Glandular dysplasia in Barrett's esophagus may regress spontaneously but can also progress to cancer. The human telomerase RNA template and the human telomerase reverse transcriptase enzyme which do not, of themselves, correlate strongly with telomerase activity, are too often overexpressed in Barrett's dysplasia to predict individual cancer risk. This study relates telomerase activity, mucosal...

We have designed and built a nwel linear ion trap which permits storage of a large number of ions with reduced susceptibility to the second order Doppler effect caused by the BF conjbing fields. This new trap should store about 20 times the number of ions as a conventional RF trap with no corresponding increase in second order Doppler shift from the confining fleld. Other comparisons to etandar...

Using first-principles simulations on PbS and CdSe colloidal quantum dots, we find that surface defects form in response to electronic doping and charging of the nanoparticles. We show that electronic trap states in nanocrystals are dynamic entities, in contrast with the conventional picture wherein traps are viewed as stable electronic states that can be filled or emptied, but not created or d...

The force generated by the radiation pressure of a low power laser beam induces an optical trap which may be used to manipulate sperm. We studied the effect of the optical trap on sperm motility. A Nd:YAG laser beam was coupled to a conventional microscope and focused into the viewing plane by the objective lens. Sperm were caught in the trap and manipulated by a joy stick controlled motorized ...

Telomerase is a ribonucleoprotein enzyme that adds TTAGGG repeats onto human telomeres, preventing their shortening. The activation of this enzyme is an important step in cell immortalization and carcinogenesis and seems to represent a new and promising marker in cancer diagnosis and management. Telomerase activity is usually detected in cellular protein extract by the telomeric repeat amplific...

BACKGROUND There is accumulating evidence from the epidemiological field of telomere biology that telomere length plays an important role in the pathophysiology of cardiovascular disease. The RNA-dependent DNA polymerase, telomerase, is essential in regulating telomere length by acting as a reverse transcriptase. However, the relationship between telomerase activity and telomere length in cardi...

The ends of human chromosomes consist of several kilobases of simple telomeric repeats (TTAGGG)n (1). Telomeres are important for maintaining chromosome structure by protecting the chromosomes from DNA degradation, end-to-end fusions, rearrangements, and chromosome loss. Because DNA polymerases synthesize DNA in the 59 to 39 direction and require an RNA primer for initiation, telomeric DNA may ...