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PubMed1980

Comparison of analytic techniques: chemical, isotopic, and microprobe analyses.

The development of new techniques and modifications to existing methods are providing important information about cellular water and electrolytes in relation to transepithelial transport. Information obtained for one epithelium, the toad urinary bladder, from chemical analyses, isotopic studies, and electron microprobe analysis, is reviewed. Chemical and isotopic analyses allow estimation of average cellular water and ion contents and determination of the origin of ions from the media bathing the mucosal and basolateral cellular membranes. The electron microprobe provides additional information about the distributions of ions between the cell types that constitute the epithelial layer and also allows some measurement of ion distributions within individual cells. In toad urinary bladder epithelial cells there is broad agreement between the results obtained with these different techniques and a summary is provided of possible relationships between transepithelial sodium transport and cellular composition.

Animals↗
PubMed1982

Ultrastructure and electron-probe x-ray analysis of the pigment in melanosis duodeni.

A patient with peptic ulceration developed melanosis duodeni, which was studied by light microscopy, histochemistry, electron microscopy and electron-probe x-ray analysis. Our studies show that the pigment in melanosis duodeni resides in the lysosomes of macrophages in the lamina propria. The pigment is not melanin or a melanin-like compound as has been claimed by previous workers. On the basis of electron-probe x-ray analytical findings we have concluded that the pigment is essentially FeS. On the basis of the history of this patient and cases reported in the literature we think that the Fe in this pigment is derived from haemorrhage in the gastrointestinal tract. We also found small amounts of Ca, K, Al, Mg, Si, and Ag. It would appear that Al, Mg and Si were probably derived from the biological milieu and/or other drugs and/or food and/or specimen contamination.

Cytoplasmic Granules↗
PubMed1982

[Electron microprobe ultrastructural localization of aluminium in hepatocytes (authors' transl)].

Liver tissue of a female patient who died of dialysis encephalopathy with aluminium intoxication was studied by electron microscopy and X-ray microprobe analysis. Aluminium was present in high concentrations in lipofuscin granules of hepatocytes and associated with severe lesions of most hepatic cells. The Küpffer cells, however, were normal. A similar study conducted in rats intoxicated by soluble aluminium salts showed that aluminium begins to concentrate in the lysosomes of hepatocytes, where it combines with phosphorus to form an insoluble salt.

Adult↗
PubMed1981

Ultrastructural analysis and quantitative distribution of Macro-and microelements in young teeth hard tissues by the use of an X-ray microanalyser.

Determination of quantity, distribution and topography of calcium, phosphorus, magnesium and copper in transverse and longitudinal sections of deciduous and early erupted permanent human teeth were made by the use of an x-ray microanalyser and simultaneous analysis of the microstructure of the examined surface by the use of an electron scanning microscope. The examinations demonstrated the higher content of calcium and phosphorus, greater density and more homogenous distribution of these elements in the deciduous teeth. In the permanent teeth characteristic conglomerations of mineral granules were visible in the area corresponding to the dentine tubuli.

Calcium↗
PubMed1980

Total rate imaging with x-rays (TRIX)--a simple method of forming a non-projection x-ray image in the SEM using an energy dispersive detector and its application to biological specimens.

X-ray images can be formed in a conventional scanning electron microscope equipped with a Si(Li) energy dispersive spectrometer. All the x-ray events generated in the electron beam scanning process are synchronously displayed in the same manner as for dot maps. The quasi-digital image formed using Total Rate Imaging with X-rays (TRIX) exhibits good gray scale contrast and is dependent on topography, orientation and atomic number. Although this latter dependence is complex, it has been found useful in locating several types of inclusions in lung tissue (silicosis), human alveolar macrophages and cigarette smoke condensate. This is because of the greater depth of penetration of x-rays than backscattered electrons (BSE) usually used for such localizations in a matrix, and the negligible sensitivity of the Si(Li) detector to x-rays from an organic biological matrix. The optimum procedure is to use a combination of TRIX and BSE to investigate such specimens.

