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Biomedical subjects

B Gylseth

Publications and source records attributed to B Gylseth.

33 records · Page 2Linked to original sources
PubMed1982

Analysis of fibres in human lung tissue.

Standard UICC crocidolite fibres and fibres extracted from occupationally exposed human lung tissue have been analysed by scanninng electron microscopy after different preparation procedures. A significant fibre loss has been shown due to the adhesion of fibres to the breakers. Fibres are also discarded during the washing and extraction of the lung tissue samples. The recovery was found to be 30 to 40% both for UICC standard specimens and for lung tissue samples.

Asbestos↗
PubMed1981

Amphibole fibers in a taconite mine and in the lungs of the miners.

Fibers of the amphibole mineral series have been demonstrated in the dust from an open taconite ore mine. Though the total dust levels in some places are high, exposures to fibers are below one fiber/cc. The energy dispersive X-ray spectra of the amphibole fibers correspond to those of cummingtonite-grunerite, hornblende, or actinolite. The same type and size distribution of fibers were found during post mortem analyses of lung tissue from two previously exposed miners. The pathological examination revealed an undifferentiated small cell carcinoma of left lung as well as pulmonary fibrosis in one of the cases. In the second case a poorly differentiated squamous cell carcinoma of left lung was found along with silicosis.

Asbestos↗
PubMed1981

Talc dust pneumoconiosis.

Various types of mineral dust can induce interstitial pulmonary fibrosis, but there is no definite correlation between lung X-ray findings, tissue lesions and the type of dust. In this paper, we report on the post mortem verification of talcosis by lung tissue analysis, using light microscopy, scanning electron microscopy, energy dispersive x-ray microanalysis and x-ray diffractometry.

Aged↗
PubMed1981

Inorganic fibers in lung tissue from patients with pleural plaques or malignant mesothelioma.

The concentration of inorganic fibers in the lungs of patients with malignant mesothelioma and pleural plaques has been compared to that of patients without cancer or chronic respiratory diseases. The fiber concentrations have been determined by scanning electron microscopy and given as number of fibers per gram of dried tissue. A statistically significant difference in inorganic fiber content was found between the different groups.

Adult↗
PubMed1981

Analysis of inorganic fiber concentrations in biological samples by scanning electron microscopy.

Analyzing fibers with electron microscopic techniques involves several preparation steps, especially during the analysis of fibers in human tissue. The influence of these steps on the analytical result was studied in detail. Fiber number was unaffected by the mild sonication of fiber suspensions analyzed with scanning electron microscopy. Significant fiber losses appeared during the filtration of fiber suspensions through 0.8-micrometer pore-size Nuclepore membranes. Shrinkage of the tissue during dry ashing broke lung fibers and consequently increased the fiber concentration and affected the fiber length distribution. Dry ashing, however, removed more of the organic debris than wet ashing; thus specimens prepared with dry ashing were more suitable for scanning electron microscopic analysis. A fairy good correlation was demonstrated for the analysis of fibers with scanning and transmission electron microscopy.

Asbestos↗
PubMed1981

Massive pulmonary deposition of rutile after titanium dioxide exposure: Light-microscopical and physico-analytical methods in pigment identification.

Autopsy findings in a 55-year old man known to have been occupationally heavily exposed to titanium dioxide dust showed extensive pulmonary deposition of white pigment. By energy dispersive X-ray analysis (EDAX) and electron and X-ray diffraction, the pigment was identified as rutile. By ordinary transmitted light microscopy, deposits of the white crystalline titanium-dioxide could not be distinguished from anthracotic pigment present in the lung sections. By transmitted polarized and incident light microscopy, the different nature of the two types of pigment was immediately evident. Absence of inflammatory and fibrotic changes in the lungs in our case lends support to the view that rutile is biochemically inert.

Environmental Exposure↗
PubMed1980

Scanning electron microscopy and x-ray microanalysis of mineral deposits in lungs of a patient with pleural mesothelioma.

Scanning electron microscopy of lung tissue, ashed at low temperature, and obtained from an insulation worker who had died of pleural mesothelioma, showed the presence of numerous inorganic particles and fibres. A regional variation in fibre concentration in different tissue samples was found, and the size distribution of naked fibres and asbestos bodies was determined. By energy dispersive x-ray microanalysis the fibres were identified mainly as amphibole asbestos. This method also showed the presence of particles containing titanium and of fragments of diatom shells. Despite a mean concentration of 33 x 10(6) fibres per gram of dry tissue no significant lung fibrosis was found.

Adult↗
PubMed1979

Determination of inorganic fiber density in human lung tissue by scanning electron microscopy after low temperature ashing.

The concentration of asbestos fibers in lung tissue may give information about previous occupational asbestos exposure. A procedure for the preparation, quantification and identification of asbestos fibers in human tissue is presented in this report. The procedure is based on low-temperature plasma ashing of dry tissue, examination of the ash by scanning electron microscopy, and energy dispersive X-ray microanalysis. The advantages and disadvantages of this method are also discussed briefly.

Asbestos↗
PubMed1979

An exchange of membrane filter samples of airborne asbestos between one United Kingdom and three Scandinavian laboratories.

An asbestos fiber counting trial based on the postal exchange of mounted and unmounted membrane filter samples was conducted between laboratories in Denmark, Norway, Sweden and the United Kingdom. The exchange was organized on the same basis as a previous international exchange involving nine countries (5); the United Kingdom laboratory had also participated in the previous exchange. Differences in counting techniques were distinguished from those due to the method used to make the filter transparent. Counting techniques gave rise to the biggest differences, giving a ratio of highest to lowest count of 2.75 for amphibole and 3.2 for chrysotile asbestos slides. A comparison was also made with the results of the previous international trial; it was made possible by the recounting of some of the slides from this exchange. Serious deterioration over two years was found in all slides except those mounted with the acetone/triacetin method.

Air Pollutants↗
PubMed1978

Whole blood chromium level and chromium excretion in the rat after zinc chromate inhalation.

Studies on absorption and excretion of chromium in the rat exposed to known atmospheric concentrations of zinc chromate in an inhalation chamber and the influence of diurnal variations in physical activity have been carried out. Chromium analyses were performed on samples of blood, urine and faeces using a method for determining chromium in small samples of biological material based on flameless atomic absorption spectrometry. Zinc chromate is absorbed quickly during exposure and excreted mainly via urine. An accumulation of chromium in blood was observed, followed by a slow elimination. It is suggested that chromium from zinc chromate enters the blood in the hexavalent state.

Animals↗
PubMed1977

Evaluation of chromium exposure based on a simplified method for urinary chromium determination.

The urine chromium levels for unexposed and chromium exposed persons were determined by a simplified method which is well suited for routine, large-scale use. A group of welders working on chromium alloyed steel were investigated. For these welders a high degree of correlation was found between the concentration of inhaled chromium and the chromium concentration in the urine immediately after work. At an exposure level of 0.05 mg/m3, measured as chromium, a urinary chromium concentration of approximately 40 microng/l was measured after work. This urinary chromium level is suggested as a guideline indicating the need for a thorough investigation of chromium exposure.

Air Pollutants↗