The purpose of this study was to determine whether protein tyrosine kinase, a ubiquitous family of intracellular signaling enzymes that regulates endothelial cell function, modulates bradykinin- and substance P-induced increase in macromolecular efflux from the intact hamster cheek pouch microcirculation. Using intravital microscopy, I found that suffusion of bradykinin or substance P (each, 0....

The first goal of this study was to determine whether chronic injection of nicotine alters endothelium-dependent arteriolar dilatation. We measured the diameter of cheek pouch resistance arterioles (approximately 50 microm in diameter) in response to endothelium-dependent (acetylcholine and ADP) and -independent (nitroglycerin) agonists in control hamsters and hamsters treated with nicotine (2 ...

Pouches from three experimental and one control animal were excised for analysis at various times during the first week and thereafter each week of carcinogen application (9,10-dimethyl-l ,~-benzanthracene) until the 131h week, at which time large tumors were present in all remaining aninmls. IIistologic progression from normal through inflanmmtion, uniform hyperplasia, localized premalignant h...

Immunophotodiagnosis uses a fluorescence-labeled monoclonal antibody (MAb) that recognizes a tumor-associated antigen to image the fluorescence emitted from the fluorophore-bound MAb that has localized in the tissue. It may be used to diagnose malignant or precancerous lesions, to delineate the margins for tumor resection, or as a feedback mechanism to assess response to treatment. In oral prec...

Optical coherence tomography (OCT)/optical Doppler tomography (ODT) provides real-time in vivo high-resolution (10-microm) imaging of tissues and real-time spatially resolved blood flow in microvasculature. Hamster cheek pouches with induced dysplasia and malignancies were imaged with OCT/ODT to assess the potential for application to airway malignancy. In 22 Golden Syrian hamsters, 0.5% 9,10-d...

Heterotransplantation of 1.0 X IO7AK-4 cells of AKR mice into cheek pouches of normal and cortisone-treated adult Syrian hamsters resulted in measurable but tran sient growth; small vascular tumors which appeared at 5-7 days regressed completely by 10-14 days. Noncortisonized hamsters vigorously rejected second-set grafts, which failed to vascularize, in considerably less time, in either the pr...

Laser-induced fluorescence has been used to measure tissue levels of chloroaluminum sulfonated phthalocyanine in vivo in an implanted ham ster cheek pouch carcinoma tumor model. The drug was excited at 610 nm via a pulsed nitrogen laser-pumped dye laser, and fluorescence intensity was monitored at 684 nm for up to 30 days after drug administration. Data were acquired noninvasively with high tem...

In this study we use a multi-spectral digital microscope (MDM) to measure multi-spectral auto-fluorescence and reflectance images of the hamster cheek pouch model of DMBA (dimethylbenz[alpha]anthracene)- induced oral carcinogenesis. The multi-spectral images are analyzed both in the RGB (red, green, blue) color space as well as in the YCbCr (luminance, chromatic minus blue, chromatic minus red)...

BACKGROUND AND OBJECTIVE New techniques for non-invasive early detection and diagnosis of oral dysplasia and carcinoma are required. Our objective was to determine in the hamster cheek pouch model whether differentiation between the healthy tissue and the different stages of oral premalignancy and malignancy is possible using laser-induced fluorescence after tissue exposure to 5-Aminolevulinic ...

We have proposed and validated the hamster cheek pouch model of oral cancer for boron neutron capture therapy (BNCT) studies and shown that boronophenylalanine delivers potentially therapeutic 36.9 +/- 17.5 ppm boron to tumor tissue with tumor:normal tissue and tumor:blood ratios of 2.4:1 and 3.2:1, respectively. Here we report the first evidence of the usefulness of BNCT for the treatment of o...