Measurement of Elemental Content and Dry Weight of Single Cells: X-Ray Microanalysis

2018 ◽  
pp. 387-394
Author(s):  
Mikal Heldal
Keyword(s):  
Single Cells ◽  
Dry Weight ◽  
Elemental Content ◽  
X Ray

Correlation of Intracellular Calcium Measurements Using X-Ray Microanalysis and Fluorescence Microscopy Techniques

1989 ◽  
Vol 47 ◽  
pp. 898-899
Author(s):  
H.K. Hagler
Keyword(s):  
Electron Microscope ◽  
Dry Weight ◽  
Elemental Content ◽  
X Ray ◽  
Intensity Measurements ◽  
Inactive Form ◽  
Freeze Dried ◽  
Total Elemental Content ◽  
Microscopy Techniques ◽  
Irreversible Injury

It is my thought that calcium plays a major role in the development of irreversible cellular injury in the myocardium.There are two basic forms of calcium within the cell, the active, ionized calcium and the inactive form which may be bound to cell proteins or held in storage sites within the cells.The use of energy dispersive x-ray microanalysis in an analytical electron microscope permits the localization and measurement of the total elemental content of subcellular regions of cells. These measurements generally require that the cells be cryofixed , cryosectioned, cryotransfered and freeze dried in the electron microscope. The Hall method of continuum normalization is then used to convert the x-ray intensity measurements into dry weight concentrations.Because the cells have to be cryofixed, it is not possible to follow the development of elemental changes within a single cell over time, thus many cells have to be frozen at different time intervals to measure time dependent changes of irreversible injury and cell death. Thus, selected time points are identified and sampled for x-ray microanalysis.

Localisation of hyperaccumulated nickel in Stackhousia tryonii using Electron-probe microanalysis

1996 ◽  
Vol 54 ◽  
pp. 92-93
Author(s):  
I. Noell ◽  
D. Morris
Keyword(s):  
Cross Sections ◽  
Electron Probe ◽  
Dry Weight ◽  
Elemental Content ◽  
X Ray ◽  
Electron Probe Microanalyzer ◽  
Eastern Australia ◽  
Backscattered Electron ◽  
And Function ◽  
Electron Imaging

Proton microprobe and electron probe X-ray microanalysis (EPXMA) simultaneously measure and map elemental content, and hence are excellent tools for investigating the distribution and function of elevated Ni levels in hyperaccumulating plants (Ni concentration >1000 μg g−1 dry weight). Five major hypotheses have been proposed for the function of Ni hyperaccumulation. Our research focuses on the hypothesis that Ni defends against herbivore or pathogen attack and examines the movement of Ni from soil through plant to herbivore in Stackhousia tryonii, the only known hyperaccumulator in eastern Australia. Using a JEOL JXA-840-A electron probe microanalyzer with Moran Scientific Analysis software, we located features of high mean atomic number in whole leaves and cross-sections through backscattered-electron imaging (BEI), then we used EPXMA to identify the elements present and to prepare semi-quantitative x-ray maps of seven key elements.

Preparation of cultured astrocytes for x-ray microanalysis

1989 ◽  
Vol 47 ◽  
pp. 988-989
Author(s):  
N.K.R. Smith ◽  
K.E. Hunter ◽  
P. Mobley ◽  
L.P. Felpel
Keyword(s):  
Cultured Cells ◽  
Elemental Content ◽  
Elemental Distribution ◽  
Sprague Dawley ◽  
X Ray ◽  
Cultured Astrocytes ◽  
Freeze Dried ◽  
Ultimate Objective

Electron probe energy dispersive x-ray microanalysis (XRMA) offers a powerful tool for the determination of intracellular elemental content of biological tissue. However, preparation of the tissue specimen , particularly excitable central nervous system (CNS) tissue , for XRMA is rather difficult, as dissection of a sample from the intact organism frequently results in artefacts in elemental distribution. To circumvent the problems inherent in the in vivo preparation, we turned to an in vitro preparation of astrocytes grown in tissue culture. However, preparations of in vitro samples offer a new and unique set of problems. Generally, cultured cells, growing in monolayer, must be harvested by either mechanical or enzymatic procedures, resulting in variable degrees of damage to the cells and compromised intracel1ular elemental distribution. The ultimate objective is to process and analyze unperturbed cells. With the objective of sparing others from some of the same efforts, we are reporting the considerable difficulties we have encountered in attempting to prepare astrocytes for XRMA.Tissue cultures of astrocytes from newborn C57 mice or Sprague Dawley rats were prepared and cultured by standard techniques, usually in T25 flasks, except as noted differently on Cytodex beads or on gelatin. After different preparative procedures, all samples were frozen on brass pins in liquid propane, stored in liquid nitrogen, cryosectioned (0.1 μm), freeze dried, and microanalyzed as previously reported.