Electron Probe Microanalysis↗
PubMed1993

[The mapping of the local content of water and dry matter by using ultrathin frozen sections].

The possibility and applications of quantitative dry mass and water content mapping using an image analysis of darkfield intensity digitalization were shown on ultrathin freeze-dried cryosections. The distribution map obtained may be further used both for direct measurements of local dry mass and water content under physiological state and pathological disorders and for calculation of the concentration values obtained by quantitative X-ray mapping on freeze-dried cryosections in terms of millimoles per litre of cellular water.

Analog-Digital Conversion↗
PubMed1993

Surface analysis of four dental implant systems.

Dental implants obtained from four suppliers were analyzed by electron spectroscopy for chemical analysis and scanning electron microscopy. Three of the implants were delivered in a sterilized condition, while the fourth implant was delivered in a plasma-sprayed condition. The covering oxide layer consisted mainly of TiO2. Divalent and trivalent states of titanium were also detected, showing that TiO and Ti2O3 layers occurred. The thickness of the oxide formed on the plasma-sprayed implant was 3.4 nm. The oxide thicknesses of the sterilized implants were 4.6 +/- 0.4 nm. The surfaces of all samples were covered with organic contaminants. A strong fluorine signal was obtained from one sample, indicating that the supplier etches the implants in hydrofluoric acid. Calcium and zinc were found on the surfaces of all samples from one supplier, while calcium and silicon were found on the surfaces of the implants from another supplier. It is suggested that inorganic contaminants should be avoided because these species can possibly provoke the dissolution of titanium.

Calcium↗
PubMed1995

A new scanning electron microscopy approach to the quantification of bone mineral distribution: backscattered electron image grey-levels correlated to calcium K alpha-line intensities.

The introduction of backscattered electron (BSE) imaging in scanning electron microscopy (SEM) has led to new possibilities for the evaluation of mineral distributions in bone on a microscopic level. The different grey-levels seen in the BSE-images can be used as a measure for the local mineral content of bone. In order to calibrate these BSE-grey-levels (BSE-GL) and correlate them to mineral contents, various attempts, using reference samples with known weighted mean atomic number and/or using simulated bone tissues with known hydroxyapatite concentrations, have been made. In contrast, a new approach is presented here based on measurements of the X-ray intensities of the calcium K alpha-line on selected areas of real bone samples; the measured intensities are then related to the corresponding BSE-GL. A linear positive correlation between weight percent (wt%) calcium and BSE-GL was found. When the BSE-mode is standardized using carbon and aluminum as references, the different mineral contents in bone samples can be recorded as BSE-GL, calibrated to wt% of calcium or hydroxyapatite (HA), respectively. The resulting mineral concentration histograms have a dynamic range from 0 to 89 wt% HA and have a binwidth resolution of 0.45 wt% HA. The presented modifications of the BSE method strongly enhance its feasibility in the field of bone research and its application as a special diagnostic tool for bone diseases.

Bone Density↗
PubMed1996

Analytical microscopy and environment. Current developments using bioindicators of pollution by stable and radioactive elements.

Ecotoxicological investigations were performed on three sets of bioindicators. The first one concerns marine pollution of invertebrates (molluscs: the mussel Mytilus edulis and related species, crustaceans: the crab Liocarcinus puber and related species), contaminated by stable or radioactive elements originating from wastes discharged into sea water. The second one concerns freshwater pollution of vertebrates (fish: the brown trout Salmo trutta fario), contaminated by aluminium dissolved in rivers, as a consequence of an atmospheric pollution by acid rain. The third one concerns the atmospheric pollution of trees by plutonium (Casuarina equisetifolia). Mechanisms involved in the uptake, storage and elimination processes of these toxicants were studied, with a special emphasis on cellular and subcellular aspects of concentration sites. Two microanalytical methods were employed: Secondary Ion Mass Spectrometry (SIMS), using the ion microscope and the ion microprobe, and X-ray spectrometry using the electron microprobe (EMP). In marine organisms, the target organs and tissues of bioaccumulation of stable and radioactive elements (238U, 239Pu and 241Am), were shown to be mainly digestive gland, gill and exoskeleton. The target organelles were shown to be spherocrystals and lysosomes. Amoebocytes, enzymatically equipped with lysosomal phosphatase, were involved in the phagocytic clearance of metal pollutants. In trout, insolubilisation of Al phosphate within lysosomes and a high metal concentration within bones were observed. The tree Casuarina equisetifolia exhibits a particular ability to concentrate atmospheric plutonium within its leaves.

