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PubMed1992

X-ray microanalysis of bulk hydrated specimens of neoplastic and non-neoplastic human urothelium.

Specimens of neoplastic and non-neoplastic human urothelium were rapidly frozen against a copper block immersed in liquid nitrogen, planed in a cryoultramicrotome and then examined by low-temperature scanning electron microscopy (LTSEM) following coating by aluminium. Energy dispersive X-ray microanalysis (XRMA) was performed on the superficial urothelial cells and on gelatin blocks mounted in parallel which had known concentrations of sodium, potassium, chloride, and phosphorus. The neoplastic urothelial cells had significantly less phosphorus (P less than 0.05) than non-neoplastic cells and the ratios K+/P,K+/Na+, and K+/Cl- were significantly higher in neoplastic cells than in non-neoplastic cells (P less than 0.00001). These results are consistent with those expected in cells with a sustained increase in intracellular pH caused by stimulation of Na+/H+ ion membrane exchange.

Electrolytes↗
PubMedDate not supplied

Crystalloid structures in retroperitoneal paragangliomas: a light and electron microscopic study.

Samples from three clinically functional retroperitoneal paragangliomas were studied by light and electron microscopy. The tumors exhibited a Zellballen pattern histologically, and ultrastructurally all three neoplasms consisted of cells containing catecholamine granules. Prominent cytoplasmic crystalloids were present in all cases. The crystalloids were identified in routine histologic sections, demonstrated eosinophilia, and stained with periodic acid-Schiff, Giemsa, phloxine-tartrazine, and azan stains. Ultrastructurally the crystalloids were osmiophilic, often appeared as slender needles, were membrane bound, and demonstrated a periodicity of 9 nm. The crystalloids, unlike the catecholamine granules, were negative for catecholamine fluorescence. X-ray microanalysis, however, revealed the selective presence of chromium in both catecholamine granules and crystalloids.

Adult↗
PubMed1985

X-ray microanalytic method for measurement of dry matter and elemental content of individual bacteria.

A method for the determination of dry matter and elemental content of individual bacterial cells is described. The method is based on energy-dispersive X-ray microanalysis in a transmission electron microscope. A theory for area correction of intensity is developed. Escherichia coli in the late exponential phase of growth and early stationary phase (glucose limited) had an average dry matter content of 278 and 154 fg/cell, respectively. Of the elements detected, sodium, magnesium, phosphorus, sulphur, chlorine, potassium, and calcium together made up 15 to 17% of the dry matter content. A phosphorus content of 4.2 to 5.4% of the dry matter was found in these cells. Volume measurements of air-dried cells gave an average of 1.20 to 1.25 micron3. These results emphasize that dry matter content and elemental composition can be measured directly on single cells from complex microbial communities.

Electron Probe Microanalysis↗
PubMed1989

Pigment resembling atmospheric dust in Peyer's patches.

Terminal ileal pigmentation was observed during colonoscopy, in surgically resected specimens, and autopsy cases. Microscopically, black pigment was seen within macrophages in the lamina propria and submucosa, closely related to the Peyer's patches. Three ilia from autopsies with no macroscopic pigmentation showed deposits following digestion and X-ray microanalysis. X-ray microanalysis of tissue sections and digestates revealed a heterogenous population of particles. Approximately one third of the particles contained calcium and phosphorus and were considered endogenous. The rest of the particles were predominantly aluminum and magnesium-rich silicates, which were considered exogenous. Analysis of particulate extracted from lungs and ilea of four autopsy cases demonstrated remarkable similarities in composition. These findings suggest that the ileal deposits are derived from atmospheric dust. This pigment is believed to migrate into the Peyer's patches through the M cells of the follicle associated epithelium, although other mechanisms for pigment deposition cannot be ruled out.

Dust↗
PubMed2005

Evidence of the involvement of plant ligno-cellulosic structure in the sequestration of Pb: an X-ray spectroscopy-based analysis.

European walnut (Juglans regia) plants were grown in pots, on peat soil contaminated with lead (Pb), for four years. European walnut was chosen because it grows in Mediterranean climates, it yields a high biomass, and a fine quality wood. In the above ground parts Pb concentration was 1000 times lower than in roots: in 50 g roots there was 450 mg of Pb. Microanalysis of roots found in periderm more than 50% of the total root Pb. Pb L(III) EXAFS spectroscopy was performed on: root powder from Pb-exposed plants, Pb-impregnated cellulose and lignin. Comparison of plant material with lignin and cellulose helped to envisage a plant disposal strategy for Pb. This may consist in establishing links with large organic molecules, which are abundant constituents of cell walls. EXAFS spectroscopy evidenced the presence of Pb-O bindings within the ligno-cellulosic structure in roots. Lead was scantly conveyed to the shoots, giving to walnut plants an added asset in Pb phytostabilization.

