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1.
Article in Chinese | WPRIM | ID: wpr-921789

ABSTRACT

Arthropod-borne diseases, such as malaria and dengue fever, have frequently beset five countries(Cambodia, Vietnam, Laos, Myanmar, and Thailand) in the tropical rainy Lancang-Mekong region, which pose a huge threat to social production and daily life. As a resort to such diseases, chemical drugs risk the resistance in plasmodium, non-availability for dengue virus, and pollution to the environment. Traditional medicinal plants have the multi-component, multi-target, and multi-pathway characteristics, which are of great potential in drug development. Exploring potential medicinals for arthropod-borne diseases from traditional medicinal plants has become a hot spot. This study summarized the epidemiological background of arthropod-borne diseases in the Lancang-Mekong region and screened effective herbs from the 350 medicinal plants recorded in CHINA-ASEAN Traditional Medicine. Based on CNKI, VIP, and PubMed, the plants for malaria and dengue fever and those for killing and repelling mosquitoes were respectively sorted out. Their pharmacological effects and mechanisms were reviewed and the material basis was analyzed. The result is expected to serve as a reference for efficient utilization of medicinal resources, development of effective and safe drugs for malaria and dengue fever, and the further cooperation between China and the other five countries in the Lancang-Mekong region.


Subject(s)
Animals , Culicidae , Malaria , Plants, Medicinal , Plasmodium , Thailand
2.
Article in Chinese | WPRIM | ID: wpr-888193

ABSTRACT

As a unicellular organism, Plasmodium displays a panoply of lipid metabolism pathways that are seldom found together in a unicellular organism. These pathways mostly involve the Plasmodium-encoded enzymatic machinery and meet the requirements of membrane synthesis during the rapid cell growth and division throughout the life cycle. Different lipids have varied synthesis and meta-bolism pathways. For example, the major phospholipids are synthesized via CDP-diacylglycerol-dependent pathway in prokaryotes and de novo pathway in eukaryotes, and fatty acids are synthesized mainly via type Ⅱ fatty acid synthesis pathway. The available studies have demonstrated the impacts of artemisinin and its derivatives, the front-line compounds against malaria, on the lipid metabolism of Plasmodium. Therefore, this article reviewed the known lipid metabolism pathways and the effects of artemisinin and its derivatives on these pathways, aiming to deepen the understanding of lipid synthesis and metabolism in Plasmodium and provide a theoretical basis for the research on the mechanisms and drug resistance of artemisinin and other anti-malarial drugs.


Subject(s)
Antimalarials/pharmacology , Artemisinins/therapeutic use , Humans , Lipid Metabolism , Malaria/drug therapy , Plasmodium
3.
São Paulo; SES/SP; 2021. 41 p. graf.
Monography in Portuguese | LILACS, ColecionaSUS, SES-SP, SESSP-SUCENPROD, SES-SP | ID: biblio-1151866

ABSTRACT

Introdução. A malária é uma doença infecciosa vetorial sendo atualmente considerada uma das maiores protozooses do mundo, mantendo-se endêmica principalmente na África, na região Amazônica da América do Sul e no Sudeste Asiático. Essa doença é causada por protozoários do gênero Plasmodium, sendo que cinco espécies são capazes de infectar humanos: P. vivax, P. falciparum, P. malariae, P. ovale e o mais recente, P. knowlesi, que é considerado como um parasito zoonótico. Há fatos que demonstram que esses parasitas que hoje infectam humanos, descendem de Plasmodium símios, e as infecções de símios continuam ocorrendo até os dias atuais. No Brasil os principais agentes de malária símia são Plasmodium brasilianum e Plasmodium simium (similar com P. malariae e P. vivax, respectivamente), sendo que esses dois parasitos estão envolvidos em situações zoonóticas no bioma Mata Atlântica, sendo o seu vetor o Anopheles cruzii. Tendo em vista esse cenário epidemiológico da malária residual, foi verificada a importância de realizar uma revisão sobre os principais estudos baseados e detecção de Plasmodium em fezes de primatas não humanos. Objetivo. Realizar uma revisão bibliográfica e atualização das principais técnicas existentes de detecção de Plasmodium em fezes de primatas não humanos descritas na literatura; bem como conhecer e realizar as técnicas de extração de DNA de fezes de primatas não humanos e técnicas de PCR em tempo real e PCR convencional para rastreamento de DNA de primatas não humanos e de plasmódios. Materiais e Métodos. Foi realizado levantamento bibliográfico nas bases de dados da SciELO, Lilacs, PubMed, MedLine e na Biblioteca Virtual em Saúde (BVS), de artigos e livros que descrevam a utilização de técnicas de detecção de Plasmodium em fezes de primatas não humanos, utilizando um total de 46 artigos publicados entre os anos de 1951 a 2021. Resultados. No delineamento da revisão foram selecionados 46 artigos que apresentassem menção explicita sobre as técnicas de detecção de Plasmodium, fezes e/ou menção explicita sobre malária e/ou malária símia. Na prática laboratorial, foram realizadas extrações de DNA e realizadas reações de PCR em Tempo real (TaqMan 18S rRNA) e PCR para amplificação de fragmento de cyt b de gênero Plasmodium em trinta e cinco amostras fecais de Alouatta guariba clamitans do Parque Estadual da Cantareira, município de São Paulo (Projeto FAPESP 2014/10.919-4, coordenado pela Dra. Ana Maria R. de C. Duarte). Discussão/Conclusão. Após a realização da revisão e das práticas laboratoriais, foi possível conhecer a abrangência do uso da técnica não invasiva e diagnostico de plasmódios em fezes de primatas não humanos no mundo, em especial na África e Sudeste Asiático, e também levantar as principais vantagens e desvantagens da utilização de fezes para detecção de Plasmodium. Diante disso, conclui-se que a utilização das técnicas PCR utilizando DNA oriundo das fezes podem trazer relevantes benefícios nos estudos de malária símia e humana em situações zoonóticas, bem como auxiliar nas atividades de Vigilância e Controle.


