Development and validation of a human bronchial epithelial spheroid model to study respiratory toxicity in vitro.

The use of laboratory animals in research has been extensively criticized. While most of the critique has been centered around the ethical aspect, also the economic and scientific aspects have been frequently mentioned as points of concern. As a result, the use of alternative methods has gradually become more enticing.

Triglyceride/high-density lipoprotein cholesterol (TG/HDL-C) index as a reference criterion of risk for metabolic syndrome (MetS) and low insulin sensitivity in apparently healthy subjects.

Aim: To evaluate if the TG/HDL-C index can be considered as a reference criterion of MetS and low insulin sensitivity in apparently healthy subjects.

Methods: The subjects were Mexican mestizos who resided in Puebla City, Mexico, who were anthropometrically, biochemically, and clinically characterized. The TG/HDL-C index was calculated by dividing triglyceride (TG) levels by HDL-C levels.

Avoiding tolerance against prostatic antigens with subdominant peptide epitopes.

A potential novel therapy for prostate cancer is the induction of immune responses to normal prostate-associated antigens (PAA). One approach is to use synthetic peptides from PAA to educate T cells as a means of developing a defined and specific immunotherapy for prostate cancer. A likely major hurdle when using normal PAA for this type of therapy is the tolerance that the immune system may already have for PAA.

Properties of an Escherichia coli K-12 mutant defective in the transport of arginine and ornithine.

A canavanine-resistant mutant strain, defective in the transport of arginine and ornithine, was isolated and characterized. Experiments presented show that both the kinetics of influx and the steady state of accumulation of arginine and ornithine are affected by the mutation, whereas the activity of other related transport systems remains unchanged. On the basis of competitive studies, it is concluded that L-canavanine can inhibit efficiently the arginine-specific uptake system.

Independent regulation of transport and biosynthesis of arginine in Escherichia coli K-12.

From an arginine auxotrophic strain, a mutant was isolated which is able to utilize d-arginine as a source of l-arginine and shows a high sensitivity to inhibition of growth by canavanine. Transport studies revealed a four- to five-fold increased uptake of arginine and ornithine in cells from the mutant strain. The kinetics of entry of arginine and ornithine evidenced elevated maximal influx values for the arginine- and ornithine-specific transport systems.