Calcium↗
PubMed1982

High resolution microanalysis for phosphorus in Golgi complex beads of insect fat body tissue by electron spectroscopic imaging.

Golgi complex beads are 10 nm particles arranged in rings on the smooth forming face of the Golgi complex that stain specifically with bismuth in arthropod cells. In vitro experiments with biological molecules spotted on to cellulose acetate strips indicated that bismuth bound to the beads through phosphate groups. We could detect a weak phosphorus signal from the beads using a new technique called electron spectroscopic imaging that is capable of very high spatial resolution (0.3-0.5 nm) and sensitivity (50 atoms of phosphorus). Detection was not obscured by tissue staining with bismuth or uranyl acetate of by using an inorganic buffer (Na cacodylate). Localization of phosphorus was greatly improved by using colour-enhanced computer pictures of the electron spectroscopic images and quantitating the images. The results indicate that the phosphorus content of the beads is large enough to account for their bismuth reactivity.

Adipose Tissue↗
PubMedDate not supplied

Non-calcified breast particles: a possible new marker of breast cancer.

Malignant and benign human breast tissue containing radiographic evidence of calcifications were studied by means of scanning electron microscopy and x-ray microanalysis. In addition to the well-known calcium-phosphorus deposits, discrete particles containing calcium with little or no phosphorus and calcium in combination with other elements were found. Moreover, particles containing elements other than calcium were observed. These include Al, Fe, Mg, Si, Cu, Zn, Cr, Ti, Ni, Pb, Au, Ag, Mo, Cl, I. Some of these "noncalcifications" contained a single element, others a combination of elements. These findings differ from the view that all breast particles are calcifications. Further study could lead to the development of new diagnostic techniques for the detection of breast cancer and/or chemotherapeutic agents.

Breast Neoplasms↗
PubMed1993

Chemical nature and distribution of calcium compounds in radiolucent gallstones.

A high failure rate for radiolucent cholesterol gallstones to dissolve with oral bile acids may be due to the presence of insoluble calcium compounds. Twenty sets of radiolucent gallstones, 7-20 mm in diameter, obtained from 20 patients undergoing cholecystectomy, were cut, and the outer surface, outer rim, middle portion, and central core areas were scanned for calcium by energy-dispersive X-ray microanalysis (EDX) and scanning electron microscopy (SEM). Scrapings from the four areas of each stone were analysed by infrared spectroscopy. A sample of the crushed stone was used for chemical estimation of cholesterol. Eleven (55%) of the 20 cholesterol (84-96% dry weight of cholesterol) stones showed presence of calcium by EDX; the distribution was peripheral in 5, homogeneous in 4, and central in 2. The chemical compound was calcium bilirubinate in 10 and calcium carbonate in 8 stones. Calcium compounds are present in a high proportion of radiolucent gallstones considered suitable for chemodissolution by conventional criteria. Their unrecognized presence may explain the high failure rate of such stones to respond to medical therapy.

Adult↗
PubMed1997

Tape stripping of human stratum corneum yields cell layers that originate from various depths because of furrows in the skin.

Tape stripping of human stratum corneum is widely used as a method for studying the kinetics and penetration depth of drugs. Several factors can influence the quantity of stratum corneum that is removed by a piece of tape, such as the manner of tape stripping, the hydration of the skin, cohesion between cells, body site and interindividual differences. However, few data are available about the influence of furrows in the human epidermis on the tape-stripping technique. In this study, we investigated the efficacy of tape stripping in removing complete cell layers from the superficial part of the human stratum corneum. A histological section of skin that was tape-stripped 20 times clearly showed nonstripped skin in the furrows, indicating persistent incomplete tape stripping. Replicas of tape-stripped skin surface demonstrated that even after removing 40 tape strips the furrows were still present. We validated the tape-stripping method further with X-ray microanalysis in the mapping mode by scanning electron microscopy, using a TiO2-containing compound as a marker. TiO2 applied to the skin before the tape-stripping procedures was still present after the tenth tape strip, and was specifically located on the rims of the furrows. We emphasize that results from studies using the tape-stripping method have to be viewed from the perspective that cells on one tape strip of the stratum corneum may be derived from different layers, depending on the position of the tape strip in relation to the slope of the furrow, and such results should be interpreted with considerable caution.

