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A H Tulusan

Publications and source records attributed to A H Tulusan.

63 records · Page 4Linked to original sources

[Pulmonal silicone-embolism. Light microscopic, electron microscopic and enzymehistochemical investigations in the rabbit lung (author's transl)].

Artificial silicone-embolism in rabbits was produced by injection of Baysilon-antifoam into the ear vein. Electron microscopic and histochemical observations of the lung were made, concerning the toxicity and elimination of the embolic material. At 13 months after injection the embolic silicone was not significantly reduced in amount. The rabbit lung is unable to eliminate chemically inert silicone by enzymatic degestion. We noted serious defects of endothelial cells and pneumocytes, destruction of capillaries and local atelectases. These defects are preponderantly mechanical in origin, but may be caused by lack of substrate or energy in cells deprived of their blood supply. Atelectases are interpreted as a result of break-down in surfactant-synthesis.

Animals↗

Expression of oncogenes in human breast cancer specimens.

More than 60 breast cancer specimens were screened for their expression status of 25 different proto-oncogenes. The screening method is based on in vitro synthesis of a radioactive cDNA copied from the total cellular RNA of tumor tissue. This cDNA is hybridized to cloned oncogene probes which are immobilized to a GeneScreen membrane. Frequently multiple oncogenes were found expressed although expression levels were rather moderate. 25-30% of the analyzed tumors showed significant expression of either erbB, src, raf1, lck or H-ras. Although neu expression--an oncogene believed to be particular relevant as prognostic parameter for mamma carcinoma--was screened for most of the tumors with a heterologous gene probe, expression signals could be detected in about 20% cases. The only notable correlation with classical clinical parameters such as tumor size and proliferation stage, hormone receptor status and different DNA indices was the observation that tumors lacking the progesterone receptor frequently express multiple oncogenes. Advantages and limitations of the cDNA/dot-blot screening for oncogene expression are discussed.

Animals↗