Abstract：
:Excystation of Giardia lamblia entails differentiation of dormant cysts into parasitic trophozoites. Despite its importance for infection, this transformation is not understood at the cellular or molecular levels. In these studies, we report that excystation entails detection of environmental stimuli across the tough extracellular cyst wall leading to highly coordinated physiological, structural, and molecular responses. We found that novel cytoplasmic rearrangements and changes in individual species of mRNA and in cytoplasmic pH occur within the cyst wall in the earliest stage of excystation, in response to conditions modeling cyst ingestion and passage into the human stomach. This suggests that cysts do not contain all the mRNA needed for excystation and emergence and supports our hypothesis that external stimuli, including hydrogen ions, may penetrate or be perceived across the cyst wall. In contrast, changes in cyst wall structure or proteins were detected only later in excystation, in the stage that models passage into the human small intestine, where trophozoites can emerge and survive. These findings show that excystation of G. lamblia is a highly complex and active process and provide important insights into its cellular and molecular components.
journal_name
Exp Parasitoljournal_title
Experimental parasitologyauthors
Hetsko ML,McCaffery JM,Svärd SG,Meng TC,Que X,Gillin FDdoi
10.1006/expr.1998.4246subject
Has Abstractpub_date
1998-03-01 00:00:00pages
172-83issue
3eissn
0014-4894issn
1090-2449pii
S0014-4894(98)94246-1journal_volume
88pub_type
杂志文章abstract：:Considering that the treatment for toxoplasmosis is based on drugs that show limited efficacy due to their substantial side effects, the purpose of the present study was to evaluate the effects of Artemisia annua on in vitro and in vivo Toxoplasma gondii infection. A. annua infusion was prepared from dried herb and te...
journal_title：Experimental parasitology
pub_type： 杂志文章
doi：10.1016/j.exppara.2009.04.010
更新日期：2009-07-01 00:00:00
abstract：:The reactivity to overlapping decapeptides based on sequences of human band 3 protein was determined for 24 rabbit serum samples. A high percentage of the sera recognized sequences of amino acid 650-670, as well as several other sequences representing putative exofacial regions of the band 3 protein. When sera were us...
journal_title：Experimental parasitology
pub_type： 杂志文章
doi：10.1006/expr.1996.0006
更新日期：1996-01-01 00:00:00
abstract：:Homogenates of Giardia lamblia trophozoites exhibited the following hydrolase activities: acid phosphatase (EC 3.1.3.2), proteinase (EC 3.1.4) with urea-denatured hemoglobin and N-benzoyl-DL-arginine-2-naphthylamide as substrates, deoxyribonuclease (EC 3.1.4.5), and ribonuclease (EC 2.7.7.16). beta-N-Acetylglucosamini...
journal_title：Experimental parasitology
pub_type： 杂志文章
doi：10.1016/0014-4894(88)90116-6
更新日期：1988-02-01 00:00:00
abstract：:This article has been withdrawn at the request of the author(s) and/or editor. The Publisher apologizes for any inconvenience this may cause. The full Elsevier Policy on Article Withdrawal can be found at http://www.elsevier.com/locate/withdrawalpolicy. ...
journal_title：Experimental parasitology
pub_type： 杂志文章
doi：10.1016/j.exppara.2012.04.001
更新日期：2012-04-11 00:00:00
abstract：:Amoebae of the genus Acanthamoeba are free-living protozoa that can cause granulomatous encephalitis and keratitis in humans. In this study, four clinical and three household dust isolates obtained in Vitória, Espírito Santo, Brazil were characterized by their morphological, genotypic, and physiological properties. Al...
journal_title：Experimental parasitology
pub_type： 杂志文章
doi：10.1016/j.exppara.2013.05.013
更新日期：2013-09-01 00:00:00
abstract：:Rosetting is a parasite adhesion phenotype associated with severe malaria in African children. Why parasites form rosettes is unknown, although enhanced invasion or immune evasion have been suggested as possible functions. Previous work showed that rosetting does not enhance parasite invasion under standard in vitro c...
journal_title：Experimental parasitology
pub_type： 杂志文章
doi：10.1016/j.exppara.2005.11.007
更新日期：2006-04-01 00:00:00
abstract：:In this work CD4-knockout mice were used as a model to analyse the role of CD4+ T cells in the antibody response against Echinococcus granulosus immunization or experimental infection. Results obtained with mice immunized with protoscolex antigens indicated that these contain T-independent antigens. After infection, C...
journal_title：Experimental parasitology
pub_type： 杂志文章
doi：10.1016/j.exppara.2008.04.024
更新日期：2008-08-01 00:00:00
abstract：:There is evidence which suggests that malaria sporozoites recognize mosquito salivary glands by specific receptor-ligand interactions. We are interested in identifying the putative salivary gland receptor(s) for sporozoite invasion. We used an in vivo bioassay for sporozoite invasion of salivary glands. In this assay,...
