was within the limits reported in the literature, the prevalence among rodents was much lower.


Assuntos
Capillaria/imunologia , Reservatórios de Doenças , Infecções por Enoplida/epidemiologia , Hepatopatias Parasitárias/epidemiologia , Doenças dos Roedores/parasitologia , Animais , Brasil/epidemiologia , Infecções por Enoplida/diagnóstico , Humanos , Hepatopatias Parasitárias/diagnóstico , Hepatopatias Parasitárias/parasitologia , Prevalência , Ratos , Doenças dos Roedores/epidemiologia
7.
Rev. Inst. Med. Trop. Säo Paulo ; 57(1): 39-46, Jan-Feb/2015. tab
Artigo em Inglês | LILACS | ID: lil-736366

RESUMO

Introduction: Hepatic capillariosis, caused by Capillaria hepatica (Calodium hepaticum) (Bancroft, 1893), Travassos, 1915 (Nematoda, Trichinelloidea, Capillariidae), is a common zoonosis in rodents but is rare in humans. Seventy-two cases in humans have been reported worldwide since the first case was described by MACARTHUR in 192417,27. This study aimed to determine the prevalence of Capillaria hepatica in humans and rodents in an urban area of Porto Velho, the capital of Rondônia, in Brazil. Methods: After conducting a census of the area, 490 residents were randomly selected, and, after signing a term of consent, provided blood samples that were screened for anti-Capillaria hepatica antibodies. Simultaneously, rats were captured to assess the prevalence of this parasite in rodents by histopathological examination in liver sections. Results: A prevalence of 1.8% was found among residents who had specific antibodies at a dilution of 1:150, indicating exposure to parasite eggs; 0.8% of the subjects also had positive titers at a dilution of 1:400, indicating true infection. The prevalence in rats was 2%. Conclusions: The prevalence of infection with this parasite among humans and rats was low. While the prevalence encountered among humans was within the limits reported in the literature, the prevalence among rodents was much lower.


Introdução: Capilaríase hepática é causada pela Capillaria hepatica (syn. Calodium hepaticum) (Bancroft, 1893), Travassos, 1915 (Nematoda, Trichinelloidea, Capillariidae), sendo uma zoonose comum entre roedores, porém rara em humanos. Setenta e dois casos humanos foram relatados na literatura mundial desde o primeiro caso descrito por MACARTHUR em 192417,27. O objetivo desse estudo é determinar a prevalência da Capillaria hepatica em humanos e roedores de área urbana da cidade de Porto Velho, capital de Rondônia, Brasil. Método: Após realizar um censo da área, 490 moradores foram aleatoriamente selecionados e assinaram termo de consentimento, foram colhidas amostras de sangue para testar anticorpos anti-Capillaria hepatica. Simultaneamente, ratos foram capturados para determinação da prevalência deste parasita através do exame histopatológico em cortes de fígado. Resultados: Foi encontrada entre humanos prevalência de 1,8% de positividade para anticorpos específicos em diluição de 1:150, indicando exposição aos ovos do parasito; 0,8% desses também deram testes positivos quando seus soros sofreram diluição de 1:400, indicando infecção verdadeira. Nos ratos, a prevalência foi de 2%. Conclusão: A prevalência encontrada para o parasito entre homens e roedores foi baixa. Enquanto a prevalência encontrada entre humanos esteve dentro dos limites encontrados na literatura, a prevalência entre roedores foi bem menor.


Assuntos
Humanos , Animais , Ratos , Capillaria/imunologia , Reservatórios de Doenças , Infecções por Enoplida/epidemiologia , Hepatopatias Parasitárias/epidemiologia , Doenças dos Roedores/parasitologia , Brasil/epidemiologia , Infecções por Enoplida/diagnóstico , Hepatopatias Parasitárias/diagnóstico , Hepatopatias Parasitárias/parasitologia , Prevalência , Doenças dos Roedores/epidemiologia
8.
J Virol Methods ; 197: 19-24, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24316446

