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1.
Cytokine ; 147: 155309, 2021 11.
Article in English | MEDLINE | ID: mdl-33334669

ABSTRACT

Macrophages are host cells for parasites of the genus Leishmania where they multiply inside parasitophorous vacuoles. Paradoxically, macrophages are also the cells responsible for killing or controlling parasite growth, if appropriately activated. In this review, we will cover the patterns of macrophage activation and the mechanisms used by the parasite to circumvent being killed. We will highlight the impacts of the vector bite on macrophage activation. Finally, we will discuss the ontogeny of macrophages that are infected by Leishmania spp.


Subject(s)
Cytokines/metabolism , Leishmaniasis/metabolism , Leishmaniasis/parasitology , Macrophages/metabolism , Macrophages/parasitology , Animals , Humans , Leishmania/pathogenicity , Macrophage Activation/physiology
2.
Braz. j. biol ; 76(2): 334-340, Apr.-June 2016. tab, graf
Article in English | LILACS | ID: lil-781388

ABSTRACT

Abstract The aim of this study was to monitor the population density of Lymnaea columella, an intermediate host of Fasciola hepatica, in various aquatic habitats and in drinking water in the area of the Instituto Federal de Educação, Ciência e Tecnologia do Espírito Santo, on Caparaó Microregion, municipality of Alegre, state of Espírito Santo, Brazil. Monthly samplings were performed at certain points between drainage areas and drinking water in cattle and goat production systems during the years 2010 to 2013. The mean temperature, precipitation and the frequency of samples of L. columella were analysed graphically according the monthly average during the study period. A total of 2,038 molluscs were collected, 1558 of which were L. columella, that predominated in all sampled points. The highest average of specimens observed for L. columella was in the years 2010 and 2013 (51.0), and occurred decreased in 2011 (19.8). The temperature and precipitation averaged is 23.7 °C and 141 mm/year, respectively. Rainfall peak occurred in March (2011, 2013) and November (2012), during these periods the population of L. columella growth. There was no significant difference in the relationship between the specimens observed with seasons (dry-wet), thus the population of L. columella remained stable and can be found throughout the year.


Resumo O objetivo deste estudo foi acompanhar a variação da densidade populacional de Lymnaea columella, hospedeiro intermediário de Fasciola hepatica, em diferentes tipos de coleções hídricas e bebedouros na área do Instituto Federal de Educação, Ciência e Tecnologia do Espírito Santo, na microrregião do Caparaó, município de Alegre, estado do Espírito Santo, Brasil. Foram realizadas coletas mensais em pontos determinados entre áreas de drenagem e bebedouros de animais nos setores de bovinocultura e caprinocultura durante os anos de 2010 a 2013. As médias de temperatura, precipitação e a frequência de exemplares de L. columella foram analisadas graficamente de acordo com a média mensal ao longo do período avaliado. Foram coletados 2.038 moluscos, sendo 1558 de L. columella, espécie predominante em todos os pontos amostrados. A maior média de espécimes observadas para L. columella foi nos anos de 2010 e 2013 (51,0), ocorrendo um decréscimo em 2011 (19,8). A temperatura apresentou média de 23,7°C e precipitação de 141 mm/ano. Picos de precipitação ocorreram em Março (2011, 2013) e Novembro (2012), nestes períodos foi observado aumento populacional de L. columella. Não houve diferença significativa na relação entre as espécimes observadas com as estações do ano (seca-chuvosa), dessa forma, a população de L. columella se mostrou estável, podendo ser encontrada durante todo ano.