scholarly journals Simultaneously Synchrotron X-ray Fluorescence and Ptychographic Imaging of Frozen Biological Single Cells

2016 ◽  
Vol 22 (S3) ◽  
pp. 90-91 ◽  
Author(s):  
S. Chen ◽  
J. Deng ◽  
Y.S.G. Nashed ◽  
Q. Jin ◽  
D.J. Vine ◽  
...  
Keyword(s):  
Single Cells ◽  
X Ray

Thin-section, freeze-fracture, and energy dispersive x-ray analysis studies of the protein bodies of tomato seeds

1980 ◽  
Vol 58 (6) ◽  
pp. 699-711 ◽  
Author(s):  
Ernest Spitzer ◽  
John N. A. Lott
Keyword(s):  
Freeze Fracture ◽  
Protein Body ◽  
Cell Types ◽  
Energy Dispersive ◽  
Protein Bodies ◽  
Elemental Content ◽  
Tomato Seed ◽  
Endosperm Tissue ◽  
X Ray ◽  
Edx Analysis

Protein bodies of dry seeds of tomato (Lycopersicon esculentum) from radicle, hypocotyl, cotyledon, and endosperm tissue were extensively studied using thin-sectioning, freeze-fracturing and energy dispersive x-ray (EDX) analysis. Protein bodies varied in size, were oval to circular in section, and generally consisted of a proteinaceous matrix, globoid crystal, and protein crystalloid components. Size, shape, and arrangements of globoid crystals and protein crystalloids varied even within the same cell. Globoid crystals were generally oval to circular in section. They were always surrounded by a proteinaceous matrix. In a given protein body the number present ranged from a few to numerous. A protein body generally contained only one protein crystalloid. In section, protein crystalloids were irregular or angular in shape. They were composed of substructural particles which formed lattice planes. EDX analysis of tomato seed globoid crystals revealed the presence of P, K, and Mg in all cases, a fact that is consistent with globoid crystals being phytin-rich. Rarely, small amounts of calcium were found along with P, K, and Mg in globoid crystals of each of the tissue regions considered. The distribution pattern of cells with Ca containing globoid crystals was random. Small amounts of Fe and Mn were also found in the globoid crystals of protein bodies from certain cell types. These two elements, unlike calcium, were specific in terms of their distribution. Globoid crystals from the protodermal cells often contained Mn and Fe. The globoid crystals from provascular tissue of radicle, hypocotyl, and cotyledon regions often contained Fe while globoid crystals in the first layer of large cells surrounding these provascular areas always contained Fe. Results from EDX analysis of the proteinaceous material from the protein bodies are presented and discussed as are variations in elemental content due to different fixations.

scholarly journals Switchable resolution in soft x-ray tomography of single cells

PLoS ONE ◽  
2020 ◽  
Vol 15 (1) ◽  
pp. e0227601 ◽  
Author(s):  
Venera Weinhardt ◽  
Jian-Hua Chen ◽  
Axel A. Ekman ◽  
Jessica Guo ◽  
Soumya G. Remesh ◽  
...  
Keyword(s):  
Single Cells ◽  
X Ray

scholarly journals CT Scans of Single Cells with Soft X-Ray Tomography

2019 ◽  
Vol 116 (3) ◽  
pp. 331a
Author(s):  
Carolyn A. Larabell ◽  
Jian-Hua Chen ◽  
Venera Weinhardt ◽  
Axel Ekman ◽  
Gerry McDermott ◽  
...  
Keyword(s):  
Single Cells ◽  
Ct Scans ◽  
X Ray

THE PHYSIOLOGY OF HOST-PARASITE RELATIONS: IX. FURTHER OBSERVATIONS ON THE ACCUMULATION OF RADIOACTIVE SUBSTANCES AT RUST INFECTIONS