RESUMO

The hepatitis delta virus (HDV) is a pathogen that causes a severe and rapidly progressive disease of hepatocytes. The measurement of viral load in the peripheral blood of patients with HDV infections is important for diagnosis, treatment monitoring, and support for follow-up studies of viral replication during the course of the disease. This study reports the development of an assay capable of detecting and quantifying the abundance of HDV particles in serum samples, based on reverse-transcription quantitative PCR (RT-qPCR). Two standards for calibration were produced for determining the viral load of HDV: a cDNA cloned into a linear plasmid and a transcribed RNA. For validating this assay, 140 clinical samples of sera were used, comprising 100 samples from patients who tested positive for anti-HDV and hepatitis B virus surface antigen (HBsAg) by ELISA; 30 samples from blood donors; 5 samples monoinfected with hepatitis B virus (HBV); and 5 samples monoinfected with hepatitis C virus (HCV). The HDV RT-qPCR assay performed better when calibrated using the standard based on HDV cDNA cloned into a linear plasmid, yielding an efficiency of 99.8% and a specificity of 100% in the in vitro assays. This study represents the first HDV RT-qPCR assay developed with clinical samples from Brazil and offers great potential for new clinical efficacy studies of antiviral therapeutics for use in patients with hepatitis delta in the western Amazon region.


Assuntos
Hepatite D/diagnóstico , Vírus Delta da Hepatite/isolamento & purificação , Técnicas de Diagnóstico Molecular/métodos , Reação em Cadeia da Polimerase em Tempo Real/métodos , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Carga Viral/métodos , Brasil , Hepatite D/virologia , Vírus Delta da Hepatite/genética , Humanos
9.
Protein Expr Purif ; 92(1): 9-13, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23993978

RESUMO

Dengue is a major international public health concern. There is no drug to treat dengue virus infections and a vaccine is yet to be licensed. The laboratory diagnosis of dengue virus infection has been greatly improved during the last decade; therefore, the main limiting factor is the production of recombinant viral antigens on a large scale. Domain III of dengue virus envelope protein contains multiplex conformation-dependent neutralizing epitopes, making it an attractive diagnostic candidate. In this work, we have demonstrated the expression of dengue virus type 1 envelope domain III protein (EDIII-D1) in methylotrophic yeast, Pichia pastoris GS115. The recombinant secreted protein (sEDIII-D1) was purified by affinity chromatography and characterized by SDS-PAGE. Purified protein was recognized in immunoblot analysis and enzyme-linked immunosorbent assay (ELISA) with dengue-infected human serum samples. In conclusion, secreted expressions of domain III protein can be obtained in P. pastoris by methanol induction. This product has the potential to be used for the diagnosis of dengue infections.


Assuntos
Antígenos Virais/genética , Vírus da Dengue/genética , Dengue/diagnóstico , Dengue/virologia , Pichia/genética , Proteínas do Envelope Viral/genética , Sequência de Aminoácidos , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Antígenos Virais/química , Antígenos Virais/imunologia , Antígenos Virais/isolamento & purificação , Sequência de Bases , Clonagem Molecular/métodos , Dengue/sangue , Dengue/imunologia , Vírus da Dengue/química , Vírus da Dengue/imunologia , Vírus da Dengue/isolamento & purificação , Ensaio de Imunoadsorção Enzimática , Humanos , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Imunoglobulina M/sangue , Imunoglobulina M/imunologia , Dados de Sequência Molecular , Estrutura Terciária de Proteína , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/isolamento & purificação , Proteínas do Envelope Viral/química , Proteínas do Envelope Viral/imunologia , Proteínas do Envelope Viral/isolamento & purificação
10.
Mem Inst Oswaldo Cruz ; 108(1): 98-105, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23440122

