scholarly journals Quantitative electron probe x-ray microanalysis and densitometric mass determination of individual rat blood platelets.

1985 ◽  
Vol 33 (3) ◽  
pp. 185-190 ◽  
Author(s):  
P W Linders ◽  
R A Van de Vorstenbosch ◽  
A M Stadhouders
Keyword(s):  
Electron Probe ◽  
Blood Platelets ◽  
Dry Mass ◽  
Elemental Content ◽  
Distribution Data ◽  
Rat Blood ◽  
X Ray ◽  
Mass Fractions ◽  
Calcium Magnesium ◽  
The Mean

An improved method for quantitative electron probe X-ray microanalysis of thin biological specimens, introduced recently, has been applied to the elemental analysis of rat blood platelets. The method uses the X-ray signal to quantify the elemental content of an object and electron scattering to determine the total dry mass of the object. Along with the dry mass distribution, data were obtained on the content and mass fraction of calcium, magnesium, and sulfur in 31 individual platelets. The mean platelet dry mass was found to be 985 fg. The mean Ca, Mg, and S contents were 1.80, 3.41, and 18.3 fg, with mean dry mass fractions of 0.195, 0.396, and 1.96%, respectively. Furthermore, these elements appear to be unevenly distributed among the platelet population.

Elemental analysis of individual rat blood platelets by electron probe X-ray microanalysis using a direct quantification method

1985 ◽  
Vol 82 (3) ◽  
pp. 257-261 ◽  
Author(s):  
A. Boekestein ◽  
G. A. J. Kuijpers ◽  
A. L. H. Stols ◽  
A. M. Stadhouders
Keyword(s):  
Elemental Analysis ◽  
Electron Probe ◽  
Blood Platelets ◽  
Rat Blood ◽  
X Ray ◽  
Quantification Method ◽  
Direct Quantification

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.

scholarly journals Application of scanning electron microscopy to x-ray analysis of frozen-hydrated sections. III. Elemental content of cells in the rat renal papillary tip.

1981 ◽  
Vol 88 (2) ◽  
pp. 274-280 ◽  
Author(s):  
R E Bulger ◽  
R Beeuwkes ◽  
A J Saubermann
Keyword(s):  
Water Content ◽  
Collecting Duct ◽  
Dry Mass ◽  
Interstitial Cells ◽  
Elemental Content ◽  
X Rays ◽  
Tissue Mass ◽  
X Ray ◽  
Wet Weight ◽  
Structural Preservation

The electrolyte and water content of cellular and interstitial compartments in the renal papilla of the rat was determined by x-ray microanalysis of frozen-hydrated tissue sections. Papillae from rats on ad libitum water were rapidly frozen in a slush of Freon 12, and sectioned in a cryomicrotome at -30 to -40 degrees C. Frozen 0.5-micrometer sections were mounted on carbon-coated nylon film over a Be grid, transferred cold to the scanning microscope, and maintained at -175 degrees C during analysis. The scanning transmission mode was used for imaging. Structural preservation was of good quality and allowed identification of tissue compartments. Tissue mass (solutes + water) was determined by continuum radiation from regions of interest. After drying in the SEM, elemental composition of morphologically defined compartments (solutes) was determined by analysis of specific x-rays, and total dry mass by continuum. Na, K, Cl, and H2O contents in collecting-duct cells (CDC), papillary epithelial cells (PEC), and interstitial cells (IC) and space were measured. Cells had lower water content (mean 58.7%) than interstitium (77.5%). Intracellular K concentrations (millimoles per kilogram wet weight) were unremarkable (79-156 mm/kg wet weight); P was markedly higher in cells than in interstitium. S was the same in all compartments. Intracellular Na levels were extremely high (CDC, 344 +/- 127 SD mm/kg wet weight; PEC, 287 +/- 105; IC, 898 +/- 194). Mean interstitial Na was 590 +/- 119 mm/kg wet weight. CI values paralleled those for Na. If this Na is unbound, then these data suggest that renal papillary interstitial cells adapt to their hyperosmotic environment by a Na-uptake process.

