scholarly journals Toxic Effects of Ag(I) and Hg(II) on Candida albicans and C. maltosa: a Flow Cytometric Evaluation

2001 ◽  
Vol 67 (9) ◽  
pp. 4030-4035 ◽  
Author(s):  
Shangtong Zhang ◽  
Sidney A. Crow
Keyword(s):  
Candida Albicans ◽  
Membrane Potential ◽  
Propidium Iodide ◽  
Membrane Integrity ◽  
Membrane Potentials ◽  
Membrane Permeabilization ◽  
Toxic Effects ◽  
Flow Cytometric ◽  
Cell Depolarization ◽  
Flow Cytometric Evaluation

ABSTRACT The effects of Ag(I) and Hg(II) on membrane potential and integrity of cells of Candida albicans and C. maltosa were determined with a flow cytometric procedure that employed an anionic membrane potential-sensitive dye, bis-(1,3-dibutylbarbituric acid) trimethine oxonol, and a membrane integrity indicator, propidium iodide. The membrane potentials of cells of both species were reduced rapidly within 15 min of exposure to Ag(I). No threshold dose for Hg(II) existed, and cells of both species lost membrane potential gradually in Hg(II) solutions. Cells of both species lost membrane integrity more rapidly in Ag(I) solutions than in Hg(II) solutions. In Ag(I) solutions, the decrease in the numbers of cells recoverable in culture occurred at a rate similar to the rate of cell depolarization and membrane permeabilization. In Hg(II) solutions, loss of cell recoverability preceded the loss of membrane potential and membrane integrity. C. albicans, in contrast toC. maltosa, showed no loss of membrane integrity after exposure to Hg(II) solutions for 1 h. Different rates of binding of Ag(I) and Hg(II) between the two species suggest that the two ions target different primary sites.

scholarly journals Flow cytometric evaluation of DNA stainability with propidium iodide after histone H1 extraction

Cytometry ◽  
1989 ◽  
Vol 10 (6) ◽  
pp. 726-730 ◽  
Author(s):  
Maria Chiara Giangarè ◽  
Ennio Prosperi ◽  
Guido Pedrali-Noy ◽  
Giovanni Bottiroli
Keyword(s):  
Propidium Iodide ◽  
Histone H1 ◽  
Flow Cytometric ◽  
Flow Cytometric Evaluation

Membrane Transport in Anoxic Rice Coleoptiles and Storage Tissues of Beetroot

1995 ◽  
Vol 22 (6) ◽  
pp. 965 ◽  
Author(s):  
Qisen Zhang ◽  
H Greenway
Keyword(s):  
Membrane Potential ◽  
Ion Transport ◽  
Membrane Transport ◽  
Membrane Integrity ◽  
Atp Synthesis ◽  
Membrane Potentials ◽  
Membrane Properties ◽  
Alcohol Fermentation ◽  
Electrogenic Ion Transport ◽  
And Storage

Rice coleoptiles and aged storage tissues of beetroot are both tolerant to anoxia. Both types of tissues retain their membrane integrity over several days of anoxia and take up glucose and sucrose from 0.5 mol m-3 external concentrations at 40-65% of the rate of the aerated tissues. However, these tissues show substantial differences in other membrane properties under anoxia. Anoxic rice coleoptiles had membrane potentials generated by electrogenic ion transport, i.e. these tissues retained, at least partially, their ATP-dependent H+ extrusion. This conclusion is based on the following evidence: (1) The membrane potentials under aeration were between -120 and -130 mV and these depolarised to between -75 and -98 mV immediately upon exposure to anoxia, but repolarised to between -109 and -122 mV after 1 h. (2) Addition of carboxy-cyanide m-chlorophenylhydrazone (CCCP) and iodoacetamide during anoxia depolarised the membranes from -120 mV to -68 and -86 mV, respectively. (3) Transient membrane depolarisations following addition of sugars and amino acids, ranging between 10 and 35 mV, were similar during anoxia and aeration. In contrast to the rice coleoptiles, cell membranes of anoxic storage tissues of beetroot were, at most, weakly energised since they depolarised from between -156 and -159 mV in aerated tissues to -97 mV upon transfer to anoxia and this membrane potential was retained for at least 72 h of anoxia (longest time measured). Another difference between the two types of tissues was for Cl- uptake from 0.25 mol m-3 external Cl-. The anoxic rice coleoptiles took up Cl- at 10-15% of the rates during aeration, while there was no detectable Cl- uptake by the anoxic storage tissues of beetroot. The persistence of membrane potentials generated by electrogenic ion transport in anoxic rice coleoptiles, but not in anoxic storage tissues of beetroot, may be associated with higher rates of alcohol fermentation, and therefore of glycolysis and ATP synthesis, in the rice coleoptiles than in the storage tissues of beetroot. Extra keywords: rice coleoptiles, beetroot, anoxia, membrane transport, membrane potential.

scholarly journals Flow cytometric quantitation of phagocytosis in heparinized complete blood with latex particles and Candida albicans

