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Background: Response to cisplatin-therapy is assumed to be related to the formation of platinum (Pt)-DNA adducts. Measurement of these adducts prior to therapy could be of value to improve cisplatin based cancer therapy. Materials and methods: We determined Pt-GG and Pt-AG adduct levels by use of 32P-postlabeling after ex vivo cisplatin treatment of fragments of head and neck squamous cell carcinoma (HNSCC) xenografts (five lines), and of tumor biopsies from patients with HNSCC (n = 8) and testicular cancer (n = 8). Results: Adduct levels in fragments (3 x 3 x 3 mm) exposed to 10 to 80 μM cisplatin for one hour, showed positive correlations with the in vivo response to cisplatin treatment (P < 0.05), as well as with the xenograft adduct levels observed after in vivo cisplatin treatment (P < 0.02). After an additional five-hour drug-free incubation period the correlations were absent. When patient tumor fragments were exposed ex vivo to 80 μM cisplatin for one hour, adduct levels were similar in HNSCC and testicular cancer. Persistence of adducts was observed for testicular cancer in the additional drug-free period. The adduct levels in the samples of two HNSCC patients who received cisplatin chemotherapy were in line with the hypothesis that higher adduct levels are associated with a better response. Conclusion: Our preliminary results show that analysis of DNA adducts following ex vivo drug treatment is a feasible approach towards a predictive assay, which warrants further investigation.

Background: Response to cisplatin-therapy is assumed to be related to the formation of platinum (Pt)-DNA adducts. Measurement of these adducts prior to therapy could be of value to improve cisplatin based cancer therapy. Materials and methods: We determined Pt-GG and Pt-AG adduct levels by use of 32P-postlabeling after ex vivo cisplatin treatment of fragments of head and neck squamous cell carcinoma (HNSCC) xenografts (five lines), and of tumor biopsies from patients with HNSCC (n = 8) and testicular cancer (n = 8). Results: Adduct levels in fragments (3 x 3 x 3 mm) exposed to 10 to 80 μM cisplatin for one hour, showed positive correlations with the in vivo response to cisplatin treatment (P < 0.05), as well as with the xenograft adduct levels observed after in vivo cisplatin treatment (P < 0.02). After an additional five-hour drug-free incubation period the correlations were absent. When patient tumor fragments were exposed ex vivo to 80 μM cisplatin for one hour, adduct levels were similar in HNSCC and testicular cancer. Persistence of adducts was observed for testicular cancer in the additional drug-free period. The adduct levels in the samples of two HNSCC patients who received cisplatin chemotherapy were in line with the hypothesis that higher adduct levels are associated with a better response. Conclusion: Our preliminary results show that analysis of DNA adducts following ex vivo drug treatment is a feasible approach towards a predictive assay, which warrants further investigation.

Objective: To examine the hypothesis that there is sufficient agreement between percentage of households purchasing selected foods using household budget surveys and percentage of individuals consuming these foods as determined in individual-based surveys to allow the former to act as a surrogate for the latter when estimating food chemical intakes using household budget data. Design: Database study. Setting: Databases from Sweden, The Netherlands, Ireland and the UK. Subjects: 319 foods (Sweden n = 60, The Netherlands n= 80, Ireland n=90, UK n=89). Results: Pearson correlations demonstrated a high degree of linear association between % households purchasing and % consumers (r=0.86). Regression analysis defined a close positive relationship between the two datasets (slope 0.95, intercept +2.74). Across countries, using the regression equation, the % households predicted % consumers to within 5% of the true value for between 33 and 48% of foods and to within 10% for between 53 and 78% of foods. Conclusions: Values for % households can be used as a crude surrogate for % consumers and can thus play a role in improving estimates of food additive intake.

Two powerful forces in Canada's health care system today are the rapidly growing seniors population and the trend toward community care. Recently, five hospitals in southwestern Ontario initiated a program designed to avert the admission of seniors to hospital and provide them with supports at home to maintain their health. Simultaneous research was conducted to assess the impact and effectiveness of the program.

In general practice, physicians are confronted with a newly diagnosed bladder cancer patient less than once a year. The role of general practitioners is restricted to just the initial phase of diagnosis and sometimes to the final, palliative stage of the disease. The diagnostic phase, as described in the guideline on urothelial carcinoma of the bladder, is hampered by the absence of clear signs and signals of bladder cancer. Painless gross haematuria is the most important clinical sign with a high predictive value, especially in older men. The value of microscopic haematuria is unclear and most patients with microscopic haematuria do not have a malignancy. Yet despite this, current guidelines still advise additional tests for all types of haematuria. However, we recommend that these patients are not subjected to such tests until their added value has been demonstrated.

We have developed two ELISA methods, i.e., enzyme immunoassay (EIA) and fluorescence immunoassay (FIA), for the semiquantitative detection of specific IgA and IgG antibodies directed against alpha-gliadin. The tests differ only for the enzyme substrate and, when optimized, could be used in large routine screening of celiac disease. Several serum samples from patients with celiac disease and gastrointestinal disorders as well as from control subjects were tested. Both methods gave good correlation with clinical data, were easily performed and had some specificity features, while FIA proved to be more sensitive.

To assess the individual chemosensitivity of human acute leukemias to anticancer agents, a rapid in vitro assay based on 125[I]-5-iodo-2'-deoxyuridine (125IUdR) incorporation into the DNA of neoplastic cells was tested. It was found that: a) the assay reflects the higher in vivo responsiveness of acute lymphoid leukemias with respect to acute non-lymphoid leukemias; b) samples from responder patients were more sensitive in vitro to antileukemic agents than were samples from non-responder patients; c) the assay in this study had an 86% accuracy in predicting response and a 90% accuracy in predicting resistance.