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PubMed1981

X-ray microanalysis of non-aldehyde-fixed glycogen contrast stained with OsVIIIO4, OsVIIIFeIII, or OsVIFeII complex in vitro.

Fibrin-enrobed, commercially produced glycogen was treated, without prior glutaraldehyde fixation, to a form of post-fixation with solutions of OsVIIIO4 or with a mixture of either OsVIIIO4 plus K3FeIII(CN)6 or K2OsVIO4 plus K4FeII(CN)6. Only the last mixture gave contrast staining of the glycogen in unstained ultrathin sections. The first mixture rendered the glycogen just barely visible but the glycogen contrast was increased by lead staining. The glycogen treated with the OsVIIIO4 solution was not contrast stained an was just observable after lead staining. Qualitative X-ray microanalysis of the glycogen in the ultrathin sections confirmed the presence of osmium and iron in the glycogen treated with both mixtures. The glycogen treated with OsVIIIO4 alone was difficult to analyse. Quantitative X-ray microanalysis showed that, in the glycogen treated with the OsVIIIO4 mixture plus K3FeIII(CN)6, the mean atomic osmium to iron ratio was 1:5. In the glycogen treated with K2OsVIO4 plus K4FeII(CN)6, this ratio was 1:17. However, th mean net osmium intensity in the latter case was 15 times higher than in the former case and for the iron even 40 times higher.

Animals↗

PubMed2003

Research of the entry of rare earth elements Eu3+ and La3+ into plant cell.

Whether rare earth elements can enter into plant cells remains controversial. This article discusses the ultracellular structural localization of lanthanum (La(3+)) and europium (Eu(3+)) in the intact plant cells fed by rare earth elements Eu(3+) and La(3+). Eu-TTA fluorescence analysis of the plasmalemma, cytoplast, and mitochondria showed that Eu(3+) fluorescence intensities in such structures significantly increased. Eu(3+) can directly enter or be carried by the artificial ion carrier A23187 into plant cells through the calcium ion (Ca(2+)) channel and then partially resume the synthesis of amaranthin in the Amaranthus caudatus growing in the dark. Locations of rare earth elements La(3+) and Eu(3+) in all kinds of components of cytoplasmatic organelles were determined with transmission electron microscope, scanning electron microscope, and energy-dispersive X-ray microanalysis. The results of energy-dispersive X-ray microanalysis indicated that Eu(3+) and La(3+) can be absorbed into plant cells and bind to the membranes of protoplasm, chloroplast, mitochondrion, cytoplast, and karyon. These results provide experimental evidence that rare earth elements can be absorbed into plant cells, which would be the basis for interpreting physiological and biochemical effects of rare earth elements on plant cells.

Cations↗

PubMed1995

Sodium phosphate crystals in chondromalacic patellar cartilage.

We report the finding of sodium- and phosphorus-based crystallisation in abnormal human articular cartilage. We prepared five chondromalacic, five osteoarthritic and four macroscopically normal specimens of patellar cartilage by a cryofracturing technique and examined them in a scanning electron microscope. An energy-dispersive X-ray microanalysis system was used to identify the crystals, which were found in only three of the five chondromalacic specimens. Star-shaped crystals were seen either individually or in clusters in the matrix of the cartilage. They consisted of sodium and phosphorus, and we have found no previous reports of such findings. The calcified zone, the bone, and the articular surface were free from crystals.

Adult↗

PubMed2006

SEM-EDS probing of morphological and physiological changes produced by a porphyrin photosensitizer in Psammobatis extenta electrocytes.

Morphological and physiological changes produced by the intracellular localization of an alkyl long-chain tetraphenylporphyrin photosensitizer in Psammobatis extenta electrocytes were studied by means of SEM-EDS. Immediately after photosensitizer penetration, electrocytes swell and their convex faces lose all invaginations. This effect is due to chloride and sodium ion flux into electrocytes, in accordance with energy dispersive X-ray microanalysis.

Animals↗

PubMed2003

Eradication of Propionibacterium acnes by its endogenic porphyrins after illumination with high intensity blue light.

