Weight of evidence approach using a TK gene mutation assay with human TK6 cells for follow-up of positive results in Ames tests: a collaborative study by MMS/JEMS.

Background: Conflicting results between bacterial mutagenicity tests (the Ames test) and mammalian carcinogenicity tests might be due to species differences in metabolism, genome structure, and DNA repair systems. Mutagenicity assays using human cells are thought to be an advantage as follow-up studies for positive results in Ames tests. In this collaborative study, a thymidine kinase gene mutation study (TK6 assay) using human lymphoblastoid TK6 cells, established in OECD TG490, was used to examine 10 chemicals that have conflicting results in mutagenicity studies (a positive Ames test and a negative result in rodent carcinogenicity studies).

Integrated approach to testing and assessment for predicting rodent genotoxic carcinogenicity.

We investigated the performance of an integrated approach to testing and assessment (IATA), designed to cover different genotoxic mechanisms causing cancer and to replicate measured carcinogenicity data included in a new consolidated database. Genotoxic carcinogenicity was predicted based on positive results from at least two genotoxicity tests: one in vitro and one in vivo (which were associated with mutagenicity categories according to the Globally Harmonized System classification). Substances belonging to double positives mutagenicity categories were assigned to be genotoxic carcinogens.

Evaluation of the sensitivity and specificity of in vivo erythrocyte micronucleus and transgenic rodent gene mutation tests to detect rodent carcinogens.

Sensitivity and/or specificity of the in vivo erythrocyte micronucleus (MN) and transgenic rodent mutation (TGR) tests to detect rodent carcinogens and non-carcinogens were investigated. The Carcinogenicity and Genotoxicity eXperience (CGX) dataset created by Kirkland et al. was used for the carcinogenicity and in vitro genotoxicity data, i.

Developments for a growing Japanese patient population: facilitating new technologies for future health care.

Lung cancer, COPD and cardiovascular diseases are highlighted as some of the most common disease that cause mortality, and for that reason are the most active areas for drug development. This perspective paper overviews the urgent need to develop a health care system for a rapidly growing patient population in Japan, including forthcoming demands on clinical care, expecting outcomes, and economics. There is an increasing requirement to build on the strengths of the current health care system, thereby delivering urgent solutions for the future.

Studies on substantially increased proteins in follicular fluid of bovine ovarian follicular cysts using 2-D PAGE and MALDI-TOF MS.

Background: The objective of this study was to identify substantially increased proteins in bovine cystic follicular fluid (FF) in order to clarify the pathology and etiology of bovine ovarian follicular cysts (BOFC).

Methods: Proteins in normal and cystic FF samples were subjected to two-dimensional polyacrylamide gel electrophoresis (2-D PAGE) and were compared using silver stained gel images with PDQuest image analysis software. Peptides from these increased spots were analyzed by matrix assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF MS), and were identified based on the NCBI database by a peptide mass fingerprinting method.