Subject(s)
Plasmodium , Feces , Malaria
4.
Rio de Janeiro; s.n; 2020. xv, 81 p. ilus.
Thesis in Portuguese | LILACS | ID: biblio-1128701

ABSTRACT

A malária cerebral (MC) é responsável por muitas mortes ocasionadas pela infecção por Plasmodium falciparum. Devido à dificuldade em estudar os mecanismos imunes envolvidos no desenvolvimento de MC em humanos, o uso de modelos murinos de malária cerebral experimental (MCE) tem sido amplamente empregado. Este estudo tem como objetivo investigar o papel das células imunes inatas no desenvolvimento ou não de MCE utilizando os modelos experimentais de camundongos C57BL/6 e BALB/c infectados com Plasmodium berghei ANKA. A sobrevida, parasitemia, peso, temperatura corporal e a quebra da barreira hematoencefálica confirmaram a resistência e suscetibilidade dos camundongos BALB/c e C57BL/6 parasitados ao desenvolvimento de MCE, respectivamente. Embora os camundongos BALB/c e C57BL/6 infectados tenham apresentado diferentes cursos clínicos da doença, eles exibiram a mesma parasitemia. A esplenomegalia foi observada em ambas as linhagens de camundongos durante a infecção. Entre as subpopulações mieloides investigadas, encontramos o influxo de neutrófilos e monócitos inflamatórios em cinética e proporções diferentes entre as linhagens. Já os macrófagos da polpa vermelha (MPV) dos camundongos BALB/c mantiveram seus valores constante ao longo da infecção, entretanto, responderam ao processo infeccioso ampliando a expressão do receptor de manose CD206. Interessantemente, os animais C57BL/6 apresentaram redução no número total dos MPV e MPV CD206+ após a infecção.


A redução nos valores de MPV CD206+ foi acompanhada pelo aumento no número e percentual de MPV iNOS+. Curiosamente, o número total de macrófagos da polpa branca (MPB) e MPB iNOS+ aumentou nos animais BALB/c e se manteve constante nos animais C57BL/6 infectados. Ao avaliarmos a expressão de CD206 nos MPB, observamos diminuição no percentual e número total dessas células em ambos os animais após infecção. Também realizamos a análise da expressão de CD206 e iNOS em microglias, macrófagos residentes do sistema nervoso central. Estas células, em ambas as linhagens, apresentaram a mesma cinética de aumento na expressão do receptor de manose CD206, e redução diferenciada na expressão de iNOS ao longo da infecção. Toda essa regulação dos marcadores fenotípicos nos macrófagos esplênicos de camundongos BALB/c ocorreu na presença de níveis séricos elevados de INF-γ e da citocina regulatória IL-10, no 4º dia após infecção, quando comparados aos camundongos C57BL/6. Nossos dados sugerem que, apesar de camundongos resistentes à MCE desenvolverem uma forte resposta imune ao parasito, o animal é favorecido pelo desencadeamento de um perfil antiinflamatório de resposta, como a ativação de macrófagos do tipo M2 e produção de citocinas regulatórias. Enquanto que os animais suscetíveis ao desenvolvimento de MCE respondem a infecção montando uma resposta com perfil pró-inflamatório nos momentos inicias da resposta imune, através do aumento no número de macrófagos com perfil M1 e pela produção de TNF e IL-6. (AU)


Subject(s)
Humans , Mice , Plasmodium , Malaria, Cerebral , Immunity, Innate , Macrophages
5.
Mem. Inst. Oswaldo Cruz ; 115: e200043, 2020. tab, graf
Article in English | LILACS, SES-SP | ID: biblio-1135250

ABSTRACT

BACKGROUND The number of malaria cases in Roraima nearly tripled from 2016 to 2018. The capital, Boa Vista, considered a low-risk area for malaria transmission, reported an increasing number of autochthonous and imported cases. OBJECTIVES This study describes a spatial analysis on malaria cases in an urban region of Boa Vista, which sought to identify the autochthonous and imported cases and associated them with Anopheles habitats and the potential risk of local transmission. METHODS In a cross-sectional study at the Polyclinic Cosme e Silva, 520 individuals were interviewed and diagnosed with malaria by microscopic examination. Using a global positional system, the locations of malaria cases by type and origin and the breeding sites of anopheline vectors were mapped and the risk of malaria transmission was evaluated by spatial point pattern analysis. FINDINGS Malaria was detected in 57.5% of the individuals and there was a disproportionate number of imported cases (90.6%) linked to Brazilian coming from gold mining sites in Venezuela and Guyana. MAIN CONCLUSIONS The increase in imported malaria cases circulating in the west region of Boa Vista, where there are positive breeding sites for the main vectors, may represent a potential condition for increased autochthonous malaria transmission in this space.


Subject(s)
Humans , Animals , Male , Female , Adult , Plasmodium/isolation & purification , Travel , Miners/statistics & numerical data , Mosquito Vectors/parasitology , Malaria/diagnosis , Malaria/transmission , Anopheles/parasitology , Plasmodium/classification , Urban Population , Venezuela , Brazil/epidemiology , Cross-Sectional Studies , Geographic Information Systems , Spatial Analysis , Gold , Guyana , Malaria/parasitology , Malaria/epidemiology , Anopheles/classification , Middle Aged
6.
Rev. bras. parasitol. vet ; 29(3): e000920, 2020. tab, graf
Article in English | LILACS | ID: biblio-1138103

ABSTRACT

Abstract The aim of this study was to verify the presence and identify the species of haemosporidian parasites in eared doves (Zenaida auriculata) in Brazil. Two hundred and eleven male and female eared doves were trap-captured in four different regions of Londrina city, in southern Brazil. Whole blood was collected in EDTA tubes through heart puncture after euthanasia in a CO2 chamber. A nested PCR targeting the mitochondrial cytochrome b gene (cyt b) of Haemoproteus spp./Plasmodium spp. was performed, followed by an enzymatic digestion to identify the genus. Phylogenetic trees were constructed to determine the closely related species. Out of 211 eared doves, 209 (99.05%) were positive for Haemoproteus spp. and/or Plasmodium spp. RFLP analysis showed that 72.72% (152/209) of eared doves were positive only for Haemoproteus spp., 6.22% (13/209) were positive only for Plasmodium spp., and 21.05% (44/209) of eared doves had mixed infections. Genetic analysis found four samples that were homologous with Haemoproteus multipigmentatus and one that was homologous with Plasmodium sp. This is the first molecular study of hemoparasites from eared doves in Brazil, and it is also the first description of H. multipigmentatus and Plasmodium spp. infection in eared doves in Brazil.


