The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform
Nelson Lima - One of the best experts on this subject based on the ideXlab platform.
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morphological and physiological changes in tetrahymena pyriformis for the in vitro cytotoXicity assessment of Triton X 100
Toxicology in Vitro, 2003Co-Authors: Nicolina Dias, Renato A Mortara, Nelson LimaAbstract:Non-ionic surfactants such as Triton X-100 have been widely used in industrial processing and in cleaning products for almost 50 years, being effective and economic emulsifying, wetting agents, dispersants and solubilizers. Cleaning products containing these surfactants are disposed of mainly by discharge into wastewater, which receives biological treatment in wastewater treatment systems. However, surface-active agents interact with eukaryotic cell membranes leading to biological damage at high concentrations. Tetrahymena pyriformis was used here as model organism to assess the effects of Triton X-100 through a series of in vitro cytotoXicity tests. Growth rates and morphological changes were, by their simplicity and reproducibility, the simplest toXicological assays. Cytoskeleton analysis seemed to be related with phagocytosis rate. Viability was evaluated by two different tests. Calcein AM/EthD-1 was used to assess T. pyriformis membrane damage during the 48-h eXperiment. The colorimetric MTT assay proved to be highly sensitive even at very short periods of Triton X-100 eXposure. Tests performed in this study included simple and fast bioassays that provide overall information on the morphological and physiological state of cells eXposed to different non-lytic and lytic concentrations of Triton X-100.
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physiological responses of tetrahymena pyriformis to copper zinc cycloheXimide and Triton X 100
FEMS Microbiology Ecology, 1999Co-Authors: Ana Nicolau, M Mota, Nelson LimaAbstract:Protozoa, and particularly ciliates, are essential in aerobic purification processes of wastewaters and have proved to be very sensitive to environmental changes. The physiological response of the ciliate Tetrahymena pyriformis was assessed in terms of mortality, growth and grazing capacity after eXposure to four toXicants: copper, zinc, cycloheXimide and Triton X-100. In the ranges of concentrations used, mortality, inhibition of growth and inhibition of grazing were observed with all toXicants employed, but in different ways. Copper and zinc showed lower toXicity than observed in other studies with protozoa, though some of the present results are in accordance with those reported by other authors. This supports the importance of the organism tested and the eXperimental conditions of the bioassays.
Maarit Suomalainen - One of the best experts on this subject based on the ideXlab platform.
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human immunodeficiency virus type 1 assembly and lipid rafts pr55gag associates with membrane domains that are largely resistant to brij98 but sensitive to Triton X 100
Journal of Virology, 2003Co-Authors: Kirsi Holm, Katarzyna Weclewicz, Roger Hewson, Maarit SuomalainenAbstract:The assembly and budding of human immunodeficiency virus type 1 (HIV-1) at the plasma membrane are directed by the viral core protein Pr55gag. We have analyzed whether Pr55gag has intrinsic affinity for sphingolipid- and cholesterol-enriched raft microdomains at the plasma membrane. Pr55gag has previously been reported to associate with Triton X-100-resistant rafts, since both intracellular membranes and virus-like Pr55gag particles (VLPs) yield buoyant Pr55gag compleXes upon Triton X-100 eXtraction at cold temperatures, a phenotype that is usually considered to indicate association of a protein with rafts. However, we show here that the buoyant density of Triton X-100-treated Pr55gag compleXes cannot be taken as a proof for raft association of Pr55gag, since lipid analyses of Triton X-100-treated VLPs demonstrated that the detergent readily solubilizes the bulk of membrane lipids from Pr55gag. However, Pr55gag might nevertheless be a raft-associated protein, since confocal fluorescence microscopy indicated that coalescence of GM1-positive rafts at the cell surface led to copatching of membrane-bound Pr55gag. Furthermore, eXtraction of intracellular membranes or VLPs with Brij98 yielded buoyant Pr55gag compleXes of low density. Lipid analyses of Brij98-treated VLPs suggested that a large fraction of the envelope cholesterol and phospholipids was resistant to Brij98. Collectively, these results suggest that Pr55gag localizes to membrane microdomains that are largely resistant to Brij98 but sensitive to Triton X-100, and these membrane domains provide the platform for assembly and budding of Pr55gag VLPs.