Subject(s)
Animals , Food Chain , Fasciola hepatica/physiology , Lymnaea/physiology , Seasons , Drinking Water/analysis , Drinking Water/parasitology , Brazil , Cattle , Goats , Population Density , Ecological and Environmental Phenomena , Hydrobiology/methods , Host-Parasite Interactions , Animal Husbandry/methods
3.
Braz J Biol ; 76(2): 334-40, 2016 Jun.
Article in English | MEDLINE | ID: mdl-26934156

ABSTRACT

The aim of this study was to monitor the population density of Lymnaea columella, an intermediate host of Fasciola hepatica, in various aquatic habitats and in drinking water in the area of the Instituto Federal de Educação, Ciência e Tecnologia do Espírito Santo, on Caparaó Microregion, municipality of Alegre, state of Espírito Santo, Brazil. Monthly samplings were performed at certain points between drainage areas and drinking water in cattle and goat production systems during the years 2010 to 2013. The mean temperature, precipitation and the frequency of samples of L. columella were analysed graphically according the monthly average during the study period. A total of 2,038 molluscs were collected, 1558 of which were L. columella, that predominated in all sampled points. The highest average of specimens observed for L. columella was in the years 2010 and 2013 (51.0), and occurred decreased in 2011 (19.8). The temperature and precipitation averaged is 23.7 °C and 141 mm/year, respectively. Rainfall peak occurred in March (2011, 2013) and November (2012), during these periods the population of L. columella growth. There was no significant difference in the relationship between the specimens observed with seasons (dry-wet), thus the population of L. columella remained stable and can be found throughout the year.


Subject(s)
Fasciola hepatica/physiology , Food Chain , Lymnaea/physiology , Animal Husbandry/methods , Animals , Brazil , Cattle , Drinking Water/analysis , Drinking Water/parasitology , Ecological and Environmental Phenomena , Goats , Host-Parasite Interactions , Hydrobiology/methods , Population Density , Seasons
4.
Parasite Immunol ; 38(1): 37-44, 2016 Jan.
Article in English | MEDLINE | ID: mdl-26407073

ABSTRACT

Animals are colonized by their indigenous microbiota from the early days of life. The estimated number of associated bacterial cells in humans is around of 10(14) per individual, most of them in the gut. Several studies have investigated the microbiota-host relationship, and the use of germfree animals has been an important tool in these studies. These animals, when infected with a pathogen, have shown to be sometimes more resistant and other times more susceptible than conventional animals. Leishmaniasis is a worldwide public health problem and presents a spectrum of clinical manifestations. However, very few studies have addressed the role of the indigenous microbiota on the outcome of this disease. In this review, we will highlight and discuss the data available on the ways by which the microbiota can influence the outcome of the disease in murine experimental models of cutaneous infection with Leishmania.


Subject(s)
Bacteria/immunology , Leishmania major/immunology , Leishmaniasis/immunology , Microbiota/immunology , Animals , Germ-Free Life , Humans , Leishmaniasis/parasitology , Mice
5.
Parasite Immunol ; 36(1): 13-31, 2014 Jan.
Article in English | MEDLINE | ID: mdl-24102495

ABSTRACT

Neutrophils are involved in the early stages of immune responses to pathogens. Here, we investigated the role of neutrophils during the establishment of Leishmania amazonensis infection in BALB/c and C57BL/6 mice. First, we showed an accumulation of neutrophils between 6 and 24 h post-infection, followed by a reduction in neutrophil numbers after 72 h. Next, we depleted neutrophils prior to infection using RB6-8C5 or 1A8 mAb. Neutrophil depletion led to faster lesion development, increased parasite numbers and higher arginase activity during the first week of infection in BALB/c mice, but not in C57BL/6 mice. Increased susceptibility was accompanied by augmented levels of anti-L. amazonensis IgG and increased production of IL-10 and IL-17. Because IL-10 is a mediator of susceptibility to Leishmania infection, we blocked IL-10 signalling in neutrophil-depleted mice using anti-IL-10R. Interestingly, inhibition of IL-10 signalling abrogated the increase in parasite loads observed in neutrophil-depleted mice, suggesting that parasite proliferation is at least partially mediated by IL-10. Additionally, we tested the effect of IL-17 in inflammatory macrophages and observed that IL-17 increased arginase activity and favoured parasite growth. Taken together, our data indicate that neutrophils control parasite numbers and limit lesion development during the first week of infection in BALB/c mice.