RESUMO

The PfCLAG9 has been extensively studied because their immunogenicity. Thereby, the gene product is important for therapeutics interventions and a potential vaccine candidate. Antibodies against synthetic peptides corresponding to selected sequences of the Plasmodium falciparum antigen PfCLAG9 were found in sera of falciparum malaria patients from Rondônia, in the Brazilian Amazon. Much higher antibody titres were found in semi-immune and immune asymptomatic parasite carriers than in subjects suffering clinical infections, corroborating original findings in Papua Guinea. However, sera of Plasmodium vivax patients from the same Amazon area, in particular from asymptomatic vivax parasite carriers, reacted strongly with the same peptides. Bioinformatic analyses revealed regions of similarity between P. falciparum Pfclag9 and the P. vivax ortholog Pvclag7. Indirect fluorescent microscopy analysis showed that antibodies against PfCLAG9 peptides elicited in BALB/c mice react with human red blood cells (RBCs) infected with both P. falciparum and P. vivax parasites. The patterns of reactivity on the surface of the parasitised RBCs are very similar. The present observations support previous findings that PfCLAG9 may be a target of protective immune responses and raises the possibility that the cross reactive antibodies to PvCLAG7 in mixed infections play a role in regulate the fate of Plasmodium mixed infections.


Assuntos
Anticorpos Antiprotozoários/sangue , Anticorpos Antiprotozoários/imunologia , Antígenos de Protozoários/imunologia , Moléculas de Adesão Celular/imunologia , Malária Falciparum/imunologia , Malária Vivax/imunologia , Plasmodium falciparum/imunologia , Plasmodium vivax/imunologia , Proteínas de Protozoários/imunologia , Animais , Brasil , Portador Sadio , Reações Cruzadas , Ensaio de Imunoadsorção Enzimática , Eritrócitos/parasitologia , Feminino , Humanos , Malária Falciparum/parasitologia , Malária Vivax/parasitologia , Camundongos , Camundongos Endogâmicos BALB C
11.
Mem. Inst. Oswaldo Cruz ; 108(1): 98-105, Feb. 2013. ilus, graf, tab
Artigo em Inglês | LILACS | ID: lil-666051

RESUMO

The PfCLAG9 has been extensively studied because their immunogenicity. Thereby, the gene product is important for therapeutics interventions and a potential vaccine candidate. Antibodies against synthetic peptides corresponding to selected sequences of the Plasmodium falciparum antigen PfCLAG9 were found in sera of falciparum malaria patients from Rondônia, in the Brazilian Amazon. Much higher antibody titres were found in semi-immune and immune asymptomatic parasite carriers than in subjects suffering clinical infections, corroborating original findings in Papua Guinea. However, sera of Plasmodium vivax patients from the same Amazon area, in particular from asymptomatic vivax parasite carriers, reacted strongly with the same peptides. Bioinformatic analyses revealed regions of similarity between P. falciparum Pfclag9 and the P. vivax ortholog Pvclag7. Indirect fluorescent microscopy analysis showed that antibodies against PfCLAG9 peptides elicited in BALB/c mice react with human red blood cells (RBCs) infected with both P. falciparum and P. vivax parasites. The patterns of reactivity on the surface of the parasitised RBCs are very similar. The present observations support previous findings that PfCLAG9 may be a target of protective immune responses and raises the possibility that the cross reactive antibodies to PvCLAG7 in mixed infections play a role in regulate the fate of Plasmodium mixed infections.


Assuntos
Animais , Feminino , Humanos , Camundongos , Anticorpos Antiprotozoários/sangue , Anticorpos Antiprotozoários/imunologia , Antígenos de Protozoários/imunologia , Moléculas de Adesão Celular/imunologia , Malária Falciparum/imunologia , Malária Vivax/imunologia , Plasmodium falciparum/imunologia , Plasmodium vivax/imunologia , Proteínas de Protozoários/imunologia , Brasil , Portador Sadio , Reações Cruzadas , Ensaio de Imunoadsorção Enzimática , Eritrócitos/parasitologia , Camundongos Endogâmicos BALB C , Malária Falciparum/parasitologia , Malária Vivax/parasitologia
12.
J Virol Methods ; 186(1-2): 55-61, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22981980

