Urogastrone-epidermal growth factor is trophic to the intestinal epithelium of parenterally fed rats

The weight of the stomach, small intestine and colon and the mucosal crypt cell production rate of these tissues were significantly decreased after 10 days on an isocaloric TPN diet when compared to orally fed controls. Continuous infusion of recombinant beta urogastrone, at a dose below that needed to inhibit gastric acid secretion, largely prevented this decrease in crypt cell production rate and gastrointestinal tissue weights.     

Transmission of chromosomal instability after plutonium alpha-particle irradiation.

When investigating the biological effects of ionizing radiation on the haemopoietic system, a confounding problem lies in possible differences between the biological effects of sparsely ionizing, low linear energy transfer radiation such as X-, beta- or gamma-rays, and densely ionizing, high linear energy transfer radiation such as alpha-particles. To address this problem we have developed novel techniques for studying haemopoietic cells irradiated with environmentally relevant doses of alpha-particles from a plutonium-238 source. Using a clonogenic culture system, cytogenetic aberrations in individual colonies of haemopoietic cells derived from irradiated stem cells have been studied. Exposure to alpha-particles (but not X-rays) produced a high frequency of non-clonal aberrations in the clonal descendants, compatible with alpha-emitters inducing lesions in stem cells that result in the transmission of chromosomal instability to their progeny. Such unexpected instability may have important implications for radiation leukaemogenesis.     

Metabolism of carbazole

Zusammenfassung Es wurde mit Hilfe der Papier- und Dünnschichtchromatographie und der Isotopen-Verdünnungstechnik des C¹⁴-markierten Materials gezeigt, dass diein vivo-Hydroxylierung von Carbazol sowohl im Ratten- als auch im Kaninchenorganismus am Ort der höchsten Elektronenstauung stattfindet und zur Bildung von 3-Hydroxycarbazol führt.

---

---

This work was supported by a Burroughs Wellcome (Aust.) Research Fellowship (S.R.J.).