Seasonal changes in adaptations associated with winter coping strategies have been frequently studied. Central among the suite of energy-saving, winter-coping strategies is the suspension of reproductive activities. The inhibition of reproduction by nontropical rodents is mediated by daylength changes. Although balanced annual energy budgets are critical, survival and subsequent reproductive su...

OBJECTIVE Hamster cheek pouches (HCP) with various degrees of 9,10-dimethyl-1,2-benzanthracene (DMBA)-induced dysplasia and malignancies were imaged with OCT/ODT in vivo and in vitro to assess the potential for three-dimensional high-resolution optical localization of airway malignancy. BACKGROUND DATA Optical coherence tomography (OCT)/optical doppler tomography (ODT) provide potential capab...

It has been reported that ornithine decarboxylase (ODC) and histidine decarboxylase (HDC) levels are high in malignant growing tissues and it is suggested that diamines (putrescine and histamine) may play an important role in the tumor development process1). Schayer2) and Kahlson and Rosengren3) suggested that the rapid increase in HDC activity (e.g. in tumors) was associated with " inducible H...

Methods have been described for the preparation of tritiated carcinogenic polycyclic aromatic hydrocarbons of high specific activity by the Wilzbach method. A large num ber of highly radioactive impurities were produced during the exposure to tritium gas, and extensive purification was required. This was achieved by column chromatography followed by various paper Chromatographie systems with so...

It was shown in 1953 by Engelbreth-Holm and Asboe-Hansen (4) that cortisone, injected intraperitoneally, caused a definite reduction in the de velopment of tumors and an increased latent pe riod in albino mice of strain ST/Eh painted once with 9,10-dimethyl-l,2-benzanthracene (DMBA). Similar results were obtained by Boutwell and Rusch (3) with carcinomas induced by benzpyrene. Sulzberger, Herrm...

In a solvent system of 10(-2)m phosphate buffer (pH 6.8)-ethanol (2:1, v/v) and in an iodine-induced reaction, the polycyclic hydrocarbons [(3)H]3,4-benzpyrene and [(3)H]3,4-BP/[(3)H]9, 10-dimethyl-1,2-benzanthracene (DMBA) can be covalently linked to deoxyribonucleic acid (DNA) at room temperature. By stepwise addition of the hydrocarbon and repeating the reaction two to three times after isol...

The carcinogens 9,10-dime thy 1-1,2-benzanthracene, 20-methylcholanthrene, 3,4benzpyrene, 1,2,5,6-dibenzanthracene, 1,2-benzanthracene, and 2-anthramine have been tested topically in the Syrian golden hamster. The mouse skin tumor-promoting agents, croton oil and polyoxyethylene sorbitan monostearate (Tween 60), have been tested on hamster skin following a single applica tion of 9,10-dimethyl-l...

Endostatin, a Mr 20,000 fragment of collagen XVIII, potently inhibits the growth of experimental tumors implanted in mice. Here we report the cloning, expression, and antitumor activity of the rat form of endostatin. When tested on breast carcinomas arising in female virgin rats after intragastric administration of 9,10-dimethyl-1,2-benzanthracene (DMBA), endostatin induced significant inhibiti...

The monitoring of pancreatic ductal adenocarcinoma (PDAC) in high-risk populations is essential. Cathepsin E (CTSE) is specifically and highly expressed in PDAC and pancreatic intraepithelial neoplasias (PanINs), and its expression gradually increases along with disease progression. In this study, we first established an in situ 7,12-dimethyl-1,2-benzanthracene (DMBA)-induced rat model for PanI...