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PubMed1998

Nickel and gold in skin lesions of pierced earlobes with contact dermatitis. A study using scanning electron microscopy and x-ray microanalysis.

Cases of contact dermatitis due to nickel and gold especially in pierced earlobes, are increasing in number the world over. However, the presence of these metal fragments has not been demonstrated in the skin lesions. The aim of this study was to demonstrate nickel and gold in contact dermatitis lesions in pierced earlobes. Skin specimens taken from such earlobe lesions were examined using scanning electron microscopy and x-ray microanalysis. The pierced earrings worn when the lesions appeared were examined by the same techniques, and their analysis confirmed. In nickel dermatitis, small, electron-dense fragments were seen in the specimens examined by scanning electron microscopy, and nickel was detected in locations corresponding to these fragments by x-ray microanalysis. In contact dermatitis due to gold, small dense fragments containing gold were observed. It is suggested that small fragments of nickel and gold remain in the skin lesions of pierced earlobes for a long time, even after the studs have been removed, and cause prolonged irritation and various cutaneous reactions.

Adult↗
PubMed1998

Cytobiological studies on hemocyanin metabolism in the branchial heart complex of the common cuttlefish Sepia officinalis (Cephalopoda, Dibranchiata).

The present study confirms previous investigations that demonstrated a high copper content in the branchial heart and its appendage, and that gave the first indication that this organ complex might be involved in hemocyanin metabolism in Sepia officinalis L. Immunocytochemical localization of hemocyanin molecules within the endocytotic lysosomal system of the ovoid cells and tracer experiments with 125I-labeled Sepia hemocyanin suggest its endocytotic uptake. Energy-dispersive X-ray microanalysis and histochemical methods reveal a high copper content within the ovoid cells of the branchial heart. In view of the turnover of the respiratory pigment in the branchial heart of Sepia officinalis L., we believe that the ovoid cells are a site of hemocyanin catabolism.

Animals↗
PubMedDate not supplied

Morphologic features of chronic hepatitis associated with primary sclerosing cholangitis and chronic ulcerative colitis.

Histologic, ultrastructural, chemical, and statistical methods were used to study liver biopsy and autopsy specimens from 43 patients who had primary sclerosing cholangitis (PSC), with or without chronic ulcerative colitis (CUC), and from 19 patients who had CUC without PSC. In all study groups, essentially the same abnormalities were found in the hepatic parenchyma outside the major bile ducts, although nondiagnostic tissue samples were observed also. Specimens from patients with extrahepatic PSC were indistinguishable from those patients with combined extra- and intrahepatic PSC. Common findings included periductal fibrosis and inflammation, portal edema and fibrosis, focal proliferation of bile ducts and ductules, focal bile duct obliteration and loss of bile ducts, copper deposition, and cholestasis. Proliferation of bile ducts in some portal tracts and obliteration or absence of bile duct in others were the most characteristic changes. In most specimens, inflammatory changes appeared mild, yet biliary cirrhosis had developed in 34% of the patients. Specimens from patients with PSC, with or without CUC, more often contained bile and strikingly increased stainable copper (Grades 2 and 3) than did specimens from patients with CUC without PSC. Hepatic copper contents, measured by atomic absorption spectrophotometry, also were higher in specimens from patients with PSC. Study of PCS specimens by transmission electron microscopy and by energy-dispersive X-ray microanalysis revealed that most copper was sequestered in lipolysosomes. The recognition of strikingly similar morphologic features in many liver specimens from patients with either PSC or CUC or both suggests that the causes of these conditions are closely related.

Cholangitis↗
PubMedDate not supplied

Intracellular distribution of calcium in smooth muscle: facts and artifacts. A correlation of cytochemical, biochemical and X-ray microanalytical findings.

