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PubMed1988

Electron-microscopic and microprobe analyses on the pigmented and unpigmented enamel of Sorex (Insectivora).

Sorex belongs to the Insectivora and has a pigmented tooth enamel due to iron. The pigmented enamel (PE) has a mean Ca/P weight ratio, analyzed by quantitative electronprobe X-ray microanalysis, of about 1.9 (mean molar Ca/P ratio 1.46), and the unpigmented enamel (UE) a Ca/P weight ratio of about 2.0 (mean molar Ca/P ratio 1.59). The PE has a higher iron content (with a value of about 8%) than the UE, as shown by microanalysis of ultrathin sections. Laser microprobe mass analysis (LAMMA) has shown that the carbonate content in the UE is higher than in the PE. In the LAMMA spectrum of the negatively charged ions the carbonate lines could be compared directly with those of negatively charged iron ions. The pigmentation is associated with a low Ca/P ratio but may transfer mechanical strength and acid resistance strength to the PE.

Animals↗
PubMed1985

Effects of reserpine and isoproterenol on elemental distribution in submandibular gland of rat.

The effects of a single dose of reserpine or isoproterenol on the acinar cells of rat submandibular gland were investigated by electron microscopy and X-ray microanalysis. About 4 h after injection of reserpine, the cellular Ca concentration started to increase and at 24 h a level two to three times the control value was reached. The mucus content of the cells increased in parallel with the Ca concentrations. Isoproterenol stimulation depleted the acinar cells of their mucus. Resynthesis of mucus was visible at 8-12 h after injection. Changes in cellular Ca concentrations followed the mucus content of the cells. After 24 h both the mucus content and the Ca concentration were significantly increased over the control values. High-resolution X-ray microanalysis on thin cryosections showed that the calcium was accumulated in the mucus granules, both after reserpine and after isoproterenol administration. The newly synthesized mucus was also more calcium-rich than the original mucus. The effect of a single isoproterenol stimulation on elemental content of rat submandibular gland acinar cells was not significantly different from that of chronic isoproterenol treatment. Chronic treatment with reserpine resulted in a higher cellular Na/K ratio than a single dose.

Animals↗
PubMed1985

X-ray microanalysis of uremic nephrocalcinosis: cellular distribution of calcium, aluminium and silicon in uremic nephrocalcinosis.

Nephrocalcinosis with a deposition of aluminum and silicon has been previously reported in uremic rats. To clarify the origin of these elements thin sections of renal cortex were examined by means of electron microscopy and energy dispersive x-ray microanalysis. Studies were performed on subtotally nephrectomized rats (SNX) and sham-operated control animals. Electron microscopy of proximal tubular epithelial cells in SNX rats unlike control rats revealed severe mitochondrial disorganization; irregularity of the tubular basement membrane which exhibited various inclusions; and lamellar bodies within the brush border membrane. On x-ray microanalysis disorganized mitochondria contained calcium and silicon, while secondary lysosomes displayed aluminum and silicon. The tubular basement membrane of SNX rats, as well as lamellar body-like inclusions within the brush border contained calcium, aluminum and silicon together. It is suggested that lysosomal and mitochondrial interaction in proximal tubular cells of uremic rats may contribute to the deposition of calcium together with aluminum and silicon in the renal parenchyma, resulting in nephrocalcinosis.

Aluminum↗
PubMed1980

Biomedical microanalysis--putting it to work now in diagnostic pathology.

Based on a review of seven years' experience with microanalysis in human pathology, the emphasis of this keynote paper is that currently available microanalytic instrumentation and methodology are of great use diagnostically. The appropriate diagnostic questions which must be posed for microanalysis center around those seeking the cause of the disease (etiologic diagnosis). The preventive and forensic aspects of etiologic diagnosis are stressed. Pathologists analyse not only tissues but also material samples. The backscattered electron (BSE) image with compositional contrast has been essential in making efficient diagnostic use of microanalysis in the scanning electron microscope (SEM). From the 454 specimens seen in the four years 1976-1979, examples are presented to illustrate several aspects of microanalysis: e.g., documentation of the identity and source of toxic dust in lungs; identification of particulate materials in liver, kidney, salivary glands, lymph nodes, etc.; problems of contamination of specimens; use of high vs low magnification analysis; relative volume of tissue sampled using thick (5 micrometer) vs thin (100nm) sections; time required for analysis; and use of fresh frozen, cryo-sectioned tissue for analysis of soluble materials. For practical diagnostic microanalysis, SEM with BSE and x-ray microanalysis of 5 micrometer thick tissue sections at present seems to be the most efficient procedure.