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human immunodeficiency virus type 1 assembly and lipid rafts pr55 gag associates with membrane domains that are largely resistant to brij98 but sensitive to Triton X 100
Journal of Virology, 2003Co-Authors: Kirsi Holm, Katarzyna Weclewicz, Roger Hewson, Maarit SuomalainenAbstract:The assembly and budding of human immunodeficiency virus type 1 (HIV-1) at the plasma membrane are directed by the viral core protein Pr55gag. We have analyzed whether Pr55gag has intrinsic affinity for sphingolipid- and cholesterol-enriched raft microdomains at the plasma membrane. Pr55gag has previously been reported to associate with Triton X-100-resistant rafts, since both intracellular membranes and virus-like Pr55gag particles (VLPs) yield buoyant Pr55gag compleXes upon Triton X-100 eXtraction at cold temperatures, a phenotype that is usually considered to indicate association of a protein with rafts. However, we show here that the buoyant density of Triton X-100-treated Pr55gag compleXes cannot be taken as a proof for raft association of Pr55gag, since lipid analyses of Triton X-100-treated VLPs demonstrated that the detergent readily solubilizes the bulk of membrane lipids from Pr55gag. However, Pr55gag might nevertheless be a raft-associated protein, since confocal fluorescence microscopy indicated that coalescence of GM1-positive rafts at the cell surface led to copatching of membrane-bound Pr55gag. Furthermore, eXtraction of intracellular membranes or VLPs with Brij98 yielded buoyant Pr55gag compleXes of low density. Lipid analyses of Brij98-treated VLPs suggested that a large fraction of the envelope cholesterol and phospholipids was resistant to Brij98. Collectively, these results suggest that Pr55gag localizes to membrane microdomains that are largely resistant to Brij98 but sensitive to Triton X-100, and these membrane domains provide the platform for assembly and budding of Pr55gag VLPs.
Masahito Yamazaki - One of the best experts on this subject based on the ideXlab platform.
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stability of giant unilamellar vesicles and large unilamellar vesicles of liquid ordered phase membranes in the presence of Triton X 100
Biochimica et Biophysica Acta, 2004Co-Authors: Yukihiro Tamba, Takeshi Yahagi, Tomoki Tanaka, Yuko Yamashita, Masahito YamazakiAbstract:We have investigated the stability of giant unilamellar vesicles (GUVs) and large unilamellar vesicles (LUVs) of lipid membranes in the liquid-ordered phase (lo phase) against a detergent, Triton X-100. We found that in the presence of high concentrations of Triton X-100, the structure of GUVs and LUVs of dipalmitoyl-PC (DPPC)/cholesterol (chol) and sphingomyelin (SM)/chol membranes in the lo phase was stable and no leakage of fluorescent probes from the vesicles occurred. We also found that ether-linked diheXadecylphosphatidylcholine (DHPC) membranes containing more than 20 mol% cholesterol were in the lo phase, and that DHPC/chol-GUV and DHPC/chol-LUV in the lo phase were stable and no leakage of internal contents occurred in the presence of Triton X-100. In contrast, octylglucoside solution could easily break these GUVs and LUVs of the lo phase membranes and induced internal contents leakage. These data indicate that GUVs and LUVs of the lo phase membranes are very valuable for practical use.
Maria Grazia Paglia - One of the best experts on this subject based on the ideXlab platform.
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evaluation of the inactivation effect of Triton X 100 on ebola virus infectivity
Journal of Clinical Virology, 2017Co-Authors: Francesca Colavita, Serena Quartu, Eleonora Lalle, L Bordi, Daniele Lapa, Silvia Meschi, Antonella Vulcano, Antonietta Toffoletti, Eugenio Bordi, Maria Grazia PagliaAbstract:Abstract Background The recent Ebola virus disease outbreak occurred in West Africa since December 2013 highlighted the need of appropriate virus inactivation procedures to be set up to allow the necessary processing of specimens outside BSL-4 facilities and to perform laboratory tests without affecting clinical decisions. For this purpose, international guidelines suggest the pre-treatment of the samples with Triton X-100. Objectives Due to the limited scientific evidence about the efficacy of Triton X-100 on enveloped-viruses, the aim of this work was to evaluate the effect of Triton X-100 on the virus infectivity and to establish the optimal conditions for its use. Study design We evaluated the effect of Triton X-100 on the infectivity of enveloped-viruses such as West Nile virus (WNV) and Ebola virus (EBOV) at different eXperimental conditions. The residual virus infectivity was measured by limiting dilution assay on Vero E6 cells. Repeated eXperiments were performed, as specified, and for the titration of residual infectivity each dilution was tested in triplicate. Results Results obtained with WNV showed that infectivity was reduced by 6 Logs, after 1 h of treatment with different concentrations of Triton X-100 (ranging from 0.5% to 0.05%). This effect was not time-dependent using 0.1% Triton X-100. Subsequently, we applied the method on EBOV and one hour eXposure to 0.1% Triton X-100 strongly affected EBOV infectivity (4 Logs of infectivity reduction). Conclusions We report that Triton X-100, when used alone, is able to strongly reduce the infectivity of a classical enveloped virus such as WNV and we provide, for the first time, scientific evidence that 0.1% Triton X-100 efficaciously affect Ebola virus infectivity. Even though a complete virus inactivation is not achieved, Triton X-100 certainly can contribute to mitigate the risk for the workers of accidental infection and improve the overall safety of the laboratory procedures. Further studies must be performed to deeply investigate alternative solutions able to balance higher level of safety and good performance in clinical chemistry and hematology parameters analysis, necessary for the appropriate and effective management of EVD patients.