Strategies For Combining Elemental Distribution Data Derived From Multiple Images and Samples

1998 ◽  
Vol 4 (S2) ◽  
pp. 134-135
Author(s):  
Marie E. Cantino ◽  
Joseph G. Eichen
Keyword(s):  
Electron Probe ◽  
Striated Muscle ◽  
Distribution Data ◽  
Elemental Distribution ◽  
Normalization Procedure ◽  
Multiple Images ◽  
X Ray ◽  
Freeze Dried ◽  
Hall Method ◽  
Elemental Peak

Data from digital electron probe x-ray microanalysis (EPXMA) images can be used to generate high resolution profiles of Ca binding within sarcomeres of vertebrate striated muscle. While ratios of elemental peak to bremstrahlung at each point (Hall method) have been used in many studies to allow comparison of data taken from different samples, this procedure has limitations for our application. A different normalization procedure is described here which provides a means of assessing variation among elemental and bremstrahlung profiles obtained from different images and samples.Freeze dried cryosections of chemically skinned frog or rabbit skeletal muscle were prepared as previously described. Digital EPXMA images were collected for 24 to 36 hours using a Zeiss EM910 STEM and an Oxford ExL2 microanalysis system. Calcium and bremstrahlung counts were summed within one pixel wide masks placed at successive positions along each half sarcomere, as previously described, using an automated routine in IPLAB on a Power Mac 7100.

Tension and electrolyte changes with Na+-K+ pump inhibition in rat papillary muscle

1989 ◽  
Vol 257 (3) ◽  
pp. H942-H953
Author(s):  
D. Parsons ◽  
K. P. Burton ◽  
H. K. Hagler ◽  
J. T. Willerson ◽  
L. M. Buja
Keyword(s):  
Electron Probe ◽  
Cell Injury ◽  
Membrane Integrity ◽  
Bimodal Distribution ◽  
High Energy ◽  
Atp Depletion ◽  
X Ray ◽  
Elemental Concentrations ◽  
Intracellular Ca ◽  
The Mean

Myocardial ischemic injury results in altered membrane integrity, energy depletion, and electrolyte shifts leading to accumulation of intracellular Ca. However, analysis of the direct effects of Ca accumulation is complicated by other concomitant cellular changes produced by ischemia. The purpose of this study was to examine the effects of Ca loading in rat papillary muscles produced by Na+-K+ pump inhibition in oxygenated K+-free buffer. Changes in contractile characteristics, high energy phosphate, and elemental concentrations of subcellular compartments were measured. Electron probe X-ray microanalysis was used to assess elemental concentrations in cryosections. After 3 h of Na+-K+ pump inhibition, resting tension (RT) increased to 164% and developed tension (DT) fell to 16.8% of control values. One hour after return to complete buffer, RT and DT partially recovered but remained significantly different from the 180 to 240-min values for the control muscles. Electron probe X-ray microanalysis showed increases in cytoplasmic and mitochondrial Na and Ca and a decrease in K during Na+-K+ pump inhibition. Mitochondrial Ca was greater than 100-fold greater than Ca in control mitochondria. Morphologically, the majority of cells showed ultrastructural damage. The mean ATP level was 20% of control. After 1 h of recovery, the cells appeared more heterogeneous, and the mean mitochondrial Ca decreased, whereas mean cytoplasmic Ca increased. Further statistical analysis showed a bimodal distribution for Na, Ca, K, Mg, and Cl, which coincided with the morphologically mixed population of cells. This suggests that replacement of extracellular K+ was associated with restored electrolyte gradients in some cells and the persistent or further alteration of electrolytes in others. These results suggest that variable Ca accumulation and associated ATP depletion without the compounding effects of ischemia lead to cell injury similar to reperfusion injury reported in ischemic myocardium.