Air Pollution↗
PubMed1996

["Carious" and "noncarious" lesions of the hard dental tissues. Ultrastructural (SEM) and microanalytical (EDS) analyses of teeth from the 3rd century B.C].

The study was carried out on 80 teeth (70 of permanent dentition and 10 of primary one) of mandibular and maxillary bones. The teeth owned to subjects lived in the III c.b.C. in Sicily, and they were found in Naxos necropolis. The teeth were examined as far as carious and non carious lesions, then they were prepared for instrumental analyses by Scanning Electron Microscopy (SEM) and Energy dispersed X ray spectrometry (EDS). To an objective examination of the sample no caries were detected in the teeth sample apart one tooth, on the other hand there was an extensive occlusal abrasion, from a macroscopic point of view there were no difference as far teeth morphology. SEM examination pointed out all around dentinal tubules a circle of sclerotic dentin as reaction to occlusal wear. The amelocemental junction showed from a ultramicroscopic point of view an overlap of cementum onto enamel. EDS analysis pointed out a higher P concentration on the crown versus the root in all the teeth of the sample.

Dental Caries↗
PubMed1995

Scanning and electron microprobe analysis of metal-porcelain interface.

The purpose of this study was to analyze the interfacial region between porcelain and base metal alloy using scanning electron microscope with electron microprobe analyzer. Results gave evidence of formation of Nio and Cr2O3 with evidence of more migration of NiO towards the porcelain. Sandblasting of oxidized and fired metal samples (simulating firing of porcelain without its application) showed appearance of crystalline structure of Ni and Cragain, indicating delamination of oxide layer by sandblasting. At porcelain side analysis showed NiO and Cr2O3 and iron oxide plus Si, K, CI, Sn and Cu.

Dental Casting Technique↗
PubMed1998

Osteogenesis of electrically stimulated bone cells mediated in part by calcium ions.

Culture selected and expanded osteoblastic cells may be able to be reintroduced into massive skeletal defects to accelerate cell mediated regeneration of skeletal tissues, especially in bone ingrowth in total joint replacement, fracture healing, and osteoporosis. In vitro osteogenic cell culture is a useful model in studying the mechanism of bone metabolism under direct current stimulation. In this study, an osteoblastlike cell line was isolated from newborn rat calvaria. The osteogenic processes of the in vitro cultured cell line were studied by cytochemical, electron microscopic, and energy dispersive x-ray analysis techniques that resembled those observed in membrane bone ossification centers in vivo. Direct current stimulation of 100 microA/cm2 accelerated greatly the proliferation and calcification of the in vitro cultured cells. Intracellular free calcium ion metabolism was measured with an Adherent Cell Analysis and Sorting Machine. Under direct current stimulation, intracellular free calcium ion concentration increased an average of 2.3 times of the original level, which may play a key role in regulating osteogenesis and bone metabolism.

Alkaline Phosphatase↗
PubMed1986

Asbestos fibres in bronchoalveolar lavage fluid from asbestos workers: examination by electron microscopy.

