scholarly journals Mitotic Chromosomes in Live Cells Characterized Using High-Speed and Label-Free Optical Diffraction Tomography

Cells ◽  
2019 ◽  
Vol 8 (11) ◽  
pp. 1368 ◽  
Author(s):  
Kim ◽  
Lee ◽  
Fujii ◽  
Lee ◽  
Lee ◽  
...  
Keyword(s):  
Diffusion Coefficient ◽  
Three Dimensional ◽  
Laser Scanning Microscopy ◽  
Optical Diffraction ◽  
Live Cells ◽  
Confocal Laser ◽  
Diffraction Tomography ◽  
Label Free ◽  
Mitotic Chromosomes ◽  
Optical Diffraction Tomography

The cell nucleus is a three-dimensional, dynamic organelle organized into subnuclear compartments such as chromatin and nucleoli. The structure and function of these compartments are maintained by diffusion and interactions between related factors as well as by dynamic and structural changes. Recent studies using fluorescent microscopic techniques suggest that protein factors can access and are freely mobile in heterochromatin and in mitotic chromosomes, despite their densely packed structure. However, the physicochemical properties of the chromosome during cell division are not fully understood. In the present study, characteristic properties such as the refractive index (RI), volume of the mitotic chromosomes, and diffusion coefficient (D) of fluorescent probes inside the chromosome were quantified using an approach combining label-free optical diffraction tomography with complementary confocal laser-scanning microscopy and fluorescence correlation spectroscopy. Variations in these parameters correlated with osmotic conditions, suggesting that changes in RI are consistent with those of the diffusion coefficient for mitotic chromosomes and cytosol. Serial RI tomography images of chromosomes in live cells during mitosis were compared with three-dimensional confocal micrographs to demonstrate that compaction and decompaction of chromosomes induced by osmotic change were characterized by linked changes in chromosome RI, volume, and the mobilities of fluorescent proteins.

scholarly journals Physicochemical Properties of Chromosomes in Live Cells Characterized by Label-Free Imaging and Fluorescence Correlation Spectroscopy

2019 ◽  
Author(s):  
Tae-Keun Kim ◽  
Byong-Wook Lee ◽  
Fumihiko Fujii ◽  
Kee-Hang Lee ◽  
YongKeun Park ◽  
...  
Keyword(s):  
Physicochemical Properties ◽  
Fluorescence Correlation Spectroscopy ◽  
Three Dimensional ◽  
Correlation Spectroscopy ◽  
Laser Scanning Microscopy ◽  
Optical Diffraction ◽  
Live Cells ◽  
Label Free ◽  
Mitotic Chromosomes ◽  
Fluorescence Correlation

AbstractThe cell nucleus is a three-dimensional, dynamic organelle that is organized into many subnuclear bodies, such as chromatin and nucleoli. The structure and function of these bodies is maintained by diffusion and interactions between related factors as well as dynamic and structural changes. Recent studies using fluorescent microscopic techniques suggest that protein factors can access and are freely mobile in mitotic chromosomes, despite their densely packed structure. However, the physicochemical properties of the chromosome itself during cell division are not yet fully understood. Physical parameters, such as the refractive index (RI), volume of the mitotic chromosome, and diffusion coefficients of fluorescent probes inside the chromosome were quantified using an approach combining label-free optical diffraction tomography with complementary confocal laser scanning microscopy and fluorescence correlation spectroscopy. Variance in these parameters correlated among various osmotic conditions, suggesting that changes in RI are consistent with those in the diffusion coefficient for mitotic chromosomes and cytosol. Serial RI tomography images of chromosomes in live cells during mitosis were compared with three-dimensional confocal micrographs to demonstrate that compaction and decompaction of chromosomes induced by osmotic change were characterized by linked changes in chromosome RI, volume, and the mobility of fluorescent proteins.

scholarly journals Three-dimensional label-free observation of individual bacteria upon antibiotic treatment using optical diffraction tomography

2019 ◽  
Author(s):  
Jeonghun Oh ◽  
Jea Sung Ryu ◽  
Moosung Lee ◽  
Jaehwang Jung ◽  
Seung yun Han ◽  
...  
Keyword(s):  
Imaging Techniques ◽  
Three Dimensional ◽  
Time Lapse ◽  
Optical Diffraction ◽  
Response Analysis ◽  
Diffraction Tomography ◽  
Label Free ◽  
Optical Diffraction Tomography ◽  
Quantitative Manner ◽  
Basic Studies

AbstractMeasuring alterations in bacteria upon antibiotic application is important for basic studies in microbiology, drug discovery, and clinical diagnosis, and disease treatment. However, imaging and 3D time-lapse response analysis of individual bacteria upon antibiotic application remain largely unexplored mainly due to limitations in imaging techniques. Here, we present a method to systematically investigate the alterations in individual bacteria in 3D and quantitatively analyze the effects of antibiotics. Using optical diffraction tomography, in-situ responses of Escherichia coli and Bacillus subtilis to various concentrations of ampicillin were investigated in a label-free and quantitative manner. The presented method reconstructs the dynamic changes in the 3D refractive-index distributions of living bacteria in response to antibiotics at sub-micrometer spatial resolution.

scholarly journals Label-free three-dimensional observations and quantitative characterisation of on-chip vasculogenesis using optical diffraction tomography

2020 ◽  
Author(s):  
Chungha Lee ◽  
Seunggyu Kim ◽  
Herve Hugonnet ◽  
Moosung Lee ◽  
Weisun Park ◽  
...  
Keyword(s):  
Three Dimensional ◽  
Optical Diffraction ◽  
Diffraction Tomography ◽  
Label Free ◽  
Vascular Networks ◽  
Optical Diffraction Tomography ◽  
Quantitative Characterisation ◽  
Vascular Structures ◽  
On Chip ◽  
Intrinsic Imaging