Resumo O objetivo deste estudo foi verificar a presença e a identificação espécies de parasitas hemosporídeos em pombos (Zenaida auriculata) no Brasil. Duzentos e onze pombos machos e fêmeas foram capturados em quatro regiões diferentes de Londrina, sul do Brasil. Amostra de sangue foi coletada em tubos contendo EDTA por meio de punção cardíaca, após eutanásia em câmara de CO2. Uma nested PCR com alvo no gene mitocondrial citocromo b (cyt b) de Haemoproteus spp./Plasmodium spp. foi realizada, seguida de digestão enzimática para identificar o gênero. A árvore filogenética foi construída para determinar a relação com outras espécies. Das 211 pombas, 209 (99,05%) foram positivas para Haemoproteus spp./Plasmodium spp. A análise RFLP demonstrou que 72,72% (152/209) das pombas foram positivas somente para Haemoproteus spp.; 6,22% (13/209) foram positivas somente para Plasmodium e 21,05% (44/209) das pombas tiveram infecções mistas. A análise genética mostrou quatro amostras homólogas com H. multipigmentatus e uma com Plasmodium spp. Este é o primeiro estudo molecular de hemoparasitas em pombos no Brasil. E é também a primeira descrição da infecção por H. multipigmentatus e Plasmodium spp. em pombos Z. auriculata no Brasil.


Subject(s)
Humans , Animals , Male , Columbidae/parasitology , Plasmodium/classification , Protozoan Infections, Animal/diagnosis , Bird Diseases/diagnosis , Bird Diseases/parasitology , Apicomplexa/classification , Apicomplexa/genetics , Phylogeny , Plasmodium/genetics , Protozoan Infections, Animal/parasitology , Brazil , Polymerase Chain Reaction/veterinary
7.
Rev. chil. infectol ; 36(3): 341-352, jun. 2019. graf
Article in Spanish | LILACS | ID: biblio-1013792

ABSTRACT

Resumen La malaria asociada al embarazo es un evento poco estudiado en América Latina. Los abundantes trabajos sobre el problema en África llevan a pensar que esta infección genera una modulación de la respuesta inmune y alteraciones en el ambiente placentario, eventos cruciales para el adecuado desarrollo del feto y el neonato. La inmunidad contra Plasmodium spp es compleja porque involucra diversos factores que amplían las posibilidades de desenlaces, los que finalmente conducen a los diferentes fenotipos clínicos de la enfermedad. Uno de los desenlaces inmunológicos en infecciones por Plasmodium spp es la modulación de la respuesta inmune hacía un perfil regulador. Esta regulación inducida por la infección malárica resulta ventajosa para la persistencia del parásito en el hospedero, y adicionalmente, podría generar eventos adversos en la respuesta inmune general de los individuos infectados. El objetivo de esta revisión es abordar los mecanismos con los cuales Plasmodium spp modula la respuesta inmune del hospedero y exponer las consecuencias de las infecciones maláricas en el contexto madre-neonato.


Pregnancy-associated malaria is an understudied event in Latin America. Most works about malaria in pregnancy have been conducted in Africa. These studies indicate that the infection generates immune response modulation and alterations in the placental environment, key factors for the proper development of the fetus and neonate. Immunity against Plasmodium spp is complex since involves several factors that increase the possible infection outcomes. One of these immunological outcomes is the immune response modulation towards a regulatory profile, which is advantageous for the persistence of the parasite in the host; additionally, it could generate adverse events in the general immune response of infected individuals. The objective of this review is to address the Plasmodium spp mechanisms of modulation in the host immune response and expose the consequences of malarial infections in the mother-neonate context.


Subject(s)
Humans , Female , Pregnancy , Infant, Newborn , Plasmodium/immunology , Pregnancy Complications, Parasitic/immunology , Immunomodulation/physiology , Malaria/immunology , Placenta/immunology , Placenta/parasitology , Plasmodium/physiology , Host-Parasite Interactions/immunology , Immune System/immunology
8.
Rev. bras. parasitol. vet ; 28(1): 68-79, Jan.-Mar. 2019. tab, graf
Article in English | LILACS | ID: biblio-990803

ABSTRACT

Abstract Avian malaria is one of the most important diseases of captive penguins. We employed morphometric techniques to evaluate hepatic hemosiderosis in rehabilitating wild Magellanic penguins (Spheniscus magellanicus) that were negative (n = 9) or naturally infected by different subgenera of Plasmodium spp. (n = 24), according with: Plasmodium subgenera (Haemamoeba, Huffia, Other lineages, and Unidentified lineages), severity of Plasmodium histopathological lesions, and concurrent diseases, age class (juvenile or adult plumage), sex (male, female or not determined), body score (emaciated, thin, good, excellent, not available), molt, presence or absence of oil contamination upon admission, iron supplementation, and rehabilitation center. The percentage of the area occupied by hemosiderin was called 'Index of Hepatic Hemosiderosis (IHH)'. Plasmodium-positive females presented significantly higher IHH values (17.53 ± 12.95%) than males (7.20 ± 4.25%; p = 0.041). We observed higher levels of congestion (p = 0.0182) and pneumonia (p = 0.0250) severity between Unidentified lineages vs. Huffia. We believe that the hepatic hemosiderosis observed in this study was multifactorial, the result of pathological processes caused by malaria, molting, hemoglobin and myoglobin catabolism during migration, anemia, concomitant diseases, and iron supplementation, all possibly potentiated by decreased liver mass. Further studies are needed to clarify the mechanisms of these hypotheses.