Cytochemical methods, based on the use of oxalate and pyroantimonate as Ca markers, show Ca accumulation in the sarcoplasmic reticulum (SR), mitochondria and nuclei of smooth muscle cells from the guinea-pig taenia coli. A good correlation was found between the Ca concentrations measured in subcellular components in situ by X-ray microanalysis and the endogenous Ca concentrations estimated in subcellular fractions by atomic absorption spectrophotometry. Our findings suggest that the in situ Ca concentrations (mmol/kg dry weight) are: about 100 in the SR and mitochondria, and about 60 inside the nucleus, significantly higher than in cytoplasm.

Animals↗
PubMed1983

Mass determination of thin biological specimens using backscattered electrons. Application in quantitative X-ray microanalysis on an automated STEM system.

The capabilities of modern computerized X-ray analysis systems can be expanded to the acquisition of various signals available in the electron probe microanalyzer, in parallel with the X-rays. These facilities allow the use of backscattered electrons for the measurement of the total specimen mass thickness, which can be used in mass fraction calculations, up to a (biological) specimen thickness of 10 micron. A mass measurement procedure based on the use of backscattered electrons may become an alternative for the X-ray continuum normalization method, often used in electron probe X-ray microanalysis. A mass measurement procedure using backscattered electrons is described, and preliminary results are given.

Animals↗
PubMed1984

Tumoral calcinosis: light and electron microscopic study with electron diffraction and x-ray microanalysis of the mineral deposit.

Samples of deposits taken from sites close to articulations in a young black African suffering from tumoral calcinosis with hyperphosphoraemia were studied by light and electron microscopy techniques. Light microscopy demonstrated lesions of a foreign body granuloma type in contact with calcium salt deposits suggesting that the process was of an active nature. Electron microscopy, and the demonstration of acid phosphatase activity, led to the identification of two cell types: mono or multinuclear macrophage type cells which phagocytose the deposit, and fibroblastic type cells. No signs of damage to the microvessels or the interstitial collagen were noted which could serve as a basis or a physiopathological explanation of the deposition. The deposits were analysed by energy dispersive X-ray microanalysis and by electron diffraction and were considered to be hydroxyapatite.

Acid Phosphatase↗
PubMed1992

[The effect of elevated environmental temperature on the development of a potassium deficiency in the body].

Electron microscopy and roentgen microanalysis were used to study the ultrastructure and electrolytic balance of K+, Na+ and Cl- of the animal myocardial tissue during general body hyperthermia. It was established that long-term effect of heating microclimate causes a distinct reduction of K+ in the cardiomyocytes accompanied by essential changes of the ultrastructure of ischemic character.

Animals↗
PubMed1983

Calcium detection in secretion granules of avian oviduct by scanning electron microscopy (SEM) and energy-dispersive X-ray microanalysis (EDX).

Secretion granules in the shell gland, isthmus, and albumin-secreting region of the hen oviduct were analyzed with WET-scanning electron microscopy (SEM) and EDX, a combination of wide-angle backscattered electron detector (BED) and energy-dispersive X-ray microanalyzer (EDX). Glutaraldehyde-fixed but unhydrated, unstained, and uncoated samples were analyzed; Ca was localized in all secretion granules in all three sections of the hen oviduct studied.

Animals↗
PubMed2000

A new method for detecting and localizing cell markers endocytosed by fibroblasts in epoxy resin semi-thin sections using scanning electron microscopy combined with energy dispersive X-ray microanalysis after ion-etching.

Cell marking is widely used to examine cell development and differentiation in developmental biology. We developed a new method for localizing cell markers in a semi-thin epoxy section with scanning electron microscopy. Cultured fibroblasts ingesting carbon particles were autologously transplanted into a rabbit transparent ear chamber, 6 mm in diameter and 100 microm in depth. Eight days after the transplantation, tissues in the chamber were fixed and embedded in epoxy resin. Semi-thin sections were cut and stained with toluidine blue. Fibroblasts in connective tissues which contained black spots were observed with a light microscope. These sections were subsequently ion-etched with an ion-coater and coated with platinum. The same fibroblasts were then visualized by secondary electron imaging using a scanning electron microscope. A nucleus with nuclear envelope, nuclear pores, a nucleolus and heterochromatin, mitochondria with cristae and rough endoplasmic reticulum were observed in the fibroblasts. The black spots in the fibroblasts were identified as bright bodies with the scanning electron microscope. The bright bodies were found to be a lump of tiny particles less than 100 nm in diameter. In order to analyse such particles with energy dispersive X-ray microanalysis, ion-etched sections were coated with carbon. X-ray energy spectrometry clearly demonstrated that these were carbon particles, which had been endocytosed by the fibroblast. This suggests that scanning electron microscopy combined with energy dispersive X-ray microanalysis is useful for detecting carbon particles in the cytoplasm at an ultrastructural level in semi-thin epoxy sections subsequent to ion etching and that this method may be applicable to other cell markers, such as gold particles to track cells in the field of cell development and cell differentiation.

