Synthesis and biological results of the technetium-99m-labeled 4-nitroimidazole for imaging tumor hypoxia.

1-(4-Nitroimidazole-1-yl)-propanhydroxyiminoamide (N4IPA) was synthesized. The biodistribution of 99mTc-N4IPA in mice bearing S180 tumor demonstrated that the complex showed accumulation in tumor and slow clearance from it. The tumor-to-tissue uptake ratios increase with time.

The structure of a Bcl-xL/Bim fragment complex: implications for Bim function.

After antigen-driven expansion, the majority of T cells involved in an immune response die rapidly by apoptosis dependent on the Bcl-2 related proteins, Bim and Bax or Bak. The details of how these proteins are activated and interact are still unclear. The crystal structure of mouse Bcl-x(L) bound to a long helical fragment of Bim indicates that the structure of Bim is very different from proteins with a Bcl-2-like fold and may leave the BH3 region of Bim constitutively exposed.

Identification of uteroglobin-related protein 1 and macrophage scavenger receptor with collagenous structure as a lung-specific ligand-receptor pair.

High in normal (HIN)-1 is a secreted protein highly expressed in normal breast epithelium and down-regulated in breast carcinomas. By searching GenBank expressed sequence tag databases, we identified HIN-2, a protein homologous to HIN-1. HIN-2 is identical with a recently identified protein called uteroglobin-related protein 1 (UGRP1).

Atomic force microscopy study of chromosome surface structure changed by protein extraction.

We applied atomic force microscopy (AFM) to investigate the surface structure of barley chromosome in combination with a chemical treatment method. As a result, we have obtained high-resolution topographic images of granular structures with a diameter of ca. 50 nm on the surface of critical-point dried metaphase chromosomes.

Alternate interactions define the binding of peptides to the MHC molecule IA(b).

We have solved the crystal structure of the MHCII molecule, IA(b), containing an antigenic variant of the major IA(b)-binding peptide derived from the MHCII IEalpha chain. The four MHC pockets at p1, p4, p6, and p9 that usually bind peptide side chains are largely empty because of alanines in the peptide at these positions. The complex is nevertheless very stable, apparently because of unique alternate interactions between the IA(b) and peptide.