RESUMO

Viruses belonging to the Flaviviridae family are found and distributed in most of the tropical and sub-tropical regions of the world. The genus has more than 56 members, most of which cause clinical symptoms in humans. The clinical diagnosis of dengue requires laboratory confirmation because of the similarity of symptoms with a series of other acute fevers and the primary use antibodies or antigens for detection. In this work, peptides E(1) and E(2) of the envelope protein (E) of the dengue virus were mapped using bioinformatics methods. These peptides were then expressed in a prokaryotic system and purified. An indirect ELISA for antibodies IgG and IgM from laboratory samples previously characterised was then used with the peptides to detect anti-dengue antibodies. For IgG using the peptide E(1), the sensitivity of the indirect ELISA was 88.3% and the specificity was 56%; using the peptide E(2), the sensitivity was 90% and the specificity was 59%; and using a combination of both peptides, the sensitivity was 93.3% and the specificity was 78%. For IgM using the peptide E(1), the sensitivity was 88% and the specificity was 66%; using the peptide E(2), the sensitivity was 88% and the specificity was 69%; and when used in combination, the peptides E(1)/E(2) demonstrated a sensitivity of 90% and a specificity of 86%. These results indicate that the use of the E(1) and E(2) peptides of the E protein are an alternative for serological diagnosis of dengue fever.


Assuntos
Anticorpos Antivirais/sangue , Vírus da Dengue/imunologia , Dengue/diagnóstico , Peptídeos , Proteínas do Envelope Viral , Vírus da Dengue/genética , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Peptídeos/genética , Peptídeos/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo , Sensibilidade e Especificidade , Testes Sorológicos/métodos , Proteínas do Envelope Viral/genética , Proteínas do Envelope Viral/metabolismo
13.
Epidemiol. serv. saúde ; 21(4): 627-634, 2012. graf
Artigo em Português | LILACS | ID: lil-661790

RESUMO

OBJETIVO: descrever a investigação de um surto de hepatite A no município de Ibiracatu, estado de Minas Gerais, Brasil, e relatar as medidas de controle adotadas. MÉTODOS: estudo descritivo do tipo série de casos; a investigação seguiu o roteiro de investigação de epidemia/surto do Ministério da Saúde. RESULTADOS: foram contabilizados 16 casos, sendo três confirmados por vínculo clínico-epidemiológico e 13 por pesquisa de anticorpo anti-VHAIgM; a maior incidência da doença foi em infantes de até dez anos de idade, dos quais a metade era de estudantes de uma escola pública local. CONCLUSÃO: as condições oferecidas pela escola favoreceram a disseminação da doença e as medidas realizadas para conter a veiculação viral foram adequadas e promoveram queda considerável na incidência da doença; o monitoramento epidemiológico e as medidas de intervenção colaboraram efetivamente para o rápido controle do surto.


OBJECTIVE: to describe the investigation of a hepatitis A outbreak in the municipality of Ibiracatu, state of Minas Gerais, Brazil, and to report the control measures taken. METHODS: descriptive study of case series type; the investigation followed the guideline for outbreak investigation of the Brazilian Ministry of Health. RESULTS: 16 cases were accounted, from which three were confirmedby clinical-epidemiological criteria and 13 by seropositiveness for anti-HAV Ig Mantibody; the highest prevalence was observed in children aged up to ten years old, from which 50 per cent were students of a local public school. CONCLUSION: the school conditions contributed to spreading the disease. The control measures taken to contain the viral transmission were appropriate and promoted a significant decrease in the disease incidence; the surveillance and control measures applied contributed to the quick control of the outbreak.


Assuntos
Masculino , Feminino , Prevenção de Doenças , Epidemiologia , Hepatite A
14.
Rev Soc Bras Med Trop ; 44(4): 528-30, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21860907

RESUMO

Flavivirus is a genus of arthropod-transmitted viruses of the family Flaviviridae, and in Brazil, up to eleven different Flavivirus have been isolated. We collected blood from farmers in the municipality of Theobroma, which is located 320km from the City of Porto Velho, the former capital of the Brazilian State of Rondônia. For viral isolation, we used newborn mouse brain, followed by RT-PCR with specific universal Flavivirus primers. We obtained fragments 958bp and 800bp in length. Based on BLAST, these sequences were 91% similar to a sequence of Cacipacore virus.