Animals↗
PubMed1978

An x-ray microanalysis study of differences in concentration of elements in brain cells due to opiates, cell type, and subcellular location.

Adult female Sprague Dawley rats were divided into three groups and given two daily doses of: 1) morphine (25 mg/kg at each injection), or 2) methadone (5 mg/kg), or 3) saline for nine days. Two hours before the rats were killed on day 10, they were given a double dose of the drugs. Fifteen minutes before being killed, some of the morphine-treated rats were given the opiate antagonist naloxone (2.5 mg/kg), which caused a sudden arousal in these rats. At the time of killing, the preoptic-hypothalamic region was repidly removed and frozen in liquid propane to prevent translocation of elements in cells. Frozen 4-micrometer sections were cut, freeze-dried, and electron-probed in a scanning electron microscope, and energy-dispersive x-ray spectra were collected. The characteristic peak-to-continuum ratio for all detectable elements was determined in both the nucleus and the cytoplasm of ependymal cells and neurons. The data from nine cells of each type in each rat brain were then subjected to one- and three-way analysis of variance. The results show significant differences in the distribution of elements (sodium, magnesium, phosphorus, sulfur, chlorine, potassium, and calcium) which are dependent upon: 1) subcellular localization, 2) cell type, and particularly, 3) opiate treatment. The behavioral state produced by the opiates is correlated with the effects they have on intracellular concentration of several elements, most notably, sodium.

Animals↗
PubMed1995

Calcium-containing, smooth-surfaced endoplasmic reticulum and vacuoles in cells of the blastopore-forming region during gastrulation of the newt, Cynops pyrrhogaster.

Ultrastructural changes in cells of the blastopore-forming region (BFR) were examined during gastrulation of the newt, Cynops pyrrhogaster. Smooth-surfaced endoplasmic reticulum (sER), tubular in shape and with two types of vacuole, empty vacuoles and multilamellar vacuoles, appeared in cells of the BFR at the beginning of formation of the blastopore. The extent of the tubular sER increased during formation of the blastopore. With the deepening of the blastoporal groove, the tubular sER and multilamellar vacuoles disappeared in cells of the BFR. The empty vacuoles increased in number and appeared throughout the cytoplasm of the cells in the BFR and the marginal zone as formation of the archenteron progressed. Many large empty vacuoles were closely associated with deformed lipid droplets. Cytochemistry and X-ray microanalysis revealed the accumulation of calcium in the tubular sER and in some of the empty vacuoles. These results suggest important roles for the calcium-containing tubular sER in the regulation of the intracellular concentration of calcium during formation of the blastopore, as well as a role for empty vacuoles in the dissolution and consumption of lipid droplets during early gastrulation.

Animals↗
PubMed1985

Structure of a radiate pseudocolony associated with an intrauterine contraceptive device.

Transmission electron microscopy of a radiate pseudocolony associated with an intrauterine contraceptive device (IUCD) showed central bundles of extracellular fibers averaging 35 nm in diameter, surrounded by layered mantles of electron-dense, amorphous granular material. No bacterial, viral, or fungal structures were present. X-ray microanalysis revealed copper, sulfur, chloride, iron, and phosphorus; no calcium was found. It is postulated that these structures and histologically identical non-IUCD-associated granules from the female genital tract, as well as similar structures from other body locations, including those reported in colloid cysts of the third ventricle, are of lipofuscin origin.