Resumo Malária aviária é uma das mais relevantes doenças em pinguins cativos. Foram aplicadas técnicas morfométricas para avaliar a hemossiderose hepática em pinguins-de-Magalhães (Spheniscus magellanicus ) de vida livre em reabilitação negativos (n = 9) e naturalmente infectados por diferentes subgêneros de Plasmodium spp. (n = 24), quanto a: subgênero de Plasmodium (Haemamoeba , Huffia, Outras Linhagens, e Linhagens não identificadas), severidade das lesões histopatológicas causadas por Plasmodium e doenças concomitantes, faixa etária (plumagem juvenil ou adulta), sexo (macho, fêmea, indeterminado), condição corporal (emaciado, magro, bom, excelente, indisponível), muda, presença/ausência de óleo a admissão, suplementação de ferro, e centro de reabilitação. A porcentagem da área ocupada por hemossiderina foi denominada "Índice de Hemossiderose Hepática (IHH)". Fêmeas Plasmodium -positivas apresentaram IHH significativamente mais elevado que machos, respectivamente, 17,53 ± 12,95% e 7,20 ± 4,25% (p = 0,041). Níveis mais elevados de congestão (p = 0,0182) e pneumonia (p = 0,0250) foram observados entre Linhagens não identificadas vs. Huffia. Possivelmente, a hemossiderose hepática observada nesse estudo seja multifatorial, resultado de processos patológicos causados por malária, muda, catabolismo de hemoglobina e mioglobina durante a migração, anemia, doenças concomitantes e suplementação de ferro, potencialmente intensificados por massa hepática reduzida. Estudos complementares são necessários para esclarecer os mecanismos de tais hipóteses.


Subject(s)
Animals , Male , Female , Plasmodium/classification , Bird Diseases/parasitology , Spheniscidae/parasitology , Hemosiderosis/parasitology , Liver Diseases/parasitology , Malaria, Avian/parasitology , Bird Diseases/pathology , Severity of Illness Index , Hemosiderosis/pathology , Liver Diseases/pathology , Malaria, Avian/complications , Malaria, Avian/pathology , Animals, Wild
9.
São Paulo; s.n; 2019. 153 p.
Thesis in Portuguese | LILACS | ID: biblio-1026004

ABSTRACT

Introdução - Nyssorhynchus darlingi e outros mosquitos da subfamília Anophelinae atuam como vetores dos parasitos da malária humana. Alterações na paisagem podem alterar a distribuição, abundância e comportamento desses mosquitos. Bactérias presentes no intestino médio de vetores de Plasmodium são capazes de modular a infecção por Plasmodium spp. no mosquito. Objetivos - Ampliar o conhecimento sobre os mosquitos que atuam na dinâmica de transmissão da malária em áreas rurais e periurbanas da Amazônia brasileira e investigar a diversidade bacteriana associada ao abdômen de Ny. darlingi e Nyssorhynchus braziliensis. Métodos - Capturas de mosquitos foram realizadas em áreas rurais e periurbanas da Amazônia brasileira. Testes de detecção de Plasmodium spp. foram realizados nos mosquitos. Análises de correlação e de regressão foram realizadas entre métricas de paisagem e as variáveis: incidência acumulada de malária, número de Ny. darlingi, mosquitos infectados e taxa de picada humana. Sequenciamento da região V4 do gene 16S rRNA foi realizado para explorar a diversidade bacteriana associada ao abdômen de Ny. braziliensis e de Ny. darlingi naturalmente infectado e não infectado por Plasmodium spp. Resultados - Nyssorhynchus darlingi, Nyssorhynchus rangeli, Nyssorhynchus benarrochi B e Nyssorhynchus konderi B foram encontrados infectados com Plasmodium. Plasmodium vivax e Plasmodium falciparum foram as espécies do parasito encontradas nos vetores. Foram encontradas correlações positivas entre incidência acumulada de malária e as variáveis taxa de picada humana, densidade de borda e número de Ny. darlingi. Porcentagem de cobertura florestal e taxa de picada humana apresentaram correlação negativa. O período entre 0 h:00 e 3 h:00 foi o que apresentou maior número de mosquitos infectados. Não houve diferença estatística entre a diversidade bacteriana de Ny. darlingi infectado e não infectado. Asaia e Serratia estavam presentes em ambas as espécies de Nyssochynchus. Enterobacter foi encontrado apenas em abdômen de Ny. darlingi não infectado e Pseudomonas foi o gênero mais abundante. Conclusão - Este estudo reporta pela primeira vez a infecção natural por Plasmodium em Ny. konderi B e Ny. benarrochi B em regiões da Amazônia brasileira. Os resultados obtidos sugerem que mudanças na paisagem podem favorecer a ocorrência de novos vetores e consequentemente, aumentar o número de casos de malária em regiões endêmicas. O encontro de maior número de mosquitos infectados após a meia-noite contribui para as medidas de controle do vetor e confirma a importância do uso de mosquiteiros impregnados com inseticida. A presença de Asaia e Serratia em ambas as espécies de Nyssorhynchus e a alta prevalência de Pseudomonas em Ny. darlingi indicam a necessidade de outros estudos sobre a possível utilização destas bactérias no controle da malária através da paratransgênese. A presença do gênero Enterobacter apenas em abdômen de Ny. darlingi não infectado sugere que bactérias deste gênero possam oferecer proteção a infecção por Plasmodium e outros estudos devem ser realizados para verificar essa hipótese.


