Microstructure-based Finite Element Modelling and Characterisation of Bovine Trabecular Bone

1 Introduction The mechanical behaviour of trabecular bone is dependent on both the properties of individual trabeculae as well as the three-dimensional architecture into which they are arranged. Hence, a comprehensive study of trabecular bone requires the consideration of microscopic as well as macroscopic length scales. Nanoindentation is a technique particularly suited to the mechanical characterisation of single trabecula[1?3] owing to the impracticalities of isolating individual tra- becu…     

Serendipitous discovery of an unexpected rearrangement leads to two new classes of potential protease inhibitors

The pathogenesis of a range of human diseases arises from the aberrant activity of proteolytic enzymes. Agents capable of selectively modulating the activity of these enzymes are of potential therapeutic value. Thus, there is a continuing need for the design of scaffolds that can be used in the development of new classes of protease inhibitors. We describe herein the serendipitous discovery of an unexpected rearrangement that leads to the formation of two novel templates that can be used in the design of protease inhibitors.     

Some effects of metal ions on DNA structure and genetic information transfer

The reaction of metal ions with nucleic acids can lead to a variety of dramatic effects on nucleic acid structure, e.g., crosslinking of the polymer strands, degradation to oligomers and monomers, stabilization or destabilization, and the mispairing of bases. These effects have important implications for genetic information transfer. Metal ions are involved in many aspects of this transfer; we are presently concerned with the effect of metal ions on the orientation of the active site of RNA polymerase. Many of the effects of metal ions on nucleic acid structure involve changes in the conformation of the macromolecules. We have found that conditions that have been used to convert B DNA to Z DNA lead to at least two other conformational changes, and phase diagrams delineate the realms of stability of each of the forms. We have carried out a number of studies that demonstrate that the conversion of B to Z DNA is very closely correlated with a substantial decrease in the ability of the DNA to act as a template for RNA synthesis. A portion of this paper has been taken from another paper on “Changes of Biological Significance Induced by Metal Ions in the Structure of Nucleic Acids,” published in Annali dell' lstituto Superiore di Sanita.     

Relationship between histology,development and tumorigenesis of mammary gland in female rat

The mammary gland is a dynamic organ that undergoes structural and functional changes associated with growth, reproduction, and post-menopausal regression. The postnatal transformations of the epithelium and stromal cells of the mammary gland may contribute to its susceptibility to carcinogenesis. The increased cancer incidence in mammary glands of humans and similarly of rodents in association with their development is believed to be partly explained by proliferative activity together with lesser degree of differentiation, but it is not completely understood how the virgin gland retains its higher susceptibility to carcinogenesis. During its developmental cycle, the mammary gland displays many of the properties associated with breast cancer. An early first full-term pregnancy may have a protective effect. Rodent models are useful for investigating potential breast carcinogens. The purpose of this review is to help recognizing histological appearance of the epithelium and the stroma of the normal mammary gland in rats, and throughout its development in relation to tumorigenic potential.