Biomedical subjects

H-B Yu

Publications and source records attributed to H-B Yu.

3 recordsLinked to original sources

PubMed2007

Alterations of p16INK4a tumour suppressor gene in mucoepidermoid carcinoma of the salivary glands.

Mucoepidermoid carcinoma (MEC) is common in the salivary glands, but alterations of the p16(INK4a) tumour suppressor gene are largely unknown. The aim of this study was to analyse p16(INK4a) gene alterations in MEC, and evaluate their significance for carcinogenesis. Thirty-eight salivary glands with MEC and six normal salivary glands were studied for p16(INK4a) alterations. In the MEC-affected group, there were 23.7% (9/38) and 13.2% (5/38) cases of homozygous deletion, and 5.3% (2/38) and 2.6% (1/38) cases of point mutation in p16(INK4a) exon 1 and exon 2, respectively. Hypermethylation of the p16(INK4a) gene promoter was found in 13 cases (13/38, 34.2%). Alterations of the p16(INK4a) gene were not found in the normal salivary glands. These findings suggest that the main mechanisms of inactivation of the p16(INK4a) gene in MEC of the salivary glands are promoter hypermethylation and homozygous deletion.

Adolescent↗

PubMed2006

Scanning tunneling spectroscopy of Ag films: the effect of periodic versus quasiperiodic modulation.

By using scanning tunneling spectroscopy to probe a silver thin film that contains both periodic and quasiperiodic modulation, and by using Fourier analysis, we unravel the influences of individual Fourier components of the scattering potential (periodic versus quasiperiodic) on the electronic structure of a one-dimensional quasiperiodically modulated thin Ag film. Along the periodically modulated direction, a Bragg reflection-induced energy gap is observed in k space. On the other hand, the exotic E vs k spectrum with many minigaps was observed along the quasiperiodic direction.

Journal Article↗

PubMed2004

Building Pb nanomesas with atomic-layer precision.

We demonstrate a novel scheme for manipulating metallic nanostructures involving a macroscopic number of atoms, yet with precise control in their local structures. The scheme entails a two-step process: (a) a triggering step using a scanning tunneling microscope, followed by (b) self-driven and self-limiting mass-transfer process. By using this scheme, we construct Pb nanomesas on Si(111) substrates whose thickness can be controlled with atomic-layer precision. The kinetic barrier for the mass transfer and the underlying mechanism behind this novel manipulation are determined.

Journal Article↗