Propionibacterium acnes is a Gram-positive, microaerophilic bacterium that causes skin wounds. It is known to naturally produce high amounts of intracellular porphyrins. The results of the present study confirm that the investigated strain of P. acnes is capable of producing endogenic porphyrins with no need for any trigger molecules. Extracts from growing cultures have demonstrated emission peaks around 612 nm when excited at 405 nm, which are characteristic for porphyrins. Endogenic porphyrins were determined and quantified after their extraction from the bacterial cells by fluorescence intensity and by elution retention time on high-performance liquid chromatography (HPLC). The porphyrins produced by P. acnes are mostly coproporphyrin, as shown by the HPLC elution patterns. Addition of delta-aminolevulinic acid (ALA) enhanced intracellular porphyrin synthesis and higher amounts of coproporphyrin have been found. Eradication of P. acnes by its endogenic porphyrins was examined after illumination with intense blue light at 407-420 nm. The viability of 24 h cultures grown anaerobically in liquid medium was reduced by less than two orders of magnitude when illuminated once with a light dose of 75 J cm(-2). Better photodynamic effects were obtained when cultures were illuminated twice or three times consecutively with a light dose of 75 J cm(-2) and an interval of 24 h between illuminations. The viability of the culture under these conditions decreased by four orders of magnitude after two illuminations and by five orders of magnitude after three illuminations. When ALA-triggered cultures were illuminated with intense blue light at a light dose of 75 J cm(-2) the viability of the treated cultures decreased by seven orders of magnitude. This decrease in viability can occur even after a single exposure of illumination for the indicated light intensity. X-ray microanalysis and transmission electron microscopy revealed structural damages to membranes in the illuminated P. acnes. Illumination of the endogenous coproporphyrin with blue light (407-420 nm) apparently plays a major role in P. acnes photoinactivation. A treatment protocol with a series of several illuminations or illumination after application of ALA may be suitable for curing acne. Treatment by both pathways may overcome the resistance of P. acnes to antibiotic treatment.

Acne Vulgaris↗

PubMed1979

Electron microscopy of unstained, fresh air-dried spreads of the mouse brain and application to energy dispersive X-ray microanalysis.

Electron microscopy of unstained, fresh air-dried spreads of the mouse brain revealed well-preserved ultrastructures of neurons and synaptic boutons filled with synaptic vesicles. Energy dispersive X-ray microanalysis of the neuron nucleus disclosed peaks for phosphorus, sulfur, chlorine and potassium. Analysis of large regions (spots of ca. 1 micron in diameter) on the neuron nucleus revealed peaks for magnesium, whereas that of regions on the cytoplasm rarely disclosed the element, which was confirmed by removal of the background noise using a micro-Edit computer system. Analysis of regions on synaptic boutons except mitochondria also indicated peaks for magnesium.

Animals↗

PubMed1982

Electron microscopy and x-ray microanalysis of calcium-binding sites of the plasma membrane of Beroe giant smooth muscle fibre.

When they are fixed with glutaraldehyde in the presence of calcium ions, the plasma membranes of Beroe giant smooth muscle fibres display micropapillae filled with an electron-dense deposit. After freeze-fracturing of fixed tissue, the micropapillae are still present, therefore their shape and size are determined during or before glutaraldehyde fixation, and are not due to rearrangement during subsequent steps of tissue processing; intramembranous particles are seen at the periphery rather than at the top of micropapillae. In conventional stained sections, the surface of most micropapillae is surrounded by fine fibrils; when the fuzzy coat is separated from the muscle cell by a clear space, this fibrillar material becomes conspicuous and links the micropapillae to the coat. After calcium-free (EGTA) fixation, the plasma membrane is completely free of electron-dense sites but "empty' micropapillae can be seen. X-ray microanalysis of single electron-dense deposits by wavelength-dispersive spectrometry reveals a high calcium content. A weak osmiophily is suspected, but does not seem to interfere with this analysis of calcium. The highest peak-to-background ratios for calcium were obtained using the smallest aperture of the Wehnelt of the analytical microscope. In the Discussion, the micropapillae are compared to similar structures described by other authors in a variety of cell types.

Animals↗

PubMed1987

Low temperature techniques in biomedical microanalysis.

Many diseases are associated with a change in the distribution of diffusible ions at the cell or tissue level. These diseases can profitably be studied by X-ray microanalysis. This technique for the study of ion distribution requires the use of cryoprepared specimens. Analysis at low or medium resolution can be carried out on thick or semi-thick cryosections, or on frozen-hydrated or freeze-dried embedded bulk samples. Such analyses are particularly useful in the initial stages of an investigation, or when many data from a large number of samples have to be acquired. Quantitative analysis is then usually carried out with the peak-to-local background method: by taking the background in the same energy range as the characteristic peak, an intrinsic correction for absorption of X-rays within the sample is made. X-ray microanalysis of cultured cells prepared by freeze-drying can also be carried out in this way. Analysis at high resolution has to be carried out on thin sections: cryosections, or sections of freeze-substituted or freeze-dried embedded tissue. For the latter type of specimens, the use of low-temperature embedding methods may have important advantages. Quantitative analysis of thin sections is carried out by the established continuum method.

Animals↗

PubMed2005

Possible etiology of calculi formation in salivary glands: biophysical analysis of calculus.