Introduction - Nyssorhynchus darlingi and other mosquitoes of the subfamily Anophelinae act as vectors of human malaria parasites. Landscape changes can alter the distribution, abundance and behavior of these mosquitoes. Bacteria present in the midgut of Plasmodium vectors are able to modulate infection by Plasmodium spp. in the mosquito. Objectives - To broaden the knowledge about mosquitoes that act on the dynamics of malaria transmission in rural and peri-urban areas of the Brazilian Amazon and to investigate the bacterial diversity associated with abdomen of Ny. darlingi and Nyssorhynchus braziliensis. Methods - Mosquito collections were carried out in rural and peri-urban areas of the Brazilian Amazon. Detection tests for Plasmodium spp. mosquitoes were carried out. Correlation and regression analyzes were performed between landscape metrics and the following variables: cumulative incidence of malaria, number of Ny. darlingi, infected mosquitoes, and human biting rate. Sequencing of the V4 region of the 16S rRNA gene was performed to explore the bacterial diversity associated with abdomen of Ny. braziliensis and Ny. darlingi naturally infected and not infected by Plasmodium spp. Results - Nyssorhynchus darlingi, Nyssorhynchus rangeli, Nyssorhynchus benarrochi B and Nyssorhynchus konderi B were found infected with Plasmodium. Plasmodium vivax and Plasmodium falciparum were the parasite species found in the vectors. Positive correlations were found between cumulative incidence of malaria and the variables human biting rate, edge density and number of Ny. darlingi. Percentage of forest cover and human biting rate presented negative correlation. The period from 0 h: 00 to 3 h: 00 was the one with the highest number of infected mosquitoes. There was no statistical difference between bacterial diversity in Ny. darlingi infected and uninfected. Asaia and Serratia were present in both species of Nyssochynchus. Enterobacter was found only in abdomen of Ny. darlingi uninfected and Pseudomonas was the genus most abundant. Conclusion - This study reports for the first time the natural infection by Plasmodium in Ny. konderi B and Ny. benarrochi B in regions of the Brazilian Amazon. The results suggest that changes in the landscape can favor the occurrence of new vectors and, consequently, increase the number of malaria cases in endemic regions. The finding of a greater number of infected mosquitoes after midnight contributes to vector control measures and confirms the importance of insecticide-treated nets. The presence of Asaia and Serratia in both species of Nyssorhynchus and the high prevalence of Pseudomonas in Ny. darlingi indicate the need for further studies on the possible use of these bacteria in the control of malaria through paratransgenesis. The presence of the Enterobacter only in abdomen Ny. darlingi uninfected suggests that bacteria of this genus can offer protection to Plasmodium infection and other studies should be performed to verify this hypothesis.


Subject(s)
Plasmodium , Rural Areas , Amazonian Ecosystem , Malaria , Anopheles
10.
Article in English | WPRIM | ID: wpr-760353

ABSTRACT

Avian malaria is one of the most important general blood parasites of poultry in Southeast Asia. Plasmodium (P.) juxtanucleare causes avian malaria in wild and domestic fowl. This study aimed to identify and characterize the Plasmodium species infecting in Thai native fowl. Blood samples were collected for microscopic examination, followed by detection of the Plasmodium cox I gene by using PCR. Five of the 10 sampled fowl had the desired 588 base pair amplicons. Sequence analysis of the five amplicons indicated that the nucleotide and amino acid sequences were homologous to each other and were closely related (100% identity) to a P. juxtanucleare strain isolated in Japan (AB250415). Furthermore, the phylogenetic tree of the cox I gene showed that the P. juxtanucleare in this study were grouped together and clustered with the Japan strain. The presence of P. juxtanucleare described in this study is the first report of P. juxtanucleare in the Thai native fowl of Thailand.


Subject(s)
Amino Acid Sequence , Animals , Asia, Southeastern , Asians , Base Pairing , Cytochromes c , Cytochromes , Electron Transport Complex IV , Humans , Japan , Malaria, Avian , Parasites , Plasmodium , Polymerase Chain Reaction , Poultry , Sequence Analysis , Thailand , Trees
11.
Article in English | WPRIM | ID: wpr-761779

ABSTRACT

Plasmodium vivax is usually considered morbidity in endemic areas of Asia, Central and South America, and some part of Africa. In Thailand, previous studies indicated the genetic diversity of P. vivax in malaria-endemic regions such as the western part of Thailand bordering with Myanmar. The objective of the study is to investigate the genetic diversity of P. vivax circulating in Southern Thailand by using 3 antigenic markers and 8 microsatellite markers. Dried blood spots were collected from Chumphon, Phang Nga, Ranong and, Surat Thani provinces of Thailand. By PCR, 3 distinct sizes of PvMSP3α, 2 sizes of PvMSP3β and 2 sizes of PvMSP1 F2 were detected based on the length of PCR products, respectively. PCR/RFLP analyses of these antigen genes revealed high levels of genetic diversity. The genotyping of 8 microsatellite loci showed high genetic diversity as indicated by high alleles per locus and high expected heterozygosity (H(E)). The genotyping markers also showed multiple-clones of infection. Mixed genotypes were detected in 4.8% of PvMSP3α, 29.1% in PvMSP3β and 55.3% of microsatellite markers. These results showed that there was high genetic diversity of P. vivax isolated from Southern Thailand, indicating that the genetic diversity of P. vivax in this region was comparable to those observed other areas of Thailand.


Subject(s)
Africa , Alleles , Asia, Central , Genetic Variation , Genotype , Malaria , Microsatellite Repeats , Myanmar , Plasmodium vivax , Plasmodium , Polymerase Chain Reaction , South America , Thailand
12.
Article in English | WPRIM | ID: wpr-761762

ABSTRACT

Artemisinin-based combination therapy (ACT) resistance is widespread throughout the Greater Mekong Subregion. This raises concern over the antimalarial treatment in Thailand since it shares borders with Cambodia, Laos, and Myanmar where high ACT failure rates were reported. It is crucial to have information about the spread of ACT resistance for efficient planning and treatment. This study was to identify the molecular markers for antimalarial drug resistance: Pfkelch13 and Pfmdr1 mutations from 5 provinces of southern Thailand, from 2012 to 2017, of which 2 provinces on the Thai- Myanmar border (Chumphon and Ranong), one on Thai-Malaysia border (Yala) and 2 from non-border provinces (Phang Nga and Surat Thani). The results showed that C580Y mutation of Pfkelch13 was found mainly in the province on the Thai-Myanmar border. No mutations in the PfKelch13 gene were found in Surat Thani and Yala. The Pfmdr1 gene isolated from the Thai-Malaysia border was a different pattern from those found in other areas (100% N86Y) whereas wild type strain was present in Phang Nga. Our study indicated that the molecular markers of artemisinin resistance were spread in the provinces bordering along the Thai-Myanmar, and the pattern of Pfmdr1 mutations from the areas along the international border of Thailand differed from those of the non-border provinces. The information of the molecular markers from this study highlighted the recent spread of artemisinin resistant parasites from the endemic area, and the data will be useful for optimizing antimalarial treatment based on regional differences.


