Abstract: One aspect of the invention generally relates to use of tissue enriched miRNAs as biomarker to estimate tissue damage in a fluid sample. In a second aspect, methods are provided for monitoring a subject who is exposed or might have been exposed to an agent that has a risk of causing tissue injury. In a third aspect, methods are provided for identifying an agent as having a risk of causing tissue injury to a vertebrate subject. In a fourth aspect, kits are provided for practicing the methods of above-listed aspects. The contents of this ABSTRACT are not intended to in anyway limit the scope of the inventions claimed herein.

Abstract: Disclosed herein is a novel forward mutation assay based on 5-fluorouracil (5-FU) resistance which utilizes a strain of Salmonella typhimurium derived from the Ames strain TA100. More specifically, the invention provides a high throughput alternative to the standard Ames mutation assay for the evaluation of the genotoxicity activity of compounds during an early stage of the drug development process. The invention also identifies the upp locus as a mutational target that is capable of detecting a diverse spectrum of mutagenic events and further describes a S. typhimurium tester strain, designated FU100 (his+, rfa, ?uvrB, pkM101, 5-fluorouridine resistant) for use in the assay of the invention.

Abstract: HCV mutations emerged in chimpanzees treated with a N5B polymerase inhibitor (Compound A) or a NS3 protease inhibitor (Compound B). Short term treatment with Compound A was followed by the initial emergence of an HCV with a S282T polymerase mutation following treatment. Short term treatment with Compound B selected for HCV with a R155K or D168T protease mutation.