1961 ◽  
Vol 39 (6) ◽  
pp. 1393-1407 ◽  
Author(s):  
Michael Shaw
Keyword(s):  
Specific Activity ◽  
Dry Weight ◽  
Insoluble Fraction ◽  
Pentose Phosphate ◽  
Accumulation Ratio ◽  
X Ray ◽  
Specific Activities ◽  
Leaf Segments ◽  
Wheat Leaves ◽  
Host Parasite

Wang (Can. J. Botany, 38, 635–642 (1960)) concluded that the accumulation of radioactivity observed on radioautographs at infection sites on rusted leaves fed with C14-labelled substances was 'apparent' rather than real. The ‘accumulation ratio’ is defined as the ratio of the specific activities (c.p.m./mg dry weight of intact tissue) of rust-infected to uninfected areas of infected leaves. Theoretical considerations relating to the radioautography of leaves labelled with C14 and to the measurement of ‘accumulation ratios’ by extraction of C14-labelled substances from rusted and uninfected segments of infected leaves, as well as experimental data, show that Wang's conclusion is not generally applicable.Experimentally, it was shown using polymethacrylate C14 sources that differences in distance between sources and X-ray film of the order of 100 μ had no effect on the intensity of autoradiographs. Rust-infected leaves, fed with radioactive glucose, were radiographed between X-ray plates. Localization of radioactivity at infection sites was observed on both ‘dorsal’ and ‘ventral’ radiographs, indicating a real accumulation per unit area. Ventral were more radioactive than dorsal surfaces. The main development of the fungus occurred on the former. Radioautography revealed that C14 from glucose-1-C14, glucose-6-C14, and uniformly labelled glucose fed to excised wheat leaves became localized at 10-day-old rust infections in 2 hours. ‘Accumulation ratios’ calculated from the specific activity of leaf segments remained close to 1.0 for at least 6 hours after introduction of the tracer, but increased to more than 2 after 24 hours. When ‘accumulation ratios’ were calculated from the specific activities of individual pustules (excised with a punch 1 mm in diameter) and interpustular disks, values greater than 1 were observed in 2 hours, thus confirming the results of autoradiography. Differences between the ‘accumulation ratios’ observed with glucose-6-C14 and glucose-1-C14 were consistent with an increased role of the pentose phosphate pathway at infection sites. Incorporation of C14 from uniformly labelled glucose into the alcohol-insoluble fraction of rusted leaf segments was 2.5-fold that in uninfected segments in 6 hours and 3.65-fold in 24 hours. The humin formed during hydrochloric acid hydrolysis accounted for approximately 50% of the activity of the alcohol-insoluble material. The ‘accumulation ratio’ for the alcohol-soluble material was only 1.56 after 24 hours.All the results support the view (Shaw and Samborski, Can. J. Botany, 34, 389–405 (1956)) that there is a quantitative, metabolically dependent accumulation of C14 from radioactive glucose at vigorous rust infections. The relative roles of fungus and host in this process are discussed briefly.

Elemental content of mast cell granules measured by X-ray microanalysis of rat thymic tissue sections

1986 ◽  
Vol 83 (1) ◽  
pp. 77-87 ◽  
Author(s):  
M.D. Kendall ◽  
A. Warley
Keyword(s):  
Mast Cell ◽  
Mast Cells ◽  
Elemental Content ◽  
Thymic Tissue ◽  
X Ray ◽  
Tissue Sections ◽  
Freeze Dried ◽  
The Mean ◽  
Highly Correlated ◽  
The Individual

Mast cell granules were examined by fully quantitative X-ray microanalysis of 20 cells in freeze-dried cryosections. The mast cells were situated mainly in the connective tissue of the thymic capsule of five adult male Carworth Sprague Europe rats. In addition 30 red blood cells were analysed from the same sections. Nineteen of the mast cells had granules rich in S and K. One cell had smaller granules, and in this cell the granules contained high [Ca] and [P] instead of high [S] and [K]. In the majority of cells (13) the S:K ratio was highly correlated and less than 2.2, whereas in the remaining six cells the individual granule ratios were very variable in any one cell and much higher. The mean granule [K] (994 +/− 57 mmol kg-1 dry wt) was about four times the mean cytoplasmic level of 227 +/− 81 mmol kg-1 dry wt. The existence of this difference in concentration between the granules and the cytoplasm suggests that the K in the granules must be bound. The relationship between the [K] and [S] is discussed with regard to the possible binding of heparin and amines in the granules.

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