A deoxynucleoside triphosphate triphosphohydrolase promotes cell cycle progression in .

Intracellular pools of deoxynucleoside triphosphates (dNTPs) are strictly maintained throughout the cell cycle to ensure accurate and efficient DNA replication. DNA synthesis requires an abundance of dNTPs, but elevated dNTP concentrations in nonreplicating cells delay entry into S phase. Enzymes known as deoxyguanosine triphosphate triphosphohydrolases (Dgts) hydrolyze dNTPs into deoxynucleosides and triphosphates, and we propose that Dgts restrict dNTP concentrations to promote the G1 to S phase transition.

Principles and Procedures for Assessment of Acute Toxicity Incorporating Methods.

Acute models are being used to support an increasing number of application areas including (1) product research and development, (2) product approval and registration as well as (3) the transport, storage and handling of chemicals. The adoption of such models is being hindered, in part, because of a lack of guidance describing how to perform and document an analysis. To address this issue, a framework for an acute toxicity hazard assessment is proposed.

Evaluation of the predictivity of Acute Oral Toxicity (AOT) structure-activity relationship models.

Several public efforts are aimed at discovering patterns or classifiers in the high-dimensional bioactivity space that predict tissue, organ or whole animal toxicological endpoints. The current study sought to assess and compare the predictions of the Globally Harmonized System (GHS) categories and Dangerous Goods (DG) classifications based on Lethal Dose (LD50) from several available tools (ACD/Labs, Leadscope, T.E.