Effect of estrogen on cell proliferation in colonic mucosa of the mouse

The effect of estrogen on cell proliferation in the descending colon of the mouse as an example of a non-target organ was investigated. Ovariectomized mice were given single or multiple injections of 10 ng/g body weight of 17 beta-estradiol and were killed 1 h after 3H-thymidine injection. Estrogen treatments decreased incorporation of 3H-thymidine into the DNA of colonic mucosa most markedly at 4 h after the single or the last of multiple injections. The inhibitory effect of estrogen on 3H-thymidine incorporation was greater and lasted longer after a single injection than after multiple ones. A similar inhibitory effect was observed in the colonic mucosa of male mice as well as in the mucosa of mice in which colonic epithelial cell proliferation was enhanced by refeeding after 48 h of fasting. However, the colonic mucosa of mice treated with estrogen implants for up to 4 days was not affected. Estrogen treatments caused no significant change in the DNA, RNA and protein contents of the colonic mucosa. The efficacy of estrogen treatments was verified by an increase in both the wet and dry weights of the uterine horns of ovariectomized mice.     

Shining a light on cell signaling in leukemia through proteomics: relevance for the clinic

Introduction: Although cure rates for acute leukemia have steadily improved over the past decades, leukemia remains a deadly disease. Enhanced risk stratification and new therapies are needed to improve outcome. Extensive genetic analyses have identified many mutations that contribute to the development of leukemia. However, most mutations occur infrequently and most gene alterations have been difficult to target. Most patients have more than one driver mutation in combination with secondary mutations, that result in a leukemic transformation via the alteration of proteins. The proteomics of acute leukemia could more directly identify proteins to facilitate risk stratification, predict chemoresistance and aid selection of therapy.

Areas covered: This review discusses aberrantly expressed proteins identified by mass spectrometry and reverse phase protein arrays and their relationship to survival. In addition, we will discuss proteins in the context of functionally related protein groups.

Expert commentary: Proteomics is a powerful tool to analyze protein abundance and functional alterations simultaneously for large numbers of patients. In the forthcoming years, validation of tools to quickly assess protein levels to enable routine rapid profiling of proteins with differential abundance and functional activation may be used as adjuncts to aid in therapy selection and to provide additional prognostic insights.     

Isolation of a bunyamwera group arbovirus from a naturally infected caribou

A Bunyamwera group arbovirus was isolated from the blood and from the brain of a female caribou parasitized with meningeal worms. The virus passed through a 0.45 micron filter; was ether sensitive; possessed no hemagglutination properties; could be propagated in suckling mice, 6-day old chick embryos, and BHK-21 tissue culture; and produced plaques in chick embryo fibroblast tissue culture. Neither complement-fixation or neutralization tests were sensitive enough to determine the serotype of the virus.