Assuntos
Infecções por Flavivirus/virologia , Flavivirus/genética , Animais , Brasil/epidemiologia , Flavivirus/classificação , Flavivirus/isolamento & purificação , Infecções por Flavivirus/epidemiologia , Humanos , Masculino , Camundongos , RNA Viral/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa
15.
Rev. Soc. Bras. Med. Trop ; 44(4): 528-530, July-Aug. 2011. ilus
Artigo em Inglês | LILACS | ID: lil-596610

RESUMO

Flavivirus is a genus of arthropod-transmitted viruses of the family Flaviviridae, and in Brazil, up to eleven different Flavivirus have been isolated. We collected blood from farmers in the municipality of Theobroma, which is located 320km from the City of Porto Velho, the former capital of the Brazilian State of Rondônia. For viral isolation, we used newborn mouse brain, followed by RT-PCR with specific universal Flavivirus primers. We obtained fragments 958bp and 800bp in length. Based on BLAST, these sequences were 91% similar to a sequence of Cacipacore virus.


Flavivirus é um gênero dos vírus transmitidos por artrópode da família Flaviviridae e, no Brasil, são isolados onze Flavivirus diferentes. Foi coletado o sangue de um agricultor, no município de Theobroma situado a 320km de distância da Cidade de Porto Velho, capital do Estado Brasileiro, Rondônia. Para isolamento viral, foi usado cérebro de camundongos recém-nascido, seguido por RT-PCR com primers universais específicos de Flavivirus. Nós obtivemos fragmentos com 958bp e 800bp de comprimento. Ao Blast das sequências obtivemos 91% de similaridade com uma sequência do vírus de Cacipacoré.


Assuntos
Animais , Humanos , Masculino , Camundongos , Infecções por Flavivirus/virologia , Flavivirus/genética , Brasil/epidemiologia , Infecções por Flavivirus/epidemiologia , Flavivirus/classificação , Flavivirus/isolamento & purificação , Reação em Cadeia da Polimerase Via Transcriptase Reversa , RNA Viral/genética
16.
Virol J ; 7: 315, 2010 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-21073730

RESUMO

BACKGROUND: Hepatitis B virus (HBV) can be classified into nine genotypes (A-I) defined by sequence divergence of more than 8% based on the complete genome. This study aims to identify the genotypic distribution of HBV in 40 HBsAg-positive patients from Rondônia, Brazil. A fragment of 1306 bp partially comprising surface and polymerase overlapping genes was amplified by PCR. Amplified DNA was purified and sequenced. Amplified DNA was purified and sequenced on an ABI PRISM® 377 Automatic Sequencer (Applied Biosystems, Foster City, CA, USA). The obtained sequences were aligned with reference sequences obtained from the GenBank using Clustal X software and then edited with Se-Al software. Phylogenetic analyses were conducted by the Markov Chain Monte Carlo (MCMC) approach using BEAST v.1.5.3. RESULTS: The subgenotypes distribution was A1 (37.1%), D3 (22.8%), F2a (20.0%), D4 (17.1%) and D2 (2.8%). CONCLUSIONS: These results for the first HBV genotypic characterization in Rondônia state are consistent with other studies in Brazil, showing the presence of several HBV genotypes that reflects the mixed origin of the population, involving descendants from Native Americans, Europeans, and Africans.


Assuntos
Vírus da Hepatite B/classificação , Vírus da Hepatite B/isolamento & purificação , Hepatite B/virologia , Adolescente , Adulto , Brasil , Análise por Conglomerados , Feminino , Genótipo , Vírus da Hepatite B/genética , Humanos , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Filogenia , Reação em Cadeia da Polimerase , Alinhamento de Sequência , Análise de Sequência de DNA , Proteínas Virais/genética , Adulto Jovem
17.
Plant Cell Rep ; 27(1): 117-24, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17917729

RESUMO

Guarana (Paullinia cupana var. sorbilis) is a plant native to the central Amazon basin. Roasted seed extracts have been used as medicinal beverages since pre-Colombian times, due to their reputation as stimulants, aphrodisiacs, tonics, as well as protectors of the gastrointestinal tract. Guarana plants are commercially cultivated exclusively in Brazil to supply the national carbonated soft-drink industry and natural product stores around the world. In this report, we describe and discuss the annotation of 15,387 ESTs from guarana seeded-fruits, highlighting sequences from the flavonoid and purine alkaloid pathways, and those related to biotic stress avoidance. This is the largest set of sequences registered for the Sapindaceae family.