Subject(s)
Cambodia , Drug Resistance , Laos , Myanmar , Parasites , Plasmodium falciparum , Plasmodium , Thailand
13.
Article in English | WPRIM | ID: wpr-761732

ABSTRACT

Both Plasmodium spp. and Toxoplasma gondii are important apicomplexan parasites, which infect humans worldwide. Genetic analyses have revealed that 33% of amino acid sequences of inner membrane complex from the malaria parasite Plasmodium berghei is similar to that of Toxoplasma gondii. Inner membrane complex is known to be involved in cell invasion and replication. In this study, we investigated the resistance against T. gondii (ME49) infection induced by previously infected P. berghei (ANKA) in mice. Levels of T. gondii-specific IgG, IgG1, IgG2a, and IgG2b antibody responses, CD4+ and CD8+ T cell populations were found higher in the mice infected with P. berghei (ANKA) and challenged with T. gondii (ME49) compared to that in control mice infected with T. gondii alone (ME49). P. berghei (ANKA) + T. gondii (ME49) group showed significantly reduced the number and size of T. gondii (ME49) cysts in the brains of mice, resulting in lower body weight loss compared to ME49 control group. These results indicate that previous exposure to P. berghei (ANKA) induce resistance to subsequent T. gondii (ME49) infection.


Subject(s)
Amino Acid Sequence , Animals , Antibody Formation , Body Weight , Brain , Humans , Immunoglobulin G , Malaria , Membranes , Mice , Parasites , Plasmodium berghei , Plasmodium , Toxoplasma , Toxoplasmosis
14.
Article in English | WPRIM | ID: wpr-761731

ABSTRACT

The pathogenesis of cerebral malaria is biologically complex and involves multi-factorial mechanisms such as microvascular congestion, immunopathology by the pro-inflammatory cytokine and endothelial dysfunction. Recent data have suggested that a pleiotropic T-cell immunomodulatory protein (TIP) could effectively mediate inflammatory cytokines of mammalian immune response against acute graft-versus-host disease in animal models. In this study, we identified a conserved homologue of TIP in Plasmodium berghei (PbTIP) as a membrane protein in Plasmodium asexual stage. Compared with PBS control group, the pathology of experimental cerebral malaria (ECM) in rPbTIP intravenous injection (i.v.) group was alleviated by the downregulation of pro-inflammatory responses, and rPbTIP i.v. group elicited an expansion of regulatory T-cell response. Therefore, rPbTIP i.v. group displayed less severe brain pathology and feverish mice in rPbTIP i.v. group died from ECM. This study suggested that PbTIP may be a novel promising target to alleviate the severity of ECM.


Subject(s)
Animals , Brain , Cytokines , Down-Regulation , Estrogens, Conjugated (USP) , Graft vs Host Disease , Injections, Intravenous , Malaria, Cerebral , Membrane Proteins , Mice , Models, Animal , Pathology , Plasmodium berghei , Plasmodium , Staphylococcal Protein A , T-Lymphocytes
15.
Article in English | WPRIM | ID: wpr-761730

ABSTRACT

Malarial infection induces tissue hypoxia in the host through destruction of red blood cells. Tissue hypoxia in malarial infection may increase the activity of HIF1α through an intracellular oxygen-sensing pathway. Activation of HIF1α may also induce vascular endothelial growth factor (VEGF) to trigger angiogenesis. To investigate whether malarial infection actually generates hypoxia-induced angiogenesis, we analyzed severity of hypoxia, the expression of hypoxia-related angiogenic factors, and numbers of blood vessels in various tissues infected with Plasmodium berghei. Infection in mice was performed by intraperitoneal injection of 2×10⁶ parasitized red blood cells. After infection, we studied parasitemia and survival. We analyzed hypoxia, numbers of blood vessels, and expression of hypoxia-related angiogenic factors including VEGF and HIF1α. We used Western blot, immunofluorescence, and immunohistochemistry to analyze various tissues from Plasmodium berghei-infected mice. In malaria-infected mice, parasitemia was increased over the duration of infection and directly associated with mortality rate. Expression of VEGF and HIF1α increased with the parasitemia in various tissues. Additionally, numbers of blood vessels significantly increased in each tissue type of the malaria-infected group compared to the uninfected control group. These results suggest that malarial infection in mice activates hypoxia-induced angiogenesis by stimulation of HIF1α and VEGF in various tissues.


Subject(s)
Angiogenesis Inducing Agents , Animals , Hypoxia , Blood Vessels , Blotting, Western , Erythrocytes , Fluorescent Antibody Technique , Immunohistochemistry , Injections, Intraperitoneal , Malaria , Mice , Mortality , Parasitemia , Plasmodium , Plasmodium berghei , Vascular Endothelial Growth Factor A
16.
Safety and Health at Work ; : 122-124, 2019.
Article in English | WPRIM | ID: wpr-761327

ABSTRACT

Simian malaria is a zoonotic disease caused by Plasmodium knowlesi infection. The common natural reservoir of the parasite is the macaque monkey and the vector is the Anopheles mosquito. Human cases of P. knowlesi infection has been reported in all South East Asian countries in the last decade, and it is currently the most common type of malaria seen in Malaysia and Brunei. Between 2007–2017, 73 cases of P. knowlesi infection were notified and confirmed to the Ministry of Health in Brunei. Of these, 15 cases (21%) were documented as work-related, and 28 other cases (38%) were classified as probably related to work (due to incomplete history). The occupations of those with probable and confirmed work related infections were border patrol officers, Armed Forces and security personnel, Department of Forestry officers, boatmen and researchers. The remaining cases classified as most likely not related to work were possibly acquired via peri-domestic transmission. The risk of this zoonotic infection extends to tourists and overseas visitors who have to travel to the jungle in the course of their work. It can be minimised with the recommended use of prophylaxis for those going on duty into the jungles, application of mosquito/insect repellants, and use of repellant impregnated uniforms and bed nets in jungle camp sites.