Electron Probe Microanalysis↗
PubMed1981

A cooling chain for studies of cryofixed biological specimens by scanning transmission electron microscopy and X-ray microanalysis.

A cooling chain is described which enables the transfer of frozen hydrated biological specimens (ultrathin cryosections as well as about 1 micrometer thick cultured cells) from a cryoultramicrotome into a scanning transmission electron microscope with a field emission gun. Transfer is done at 118 K, specimen temperature in the microscope is 165 K. Sublimation processes are controlled visually and by mass spectrometry. Electron micrographs and X-ray microanalytical spectra of cryofixed unstained tissue culture cells and rat liver tissue sections are described and discussed. Contamination of the specimen is much reduced by use of the cold stage.

Animals↗
PubMed1979

X-ray microanalytical studies on native myofibrils and mitochondria isolated by microdissection from honey-bee flight muscle.

The distribution of elements was studied by means of energy dispersive X ray microanalysis in the honey-bee flight muscle. Semi-quantitative analysis of bulk muscle specimen, isolated mitochondria and isolated myofibrils either in resting or stretched state was performed. High K peak was observed in the spectra of bulk muscle specimen resembling the spectra of myofibrils and high P peak resembling the spectra of mitochondria. In the myofibrils no substantial difference was found between the spectra of A bands and Z lines, but they contained much higher K peak than the spectra of I bands.

Animals↗
PubMed1982

SEM and X-ray microanalysis of human prostatic calculi.

Calculi removed from human prostates affected with nodular hyperplasia were analyzed with scanning electron microscopy and EDAX system. The general spectrum was made up of Na, Al, Mg, S, P, Ca and Zn. Two types of stone were identified morphostructurally and microanalytically: calculi type I of nodular surface with high peaks of S, and calculi type II polyfaceted with high peaks of P and Ca. Their formation from corpora amylacea and/or exogenous constituents is discussed. The superficial deposit of Zn suggests its incorporation from the prostatic liquid and does not seem to play an important role in the genesis.

Calculi↗
PubMed1981

Preparation and assessment of frozen-hydrated sections of mammalian tissue for electron microscopy and X-ray microprobe analysis.

A system is described for preparing and examining frozen-hydrated sections of mammalian tissue, using commercially available equipment. An essential part of the system is a liquid nitrogen cooled vacuum transfer system. Minor modifications were required to interface the various manufacturers' equipment, and also to facilitate handling of specimens in the cryoultramicrotome. A variety of criteria indicates that our sections are truly frozen-hydrated, but negligible image contrast in the sections is a serious problem both for morphological work and X-ray microanalysis.

Animals↗
PubMedDate not supplied

X-ray microprobe analysis of the retina and RPE in sheep with ovine ceroid-lipofuscinosis.

Ovine ceroid-lipofuscinosis (OCL) is one animal model for the human condition, and because autofluorescent lipopigments are prominent in the brain and eye, it may also prove useful as a model for aging. For example, a progressive decline in electrical recording from brain and retina are observed in both aging and OCL. Samples of retinal and retinal pigment epithelial (RPE) tissues were obtained from a young control. 2 animals with OCL and a normal aged sheep. Specimens were cryo-fractured and examined by scanning electron microscopy/x-ray microanalysis. Measurements made of 6 individual cells in the ganglion layer of OCL specimens, the remainder of the retina, and RPE showed age-related changes in zinc, iron, and copper which were associated with lipopigment accumulation in the RPE. There was marked decrease in phosphate, sulfur, and manganese levels, as photoreceptor cells and their outer segments are lost in the disease process. This is the first report of metal analysis in the retina and RPE in a disease entity, and as a function of normal aging.

Aging↗
PubMed2004

Elemental composition of airway surface liquid in the pig determined by x-ray microanalysis.

The ionic composition of the airway surface liquid (ASL) is of importance in cystic fibrosis and exercise-induced asthma. However, literature data on the composition of the ASL vary markedly. The aim of the study was to determine the composition of the ASL, using two different methods involving minimal manipulation. In one method, the composition of the ASL was measured by X-ray microanalysis of frozen-hydrated samples. In the second method, small dextran beads were equilibrated with the ASL in a moisture chamber, isolated, dried, and analyzed. Plasma or serum from the same pigs was also analyzed. Both methods showed that the Na and Cl concentrations in the ASL are close to the concentrations of these ions in plasma. X-ray microanalysis of frozen-hydrated ASL showed significantly higher K, P, and S because here the upper layer (containing cell debris and secreted mucus) is sampled, whereas the bead method samples the watery component of the ASL. Ultrastructural analysis of the epithelium at various osmotic values showed evident damage at concentrations of 50 mM or less. These data support the notion that the physiologically important watery component of the pig ASL has an ionic composition close to that of plasma.