Electron Probe Microanalysis↗
PubMed1985

Calcification of non-collagenous matrix in human gingiva: a light and electron microscopic study.

Tissue samples obtained from human gingiva with soft tissue calcification were processed for light and transmission electron microscopy. The stroma in these specimens revealed numerous foci of calcification in a matrix that consisted of closely packed branching microfibrils, 12 nm in diameter and a maximum of 2.5 micron in length. Calcospherites, 0.25-1.11 micron in diameter, were present within the matrix. They were constructed of needle-like units shown by high resolution electron microscopy and energy dispersive X-ray microanalysis to be apatite. Larger calcified masses were composed of calcospherites which were fused together. Matrix vesicles or other forms of membraneous material could not be found. The relationship between the mineral and non-collagenous microfibrils may suggest a role for the latter in the onset of calcification in this ectopic site.

Amelogenesis Imperfecta↗
PubMed1992

Experimental calcification in rat submandibular gland.

The present study describes the phenomenon of calciphylaxis, rapid calcification due to treatment with sensitizer dihydrotachysterol (DHT) and challenging agent 5-hydroxytryptamine (5-HT) in the rat submandibular gland (SMG) in terms of light and electron microscopy, and histochemistry. For biophysical analysis of the calcified bodies, X-ray microanalysis (XMA) and X-ray powdered diffraction methods were used. The calcified lesions in the salivary glands were histologically divided into 3 types: type 1, calcification of basal membranes in duct-like structures; type 2, granular calcified materials with remarkable necrotic changes in cell, containing 3 kinds of small vesicular structures observed in electron microscopy; and type 3, von Kossa's positive structures containing needle-like crystalline and electron-dense amorphous materials. Con A and UEA-1 lectin staining reactions were strong in the type 1 and 2 lesions. These findings suggest that the calcification matrix may contain mannose, fucose and glucose. The X-ray microanalysis of calcified materials revealed the magnesium whitelockite pattern, the type 3 displayed high quantities of Ca, P, and Mg ions comparing with the type 1 and 2, and the X-ray diffraction showed the hydroxyapatite pattern. We suggest that the above changes may be categorized as dystrophic calcification due to necrotic alterations brought about by the hypercalcaemic condition.

Animals↗
PubMed1997

Cadmium removal by a new strain of Pseudomonas aeruginosa in aerobic culture.

A fluorescent pseudomonad (strain CW-96-1) isolated from a deep-sea vent sample grew at 30 degrees C under aerobic conditions in an artificial seawater medium and tolerated cadmium concentrations up to 5 mM. After 140 h, strain CW-96-1 removed > 99% of the cadmium from solution. Energy dispersive microanalysis revealed that the cadmium was removed by precipitation on the cell wall; sulfide production was confirmed by growth on Kligler's agar. Based on 16S ribosomal DNA sequencing and fatty acid analysis, the microorganism is closely related to Pseudomonas aeruginosa.

Aerobiosis↗
PubMed1991

X-ray microanalysis of cerium in mouse spleen cells demonstrating acid phosphatase activity using high voltage electron microscope.

An X-ray microanalytical study was carried out on mouse spleen cells demonstrating acid phosphatase (AcP-A) activity, using cerium (Ce) as the capture agent at different accelerating voltages. The enzyme reaction products were localized in the lysosomes and appeared dense and homogeneous. The presence of cerium was confirmed by X-ray microanalysis. The main spectral line of cerium was present at La = 4.84 keV. The result showed that the X-ray count of Ce and the background (B) decreased significantly with increasing accelerating voltage between 100 and 400 kV. The change was more pronounced between 100 and 200 kV and thereafter, minimal change was noted. Consequently, the computed P/B ratio increased appreciably with increasing accelerating voltage. Thus, significant P/B ratio in X-ray microanalysis of biological specimens could be achieved by using a medium voltage transmission analytical electron microscope at accelerating voltage between 300 and 400 kV.

Acid Phosphatase↗

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