Oral contraceptive use and smoking are risk factors for relapse in Crohn's disease. The Canadian Mesalamine for Remission of Crohn's Disease Study Group.

Background & Aims: Lifestyle factors have been shown to influence prognosis in Crohn's disease. The purpose of this study was to prospectively assess the effects of smoking and oral contraceptive use on clinical relapse rates.

Methods: Placebo-treated patients formed a prospective cohort, followed up for 48 weeks or until relapse.

Multidrug resistance-modifying components in human plasma with potential clinical significance.

P-Glycoprotein (P-gp) and multidrug resistance protein (MRP) are plasma membrane associated proteins which can confer multidrug resistance (MDR) to cancer cells by lowering the intracellular amount of drug. Although clinical trials with MDR-reverting agents have been initiated, not much attention has been paid to blood components which may modulate the activity of P-gp or MRP. The present investigation was performed to identify and characterize blood components which may influence the drug content and the drug cytotoxicity of MDR cells.

The tumor microenvironment: possible role of integrins and the extracellular matrix in tumor biological behavior of intratubular germ cell neoplasia and testicular seminomas.

In the present study, we examined the distribution of integrin subunits and extracellular matrix proteins in normal testis, intratubular germ cell neoplasia (ITGCN), and primary and metastatic seminomas. Compared to normal testis in ITGCN, Sertoli cells showed increased expression of alpha 3, alpha 6, and beta 1 integrin subunits. Malignant intratubular germ cells stained for alpha 3, alpha 6, and beta 1 integrin subunits.

cis-diamminedichloroplatinum(ii) resistance in vitro and in vivo in human embryonal carcinoma cells.

In the embryonal carcinoma cell line Tera and its 3.7-fold cis-diamminedichloroplatinum(II) (CDDP)-resistant subline, Tera-CP, parameters were studied that might have changed in relation to induction of CDDP resistance. Phenotypes of both lines were embryonal carcinoma.

Formation by diethylnitrosamine and persistence of O4-ethylthymidine in rat liver DNA in vivo.

The formation by diethylnitrosamine (DEN) and persistence of O4-ethylthymidine in rat liver DNA in vivo has been studied using enzymic hydrolysis of DNA, cation exchange column chromatography and thin-layer chromatography (TLC). The amount of O4-ethylthymidine represented about 1% of the total ethylation; its half-life in vivo was 19 (range 16--24) days, the same value as obtained for O2-ethylthymidine. The persistence of O2- and O4-ethylthymidine, rather than the rapid removal of O6-ethylguanine, favours the former miscoding base adducts as relevant molecular lesions in rat liver carcinogenesis.