Subject(s)
Anopheles , Arm , Asians , Brunei , Culicidae , Forestry , Haplorhini , Humans , Macaca , Malaria , Malaysia , Occupations , Parasites , Plasmodium knowlesi , Plasmodium , Zoonoses
17.
Article in English | WPRIM | ID: wpr-719576

ABSTRACT

Mixed-species malaria infections are often unrecognized or underestimated. We hereby report the first described case of mixed infection with Plasmodium falciparum and Plasmodium ovale malaria in a returned traveller in Korea. In August 2016, a 25-year-old returned traveller from Cameroon and Democratic Republic of Congo presented with fever. He was diagnosed as P. falciparum malaria and successfully treated with artesunate. And 5 weeks after the completion of treatment, he presented with fever and diagnosed as P. ovale infection. P. ovale infection is a rare cause of malaria and often shows delayed presentation due to its dormant liver stage as hypnozoites. At re-presentation, the immunochromatographic test and microscopic examinations of our patient did not reveal P. ovale, which was only detected via polymerase chain reaction (PCR) assay. This case highlights the importance of considering malaria infection even in persons who have previously received malaria treatment. It also shows the usefulness of PCR testing for diagnosing P. ovale infections, which often present with a low level of parasitaemia.


Subject(s)
Adult , Cameroon , Coinfection , Congo , Fever , Humans , Korea , Liver , Malaria , Plasmodium falciparum , Plasmodium ovale , Plasmodium , Polymerase Chain Reaction
18.
Rev. bras. parasitol. vet ; 27(3): 363-376, July-Sept. 2018. tab, graf
Article in English | LILACS, SES-SP | ID: biblio-959200

ABSTRACT

Abstract The aim of this study was to identify Plasmodium spp. in blood samples from nonhuman primates (NHPs) in the state of Maranhão, using classical and alternative techniques for examination of human malaria. A total of 161 blood samples from NHPs were analyzed: 141 from captive animals at a Wildlife Screening Center (CETAS) and 20 from free-living animals in a private reserve. The techniques used were microscopy, rapid diagnostic test (RDT), Indirect fluorescent antibody test (IFAT) and molecular techniques (semi-nested PCR, quantitative real-time PCR and LAMP). Two serological methods (dot-ELISA and indirect ELISA) were also standardized with rhoptry protein-soluble antigen of P. falciparum and P. berghei. Trophozoite forms of Plasmodium sp. were identified on slides from five different animals. No samples were positive through RDT and LAMP. Four samples were seropositive for P. malariae through IFAT. The samples showed low reactivity to ELISA. Plasmodium sp. was detected in 34.16% (55/161) of the samples using qPCR based on the 18S rRNA gene. After sequencing, two samples showed 100% identityl to P. malariae, one showed 97% identity to Plasmodium sp. ZOOBH and one showed 99% identity to P. falciparum . PCR was shown to be the most sensitive technique for diagnosing Plasmodium in NHP samples.


Resumo Neste estudo objetivamos identificar Plasmodium spp. em amostras sangue de primatas não humanos (PNH) do estado do Maranhão, utilizando técnicas clássicas e alternativas para o exame da malária humana. Foram analisadas 161 amostras de sangue de PNH, sendo 141 de CETAS (cativeiro) e 20 de reserva particular (vida livre), utilizando microscopia, teste de diagnóstico rápido (RDT), imunofluorescência indireta (IFI) e técnicas moleculares (semi-nested PCR, PCR em tempo real quantitativo e LAMP). Dois métodos sorológicos (dot-ELISA e ELISA indireto) também foram padronizados com antígenos solúveis de roptrias de P. falciparum e P. berghei. Formas trofozoíticas de Plasmodium sp. foram identificadas em lâminas de cinco animais diferentes. Nenhuma amostra foi positiva em TDR e LAMP. Quatro amostras foram soropositivas para P. malariae na IFI. Os soros de PNH mostraram baixa reatividade pelo ELISA indireto. Plasmodium sp. foi detectado em 34,16% (55/161) das amostras utilizando a qPCR baseada no gene 18S rRNA. No sequenciamento, duas amostras mostraram identidade com P. malariae (100%), uma com Plasmodium sp. ZOOBH (97%) e uma com P. falciparum (99%). A PCR mostrou ser a técnica mais sensível para diagnósticos de Plasmodium em amostras de PNH.


Subject(s)
Animals , Male , Plasmodium/genetics , Plasmodium/immunology , Platyrrhini/parasitology , Malaria/veterinary , Antibodies, Protozoan/blood , RNA, Ribosomal, 18S/blood , DNA, Protozoan/blood , Fluorescent Antibody Technique, Indirect , Real-Time Polymerase Chain Reaction , Malaria/diagnosis , Malaria/parasitology
19.
Rev. biol. trop ; 66(2): 880-891, abr.-jun. 2018. graf
Article in English | LILACS, SaludCR | ID: biblio-977352