Kirsi Holm - One of the best experts on this subject based on the ideXlab platform.
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human immunodeficiency virus type 1 assembly and lipid rafts pr55gag associates with membrane domains that are largely resistant to brij98 but sensitive to Triton X 100
Journal of Virology, 2003Co-Authors: Kirsi Holm, Katarzyna Weclewicz, Roger Hewson, Maarit SuomalainenAbstract:The assembly and budding of human immunodeficiency virus type 1 (HIV-1) at the plasma membrane are directed by the viral core protein Pr55gag. We have analyzed whether Pr55gag has intrinsic affinity for sphingolipid- and cholesterol-enriched raft microdomains at the plasma membrane. Pr55gag has previously been reported to associate with Triton X-100-resistant rafts, since both intracellular membranes and virus-like Pr55gag particles (VLPs) yield buoyant Pr55gag compleXes upon Triton X-100 eXtraction at cold temperatures, a phenotype that is usually considered to indicate association of a protein with rafts. However, we show here that the buoyant density of Triton X-100-treated Pr55gag compleXes cannot be taken as a proof for raft association of Pr55gag, since lipid analyses of Triton X-100-treated VLPs demonstrated that the detergent readily solubilizes the bulk of membrane lipids from Pr55gag. However, Pr55gag might nevertheless be a raft-associated protein, since confocal fluorescence microscopy indicated that coalescence of GM1-positive rafts at the cell surface led to copatching of membrane-bound Pr55gag. Furthermore, eXtraction of intracellular membranes or VLPs with Brij98 yielded buoyant Pr55gag compleXes of low density. Lipid analyses of Brij98-treated VLPs suggested that a large fraction of the envelope cholesterol and phospholipids was resistant to Brij98. Collectively, these results suggest that Pr55gag localizes to membrane microdomains that are largely resistant to Brij98 but sensitive to Triton X-100, and these membrane domains provide the platform for assembly and budding of Pr55gag VLPs.
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human immunodeficiency virus type 1 assembly and lipid rafts pr55 gag associates with membrane domains that are largely resistant to brij98 but sensitive to Triton X 100
Journal of Virology, 2003Co-Authors: Kirsi Holm, Katarzyna Weclewicz, Roger Hewson, Maarit SuomalainenAbstract:The assembly and budding of human immunodeficiency virus type 1 (HIV-1) at the plasma membrane are directed by the viral core protein Pr55gag. We have analyzed whether Pr55gag has intrinsic affinity for sphingolipid- and cholesterol-enriched raft microdomains at the plasma membrane. Pr55gag has previously been reported to associate with Triton X-100-resistant rafts, since both intracellular membranes and virus-like Pr55gag particles (VLPs) yield buoyant Pr55gag compleXes upon Triton X-100 eXtraction at cold temperatures, a phenotype that is usually considered to indicate association of a protein with rafts. However, we show here that the buoyant density of Triton X-100-treated Pr55gag compleXes cannot be taken as a proof for raft association of Pr55gag, since lipid analyses of Triton X-100-treated VLPs demonstrated that the detergent readily solubilizes the bulk of membrane lipids from Pr55gag. However, Pr55gag might nevertheless be a raft-associated protein, since confocal fluorescence microscopy indicated that coalescence of GM1-positive rafts at the cell surface led to copatching of membrane-bound Pr55gag. Furthermore, eXtraction of intracellular membranes or VLPs with Brij98 yielded buoyant Pr55gag compleXes of low density. Lipid analyses of Brij98-treated VLPs suggested that a large fraction of the envelope cholesterol and phospholipids was resistant to Brij98. Collectively, these results suggest that Pr55gag localizes to membrane microdomains that are largely resistant to Brij98 but sensitive to Triton X-100, and these membrane domains provide the platform for assembly and budding of Pr55gag VLPs.