1997 ◽  
Vol 30 (6) ◽  
pp. 441-446 ◽  
Author(s):  
Jesús M. Egido ◽  
Juan Viñuelas
Keyword(s):  
Candida Albicans ◽  
Rapid Method ◽  
Propidium Iodide ◽  
Standard Technique ◽  
Intracellular Killing ◽  
Latex Particles ◽  
Flow Cytometric

We report a rapid method for the flow cytometric quantitation of phagocytosis in heparinized complete peripherial blood (HCPB), using commercially available phycoerythrin-conjugated latex particles of 1µm diameter. The method is faster and shows greater reproducibility than Bjerknes' (1984) standard technique using propidium iodide-stained Candida albicans, conventionally applied to the leukocytic layer of peripherial blood but here modified for HCPB. We also report a modification of Bjerknes' Intracellular Killing Test to allow its application to HCPB.

Flow Cytometric Evaluation of the Ongoing Angiogenic Response in Rat Cardiac Tissue Following Myocardial Infarction

2021 ◽  
Vol 1 (2) ◽  
Author(s):  
Cecilie Hoeeg ◽  
Lars Ringgaard ◽  
Esben Christensen ◽  
Bjarke Follin ◽  
Simon Bentsen ◽  
...  
Keyword(s):  
Myocardial Infarction ◽  
Cardiac Tissue ◽  
Angiogenic Response ◽  
Flow Cytometric ◽  
Flow Cytometric Evaluation

scholarly journals On the Wireless Microwave Sensing of Bacterial Membrane Potential in Microfluidic-Actuated Platforms

Sensors ◽  
2021 ◽  
Vol 21 (10) ◽  
pp. 3420
Author(s):  
Marc Jofre ◽  
Lluís Jofre ◽  
Luis Jofre-Roca
Keyword(s):  
Membrane Potential ◽  
Living Cells ◽  
Membrane Potentials ◽  
Electromagnetic Properties ◽  
Bacterial Membrane ◽  
Microfluidic Platforms ◽  
Bacterial Membranes ◽  
Wireless Monitoring ◽  
Bacterial Dynamics ◽  
Engineered Systems

The investigation of the electromagnetic properties of biological particles in microfluidic platforms may enable microwave wireless monitoring and interaction with the functional activity of microorganisms. Of high relevance are the action and membrane potentials as they are some of the most important parameters of living cells. In particular, the complex mechanisms of a cell’s action potential are comparable to the dynamics of bacterial membranes, and consequently focusing on the latter provides a simplified framework for advancing the current techniques and knowledge of general bacterial dynamics. In this work, we provide a theoretical analysis and experimental results on the microwave detection of microorganisms within a microfluidic-based platform for sensing the membrane potential of bacteria. The results further advance the state of microwave bacteria sensing and microfluidic control and their implications for measuring and interacting with cells and their membrane potentials, which is of great importance for developing new biotechnologically engineered systems and solutions.

scholarly journals Neurotoxic Effect of Flavonol Myricetin in the Presence of Excess Copper

Molecules ◽  
2021 ◽  
Vol 26 (4) ◽  
pp. 845
Author(s):  
Anja Sadžak ◽  
Ignacija Vlašić ◽  
Zoran Kiralj ◽  
Marijana Batarelo ◽  
Nada Oršolić ◽  
...  
Keyword(s):  
Cell Death ◽  
Intracellular Signaling ◽  
Chromatin Condensation ◽  
Membrane Integrity ◽  
Toxic Effects ◽  
Trypan Blue Exclusion ◽  
Atp Production ◽  
Mtt Method ◽  
Biophysical Approach ◽  
Induced Changes

Oxidative stress (OS) induced by the disturbed homeostasis of metal ions is one of the pivotal factors contributing to neurodegeneration. The aim of the present study was to investigate the effects of flavonoid myricetin on copper-induced toxicity in neuroblastoma SH-SY5Y cells. As determined by the MTT method, trypan blue exclusion assay and measurement of ATP production, myricetin heightened the toxic effects of copper and exacerbated cell death. It also increased copper-induced generation of reactive oxygen species, indicating the prooxidative nature of its action. Furthermore, myricetin provoked chromatin condensation and loss of membrane integrity without caspase-3 activation, suggesting the activation of both caspase-independent programmed cell death and necrosis. At the protein level, myricetin-induced upregulation of PARP-1 and decreased expression of Bcl-2, whereas copper-induced changes in the expression of p53, p73, Bax and NME1 were not further affected by myricetin. Inhibitors of ERK1/2 and JNK kinases, protein kinase A and L-type calcium channels exacerbated the toxic effects of myricetin, indicating the involvement of intracellular signaling pathways in cell death. We also employed atomic force microscopy (AFM) to evaluate the morphological and mechanical properties of SH-SY5Y cells at the nanoscale. Consistent with the cellular and molecular methods, this biophysical approach also revealed a myricetin-induced increase in cell surface roughness and reduced elasticity. Taken together, we demonstrated the adverse effects of myricetin, pointing out that caution is required when considering powerful antioxidants for adjuvant therapy in copper-related neurodegeneration.

Sign in / Sign up

Export Citation Format

Share Document