Label-free, three-dimensional (3D) quantitative observations of on-chip vasculogenesis were achieved using optical diffraction tomography. Exploiting 3D refractive index maps as an intrinsic imaging contrast, the vascular structures, multicellular activities, and subcellular organelles of endothelial cells were imaged and analysed throughout vasculogenesis to characterise mature vascular networks without exogenous labelling.

scholarly journals Three-dimensional label-free observation of individual bacteria upon antibiotic treatment using optical diffraction tomography

2020 ◽  
Vol 11 (3) ◽  
pp. 1257 ◽  
Author(s):  
Jeonghun Oh ◽  
Jea Sung Ryu ◽  
Moosung Lee ◽  
Jaehwang Jung ◽  
SeungYun Han ◽  
...  
Keyword(s):  
Antibiotic Treatment ◽  
Three Dimensional ◽  
Optical Diffraction ◽  
Diffraction Tomography ◽  
Label Free ◽  
Optical Diffraction Tomography

scholarly journals Correlative three-dimensional fluorescence and refractive index tomography: bridging the gap between molecular specificity and quantitative bioimaging

2017 ◽  
Author(s):  
Kyoohyun Kim ◽  
Wei Sun Park ◽  
Sangchan Na ◽  
Sangbum Kim ◽  
Taehong Kim ◽  
...  
Keyword(s):  
Refractive Index ◽  
Three Dimensional ◽  
Optical Diffraction ◽  
Live Cells ◽  
Specific Information ◽  
Label Free ◽  
Optical Diffraction Tomography ◽  
Molecular Specificity ◽  
3D Fluorescence Microscopy ◽  
Nih 3T3

AbstractOptical diffraction tomography (ODT) provides label-free three-dimensional (3D) refractive index (RI) measurement of biological samples. However, due to the nature of the RI values of biological specimens, ODT has limited access to molecular specific information. Here, we present an optical setup combining ODT with three-channel 3D fluorescence microscopy, to enhance the molecular specificity of the 3D RI measurement. The 3D RI distribution and 3D deconvoluted fluorescence images of HeLa cells and NIH-3T3 cells are measured, and the cross-correlative analysis between RI and fluorescence of live cells are presented.

scholarly journals Physicochemical Properties of Nucleoli in Live Cells Analyzed by Label-Free Optical Diffraction Tomography

Cells ◽  
2019 ◽  
Vol 8 (7) ◽  
pp. 699 ◽  
Author(s):  
Kim ◽  
Lee ◽  
Fujii ◽  
Kim ◽  
Pack
Keyword(s):  
Physicochemical Properties ◽  
Nuclear Bodies ◽  
Laser Scanning Microscopy ◽  
Atp Depletion ◽  
Optical Diffraction ◽  
Physical Parameters ◽  
Diffraction Tomography ◽  
Label Free ◽  
Molecular Density ◽  
Optical Diffraction Tomography

The cell nucleus is three-dimensionally and dynamically organized by nuclear components with high molecular density, such as chromatin and nuclear bodies. The structure and functions of these components are represented by the diffusion and interaction of related factors. Recent studies suggest that the nucleolus can be assessed using various protein probes, as the probes are highly mobile in this organelle, although it is known that they have a densely packed structure. However, physicochemical properties of the nucleolus itself, such as molecular density and volume when cellular conditions are changed, are not yet fully understood. In this study, physical parameters such as the refractive index (RI) and volume of the nucleoli in addition to the diffusion coefficient (D) of fluorescent probe protein inside the nucleolus are quantified and compared by combining label-free optical diffraction tomography (ODT) with confocal laser scanning microscopy (CLSM)-based fluorescence correlation spectroscopy (FCS). 3D evaluation of RI values and corresponding RI images of nucleoli in live HeLa cells successfully demonstrated varying various physiological conditions. Our complimentary method suggests that physical property of the nucleolus in live cell is sensitive to ATP depletion and transcriptional inhibition, while it is insensitive to hyper osmotic pressure when compared with the cytoplasm and nucleoplasm. The result demonstrates that the nucleolus has unique physicochemical properties when compared with other cellular components.

scholarly journals 3D label-free imaging and analysis of Pinus pollen grains using optical diffraction tomography

2017 ◽  
Author(s):  
Geon Kim ◽  
SangYun Lee ◽  
Seungwoo Shin ◽  
YongKeun Park
Keyword(s):  
Refractive Index ◽  
Three Dimensional ◽  
Pollen Grains ◽  
Reproductive Function ◽  
Optical Diffraction ◽  
List Type ◽  
Diffraction Tomography ◽  
Label Free ◽  
Optical Diffraction Tomography ◽  
Index Maps

SummaryThe structure of pollen grains is related to the reproductive function of the plants. Here, three-dimensional (3D) refractive index maps were obtained for individual conifer pollen grains using optical diffraction tomography (ODT).The 3D morphological features of pollen grains from pine trees were investigated using measured refractive index maps, in which distinct substructures were clearly distinguished and analyzed.Morphological and physiochemical parameters of the pollen grains were quantified from the obtained refractive index (RI) maps and used to quantitatively study the interspecific differences of pollen grains from different strains.Our results demonstrate that ODT can assess the structure of pollen grains. This label-free and rapid 3D imaging approach may provide a new platform for understanding the physiology of pollen grains.

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