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.

scholarly journals Dynamic Disorder of Fe3+ Ions in the Crystal Structure of Natural Barioferrite

Minerals ◽  
2018 ◽  
Vol 8 (8) ◽  
pp. 340 ◽  
Author(s):  
Arkadiusz Krzątała ◽  
Taras Panikorovskii ◽  
Irina Galuskina ◽  
Evgeny Galuskin
Keyword(s):  
Crystal Structure ◽  
Electron Probe ◽  
Barium Ferrite ◽  
Stacking Sequence ◽  
Dynamic Disorder ◽  
X Ray ◽  
Bond Lengths ◽  
Trigonal Bipyramidal ◽  
Equatorial Bond ◽  
The Mean

A natural barioferrite, BaFe3+12O19, from a larnite–schorlomite–gehlenite vein of paralava within gehlenite hornfels of the Hatrurim Complex at Har Parsa, Negev Desert, Israel, was investigated by Raman spectroscopy, electron probe microanalysis, and single-crystal X-ray analyses acquired over the temperature range of 100–400 K. The crystals are up to 0.3 mm × 0.1 mm in size and form intergrowths with hematite, magnesioferrite, khesinite, and harmunite. The empirical formula of the barioferrite investigated is as follows: (Ba0.85Ca0.12Sr0.03)∑1(Fe3+10.72Al0.46Ti4+0.41Mg0.15Cu2+0.09Ca0.08Zn0.04Mn2+0.03Si0.01)∑11.99O19. The strongest bands in the Raman spectrum are as follows: 712, 682, 617, 515, 406, and 328 cm−1. The structure of natural barioferrite (P63/mmc, a = 5.8901(2) Å, c = 23.1235(6) Å, V = 694.75(4) Å3, Z = 2) is identical with the structure of synthetic barium ferrite and can be described as an interstratification of two fundamental blocks: spinel-like S-modules with a cubic stacking sequence and R-modules that have hexagonal stacking. The displacement ellipsoids of the trigonal bipyramidal site show elongation along the [001] direction during heating. As a function of temperature, the mean apical Fe–O bond lengths increase, whereas the equatorial bond lengths decrease, which indicates dynamic disorder at the Fe2 site.

Labelling of Blood Platelets with Stable Tracers

1980 ◽  
Vol 44 (01) ◽  
pp. 030-031 ◽  
Author(s):  
D Del Principe ◽  
R Cesareo ◽  
B M Tallarida ◽  
M G Ciancarelli ◽  
M Ricci ◽  
...  
Keyword(s):  
Blood Platelets ◽  
Half Time ◽  
Simple Version ◽  
X Ray ◽  
Rabbit Platelets ◽  
Stable Tracers ◽  
The Mean

SummaryHalf-time values of platelets labelled with stable rubidium are compared to those of platelets labelled with Cr51. Platelets labelled with stable rubidium are assayed by a very simple version of the X-Ray fluorescence equipment. The mean quantity of rubidium incorporated by the cells is of about some µg Rb per ml blood.The in vitro half-time of human Rb labelled platelets stored at 22° C is 41.2 ± 3h compared with the value 44.8 ± 3h for platelets labelled with Cr51, as deduced by six experiments. The in vivo half-time of rabbit platelets labelled with stable rubidium is 22 ± 3h compared with the value 18 ± 3h of platelets labelled with Cr51; ten experiments were carried out.

A New Model For Electron Probe Quantification

1999 ◽  
Vol 5 (S2) ◽  
pp. 72-73
Author(s):  
John J. Donovan ◽  
Nicholas E. Pingitore ◽  
Raymond Jeanloz
Keyword(s):  
Electron Probe ◽  
Mass Fraction ◽  
Mass Concentration ◽  
Incident Beam ◽  
Characteristic Radiation ◽  
Beam Electron ◽  
X Ray ◽  
First Approximation ◽  
Mass Fractions ◽  
Image Position

Castaing’s first approximation assumes that the characteristic radiation emitted by each element in a compound is unaffected by the presence of the other elements, and that the intensity of the radiation emitted by each element in the compound is proportional to its mass concentration. From Castaing’s first approximation based on mass fractions, the initial estimate of the concentration of an element in a compound iswhere C and C° are mass fractions in the sample and standard, and I and I° are x-ray emission intensities of a specific transition measured in the sample and the standard. Surprisingly, the mass fraction approach works well in practice, even though it lacks any obvious physical basis. This can be understood by considering that for typical energies involved in EPMA (50 keV or less), the size of the nucleus is several orders of magnitude smaller than the average incident beam electron wavelength.

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