The uncoated and coated fibre load in bronchoalveolar lavage (BAL) fluid was assessed using light microscopy, scanning electron microscopy, and x ray microanalysis in 15 subjects with previous, unprotected exposure to asbestos, including three with clinical and radiological evidence of asbestosis, and in 13 urban dwelling control subjects with no known occupational exposure to asbestos. The mean ferruginous body count per ml BAL fluid in asbestos exposed subjects as determined by light microscopy was 52 (range 0-333). No ferruginous bodies were detected in control subjects. The mean fibre count per ml BAL fluid in asbestos exposed subjects as determined by electron microscopy was 793 (133-3700), significantly greater than 239 (44-544) in controls (p less than 0.05). Electron microscopic counts correlated with duration of previous exposure to asbestos (r = 0.47, p less than 0.05) and with percentage neutrophil counts (r = 0.53, p less than 0.025). There was no relation between electron microscopic fibre counts and light microscopic ferruginous body counts. In 11 asbestos exposed cases x ray microanalysis confirmed the presence of asbestos and in six the asbestos fibre type was clearly identified. Of five subjects showing no asbestos bodies by light microscopy, all showed fibres by electron microscopy, and in three cases the presence of asbestos was confirmed by microanalysis. Among control subjects, fibres were either large organic fibres or smaller particles which microanalysis showed were not asbestos. In only one control case were a few fibres identified which were confirmed as asbestos fibres on microanalysis. Electron microscopic examination of BAL fluid may confirm past exposure to asbestos and probably gives a crude quantitative estimate of asbestos load.

Adult↗
PubMed2002

X-ray microanalytical studies of mineral localization in the needles of white pine (Pinus strobus L.).

Eastern white pine (Pinus strobus L.) shoots from mature trees were collected from two sites of contrasting soil pH: the Glendon campus of York University in Toronto, Ontario (pH 6.7 at 40 cm); and Muskoka near Huntsville, Ontario (pH 4.2 at 40 cm). Needles of ages 1-3 years were removed from the shoots, and the percentage of ash and silica was determined for all ages. Other needles were frozen in liquid nitrogen and kept in a cryo-biological storage system before x-ray microanalysis. Percentages of ash and silica were higher in the needles from Muskoka. Ash and silica increased with needle age for trees from the Muskoka site, but less so at the Toronto site. Of the 13 elements (Na, Mg, Al, Si, P, S, Cl, K, Ca, Mn, Fe, Cu and Zn) detected by microanalysis, Mn, Fe, Cu and Zn were detected in small amounts in the epidermis, endodermis and transfusion tissue (the layer of tracheids and parenchyma immediately surrounding the vascular bundles), and K, P, S and Cl were almost ubiquitous in distribution. Sodium was occasionally detected in the transfusion tissue, and magnesium was concentrated in the endodermal cells. The epidermal walls, transfusion tissue and endodermis were major sites of calcium localization. Silicon was concentrated in the extreme tips of the needles in all tissues, but particularly in the transfusion tissue, and more so in the Muskoka samples. Microanalysis revealed a higher Al content in the Muskoka needles, that Al was concentrated in the needle tips and that the transfusion tissues were major sites of accumulation.

Aluminum↗
PubMed2003

A sulphur matrix complex, elastic fibril composed of a fine core of amorphous elastin and microfibrils was largely accumulated in the aortic intima of aged rats.

We examined elastic fibrils in the aortic intima of aged rats with elastin staining, elastase digestion and X-ray microanalysis. The innermost elastic lamina, heavily stained by a brief treatment with azure II-toluidine blue without heating, was thin and fragmented, and an amorphous substance that stained weakly to moderately was accumulated in the thick subendothelial space of 26-28-month-old rat aortas. The substance was always present in the intimas; to a large extent in the aged rats but rarely in 5-month-old rats, and disappeared after digestion with elastase. The amorphous substance was identified as elastic fibrils approximately 0.1-0.2 microm in diameter under an electron microscope with tannic acid-uranyl acetate/lead citrate staining. Elastase digestion revealed that elastic fibrils were composed of a number of microfibrils, which were 10-12 nm in diameter, in and around a fine core of amorphous elastin. X-ray microanalysis revealed a clear peak of sulphur in the elastic fibrils.

Age Factors↗