Sialolithiasis is one of the common diseases of the salivary glands. It was speculated that, in the process of calculi formation, degenerative substances are emitted by saliva and calcification then occurs around these substances, and finally calculi are formed. However, the exact mechanism of the formation of calculi is still unclear. In this study, we identify some possible etiologies of calculi formation in salivary glands through biophysical analysis. Calculi from 13 patients with submandibular sialolithiasis were investigated by transmission electron microscopy, scanning electron microscopy, X-ray microanalyzer, and electron diffraction. Transmission electron microscopic observation of calculi was performed in the submandibular gland (n = 13). In 3 of the 13 cases, a number of mitochondria-like structures and lysosomes were found near calcified materials. Scanning electron microscopic examination of these materials revealed that there were lamellar and concentric structures and that the degree of calcification was different among the calculi. X-ray microanalysis disclosed the component elements in the calculi to be Ca, P, S, Na, etc., and the main constituents were Ca and P. The calcium-to-phosphorus ratio was 1.60-1.89. Analysis of the area including mitochondria-like structures, lysosomes, and the fibrous structures by electron diffraction revealed the presence of hydroxyapatite and calcified materials. It is speculated that mitochondria and lysosomal bodies from the ductal system of the submandibular gland are an etiological source for calcification in the salivary gland.

Electron Probe Microanalysis↗

PubMed1986

Generalized argyrosis in man: neurotological, ultrastructural and X-ray microanalytical findings.

Generalized argyrosis can produce a number of abnormalities, including skin discoloration, liver and kidney dysfunction. We describe a patient with generalized argyrosis following long-term self-treatment with oral silver intake, in whom skin discoloration, progressive taste and smell disorders, vertigo and hypesthesia were observed. These findings were confirmed by chemosensory tests and electrophysiological investigations. The development of hypogeusia was assessed by subjective tests, while the progression of hyposmia was followed by recording olfactory evoked cortical potentials. Light and electron microscopy of tissue samplings demonstrated electron-dense mineral deposits in basal membranes, in macrophages, in the perineurium of peripheral nerves, along elastic and collagenous fibers, and in necrotic cells of the oral submucosa. Silver and sulfur deposits in affected tissues could be defined by X-ray microanalysis. The quantitative ratio between silver and sulfur in involved tissues was similar to that of an inorganic silver-sulfide (Ag2S) standard. The minute increase in the sulfur content when compared to the inorganic standard suggested a sulfur containing organic matrix of the tissue precipitates. Our findings indicate that the affinity of silver for membrane and neuronal structures and the deposition of silver as an insoluble compound (Ag2S) induce the progression of clinical disease.

Ageusia↗

PubMed1987

The occurrence of metals Al, Fe, Ni, Cu, Zn in the nuclei of animal cells: an ultrastructural, in situ, X-ray microanalytical study.

Cell nuclei may contain significant quantities of the metals Fe, Ni, Cu, Zn, since they are present in the nucleo-enzymes and/or nucleic acids. These metals have been detected by X-ray microanalysis in situ in dinoflagellates (Kearns et al). Aluminum was only detected in cell nuclei in cases of natural or provoked intoxication. We observed at the ultrastructural level, in situ, the presence of Al, Fe, Ni, Cu, Zn in nuclei of different types of non-intoxicated animal cells. Moreover, we measured the concentration of these metals in the nucleolus and chromatin and compared it with the concentration of P and S.

Aluminum↗

PubMed1993

Microanalytical studies of metal localization in biological tissues by environmental SEM.

The presence and distribution of Al and Mn in floral and seed tissues of eucalypts from Al-contaminated soils was analyzed using energy-dispersive X-ray microanalysis (EDS) in an environmental scanning electron microscope (ESEM). EDS by ESEM determined the distribution of elements between tissue types was suitable for intact samples or those with lower available moisture or intact specimens. The analytical technique was not appropriate for highly vascular samples. Other factors influencing the detection of elements by ESEM-EDS were electron scattering and the relative concentration and localization of elements within the tissues. EDS-detectable levels were significantly correlated with tissue concentrations determined by atomic absorption spectrophotometry for Mn but not for Al.

Aluminum↗

PubMed2006

Effect of mineral elements on phosphorus release from heated sewage sludge.

The aim of this work was to examine the influence of mineral elements on phosphorus (P) release from heated waste sludges. Energy dispersive X-ray microanalysis suggested that P was associated with Al, Ca, and Mg on the surface of waste sludge biomass obtained from six wastewater treatment plants. The extent of P release decreased with increasing the total concentrations of Al, Mg, and Ca in waste sludges. The addition of Al2(SO4)3, Ca(OH)2, CaCl2, MgSO4, or NaAlO2 to activated sludges, which were taken from a bench-scale EBPR process, reduced the P release significantly.

Electron Probe Microanalysis↗

PubMed1997

Microwave fixation and localization of calcium in synaptic terminals using x-ray microanalysis and electron energy loss spectroscopy imaging.