journal_title：Experimental parasitology
pub_type： 杂志文章
doi：10.1006/expr.1995.1124
更新日期：1995-11-01 00:00:00
abstract：:Phospholipid metabolism of the microsporidian Encephalitozoon cuniculi, an obligate intracellular parasite, has been investigated. Labeled precursor incorporation experiments have shown that phosphatidylserine decarboxylase and phosphatidylethanolamine N-methyltransferase are more active in cells infected by E. cunicu...
journal_title：Experimental parasitology
pub_type： 杂志文章
doi：10.1006/expr.2001.4635
更新日期：2001-08-01 00:00:00
abstract：:In the present study, the gene expression of three multidrug resistance (MDR) and resistance-associated protein (MRP) transport proteins or efflux pumps was characterized and the phenotypic evidence for such pumps was demonstrated in cultured Madin-Darby canine kidney (MDCK) cells. A gradient for the fluorescent probe...
journal_title：Experimental parasitology
pub_type： 杂志文章
doi：10.1016/j.exppara.2004.03.012
更新日期：2004-03-01 00:00:00
abstract：:A cDNA encoding elastase was isolated from Steinernema carpocapsae by suppression subtractive hybridization and rapid amplification of 5' cDNA ends. The predicted protein contained a 19-aa signal peptide, a 44-aa N-terminal propeptide, and a 264-aa mature protein with a predicted molecular mass of 28,949 Da and a theo...
journal_title：Experimental parasitology
pub_type： 杂志文章
doi：10.1016/j.exppara.2009.01.014
更新日期：2009-05-01 00:00:00
abstract：:Giardia lamblia, an early diverging eukaryote that infects several species including humans and a major agent of water-borne diarrhea throughout the world, can be infected with a double-stranded RNA virus, giardiavirus (GLV). A chimeric GLV cDNA and green fluorescent protein (GFP) according to the cis-acting signals o...
journal_title：Experimental parasitology
pub_type： 杂志文章
doi：10.1016/j.exppara.2004.12.006
更新日期：2005-03-01 00:00:00
abstract：:The in vitro growth of Plasmodium falciparum was reduced by 35 and 43% through high concentrations (5 mmole/liter) of magnesium in RPMI medium and magnesium-free medium, respectively, after 48 hr, whereas no significant inhibition could be observed under these conditions after 24 hr cultivation in the respective mediu...
journal_title：Experimental parasitology
pub_type： 杂志文章
doi：10.1006/expr.1995.1023
更新日期：1995-03-01 00:00:00
abstract：:A monoclonal antibody specific for the Theileria parva sporozoite, which recognizes a determinant on the surface coat and blocks sporozoite infectivity, was used to investigate the presence of the determinant on other stages of the parasite lifecycle. Immunofluorescence techniques did not demonstrate this determinant ...
journal_title：Experimental parasitology
pub_type： 杂志文章
doi：10.1016/s0014-4894(85)80026-6
更新日期：1985-08-01 00:00:00
abstract：:The infection with blood stages of Plasmodium chabaudi chabaudi (AS) was followed in BALB/c and DBA/2 mice. Both strains show a peak parasitemia by 7-9 days after infection, display splenic hypercellularity of T and B cells, thymic atrophy, nearly complete depletion of B cells in the bone marrow, and mount comparable ...
journal_title：Experimental parasitology
pub_type： 杂志文章
doi：10.1016/j.exppara.2005.03.024
更新日期：2005-08-01 00:00:00
abstract：:Coccidiosis is a major parasitic disease of poultry industry and an ideal vaccine should induce long-lasting cross-species protective immunity. Broiler chickens (Cobb 500) were inoculated with single, double or triple injections of a synthetic peptide (derived from sequences of Eimeria acervulina and Eimeria tenella a...
journal_title：Experimental parasitology
pub_type： 杂志文章
doi：10.1016/j.exppara.2005.03.026
更新日期：2005-08-01 00:00:00
abstract：:Many methods have been proposed for removing contaminating host cells from mouse peritoneal exudates infected with Toxoplasma gondii tachyzoites. Of these, eight established methods were compared. They were density gradients, sonication and trypsin digestion, differential centrifugation, haemolysin digestion, filtrati...
journal_title：Experimental parasitology
pub_type： 杂志文章
doi：10.1016/0014-4894(84)90080-8
更新日期：1984-04-01 00:00:00
abstract：:The analysis of PvuII restriction patterns of Leishmania spp. and Trypanosoma spp. genomic DNA showed genus distinctive profiles. A specific PvuII site was detected in the 5' domain of 18S ribosomal DNA of Leishmania. A 20-mer oligonucleotide encompassing this PvuII region was synthesized. This sequence, when utilized...
journal_title：Experimental parasitology
pub_type： 杂志文章
doi：10.1016/0014-4894(91)90133-h
更新日期：1991-02-01 00:00:00
abstract：:The experiments described here report on the correlation between the ex vivo diffusion of different benzimidazole (BZD) anthelmintics into the cestode parasite Moniezia benedeni, and their octanol-water partition coefficients (P.C.). The characterisation of the drug diffusion process into target parasites is relevant ...
