Abstract:
:Toxoplasma gondii, the agent of toxoplasmosis, is an intracellular parasite that can infect a wide range of vertebrate hosts. Toxoplasmosis causes severe damage to immunocompromised hosts and its treatment is mainly based on the combination of pyrimethamine and sulfadiazine, which causes relevant side effects primarily observed in AIDS patients, including bone marrow suppression and hematological toxicity (pyrimethamine) and/or hypersensitivity and allergic skin reactions (sulfadiazine). Thus, it is important to investigate new compounds against T. gondii, particularly those that may act on bradyzoites, which are present in cysts during the chronic disease phase. We propose an in vitro model to simultaneously study new candidate compounds against the two main causative stages of Toxoplasma infection in humans, using the EGS-DC strain that was modified from a type I/III strain (EGS), isolated from a case of human congenital toxoplasmosis in Brazil and engineered to express markers for both stages of development. One feature of this strain is that it presents tachyzoite and bradyzoite in the same culture system and in the same host cell under normal culture conditions. Additionally, this strain presents stage-specific fluorescent protein expression, allowing for easy identification of both stages, thus making this strain useful in different studies. HFF cells were infected and after 4 and 7 days post infection the cells were treated with 10 μM of pyrimethamine or atovaquone, for 48 or 72 h. We used high-throughput screening to quantify the extent of parasite infection. Despite a reduction in tachyzoite infection caused by both treatments, the atovaquone treatment reduced the bradyzoite infection while the pyrimethamine one increased it. Ultrastructural analysis showed that after treatment with both drugs, parasites displayed altered mitochondria. Fluorescence microscopy of cells labeled with MitoTracker CMXRos showed that the cysts present inside the cells lost their mitochondrial membrane potential. Our results indicate that this experimental model is adequate to simultaneously analyze new active compounds against tachyzoite and bradyzoite forms.
journal_name
Parasitol Resjournal_title
Parasitology researchauthors
Portes JA,De Souza Wdoi
10.1007/s00436-019-06493-6subject
Has Abstractpub_date
2019-12-01 00:00:00pages
3479-3489issue
12eissn
0932-0113issn
1432-1955pii
10.1007/s00436-019-06493-6journal_volume
118pub_type
杂志文章abstract::Although miltefosine (MIL) has only recently been positioned as a first-line therapeutic option for visceral leishmaniasis, field reports note an increasing trend in treatment failures. Study of laboratory selected MIL-resistant strains is needed in the absence of confirmed resistant clinical isolates. In contrast to ...
journal_title:Parasitology research
pub_type: 杂志文章
doi:10.1007/s00436-015-4460-9
更新日期:2015-07-01 00:00:00
abstract::Ingestion of the larval nematode Angiostrongylus cantonensis can cause the human eosinophilic meningitis known as angiostrongyliasis. Analysis of the extracts and excretory-secretory (ES) products of A. cantonensis larvae and adult stages on gelatin substrate zymography demonstrated the presence of distinct gelatinoly...
journal_title:Parasitology research
pub_type: 杂志文章
doi:10.1007/s00436-005-1484-6
更新日期:2005-12-01 00:00:00
abstract::This study is focused on the feasibility of two treatments of alcohol-fixed monogenean parasites which are intended to be use for the combined morphological and molecular characterizations. The monogenean parasite, Eudiplozoon nipponicum, was selected as a model parasite species; however it is expected that these tech...
journal_title:Parasitology research
pub_type: 杂志文章
doi:10.1007/s00436-010-1949-0
更新日期:2010-09-01 00:00:00
abstract::A molecular phylogenetic hypothesis is presented for the genus Trichuris based on sequence data from mitochondrial cytochrome c oxidase 1 (cox1) and cytochrome b (cob). The taxa consisted of nine populations of whipworm from five species of Sigmodontinae rodents from Argentina. Bayesian Inference, Maximum Parsimony, a...