The distribution of calcium ions is demonstrated in synaptic terminals by means of a two-step chemical precipitation of calcium ions in the rat brain. K-oxalate/K-antimonate chemical replacement with simultaneous computerized microwave irradiation was used. This precipitate in nerve cell structures was investigated by computerized electron probe x-ray microanalysis (EDX) and electron energy loss spectroscopic (EELS) imaging. The values obtained by EDX agreed with those of the standard sample and theoretical values of Ca-antimonate. Typical EELS spectra of Ca:L, O:K, and Sb:M were obtained from nerve terminals in the same tissue block as that used for EDX analysis. Excellent net Ca:L and Sb:M EELS digital images were obtained after their background images were subtracted. Calcium ions were distributed in the nerve terminals, synaptic vesicles, mitochondria, and synaptic membranes.

Animals↗

PubMed2001

Utilization of yolk platelets during early embryonic development of Rana temporaria and Bufo bufo.

Utilization of yolk platelets in cleaving embryos of Rana temporaria and Bufo bufo was studied by different methods. Morphological observations of yolk platelets of R. temporaria embryos at tail bud stage by transmission electron microscopy indicated four initial phases of platelet degradation. The pattern of these events is similar to that found in embryos of B. bufo. The morphological observations were confirmed by energy-dispersive X-ray microanalysis of the elemental content of platelets and by selected-area electron diffraction of platelet cores. Covalently bound sulphur content decreased during cleavage and the content of different inorganic ions changed, whereas the structure of crystalline core remained constant. Morphological changes found in the amorphous cortex of yolk platelets were due to their utilization. Stereological measurements indicated that utilization during cleavage increased, but only the initial phases of yolk platelet degradation were seen. The volume of the cortex did not decrease and the crystalline core did not fragment.

Animals↗

PubMed1992

Human neutrophil response to short-term exposure to F-75 cobalt-based alloy.

The effect of biomaterials on the activation of human neutrophils was studied. Human neutrophils were incubated with F-75 cobalt-based alloy or polystyrene microspheres of a nonphagocytosable size with two times total neutrophil plane surface area. Scanning and transmission electron microscope (SEM, TEM), energy dispersive x-ray microanalysis (EDX), and graphite furnace atomic absorption spectroscopy (GFAAS) were used to analyze changes in cellular morphology and metal content. This report presents evidence that human PMNs display morphological changes related to foreign material challenge, including activation on F-75 bead surfaces, pinocytosis of corrosion products, formation of intracellular vacuoles, degranulation, etc. Moreover, when PMNs were present, the corrosion release rate of F-75 increased as much as three times over cell-free controls.

Adult↗

PubMed1999

[Dentinogenesis imperfecta. Scanning electron microscopic study and microanalysis].

BACKGROUND: Dentinogenesis imperfecta (DI) is an inherited dentine defect which affects both the primary and secondary dentitions. Shields et al. in 1973 suggested a classification of DI within three types: type I, associated with osteogenesis imperfecta (OI), type II and type III. Although the varying clinical, radiographic and histological findings in DI have been described in detail, an available method for closer examination of the abnormal dentine matrix, electron microscopy, has seldom been used. Scanning and transmission electron microscopy studies can help to understand the pathogenesis of the different types of heritable dentine defects and the diagnosis and classification of these diseases. The aim of the present study was to evaluate a case of DI using scanning electron microscopy and microanalysis. METHODS: Dentine was obtained from tooth samples from a fourteen-year-old boy affected by DI and from third molars extracted for therapeutic reasons used as controls. Samples were observed with a scanning electron microscope, scanning electron micrographs were evaluated with an image analysis program and specimens were finally observed with a scanning electron microscope equipped for micro-analysis. RESULTS AND CONCLUSIONS: The results obtained showed that the total number of dentinal tubules was significantly reduced and the presence of a dentine mineralization defect in the patient affected by DI, in comparison to the controls.

Adolescent↗

PubMed1997

[Changes in morphology and calcium content of otoconia in rats after 120 d tail-suspension].

The morphology and calcium content of otoconia in rats after long term (120 d) tail-suspension were studied using scanning electron microscopy (SEM) and X-ray microanalysis, respectively. The results showed that after 120 d simulated weightlessness otoconia were round, irregularly shaped, or with fissures, and there were rough and fine granular or small globular substances on the surface. X-ray microanalysis showed that the calcium content in the otoconia of both utricule and saccule was significantly decreased in the 120 d tail-suspended rats than that in control (P < 0.01). These results suggest that a long term(120 d) simulation of the headward distribution of blood volume and hindlimb underloading effect induced by weightlessness may cause the morphological changes and lower calcium content of the otoconia. Finally, the possible mechanism and the physiologic meaning of these findings are discussed.

Animals↗