Assuntos
Frutas/genética , Perfilação da Expressão Gênica/métodos , Paullinia/genética , Sementes/genética , Cafeína/metabolismo , Etiquetas de Sequências Expressas , Flavonoides/metabolismo , Frutas/metabolismo , Paullinia/metabolismo , Sementes/metabolismo , Clima Tropical
18.
Rev Soc Bras Med Trop ; 40(3): 268-71, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17653458

RESUMO

The first dengue fever epidemic in the State of Rondônia (western region of Brazil) was recorded in 1997, without laboratory confirmation. Following this, there was an epidemic in Manaus, in the neighboring State of Amazon, in 1998, in which DENV-1 and DENV-2 viruses were isolated from patients. In the present paper, the serotype characterization of the dengue virus isolated from patients with clinically suspected dengue in Porto Velho, Rondônia, between 2001 and 2003 is described. One hundred and fifty blood samples were collected between the first and fifth days of symptoms. Seventy samples of virus isolates were subjected to dengue identification by means of RT-PCR using universal primers for the NS1 gene of DENV, which amplifies a 419 bp fragment. The amplicons obtained were subjected to enzymatic digestion to characterize the viral serotypes. All the samples analyzed were DENV-1. A nucleotide sequence randomly selected from one amplicon, which was also DENV-1, presented 98% similarity to sequences from Southeast Asia that were obtained from GenBank.


Assuntos
Vírus da Dengue/genética , Dengue/virologia , RNA Viral/genética , Sequência de Bases , Brasil/epidemiologia , Primers do DNA/genética , Dengue/epidemiologia , Surtos de Doenças , Humanos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sorotipagem/métodos , Proteínas não Estruturais Virais/genética
19.
Rev. Soc. Bras. Med. Trop ; 40(3): 268-271, maio-jun. 2007. ilus
Artigo em Inglês | LILACS | ID: lil-456317

RESUMO

The first dengue fever epidemic in the State of Rondônia (western region of Brazil) was recorded in 1997, without laboratory confirmation. Following this, there was an epidemic in Manaus, in the neighboring State of Amazon, in 1998, in which DENV-1 and DENV-2 viruses were isolated from patients. In the present paper, the serotype characterization of the dengue virus isolated from patients with clinically suspected dengue in Porto Velho, Rondônia, between 2001 and 2003 is described. One hundred and fifty blood samples were collected between the first and fifth days of symptoms. Seventy samples of virus isolates were subjected to dengue identification by means of RT-PCR using universal primers for the NS1 gene of DENV, which amplifies a 419 bp fragment. The amplicons obtained were subjected to enzymatic digestion to characterize the viral serotypes. All the samples analyzed were DENV-1. A nucleotide sequence randomly selected from one amplicon, which was also DENV-1, presented 98 percent similarity to sequences from Southeast Asia that were obtained from GenBank.


A primeira epidemia de febre do dengue no Estado de Rondônia, Região Ocidental do Brasil foi registrado em 1997, sem confirmação laboratorial. Em seguida, houve uma epidemia descrita em 1998, em Manaus, no vizinho Estado do Amazonas, onde os vírus DENV-1 e DENV-2 foram isolados de pacientes. No presente artigo, foi descrito a caracterização do sorotipo do vírus dengue isolado de pacientes com suspeitas clinicas de dengue em Porto Velho, Rondônia, entre 2001 a 2003. Foram coletadas 150 amostras de sangue, entre primeiro e quinto dia de sintomas. Setenta amostras de vírus isolados foram submetidas a identificação do dengue pela RT-PCR usando primers universais para gene da NS1 do DENV que amplifica um fragmento de 419pb. O amplicon obtidos foram submetidos a digestão enzimática para caracterização do sorotipo viral. Todas as amostras analisadas foram DENV-1. A seqüência nucleotídica de um dos amplicons aleatoriamente selecionada também DENV-1 demonstrou 98 por cento similaridade com as seqüências do Sudeste Asiático obtidas no GenBank.


Assuntos
Humanos , Vírus da Dengue/genética , Dengue/virologia , RNA Viral/genética , Sequência de Bases , Brasil/epidemiologia , Surtos de Doenças , Primers do DNA/genética , Dengue/epidemiologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sorotipagem/métodos , Proteínas não Estruturais Virais/genética
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