journal_title:Parasitology research
pub_type: 杂志文章
doi:10.1007/s00436-016-5045-y
更新日期:2016-08-01 00:00:00
abstract::The distribution of actin filaments in the spermatogenic cells of Fasciola hepatica was determined using a fluorescent derivative of phalloidin. Actin was localised primarily in the region of separation of a secondary spermatogonium from a primary spermatogonium, in the inner faces at the centre of four-cell clusters ...
journal_title:Parasitology research
pub_type: 杂志文章
doi:10.1007/BF00935425
更新日期:1991-01-01 00:00:00
abstract::Studies were conducted in Mwea Rice Scheme, Kenya during the period April 2005 and January 2007 to determine the host-feeding pattern of culicine mosquitoes. Mosquitoes were collected indoors and outdoors and tested for human, bovine, goat, and donkey blood meals by an Enzyme-Linked Immunosorbent Assay. A total of 1,7...
journal_title:Parasitology research
pub_type: 杂志文章
doi:10.1007/s00436-008-0914-7
更新日期:2008-05-01 00:00:00
abstract::Investigations by scanning and transmission electron microscopy and freeze-etching revealed that eyes of adult Rhipicephalus evertsi mimeticus consist of a lens and photoreceptor cells, which are separated by an acellular layer and the hypodermis. The lens contains numerous pore channels, which open beneath the epicut...
journal_title:Parasitology research
pub_type: 杂志文章
doi:10.1007/BF00933552
更新日期:1990-01-01 00:00:00
abstract::A study has been carried out to investigate whether the action of triclabendazole (TCBZ) against Fasciola hepatica is altered by inhibition of drug metabolism. The cytochrome P450 (CYP 450) enzyme pathway was inhibited using ketoconazole (KTZ) to see whether a TCBZ-resistant isolate could be made more sensitive to TCB...
journal_title:Parasitology research
pub_type: 更正并重新发布的文章,杂志文章
doi:10.1007/s00436-011-2554-6
更新日期:2011-10-01 00:00:00
abstract::Systematic, continuous mosquito surveillance is considered the most reliable tool to predict the spread and establishment of alien mosquito species such as the Asian tiger mosquito (Aedes albopictus), Japanese bush mosquito (Aedes japonicus), and the transmission risk of mosquito-borne arboviruses to humans. Only sing...
journal_title:Parasitology research
pub_type: 杂志文章
doi:10.1007/s00436-019-06287-w
更新日期:2019-05-01 00:00:00
abstract::During our investigations on helminthofauna in roe deer (Capreolus capreolus) and red deer (Cervus elaphus) in France (1985-1998) we isolated nematodes not only of the genus Haemonchus Cobb, 1898 but also of the genus Ashworthius Le Roux 1930, both of which belong to the same subfamily of Haemonchinae. The prevalence ...
journal_title:Parasitology research
pub_type: 杂志文章
doi:10.1007/pl00008534
更新日期:2000-07-01 00:00:00
abstract::The relationships between inflammation in organs with Toxocara canis larval migration and matrix metalloproteinase-9 (MMP-9) were investigated following the infection of mice with 1,000 infective eggs. Gelatinase activity was defined by gelatin zymography, optimum pH, inhibitor specificity and Western blot analysis. M...
journal_title:Parasitology research
pub_type: 杂志文章
doi:10.1007/s00436-004-1271-9
更新日期:2005-02-01 00:00:00
abstract::The chemotherapy of visceral leishmaniasis (VL) has several limitations including resistance and toxicity of the existing drugs. Downregulation of immune system further aggravates the problems. To combat this situation, leishmanicidal efficacy of already marketed standard antifungal drug, fluconazole under the approac...
journal_title:Parasitology research
pub_type: 杂志文章
doi:10.1007/s00436-010-2230-2
更新日期:2011-04-01 00:00:00
abstract::The efficacies of 20 mg/kg body weight (BW) of toltrazuril (Toltra) 2 days post-infection (dpi), 2 mg/kg BW of diclazuril 2 and 3 dpi and 200 mg/kg BW of sulphadimidine 2, 3 and 4 dpi were compared in a model for piglet isosporosis. Weight gain (first 4 weeks of life) and diarrhoea and oocyst excretion from 4 to 11 dp...
