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BTR-270, a gypsy moth (Lymantria dispar) brush border membrane molecule that binds Bacillus thuringiensis (Bt) Cry1A toxins with high affinity, was purified by preparative gel electrophoresis. Rabbit antibodies specific for the Bt toxin-binding molecule were raised. Attempts to label BTR-270 by protein-directed techniques were futile, but it was degraded by proteases with broad specificity indicating the presence of a peptide. Carbohydrate was detected by labeling with digoxigenin hydrazide following periodate oxidation. Mild alkaline hydrolysis destroyed toxin and antibody binding, suggesting O-linked glycans are involved in the activity. GC/MS composition analysis showed that the predominant sugars were galactose, glucose, and N-acetyl galactosamine with lesser amounts of N-acetyl glucosamine, glucuronic acid, xylose, and fucose. The carbohydrate moiety accounted for 73% of its total mass. Amino acid analysis showed a high content of aspartic/asparagine, threonine, and serine residues in the protein moiety. The purified glycoconjugate was not visualized using Coomassie or silver staining procedures, but stained "blue" using the cationic dye Stains-all. BTR-270 was labeled with biotin and used as a diagnostic probe for screening and identifying toxins that bind to the receptor. Toxin-binding kinetics obtained using a biosensor demonstrated that the receptor binds Cry1Aa and Cry1Ab toxins with high affinity, and displays a weaker affinity for Cry1Ac, in correlation with the toxicity of these toxins towards gypsy moth. Arch., (Copyright 2001 Wiley-Liss, Inc.)

Controlled trials to evaluate mass screening programs for cancer detection have been singularly lacking. High cost, lack of medical manpower, and low yield have contributed to this problem. A new program in cancer detection (CANSCREEN) has been developed jointly by The Fox Chase Cancer Center in Philadelphia and the Preventive Medicine Institute in New York City. This program attempts to provide a quality cancer-detection examination with increased cost effectiveness. Features include: 1) a self-administered questionnaire on medical history, symptoms, and risk factors; 2) nonphysican examiners; 3) risk-facotr analysis with a predetermined decision logic to determine type and periodicity of examination; and 4) primary intervention (health education). This collaborative program between two institutions in two cities demonstrates the feasibility of introducing similar programs elsewhere. A data base shared by cooperating centers permits information on all patients to be used for evaluation of new techniques, end results, etc. A randomized controlled trial has been designed to evaluate the effectiveness and efficiency of the questionnaire alone and of the questionnaire and examination.