Subject(s)
Leishmania mexicana/growth & development , Leishmania mexicana/immunology , Leishmaniasis, Cutaneous/immunology , Leishmaniasis, Cutaneous/parasitology , Neutrophils/immunology , Animals , Antibodies, Protozoan/blood , Arginase/metabolism , Female , Immunoglobulin G/blood , Interleukin-10/metabolism , Interleukin-17/metabolism , Kinetics , Macrophage Activation , Macrophages/immunology , Macrophages/metabolism , Macrophages/parasitology , Mice , Mice, Inbred BALB C , Mice, Inbred C57BL , Neutrophil Infiltration , Parasite Load , T-Lymphocytes, Regulatory/immunology
6.
J Mater Sci Mater Med ; 23(7): 1785-96, 2012 Jul.
Article in English | MEDLINE | ID: mdl-22569732

ABSTRACT

This study assess the effects of bioceramic and poly(lactic-co-glycolic acid) composite (BCP/PLGA) on the viability of cultured macrophages and human dental pulp fibroblasts, and we sought to elucidate the temporal profile of the reaction of pulp capping with a composite of bioceramic of calcium phosphate and biodegradable polymer in the progression of delayed dentine bridge after (30 and 60 days) in vivo. Histological evaluation of inflammatory infiltrate and dentin bridge formation were performed after 30 and 60 days. There was similar progressive fibroblast growth in all groups and the macrophages showed viability. The in vivo study showed that of the three experimental groups: BCP/PLGA composite, BCP and calcium hydroxide (Ca(OH)(2)) dentin bridging was the most prevalent (90 %) in the BCP/PLGA composite after 30 days, mild to moderate inflammatory response was present throughout the pulp after 30 days. After 60 days was observed dentine bridging in 60 % and necrosis in 40 %, in both groups. The results indicate that understanding BCP/PLGA composite is biocompatible and by the best tissue response as compared to calcium hydroxide in direct pulp capping may be important in the mechanism of delayed dentine bridge after 30 and 60 days.


Subject(s)
Biocompatible Materials , Calcium Phosphates/administration & dosage , Lactic Acid/administration & dosage , Polyglycolic Acid/administration & dosage , Cells, Cultured , Humans , In Vitro Techniques , Microscopy, Electron, Scanning , Polylactic Acid-Polyglycolic Acid Copolymer
7.
J. venom. anim. toxins incl. trop. dis ; 17(3): 271-276, 2011. mapas, tab
Article in English | LILACS | ID: lil-597225

ABSTRACT

Fasciolosis is a disease that affects the liver parenchyma and bile ducts of numerous animals, including humans, which causes economic losses and threatens public health. The present work aimed at reporting the distribution and factors connected with Fasciola hepatica infection in cattle in ten municipalities in southern Espírito Santo, Brazil, between 2008 and 2009. During this period, 50 rural properties in ten cities were analyzed and fecal samples from 10 percent of the cattle on each farm were collected. Of the 717 samples analyzed, 154 (21.33 percent) presented Fasciola hepatica eggs. As for the 50 rural properties studied, 32 (64 percent) had animals positive for fasciolosis. Throughout the evaluation, it was observed that 42 (84 percent) rural properties had flooded areas, 33 (66 percent) were located at altitudes less than 226 meters, in 36 (72 percent) mollusks were found, 47 (94 percent) had other definitive hosts (horses, sheep, goats) and 25 (50 percent) had previous cases of bovine fasciolosis. The present results showed a high rate of bovine fasciolosis in the analyzed region whereas infected animals are present in all the municipalities. Based on statistical analysis, it was concluded that there was an association between the presence of flooded areas and other definitive hosts in rural properties where bovine fasciolosis was detected.


Subject(s)
Animals, Domestic/parasitology , Fascioliasis/diagnosis , Fascioliasis/epidemiology
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