journal_title:Parasitology research
pub_type: 杂志文章,随机对照试验
doi:10.1007/s00436-006-0314-9
更新日期:2007-01-01 00:00:00
abstract::Genome analysis of Entamoeba histolytica predicts the presence of acetyl-CoA carboxylase. Using Western blot, histochemistry, and confocal microscopy, we demonstrated the presence of a biotin-containing protein in the cytoplasm of E. histolytica, with a molecular weight of 136 kDa and biotin-carboxylase activity. This...
journal_title:Parasitology research
pub_type: 杂志文章
doi:10.1007/s00436-012-2898-6
更新日期:2012-09-01 00:00:00
abstract::Infections with the metastrongyloid nematode Aelurostrongylus abstrusus in cats have been reported sporadically from Germany. To assess the occurrence and regional geographical distribution of A. abstrusus in Germany, faecal samples from 391 cats with symptoms of respiratory disease were collected from December 2009 t...
journal_title:Parasitology research
pub_type: 杂志文章
doi:10.1007/s00436-012-3207-0
更新日期:2013-02-01 00:00:00
abstract::Three juvenile nematode parasites were collected naturally from 90 (75 %) out of 120 specimens of the marine greater lizard fish Saurida undosquamis captured from water coasts at Hurghada City along the Red Sea in Egypt during the period from September 2013 to April 2014. Worms were identified on the basis of light an...
journal_title:Parasitology research
pub_type: 杂志文章
doi:10.1007/s00436-014-4285-y
更新日期:2015-03-01 00:00:00
abstract::Three monoclonal antibodies generated by immunization of mice with Plasmodium berghei-infected red blood cells were found to react with the 75-kDa heat-shock protein (HSP70) present in liver stages and erythrocytic forms of the parasites. These antibodies were shown to react with a recombinant protein encoding the car...
journal_title:Parasitology research
pub_type: 杂志文章
doi:10.1007/BF00932618
更新日期:1994-01-01 00:00:00
abstract::This study aims to observe the histopathological alterations in schistosomula of Schistosoma japonicum induced by mefloquine. Mice were infected with S. japonicum cercariae, and after 14 days, a single dose of mefloquine (400 mg/kg) was administered orally. After 8 h, 24 h, 3 days, 7 days, and 14 days, groups of two t...
journal_title:Parasitology research
pub_type: 杂志文章
doi:10.1007/s00436-009-1611-x
更新日期:2009-11-01 00:00:00
abstract::Human hydatidosis is characterized by a prolonged coexistence of Echinococcus granulosus and its host without effective rejection of the parasite. This parasitic infection constitutes a major health problem in Algeria. In this study, we investigated in vivo production of nitrite (NO(2)(-) + NO(3)(-)) in sera of Algeri...
journal_title:Parasitology research
pub_type: 杂志文章
doi:10.1007/s00436-012-3181-6
更新日期:2013-02-01 00:00:00
abstract::Spirocerca vulpis is a parasitic nematode of red foxes associated with gastric nodule formation. Since its description in 2018, this species has been reported in red foxes from Spain, Bosnia and Herzegovina, Italy, and Portugal. We present here the analysis of uncharacterized nematodes obtained from gastric nodules of...
journal_title:Parasitology research
pub_type: 杂志文章
doi:10.1007/s00436-020-06791-4
更新日期:2020-09-01 00:00:00
abstract::Water buffalo is important livestock in several countries in the Latin American and Caribbean regions. This buffalo species can be infected by tick-borne hemoparasites and remains a carrier of these pathogens which represent a risk of infection for more susceptible species like cattle. Therefore, studies on the epidem...
journal_title:Parasitology research
pub_type: 杂志文章
doi:10.1007/s00436-018-06194-6
更新日期:2019-03-01 00:00:00
abstract::The time-course of the detection of circulating and urinary filarial antigens was followed with a 2S-IRMA assay, using a mouse monoclonal antibody raised against Brugia malayi larvae, in Mastomys natalensis experimentally infected with Brugia malayi, Brugia pahangi, or Litomosoides carinii. In the prepatent phase of t...
