Biomedical subjects

Youzhi Li

Publications and source records attributed to Youzhi Li.

3 recordsLinked to original sources

PubMed2003

Selective killing of cancer cells by beta -lapachone: direct checkpoint activation as a strategy against cancer.

Most chemotherapeutic drugs kill cancer cells by indirectly activating checkpoint-mediated apoptosis after creating nonselective damage to DNA or microtubules, which accounts for their toxicity toward normal cells. We seek to target cancer cells by directly activating checkpoint regulators without creating such damage. Here, we show that beta-lapachone selectively induces apoptosis in cancer cells without causing the death of nontransformed cells in culture. This unusual selectivity against cancer cells is preceded by activation of S-phase checkpoint and selective induction of E2F1, a regulator of checkpoint-mediated apoptosis. This study suggests direct checkpoint activation as a strategy against cancer.

Antibiotics, Antineoplastic↗

PubMed2003

Scale-invariant recognition of three-dimensional objects by use of a quasi-correlator.

A method of scale-invariant recognition of three-dimensional (3-D) objects is presented. Several images of the observed scene are recorded under white-light illumination from several different points of view and compressed into a single complex two-dimensional matrix. After filtering with a single scale-invariant filter, the resultant function is then coded into a computer-generated hologram (CGH). When this CGH is coherently illuminated, a correlation space is reconstructed in which light peaks indicate the existence and location of true targets in the tested 3-D scene. The light peaks are detectable for different sizes of the true objects, as long as they are within the invariance range of the filter. Experimental results in a complete electro-optical system are presented, and comparisons with other systems are investigated by use of computer simulation.

Journal Article↗

PubMed2002

Object recognition using three-dimensional optical quasi-correlation.

A novel method of three-dimensional (3-D) object recognition is proposed. Several projections of a 3-D target are recorded under white-light illumination and fused into a single complex two-dimensional function. After proper filtering, the resulting function is coded into a computer-generated hologram. When this hologram is coherently illuminated, a correlation space is reconstructed such that light peaks indicate the existence and locations of true targets in the observed 3-D scene. Experimental results and comparisons with results of another 3-D object recognition technique are presented.

Journal Article↗