Adhesives↗
PubMed1989

The lack of age-pigments and the alterations in intracellular monovalent electrolytes in spontaneously hypertensive, stroke-prone (SHRsp) rats as revealed by electron microscopy and X-ray microanalysis.

Male, spontaneously hypertensive, stroke-prone (SHRsp) rats established by Okamoto et al. (1974) were studied. About 80% of the males of this strain have a particularly short life span (33-41 weeks); they display a considerable hypertension (above 220 mmHg) and a tendency for plurifocal brain strokes. Hypertension and strokes can be provoked in an accelerated and synchronized fashion by supplementing 1% NaCl into their drinking water. Symptoms of the appearance of brain strokes can be judged from characteristic signs of motor disorders, and can be established also by pathohistology. Since hypertension and arteriosclerosis are frequently involved in aging, the question we intended to answer was whether these animals may represent a model of the normal aging process or not. Two approaches are described: (1) Accumulation of lipofuscin granules in their brain, liver and myocardium was followed by transmission electron microscopy before and after the appearance of strokes. It has been established that these tissues do not show any typical accumulation of lipofuscin granules, although submicroscopic signs of an enhanced damage of cell organelles (especially of mitochondria in liver and brain cells, but not in myocardium) were encountered. (2) The intracellular monovalent composition in the brain and liver was measured by using bulk-specimen X-ray microanalysis. The intracellular Na-content (mEq/kg water) was significantly higher (170-200%) in both the brain and liver cells, whereas the K-content increased only moderately (118-130%). The results suggest that although the SHRsp rats do not represent a direct model for the normal aging process from the point of view of lipofuscin accumulation, the shifts of the monovalent electrolyte contents in the brain and liver cells observed already in the youngest ages, are similar to those observed in aged normal rats. The theoretical consequences of such a conclusion are discussed.

Aging↗
PubMed1985

The application of physico-chemical procedures in the analysis of urinary calculi.

All physico-chemical techniques used in the analysis of urinary calculi have inherent advantages and limitations. Although x-ray powder diffraction can identify constituents unambiguously, certain minor components can be missed. Infrared spectroscopy is more sensitive but band assignment at low concentrations is difficult. Scanning electron microscopy together with energy dispersive x-ray analysis permits the simultaneous investigation of morphology and chemical microstructure. However, microanalysis of elements lighter than sodium is not possible and constituents are prone to irradiation damage. With the electron microprobe, minor constituents can be detected but tedious sample preparation procedures are required. Transmission electron microscopy is extremely useful in determining constituent inter-relationships and ultrastructure but ultramicrotomy is very difficult. Thermal gravimetric analysis gives quantitative information easily but does not satisfactorily distinguish between struvite and brushite. In an attempt to assess the accuracy of chemical analyses, 62 calculi were investigated applying several chemical tests. Those for Mg2+, PO4(3-), NH4+ and uric acid proved highly reliable while that for Ca2+ often yielded an incorrect result. The test for oxalate was totally unsatisfactory. Investigators of stone composition and structure should include x-ray diffraction (or infrared spectroscopy) and scanning electron microscopy as their methods of first choice. In addition, chemical or thermogravimetric analyses should be utilized in an auxiliary capacity.

Chemistry, Physical↗
PubMed2000

Elemental changes in skin from patients with basal cell carcinoma.

Intracellular ionic shifts have been described in connection with normal and abnormal cell proliferation. This study was conducted to determine the elemental composition of a cell tumor classified as basal cell carcinoma in skin. The biopsies were taken from 10 patients. Control biopsies were taken from the non-affected skin from the same patients. Cryosections were cut and attached to carbon specimen holders. After freeze drying the sections were analyzed by X-ray microanalysis in a scanning microscope. The X-ray microanalytical results showed that the content of magnesium, phosphorus and potassium was significantly higher in the cancer cells than in the control cells (p < 0.05). The content of sodium, chlorine, calcium and sulfur was similar in both affected and unaffected cells. We conclude from these data that basal cell carcinoma has a characteristic elemental composition. It is possible that increased potassium and magnesium levels have a stimulatory effect on this tumor type, in contrast to other types of cancer cells where elevated sodium and chlorine and lowered potassium levels have frequently been found.