Animals↗
PubMed1996

Histomorphological and chemico-physical analyses of the mineral matrix of micropetrotic human bone.

Micropetrotic areas of human bone were analyzed with reference to their distance from blood vessels and to the age of the subjects. Undecalcified bone sections were treated with various solvent, soaking and etching substances to establish the nature of the material occluding the osteocytic canalicular cavities, and were examined by means of microradiographic and microdurimetric methods and X-ray microanalysis to evaluate the degree of mineralization in the bone matrix. Since it was only after strong etching with HCl that the canalicular network became visible under light and scanning electron microscopy, it is clear that the debris filling the canalicular network consists almost entirely of mineral substance. The degree of mineralization of micropetrotic bone is high because it is always a more mature type of bone, but the mineral content of the matrix and the Ca/P ratio do not differ significantly from those of neighbouring bone where the canalicular network is fully pervious.

Adult↗
PubMed1982

X-ray microanalysis in dermatology.

The current trends in X-ray microanalysis as applied to dermatology are described by reviewing papers which have made a significant contribution to the field. Under separate headings, the analysis of hair, nail and epidermis is reviewed with an emphasis on quantitative results. Our recent work on green hair has revealed a higher than normal copper content derived from copper-containing tap and pool water. In nail the sulfur content was shown to be evenly distributed throughout the nail plate and the calcium content to be too low to influence on the "hardness" of the nail. Our study of nails from cystic fibrosis patients showed that the Na, K, and C1 content increased, which is diagnostic for the disease, and that the Ca content could be used to monitor the preparation of nail samples for analysis. With the aid of X-ray microanalysis it has been possible for the first time to study the electrolyte composition of the different strata of epidermis by using freeze-fixed and freeze-dried cryosections. Only the basal stratum maintains a normal Na/K quotient and all cell layers above that one appear to have dysfunctional cell membranes, i.e. inadequate pumping of Na out of the cells. A subsequent study of the effects on normal epidermis by DNCB showed that after 6 hours post-treatment, abnormal Na, K and P levels appeared which differed from those seen in post-mortem changes of normal epidermis.

Copper↗
PubMed1998

The contribution of trace elements from smokeless powder to post firing residues.

The smokeless powders in 22 kinds of ammunitions seized from one of the Japanese gang groups were analyzed by scanning electron microscopy/energy dispersive X-ray microanalysis (SEM/EDX). Copper(Cu), sulfur(S), potassium(K), silicon(Si), aluminum(Al), calcium(Ca), iron(Fe), chlorine(Cl), and barium(Ba) were detected. Cu was found in all samples. One sample contained a high amount of Ba. One part of the burnt smokeless powder was found to contain Cu, K, Ca, Fe and S, the other part contained Cu, Fe, and zinc(Zn). It has been reported that the elements in gunshot residues originate from a bullet and/or a primer. However, this demonstrates that smokeless powder could be the source of some of the elements detected.

Aluminum↗
PubMed2002

[Does arteriosclerotic calcinosis of vessel walls imitate osteogenesis? Pathomorphological studies of arteriosclerotic plaque].

OBJECTIVE: For it is supposed that calcification of arteriosclerotic plaques imitates osteogenesis, it was studied whether the morphology of different stages of calcification supports such an assumption. MATERIAL AND METHODS: Investigations were performed on one operation specimen of a dissecting aneurysm of the aorta and five human autopsy aortas. From different arteriosclerotic plaques, paraffin sections without and after EDTA-decalcification were prepared. Light microscopic, scanning (SEM) and transmission electron microscopic (TEM) investigations as well as X-ray microanalysis were performed. RESULTS: By light microscopy, it became obvious that the intensity of calcification of arteriosclerotic plaques is not reflected by the conventional H&E stain--the real amount of calcium-phosphorus deposits becomes only evident by using a special stain, such as the alizarin red S reaction. In the SEM, arteriosclerotic plaques with granular calcification were characterized by accumulations of isolated calcified globules often reflecting the structure of necrotic cells. TEM exhibited even accumulations of calcified bodies corresponding to the shape of cells; cell remnants were present in the neighborhood. X-ray microanalysis of the granules detected calcium and phosphorus and a relative high content of magnesium, reflecting the composition of calcospherites in granular media calcification (71). By SEM, solid calcifications exhibited associations of calcified bodies resembling those of the isolated granules in early calcification but with one stuck onto the other. X-ray microanalysis revealed that these deposits are characterized by high amounts of calcium and phosphorus and a minor component of magnesium in comparison to the isolated granules. CONCLUSIONS: From the investigations it is concluded that calcification of arteriosclerotic plaques imitates the process of granular media calcification which is assumed as "dystrophic" calcification of fragments of necrotic cells. The hypothesis of a "regulated" calcification as it occurs in cartilage or bone cannot be supported for the development of the calcified plaques; however, it cannot be excluded that proteins that are associated with osteogenesis participate in the transition of calcification to ossification in the vessel wall.