journal_title：Experimental parasitology
pub_type： 杂志文章
doi：10.1016/s0014-4894(03)00060-2
更新日期：2003-01-01 00:00:00
abstract：:Two different diets for the host and three drug dosage regimens were used to select lines resistant to sulfadoxine and pyrimethamine from the parent strain of the rodent malaria parasite Plasmodium berghei [the N (K173) strain]. A higher yield of resistance was obtained when a high parasitemia was present at the begin...
journal_title：Experimental parasitology
pub_type： 杂志文章
doi：10.1016/0014-4894(83)90034-6
更新日期：1983-06-01 00:00:00
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journal_title：Experimental parasitology
pub_type： 杂志文章
doi：10.1016/j.exppara.2015.06.001
更新日期：2015-09-01 00:00:00
abstract：:The cDNA clone coding a major vault protein (MVP)-like protein was derived from Echinococcus multilocularis cysts. MVP is a main component of vault particles, which are the largest cytoplasmic ribonucleoprotein particles in eukaryotic cells. We sequenced and characterized E. multilocularis MVP (EmMVP). The nucleotide ...
journal_title：Experimental parasitology
pub_type： 杂志文章
doi：10.1016/j.exppara.2013.02.015
更新日期：2013-05-01 00:00:00
abstract：:Giardia lamblia undergo surface antigenic variation in vitro and in vivo. The presence of variant trophozoites can be detected in clones after exposure to cytotoxic monoclonal antibodies. Surviving Giardia (progeny) no longer possess the initial major surface antigen which is replaced by new antigens. Exposure of a cl...
journal_title：Experimental parasitology
pub_type： 杂志文章,评审
doi：10.1016/0014-4894(89)90104-5
更新日期：1989-02-01 00:00:00
abstract：:Non-invasive small animal in vivo imaging is an essential tool in a broad variety of biomedical sciences and enables continuous monitoring of disease progression in order to develop and improve diagnostic, therapeutic and preventive measures. Imaging parasites non-invasively in live animals allows efficient parasite d...
journal_title：Experimental parasitology
pub_type： 杂志文章
doi：10.1016/j.exppara.2020.107905
更新日期：2020-07-01 00:00:00
abstract：:Schistosomiasis remains a global health problem. In the Mekong river basin, approximately 80,000 people are at risk of infection by Schistosoma mekongi. The parasite's eggs become entrapped in the host's organs and induce massive inflammation, contributing to the pathogenesis of schistosomiasis. In addition, egg antig...
journal_title：Experimental parasitology
pub_type： 杂志文章
doi：10.1016/j.exppara.2018.07.002
更新日期：2018-08-01 00:00:00
abstract：:Infectivity of the multicellular pathogen Schistosoma mansoni for the human host is dependent upon the ability of free-living cercariae to transform rapidly into parasitic schistosomula. The biochemical pathways that regulate this transitional period are unknown. The role of protein phosphorylation was investigated by...
journal_title：Experimental parasitology
pub_type： 杂志文章
doi：10.1016/0014-4894(91)90024-q
更新日期：1991-08-01 00:00:00
abstract：:Neospora caninum causes abortion in cattle and neurological disorders in dogs. The immunological response to this parasite has been described as predominantly of the Th1 type. However, infected primary glial cell cultures release IL-10 and IL-6 but not IFN-γ. This suggests a rather protective response of the glia to a...
journal_title：Experimental parasitology
pub_type： 杂志文章
doi：10.1016/j.exppara.2012.11.016
更新日期：2013-03-01 00:00:00
abstract：:Hepatocytic metaplasia may be induced in hamsters by carcinogens, and associated with aging, diabetes or chronic pancreatitis. By means of histopathologic and immunohistochemic studies, we observed pancreatic hepatocytes in hamsters infected and reinfected with Trypanosoma cruzi. The change was seen in 18 (19%) out of...
journal_title：Experimental parasitology
pub_type： 杂志文章
doi：10.1016/S0014-4894(02)00005-X
更新日期：2002-02-01 00:00:00
abstract：:We report here the pre-mRNA 3' end processing machinery in Entamoeba histolytica. Comparative analysis of the putative sequences participating in the pre-mRNA 3' end processing of E. histolytica genes shows similitude and differences to those described for yeast and human transcripts. By a genomic survey, we identifie...
journal_title：Experimental parasitology
pub_type： 杂志文章
doi：10.1016/j.exppara.2005.02.024
更新日期：2005-07-01 00:00:00
abstract：:The oxidative metabolism of peritoneal macrophages (PM) and neutrophils from nifedipine (calcium channel blocker)-treated, Plasmodium berghei (NK 65)-infected and normal infected Swiss Albino mice was studied. A significant fall in oxidative metabolism as evidenced by decreased chemiluminescence (CL) response (P less ...
journal_title：Experimental parasitology
pub_type： 杂志文章
doi：10.1016/0014-4894(92)90135-w
更新日期：1992-02-01 00:00:00