Adult↗
PubMed1997

X-ray microanalysis of black piedra.

The elements present in the fungal structures produced by Piedraia hortae in vivo and in vitro have been investigated using electron microscopy X-ray microanalysis. Phosphorus, sulphur and calcium were detected in the nodules which developed on hair and on colonies on culture. These elements belong to the extracellular material that compacts the pseudoparenchymatous organization of the fungus. They may be present due to the capacity of melanin-like pigments to sequester ions and/or they may form part of the sulphates and phosphates of the polyanionic mucopolysaccharides that constitute the extracellular material. Environmental contaminants such as aluminium, silicon and iron were detected exclusively on the surface of the nodule. They were deposited or linked to the residual molecules produced during the breakdown of the cuticular keratin. The advantages of these techniques for elucidating the chemical nature of fungal structures are discussed.

Ascomycota↗
PubMed1996

Distinct immuno-localization of mucin and other biliary proteins in human cholesterol gallstones.

BACKGROUND/AIMS: Cholesterol gallstones consist of cholesterol crystals and smaller amounts of pigments and calcium salts, arrayed on a mucin plus protein matrix. The localization of the various biliary proteins in the stones has not been characterized. We aimed to localize several biliary proteins in gallstones in order to determine their possible role in stone formation and growth. METHODS: The distribution of several matrix proteins and their relationships to the minerals were determined using immunostaining and EDAX microanalysis on hemisected cholesterol gallstones. RESULTS: Pigment areas were rich in calcium and contained Cu, P and S. These elements were absent in cholesterol regions. Mucin was identified in a three-dimensional network intercalated between cholesterol crystals and as septa between deposits of pigments and cholesterol; APF/CBP and ApN coated only the pigment deposits. No specific topographical localization was found for albumin or IgA. CONCLUSIONS: This suggests a role for mucin, APF/ CBP and ApN in the formation of cholesterol gallstones. We propose that cholesterol crystals bind directly to mucin, whereas calcium salts and pigments deposit on APF/CBP and ApN bind to the mucin.

Bile↗
PubMed1988

Elemental levels in mast cell granules differ in sections from normal and diabetic rats: an X-ray microanalysis study.

Mast cells around the thymus of rats stain red with alcian blue and safranin indicating that the mast cells are probably of the peritoneal (connective tissue) type. After the onset of streptozotocin induced diabetes some cells contain both red and blue granules and blue staining cells may appear. X-ray microanalysis of frozen freeze-dried sections from diabetic male CSE Wistar rats showed electron dense granules to have similar amounts of S to normal rat mast cell granules but reduced levels of Na, Mg, P, Cl and K. Two cells also had electron lucent granules with very high levels of Na, Cl, K and Ca and reduced concentrations of S. The differences in elemental composition suggest that the mast cells from diabetic rats are not immature, but are related to the condition of induced diabetes, and that granules of very different composition can occur within a single cell. X-ray microanalysis has given an insight into mast cell granule elemental content which was not possible by conventional biochemical methods.

Animals↗
PubMed1984

Calcium redistribution, calcification and stone formation in the parotid gland during experimental stimulation and hypercalcaemia. Cytochemical and X-ray microanalytical investigations.

Distribution and redistribution of intra- and pericellular calcium was investigated in the parotid gland of rats under secretory stimulation and hypercalcaemia. The effects of hypercalcaemia and secretory stimulation and of the combination of both were compared. Calcium content was determined by atomic absorption spectrometry. Calcium distribution within the tissue was demonstrated by light microscopical ( GBHA ) staining and electron microscopical (pyroantimonate method) cytochemistry in combination with X-ray microanalysis. Typical calcium depot sites were the basal and cellular membranes, the calcium buffer organelles (i.e. mitochondria) the secretory granules and the acinar lumina. After stimulation (by isoprenalin ) a decrease of calcium-enriched secretory granules and a depletion of intracellular calcium buffer organelles occurred. During hypercalcaemia (induced by dihydrotachysterol), a calcium overloading of the cell membrane and intracellular buffer organelles without calcification was observed. Combined stimulation and hypercalcaemia induced an excessive calcium overloading of all intra- and extracellular calcium depots with excessive calcium release into the acinar lumina resulting in calcium phosphate aggregates and stone formation. Secretory stimulation and simultaneous hypercalcaemia exert potentiating effects on intracellular and intraluminal calcification proposing an importance for pathogenesis of human sialolithiasis.

Animals↗