Aortic Dissection↗
PubMed1984

X-ray microanalysis of the rat parotid gland after chronic sympathectomimetic stimulation.

The effects of chronic treatment with isoproterenol, reserpine, prenalterol, and terbutaline on rat parotid gland were investigated by electron microscopy and X-ray microanalysis. Chronic isoproterenol treatment induced lower potassium and calcium concentrations in the acinar cells. The cells were enlarged and contained more and larger zymogen granules than acinar cells in the controls. The zymogen granules contained markedly less sulfur, potassium, and calcium than in control animals. Prenalterol had effects similar to those of isoproterenol, but less pronounced, whereas terbutaline had no significant effects. Chronic treatment with reserpine caused a decrease in calcium levels but did not affect potassium levels. The changes in elemental composition in parotid acinar cells after chronic treatment with isoproterenol and reserpine differed from those induced by the same treatment in the submandibular gland of the rat.

Animals↗
PubMedDate not supplied

Extracellular compartments of the blowfly eye: ionic content and topology.

To analyze the elemental composition and topology of the extracellular compartments of the compound eye, the eyes of blowflies Calliphora vicina were rapidly frozen and ultrathin cryosections were freeze dried. Three zones of an ommatidium, peripheral cytosol of visual cells, rhabdomeres, and ommatidial cavities were analyzed by X-ray microprobe analysis. The ommatidial cavity was found to contain sodium and potassium in proportion similar to that in the blowfly hemolymph. Potassium-to-sodium ratio in a cytosol was typical for a cytosol. The rhabdomeres displayed an electrolyte content intermediate between the above compartments. Three topologically connected extracellular compartments were characterized by the experiments with tracers, monastral blue and lanthanum: (1) common intercellular space of ommatidia including peripheral clefts between the visual cells, both tracers entered this compartment; (2) the ommatidial cavity, which is not accessible for monastral blue, however, as revealed by our X-ray microanalysis, it was reachable for lanthanum; (3) rhabdomeric loops, which were accessible for lanthanum entering either via the cavity or from the common intercellular clefts. The above characteristics of the ionic content and topology of ommatidial compartments might suggest higher sodium and lower potassium content in the microvilli as compared with the cytosol. The rhabdomeric and "cavital" plasma membranes are assumed to be permeable for these ions so that a voltage of only 25-30 mV, negative inside, is probably formed across them, much lower than the known resting potential -60 mV across the peripheral plasma membrane of a visual cell.

Animals↗
PubMed1980

[Cutaneous argyria: an electron microscopic study of four eases with microanalysis X study of one case (author's transl)].

This study was done in order to follow the fate of silver in the dermis of chronic argyria. Silver was easily recognizable in the tissue as irregular aggregates of elementary granules round or ovoid in shape, ranging from 30 to 40 mm in size. The microanalysis X showed that the metal was bound with sulfur. In the cases of recent intoxication, the main location of silver was intracellular: the granules were found in the lysosomes as elementary particle or as dense heterogen bodies. In the cases where intoxication had been stopped a long time ago, silver was found either on fibrillar component of the connective tissue or in the basal material of sweat glands. The results show that silver is at first phagocytized by macrophages but this cell is unable to perform complete degradation of the silver salt or metal. Then silver is found on connective fibers where it remains on sulfated glycoproteins.

Aged↗
PubMed1984

Distribution of concanavalin A binding sites on normal human urinary bladder mucosa and bladder tumors by transmission and scanning electron microscopy and X-ray microanalysis.

We used concanavalin A (con A)-peroxidase-iron dextran-diaminobenzidine (DAB) technique for the electron microscopic detection of con A binding sites on cell membranes. Normal bladder mucosa showed a sparse distribution of con A binding sites with both transmission (TEM) and scanning (SEM) electron microscopy, but bladder tumors showed a higher concentration in the distribution of con A binding sites in proportion to the histopathological grade of transitional cell carcinoma. Quantitative estimation of the con A binding sites was attempted using scanning X-ray pulse analysis of iron elements contained in the reaction complexes. Con A binding sites were quantitatively the smallest in normal mucosa, increasing proportionate to the grade of the bladder tumor. Some specimens were compared by the ferritin-labelled method and the pattern of ferritin conjugates distribution was similar to that seen with the con A-peroxidase-iron dextran method.

Carcinoma, Transitional Cell↗