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Biomedical subjects

K Määttä

Publications and source records attributed to K Määttä.

13 recordsLinked to original sources
PubMed1998

Acid-catalyzed isomerization of fucosterol and delta5-avenasterol.

This work shows that fucosterol, delta5-avenasterol, and similar ethylidene-side chain sterols can undergo acid-catalyzed isomerization to give a mixture of five isomers. Four isomers formed from fucosterol were analyzed, using gas chromatography-mass spectrometry, and were characterized as delta5-avenasterol, two delta5,23-stigmastadienols, and delta5,24(25)-stigmastadienol. When the unsaponifiables fraction from oat oil was subjected to acid hydrolysis, the two delta5,23-stigmastadienol isomers and delta5,24(25)-stigmastadienol were detected while fucosterol coeluted with sitosterol. Interisomerization of ethylidene-side chain sterols represents a limitation to the use of the acid hydrolysis method in the determination of sterols in food and other plant materials rich in these sterols, e.g., oat lipids.

Anticholesteremic Agents↗
PubMed1982

Pulmonary berylliosis: report on a fatal case.

A fatal case of pulmonary berylliosis in a 59-year-old male is described. Three months after a heavy exposure to the dust of broken fluorescent light bulbs he developed severe respiratory distress with bilateral lower zone opacities on the chest radiograph. Histological examination of a lung biopsy revealed inflammatory changes with a granulomatous component and some necrosis. The diagnosis of berylliosis was confirmed by determination of beryllium in lung tissue by chemical analysis. Two years after the onset of symptoms the patient died of respiratory failure.

Acute Disease↗
PubMed1975

Pulmonary deposits of titanium dioxide in cytologic and lung biopsy specimens. Light and electron microscopic x-ray analysis.

Although titanium dioxide (TiO2) is widely used in industry, its biologic effects have not been determined. In the present investigation, open lung biopsy samples and sputum specimens from three former TiO2 factory workers and bronchial aspirations from seven TiO2 factory workers were analyzed by conventional and x-ray microanalytic light and electron microscopic methods. These studies showed that in the alveolar macrophages, lysosomes contained a significant amount of titanium as well as smaller amounts of silicon, aluminum, iron, and potassium. It appeared that titanium dioxide was situated in round or oval-shaped particles whereas silica or silicon compounds were localized in separate, more rectangular structures. There fore, the adverse effects may be induced by such quartz or silicon compounds. The latter are utilized as covering substances in the manufacture of TiO2 pigment.

Adult↗