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Biomedical subjects

A H Verbueken

Publications and source records attributed to A H Verbueken.

14 recordsLinked to original sources
PubMed1992

Laser microprobe mass spectrometric identification of cyclosporin-induced intrarenal microliths in rat.

Using laser microprobe mass analysis (LAMMA), the composition of 'micro-calcifications (dystrophic type)' or 'metastatic calcifications', previously described in rats given high doses of cyclosporin, have been identified. Female Wistar rats given 12.5, 25 or 50 mg kg-1 per day of cyclosporin in olive oil by gastric gavage developed intrarenal calcifications detected by silver nitrate staining (von Kossa) in the outer medulla after two weeks. The calcifications stained red with periodic acid-Schiff reagent and appeared to be intraluminal microliths with concentric laminations. They could be identified by LAMMA as calcium phosphate (hydroxyapatite), indistinguishable from undecalcified bone. These studies indicate that intraluminal obstruction by calcium phosphate microliths, similar to that seen with magnesium depletion or high phosphate diets, may contribute to renal damage in rats given high-dose cyclosporin. LAMMA appears to be an appropriate technique for identifying both the elemental and organic moieities of intrarenal calcium deposits.

Administration, Oral↗
PubMed1987

Applications of laser microprobe mass analysis in medicine.

An instrument for laser microprobe mass analysis (LAMMA) has been available for applied research for several years. The value of this sensitive microanalytical technique has been demonstrated in various fields of science, including medicine and biology. The LAMMA instrument comprises two laser systems. The first is a weak continuous pilot laser that can be aimed at a region of interest of the sample, e.g., a histological microtome section, using a light microscope. The second is a powerful pulsed laser that can evaporate the selected area. The generated ions are then analyzed in a time-of-flight mass spectrometer. The advantages of LAMMA present new perspectives in biomedical research. Elements can be located and analyzed down to the parts per million-level with a 1 micron spatial resolution. Speciation and/or fingerprinting of (in)organic molecules may be obtained. However, the technique is destructive, the quality of the light-microscopic view is poor, and quantification is still under investigation. In this review, the analytical characteristics of LAMMA are evaluated, including instrumental features, detection sensitivity, ionization parameters, molecular speciation, and quantification. Applications of LAMMA in medicine are reviewed, covering the microanalysis of a wide range of physiological and toxic constituents (alkali metals, calcium, aluminum, titanium, fluorine and iodine, heavy metals, transition elements, and molecular compounds).

Humans↗
PubMed1986

Laser microprobe mass analysis (LAMMA) to verify the aluminon staining of bone.

Triammonium aurin tricarboxylate (aluminon) has been used to localize aluminum in 2 micron sections of undecalcified, methyl methacrylate embedded bone obtained from patients with terminal chronic renal failure. Aluminum appeared in four cases as bright red lines at the mineralized-bone boundary. In two cases, however, purplish lines were found and one patient showed red as well as purplish lines. Laser microprobe mass analysis (LAMMA) identified aluminum at the location of the red lines and both aluminum and iron at the purplish lines. Furthermore, both iron and aluminum were found in histiocytic bone marrow cells, which showed brownish aluminon staining. It appears that when aluminum and iron occur together, aluminon staining may yield aberrant results. This study shows that LAMMA can be used for the identification of elements sought by histochemical methods and thus permits the evaluation of their staining effects.

Aluminum↗
PubMed1985

Laser microprobe mass analysis: a review of applications in the life sciences.

The characteristics and analytical utility of laser microprobe mass analysis (LAMMA) are described and evaluated, and a short history of this recent microanalytical technique is presented. A review of the areas of application of LAMMA and related laser microprobes is presented with special emphasis on applications in the life sciences.

Aerosols↗
PubMed1985

Microanalysis in biology and medicine: ultrastructural localization of aluminum.

Four methods for the ultrastructural tracing of elements in man and animal are discussed. In addition to histochemical staining, emphasis was put on three innovative sophisticated microanalytical techniques: electron probe X-ray microanalysis, secondary ion mass spectrometry, and laser microprobe mass analysis. The principles and merits of these methods for microanalysis are reviewed. The application of these techniques for the detection of aluminum at the microscopic level is described in detail because of the clinical importance of this metal in severe chronic renal failure. A literature survey concerning the microanalysis of aluminum in biology and medicine is presented.

Aluminum↗
PubMed1984

Laser microprobe mass spectrometry of platinum in dog kidney after cisplatin administration.

By means of laser microprobe mass analysis ( LAMMA ) platinum was detected in the renal proximal tubular cells of a dog that had been intravenously administered the antitumor drug cisplatin (5 mg per kg body weight). No definite subcellular localization of the heavy metal was obtained. Sample preparation and analytical features are examined to increase spatial resolution of analysis while maintaining sufficient detection efficiency. The LAMMA method is destructive, but the amount and type of evaporated material can readily be determined when using LAMMA in combination with transmission electron microscopy. Instrumental optimization and standardization of mass signals is possible by using platinum-loaded, ion-chelating resin beads embedded and sectioned with the tissue.

Animals↗
PubMed1984

Ultrastructural localization of aluminum in patients with dialysis-associated osteomalacia.

Using laser microprobe mass analysis, we studied the ultrastructural localization of aluminum in liver and bone tissue of chronic-hemodialysis patients with proven aluminum-induced osteomalacia. In the liver, aluminum was observed to be almost exclusively associated with iron. Detectable aluminum and large amounts of iron were found in lysosomes of both hepatocytes and Kupffer cells. In bone, aluminum was localized at the osteoid/calcified-bone interface and also was associated with iron in some cases.

Adult↗