The aim of the present work was to gain insight into a putative anticancer effect of dietary vitamin D3 (cholecalciferol) in a rat model of colon carcinogenesis. Male rats were assigned to three different dietary groups. The dietary regimens were based on a standard murine-defined diet (AIN-76A) or a stress diet containing 20% fat, reduced Ca2+ concentration, a high phosphorus-to-Ca2+ ratio, and either low or high vitamin D3 content. Colorectal cancer was induced by administration of the procarcinogen 1,2-dimethylhydrazine (DMH). Blood Ca2+, 1,25-dihydroxyvitamin D3 [1,25(OH)2D3], and 25-hydroxyvitamin D3 [25(OH)D3] levels were measured in DMH-treated rats and in respective weight- and age-matched dietary control groups. Colonic epithelial proliferation was assessed by determining thymidine kinase (TK) activity, bromodeoxyuridine (BrdUrd) incorporation into crypt cell DNA, and the mean labeling index along the colonic crypt continuum. Maintenance of rats on the stress diet either unmodified or supplemented with vitamin D3 in the absence of carcinogen treatment provoked a time-dependent rise in colonic TK activity and hyperproliferation of colonic epithelium. DMH treatment of rats maintained on the standard diet caused a marked increase in the proliferative indexes of colonic epithelium and in expansion of the crypt proliferative compartment. TK activity and the crypt mitotic zone were significantly augmented in the animal group fed the stress diet. Supplementary vitamin D3 abrogated the stress diet-enhanced colonic responses to the carcinogenic insult. Colon tumor multiplicity was fourfold higher in animals fed the stress diet than in animals maintained on a standard diet. The marked rise in colonic tumor multiplicity and adenocarcinoma incidence in rats fed the stress diet was obliterated by supplemental dietary vitamin D3. Cumulatively, the present results indicate that dietary vitamin D3 impedes the neoplastic process in murine large intestine and strengthen the view that inappropriate changes in dietary components and micronutrients are contributory determinants of colorectal cancer.
S.C. ( 1 ) Nemtzov, Sinai, Y. ( 1 ), Ben-Yosef, R. ( 1 ), Sharon, Y. ( 1 ), Kaplan, D. ( 1 ), Har-Zion, M. ( 1 ), Dolev, M. ( 1 ), Glasner, D. ( 2 ), Morgan, J. ( 2 ), ו Bojilov, K. ( 2 ). 2000.
“The Pygmy Cormorant (Phalacrocorax Pygmeus) In The Bet She’an Valley: Challenges For Conservation Of An Endangered Species.”. Israel Journal Of Zoology, 46, Pp. 168-169. .
Publisher's Version This volume comprises a report on excavation areas located outside the Canaanite-Israelite city wall of the City of David. First are stratigraphic reports of Areas B and D1, two of the four excavation areas located east of the city wall on the eastern slope of the City of David hill. They are followed by a report on pottery finds from the two areas and a discussion that focuses on the most significant aspect of the finds in all four areas, namely the existence of extramural quarters in part of the Israelite period (especially Stratum 12). This volume concentrates on finds from the major strata from the City of David, from the Iron Age. The material presented here will contribute to a clearer understanding of biblical Jerusalem, for which, despite the large number of excavations there, well-documented archaeological data are still rare.
This volume presents the inscribed finds and related material from all areas and strata of the City of David excavations. Chapters are devoted to Hebrew and Aramaic inscriptions, inscribed pottery, Hebrew bullae, bullae with figurative decoration, Lmlk seal impressions and concentric circles, a Hebrew seal and seal impressions, rosette-stamped handles, incised handles, and locally stamped handles and associated body fragments of the Persian and Hellenistic periods. Appendices are devoted to an Arabic ostracon and potsherds with incised South Arabian letters. A concordance to Volumes V–VI of the City of David reports (Qedem 40 and 41) concludes the volume.
The Ultimatum Bargaining paradigm is often thought of as a demonstration of extreme disagreement between experimental evidence and game theoretical predictions and the basic assumption of rationality from which they are derived. Using the data of four experiments on Ultimatum Bargaining which I am involved in, I argue that, quite differently from this general impression, rationality in the sense of self-interested motives, is very much present in the observed behavior of both proposers and responders in the Ultimatum Bargaining game. Part of the argument calls for a broader interpretation of the notion of rationality than just immediate money maximization and the backward induction argument.
Apoptosis is a physiological process of cell death that occurs in all multicellular organisms. Its dysregulation has been postulated as one of the main causes in the development of diseases such as cancer, AIDS, autoimmune diseases and allergy. Apoptosis has been mainly studied in the inflammatory cells that participate in the late and chronic stages of allergy (eosinophils, neutrophils, lymphocytes and macrophages) as a new way to elucidate the pathogenesis of this disease. Nevertheless, much less it is known about the regulation of apoptosis in the "initiators" of the allergic process: The Mast Cells. In normal conditions, mast cells are described as long-living cells that keep a constant number of cells in tissues. However, increased numbers of mast cells are observed in the late phase of asthma and in both the inflammatory and in the repair/remodeling stage of various inflammatory/fibrotic disorders. In this report, we discuss the possible mechanisms that regulate the apoptotic process in normal conditions and disease, such as survival factors and death receptors. A link between mast cell activation, during the early stages of the allergic process, and triggering of antiapoptotic signaling pathways is also suggested as an important contributor to the extended life of mast cells.
We consider repeated games where at any period each player knows only his set of actions and the stream of payoffs that he has received in the past. He knows neither his own payoff function, nor the characteristics of the other players (how many there are, their strategies and payoffs). In this context, we present an adaptive procedure for play - called "modified-regret- matching" - which is interpretable as a stimulus-response or reinforcement procedure, and which has the property that any limit point of the empirical distribution of play is a correlated equilibrium of the stage game.