journal_title:Parasitology research
pub_type: 杂志文章
doi:10.1007/BF00536033
更新日期:1987-01-01 00:00:00
abstract::DNA plasmid immunization is a novel approach of preventive and therapeutic vaccine. More than 100 DNA vaccines have been on preclinical or clinical phase trials, and four kinds of DNA vaccines for livestock have been approved by USDA, CFIA, and APVMA. Schistosomiasis is a worldwide parasitic disease, and vaccine immun...
journal_title:Parasitology research
pub_type: 杂志文章
doi:10.1007/s00436-012-3104-6
更新日期:2013-01-01 00:00:00
abstract::Antibody responses to naturally acquired Plasmodium relictum and P. elongatum infections, blood parasitemia, and disease signs were investigated in 23 naive juvenile African black-footed penguins (Spheniscus demersus). Anti-Plasmodium spp. immunoglobulins were detected by enzyme-linked immunosorbent assay (ELISA) usin...
journal_title:Parasitology research
pub_type: 杂志文章
doi:10.1007/BF00932944
更新日期:1994-01-01 00:00:00
abstract::A LightCycler real-time polymerase chain reaction (PCR) assay was developed to detect Wuchereria bancrofti DNA in blood-fed mosquitoes. The assay is based on fluorescence melting curve analysis of the PCR product generated from a family of repeated DNA elements: the 182 bp SspI repeat, specific to the genus Wuchereria...
journal_title:Parasitology research
pub_type: 杂志文章
doi:10.1007/s00436-004-1221-6
更新日期:2004-11-01 00:00:00
abstract::Twenty-four Holando Argentino male calves were treated orally with 50 mg/kg body weight trichlorphon (TCF); 0.2 mg/kg body weight subcutaneous ivermectin (IVM); a combination of TCF+IVM at the same doses and administration routes; or remained untreated (control group). All calves were necropsied at day 14 post treatme...
journal_title:Parasitology research
pub_type: 杂志文章
doi:10.1007/s00436-011-2407-3
更新日期:2011-08-01 00:00:00
abstract::Exsheathment and midgut invasion of nocturnally subperiodic Brugia malayi microfilariae were analyzed using light and scanning electron microscopy in a refractory vector, Aedes aegypti (Thailand strain). Results showed that exsheathed microfilariae represented only approximately 1% of the total microfilaria midguts di...
journal_title:Parasitology research
pub_type: 杂志文章
doi:10.1007/s00436-014-4086-3
更新日期:2014-11-01 00:00:00
abstract::Specific anti-newborn larva antibodies present in the serum of rats chronically infected with Trichinella spiralis were incapable of inducing killing of newborn larvae by activation of normal peritoneal cells. These late antibodies blocked the cytotoxic reaction induced by early antibodies produced a few weeks after i...
journal_title:Parasitology research
pub_type: 杂志文章
doi:10.1007/s004360050072
更新日期:1996-01-01 00:00:00
abstract::Cystic echinococcosis is a worldwide zoonosis caused by Echinococcus granulosus. Because the methods of diagnosis and treatment for cystic echinococcosis were limited, it is still necessary to screen target proteins for the development of new anti-hydatidosis vaccine. In this study, the triosephosphate isomerase gene ...
journal_title:Parasitology research
pub_type: 杂志文章
doi:10.1007/s00436-016-5166-3
更新日期:2016-10-01 00:00:00
abstract::Murine immunological responses to experimental infection with Trichuris muris and the effects of the resident microbiota on these responses are of increasing interest. For these studies, accurate dose delivery and improved sterilization of inocula are essential to prevent co-infection with unknown contaminants. We fou...
journal_title:Parasitology research
pub_type: 杂志文章
doi:10.1007/s00436-010-1978-8
更新日期:2010-10-01 00:00:00