With the use of a conditional 3-MA mouse knockout mouse model, we demonstrate that NF-Ya deletion creates an accumulation of HSCs in G(2)/M and prompts apoptosis, causing hematopoietic failure and death of the animal. These defects are accompanied by the dysregulation of multiple genes that influence cell cycle control (cyclin b1 and p21), apoptosis (Bcl-2), and self-renewal (HoxB4, Notch1, Bmi-1) and are independent of p53. Our results identify NF-Y as a pivotal upstream participant in a regulatory network necessary for the preservation of cycling HSCs. (Blood.
2012; 119(6): 1380-1389)”
“Invited international experts participated in a 2-day workshop organized by the European Society of Toxicologic Pathology (ESTP) to evaluate and discuss spontaneous and induced laryngeal lesions in rodents. The main
purpose of the workshop was to agree upon the terminology and relevance of a range of laryngeal changes that varied from very subtle epithelial alterations up to severe metaplastic or neoplastic lesions. The workshop experts concluded that minimal, focal epithelial changes of the laryngeal epithelium, predominantly occurring at the base of the epiglottis, should be given the descriptive term of “epithelial alteration” and Birinapant manufacturer assessed as “non-adverse”. Although observed as induced effects they may also occur in non-treated animals and were not considered to have a potential for a laryngeal dysfunction. Also, cases of minimal to slight laryngeal squamous metaplasia that are not observed diffusely could occur spontaneously or as
treatment-induced lesions and should be assessed as “non-adverse”. 17DMAG Cytoskeletal Signaling inhibitor Cases of moderate to severe laryngeal squamous metaplasia observed diffusely in multiple levels should be regarded as “adverse”, as there is a potential for dysfunction of the larynx. The occurrence of dysplasia or cellular atypia linked to laryngeal squamous metaplasia should always be reported separately and described in detail. In the evaluation of treatment-related effects of the larynx in studies utilizing aged animals, it has to be considered that moderate or even severe cases of focal laryngeal squamous metaplasia may occasionally be found as age-related, spontaneous lesions. Although inhalation exposure of rodents to non-genotoxic compounds may cause laryngeal squamous metaplasia, none of the workshop experts were aware of any reported cases of tumor induction in the larynx with a non-genotoxic compound. Therefore, for non-genotoxic compounds, the workshop experts did not regard laryngeal squamous metaplasia by itself as a precancerous lesion. (C) 2009 Elsevier GmbH. All rights reserved.”
“Acetoacetate decarboxylase (AADase) has long been cited as the prototypical example of the marked shifts in the pK(a) values of ionizable groups that can occur in an enzyme active site. In 1966, it was hypothesized that in AADase the origin of the large pK(a) perturbation (-4.