Salt-dependent chromosome viscoelasticity characterized by scanning force microscopy-based volume measurements

Fritzsche, Wolfgang

doi:10.1002/(sici)1097-0029(19990301)44:5<357::aid-jemt7>3.0.co;2-u

Cited by 7 publications

(4 citation statements)

References 16 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…It has emerged as a powerful tool to measure the changes of mechanical property of cell membrane [5,6,8,16-19], cell stiffness [8,17], cell viscoelasticity [20,21], and to measure the interaction between cells [1], by which one could get some valuable information about the biophysical changes of the activated lymphocytes. AFM-based force spectroscopy is also particularly well suited for research in cell adhesion [19], and can stretch cells thereby allowing measurement of their rheological properties [17].…”

Section: Discussionmentioning

confidence: 99%

Membrane Surface Nanostructures and Adhesion Property of T Lymphocytes Exploited by AFM

Cai

et al. 2009

Nanoscale Res Lett

View full text Add to dashboard Cite

The activation of T lymphocytes plays a very important role in T-cell-mediated immune response. Though there are many related literatures, the changes of membrane surface nanostructures and adhesion property of T lymphocytes at different activation stages have not been reported yet. However, these investigations will help us further understand the biophysical and immunologic function of T lymphocytes in the context of activation. In the present study, the membrane architectures of peripheral blood T lymphocytes were obtained by AFM, and adhesion force of the cell membrane were measured by acquiring force–distance curves. The results indicated that the cell volume increased with the increases of activation time, whereas membrane surface adhesion force decreased, even though the local stiffness for resting and activated cells is similar. The results provided complementary and important data to further understand the variation of biophysical properties of T lymphocytes in the context of in vitro activation.

show abstract

Section: Discussionmentioning

confidence: 99%

Membrane Surface Nanostructures and Adhesion Property of T Lymphocytes Exploited by AFM

Cai

et al. 2009

Nanoscale Res Lett

View full text Add to dashboard Cite

show abstract

“…12) Thus, it is possible that EB staining of chromosome preparations may induce structural abnormalities 13) not present in the actual organism. Up to now, though there are some works about structural changes of chromosomes caused by physicochemical treatments, 3,5,6,[14][15][16] however, no previous work has used AFM to examine the effects of time-course of trypsin or different dose EB on chromosomal structures.In this article, we used AFM in the tapping mode to examine chromosomal damage induced by EB treatment and trypsin digestion in air. Our results showed that EB could profoundly damage human chromosomes, leading to breakages and separations in a dose-dependent fashion.…”

mentioning

confidence: 99%

“…5,6) Acetic acid, which is frequently used to remove cellular contaminants, was applied to barley chromosomes at concentrations of 15, 30 and 45%. AFM analysis revealed that the optimal concentration was 30%; at lower levels sufficiently clean chromosomes samples could not obtain and the chromosome surface structures could not be observed, and at higher levels the chromosome structures were significantly damaged, although the cellular contaminants were effectively removed.…”

mentioning

confidence: 99%

mentioning

confidence: 99%

See 1 more Smart Citation

Atomic Force Microscopic Examination of Chromosomes Treated with Trypsin or Ethidium Bromide

Wu¹,

Cai²,

Long-qiu³

et al. 2006

CHEMICAL & PHARMACEUTICAL BULLETIN

View full text Add to dashboard Cite

Recently, researchers have sought to better understand the relationship between chromosomal structure and function. Chromosomes, primarily composed of DNA and histone proteins, must replicate prior to cell division. During replication, errors can be introduced into the DNA via physical or chemical stressors, including heat, ultraviolet radiation, and other forms of radiation, heavy metal ions, drugs and organic reagents.1,2) However, it is also probable that chromosomal alterations might be introduced outside of replication, such as during the trypsinization or ethidium bromide (EB) staining processes 3) commonly used in visualization of chromosomes by optical microscopy. Changes of chromosome ultrastructure cannot be observed clearly under conventional optical microscopes due to technical difficulties such as diffraction limitations. However, the advent of atomic force microscopy (AFM) 4) has allowed researchers to investigate small alterations in chromosome structure and morphology.Previous studies have examined changes in chromosome structure caused by physicochemical treatments.5,6) Acetic acid, which is frequently used to remove cellular contaminants, was applied to barley chromosomes at concentrations of 15, 30 and 45%. AFM analysis revealed that the optimal concentration was 30%; at lower levels sufficiently clean chromosomes samples could not obtain and the chromosome surface structures could not be observed, and at higher levels the chromosome structures were significantly damaged, although the cellular contaminants were effectively removed. 7)Similar studies identified chromosomal damages induced by treatments with NaCl 8) and heavy ion radiation. 9)EB, a heterocyclic organic compound, can insert between base pairs, 10) resulting in increasing DNA rigidity and lengthening of DNA.11) Low doses of EB can induce DNA denaturation and can lead to cancer formation. 12) Thus, it is possible that EB staining of chromosome preparations may induce structural abnormalities 13) not present in the actual organism. Up to now, though there are some works about structural changes of chromosomes caused by physicochemical treatments, 3,5,6,[14][15][16] however, no previous work has used AFM to examine the effects of time-course of trypsin or different dose EB on chromosomal structures.In this article, we used AFM in the tapping mode to examine chromosomal damage induced by EB treatment and trypsin digestion in air. Our results showed that EB could profoundly damage human chromosomes, leading to breakages and separations in a dose-dependent fashion. We also found that trypsinization could obviously change the morphological features of chromosomes with increased digestion time; the optimal digestion time for AFM analysis appeared to be 10-20 s under our experimental conditions, but not to be over 40 s. In addition, our results indicate that AFM is a powerful tool for studying chromosomal damage, perhaps indicating that it will be applicable to further diagnostic applications. Together, our results indicate that common chr...

show abstract

AFM combines functional and morphological analysis of peripheral myelinated and demyelinated nerve fibers

et al. 2007

View full text Add to dashboard Cite

Salt-dependent chromosome viscoelasticity characterized by scanning force microscopy-based volume measurements

Cited by 7 publications

References 16 publications

Membrane Surface Nanostructures and Adhesion Property of T Lymphocytes Exploited by AFM

Membrane Surface Nanostructures and Adhesion Property of T Lymphocytes Exploited by AFM

Atomic Force Microscopic Examination of Chromosomes Treated with Trypsin or Ethidium Bromide

AFM combines functional and morphological analysis of peripheral myelinated and demyelinated nerve fibers

Contact Info

Product

Resources

About