In this study, 602 samples were tested by the following assays performed at the animal facilities (Cedeme) of the Federal University of São Paulo (UNIFESP): 385 for dermal irritability, 90 for ocular irritability (discontinued in 1995), 31 for systemic toxicity by injection, 26 for oral acute toxicity, 15 for toxicity by intracutaneous injection, 15 for skin sensitization, 15 for toxicity of se...

Paraquat (1,1'-dimethyl-4,4'-bipyridylium dichloride) is a widely used herbicide and is highly toxic to human and animals. The mechanisms of paraquat toxicity involve the generation of superoxide anion through the process of redox cycling. NADPH-cytochrome P450 oxidoreductase (POR) has been reported to be a major enzyme for one-electron reduction of paraquat that initiates the redox cycling. Re...

BACKGROUND/AIMS Retinal toxicity is one of the most commonly discussed and concerning adverse effects of vigabatrin (VGB). The present study explored the relationship between the VGB elicited retinal toxicity, photopic exposure, and taurine deficiency, aiming at screening for risk factors to minimize the adverse effects of VGB. METHODS The effects of VGB on function and morphology of mouse re...

Intracellular bacteria use a variety of strategies to evade degradation and create a replicative niche. Legionella pneumophila is an intravacuolar pathogen that establishes a replicative niche through the secretion of more than 300 effector proteins. The function of most effectors remains to be determined. Toxicity in yeast has been used to identify functional domains and elucidate the biochemi...

The determination of single high doses of active pharmaceutical ingredients (API) is used mostly to fulfill regulatory demands. Oral LD(50) values in animals for over 300 API were compared to the minimal effective therapeutic doses (METD) in humans in order to find a correlation between animal and human data. The highest correlation between human METD and animal LD(50) was found for the dog (R=...

Acute systemic toxicity studies are carried out in many sectors in which synthetic chemicals are manufactured or used and are among the most criticized of all toxicology tests on both scientific and ethical grounds. A review of the drivers for acute toxicity testing within the pharmaceutical industry led to a paradigm shift whereby in vivo acute toxicity data are no longer routinely required in...

Introduction The use of preclinical imaging is increasing as the power of these tools has been demonstrated through a variety of animal models that enable early drug screening and decision making. Anatomical, molecular, and functional imaging can provide valuable information to help understand the activity of compounds in development, supporting studies evaluating compound activity (mechanism o...

Bis-aryloxadiazoles are common scaffolds in medicinal chemistry due to their wide range of biological activities. Previously, we identified a 1,2,4-bis-aryloxadiazole that blocks mammary branching morphogenesis through activation of the aryl hydrocarbon receptor (AHR). In addition to defects in mammary differentiation, AHR stimulation induces toxicity in many other tissues. We performed a struc...

Characterization of secondary metabolites and cytotoxic testing Haliclona sp. against T47D breast cancer cells were conducted in this study. The objective was to assess the cytotoxicity identify functional groups involved. research methods employed included maceration, partitioning, phytochemical testing, toxicity using BSLT method, separation through flash column chromatography (FCC), MTT char...