ABSTRACT

Abstract Malaria represents a major health problem worldwide, affecting around 198 million people in 2016 according to WHO database. For decades, anti-malarial drug therapy has been used in the battle against this disease and its uncontrolled usage in endemic areas has developed the appearance of the drug resistance. Thus, it has emerged the necessity of finding new treatments that could be used as an alternative cure to malaria infection. The aim of this work was the evaluation of two photo-excitable compounds: Compound 1, which is (2E)-3-(4-dimethylamino-phenyl)-1-(4-imidazol-1-yl-phenyl)prop-2-en-1-one) and Compound 2, (1E,4E)1-[4-(dimethylamino)phenyl]-5-(4-methoxyphenyl)-1,4-pentadiene-3-one) as possible anti-malaria drugs with Plasmodium berghei ANKA strain in BALB/c mice as murine model. Cytotoxicity effect was evaluated by a cell proliferation by colorimetry assay (MTS); and the drug incorporation into the parasite was assessed in vitro with Indirect Immunofluorescence Assay (IFA) to determine the localization of the drugs into the parasitized red blood cells (RBCs). Finally, the curative effect of compounds no-radiation (fundamental state) and ration drugs were evaluated by oral drug administration of this drugs in BALB/c mice and chloroquine was used as positive control. This curative effect was determined daily by the parasitemia percentage. The results showed that both compounds were cytotoxic in fundamental state. Furthermore, cytotoxic effect was increased after radiation into the Solar Simulator, and compound 2 was more cytotoxic than compound 1. Curative assays showed that both compounds in fundamental state were non effective as anti-malarial drug. However, in the curative assays in the mice treated with compound 2, when this was ration showed a survival rate of 33 % and a parasitemia percentage decrease in compare to compound 1. Although the compounds did not show a similar or better anti-malarial effect than Chloroquine, Compound 2 presented certain anti-malarial effect after solar radiation. Rev. Biol. Trop. 66(2): 880-891. Epub 2018 June 01.


Resumen La malaria representa un importante problema de salud en todo el mundo, afectando a alrededor de 198 millones de personas en 2016 según la base de datos de la OMS. Durante décadas, se ha utilizado la terapia con fármacos anti-malpricos en la lucha contra esta enfermedad y su uso incontrolado en las zonas endémicas ha desarrollado la aparición de resistencia a los fármacos. Por lo tanto, se ha surgido la necesidad de encontrar nuevos tratamientos que podrían ser utilizados como una cura alternativa para la infección por el paludismo. El objetivo de este trabajo fue evaluar dos compuestos foto-excitables: El compuesto 1, que es (2E) -3- (4-dimetilamino-fenil) -1- (4-imidazol-1-ilfenil) prop-2 1-ona) y el Compuesto 2, (1E, 4E) -1- [4- (dimetilamino) fenil] -5- (4-metoxifenil) -1,4-pentadieno-3-ona) como posibles drogas antimaláricas con la cepa ANKA de Plasmodium berghei en ratones BALB / c como modelo murino. El efecto de la citotoxicidad se evaluó mediante una proliferación celular con el ensayo de colorimetría (MTS); y la incorporación del fármaco en el parásito se evaluó in vitro con Ensayo de Inmunofluorescencia Indirecta (IFA) para determinar la localización de los fármacos en los glóbulos rojos parasitados (RBCs). Finalmente, se evaluó el efecto curativo de los compuestos sin radiación (estado fundamental) y los fármacos irradiados mediante la administración oral de los fármacos en los ratones BALB / c, y se usó cloroquina como control positivo de cura. Este efecto curativo se determinó diariamente por el porcentaje de parasitemia. Los resultados mostraron que ambos compuestos eran citotóxicos en estado fundamental. Además, el efecto citotóxico se incrementó después de la radiación en el Simulador Solar, y el compuesto 2 fue más citotóxico que el compuesto 1. Los ensayos curativos mostraron que ambos compuestos en estado fundamental no eran eficaces como fármacos antimaláricos. Sin embargo, en los ensayos curativos en los ratones tratados con el compuesto 2, cuando fue irradiado, se observó una tasa de supervivencia del 33 % y una disminución del porcentaje de parasitemia en comparación con el compuesto 1. Aunque los compuestos no mostraron un efecto similar o mejor antimalárico que la cloroquina, el compuesto 2 presentó cierto efecto antimalárico después de la radiación solar.


Subject(s)
Animals , Plasmodium/drug effects , Dimethylamines/pharmacology , Imidazoles/therapeutic use , Malaria/drug therapy , Solar Radiation
20.
Salud pública Méx ; 60(1): 77-85, Jan.-Feb. 2018. tab, graf
Article in English | LILACS | ID: biblio-903841

ABSTRACT

Abstract: Objective: To analyze the current knowledge of pathogen-insect interactions amenable for the design of molecular-based control strategies of vector-borne diseases. Materials and methods: We examined malaria, dengue, and Chagas disease pathogens and insect molecules that participate in interactions during their vectors infection. Results: Pathogen molecules that participate in the insect intestine invasion and induced vector immune molecules are presented, and their inclusion in transmission blocking vaccines (TBV) and in genetically modify insect (GMI) vectors or symbiotic bacteria are discussed. Conclusion: Disruption of processes by blocking vector-pathogen interactions provides several candidates for molecular control strategies, but TBV and GMI efficacies are still limited and other secondary effects of GMI (improving transmission of other pathogens, affectation of other organisms) should be discarded.


Resumen: Objetivo: Analizar el conocimiento actual de las interacciones patógeno-insecto susceptibles a incluirse en el diseño de estrategias moleculares para el control de enfermedades transmitidas por vectores. Material y métodos: Se examinaron los agentes causales de la malaria, el dengue y la enfermedad de Chagas, y las moléculas de insectos que participan en interacciones durante la infección de sus vectores. Resultados: Se presentan moléculas de patógenos que participan en la invasión del intestino del insecto y moléculas inmunes inducidas en los vectores. Se discute su inclusión en vacunas bloqueadoras de transmisión (VBT) y en la modificación genética de vectores (MGI) o de sus bacterias simbióticas. Conclusión: La interrupción de procesos mediante el bloqueo de las interacciones patógeno-vector proporciona varios candidatos para las estrategias de control molecular, pero la eficacia de VBT y MGI es aún limitada y los efectos secundarios de MGI (aumento de la transmisión de otros patógenos y afectación de otros organismos) deben descartase.


Subject(s)
Animals , Insect Control/methods , Chagas Disease/prevention & control , Dengue/prevention & control , Dengue Virus/physiology , Host-Pathogen Interactions/genetics , Malaria/prevention & control , Plasmodium/physiology , Trypanosoma cruzi/physiology , Aedes/genetics , Reduviidae/genetics , Reduviidae/virology , Mosquito Vectors/genetics , Anopheles/genetics
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