Influence of sample return time and ambient temperature on the performance of an immunochemical faecal occult blood test with a new buffer for colorectal cancer screening.

The haemoglobin concentration measured by faecal immunochemical tests (FIT) may be decreased in cases of delayed sample return or high temperature. It is an issue of great importance. The aim of this study was to investigate the effects of sample return time and of season on the performance of an FIT (FOB-Gold) with a new buffer.

Diagnostic yield of a one sample immunochemical test at different cut-off values in an organised screening programme for colorectal cancer.

Background: Quantitative immunochemical faecal occult blood tests have become the recommended tests for colorectal cancer screening. The aim of this study was to complete our knowledge on the performance of one of the quantitative immunochemical tests available, FOB-Gold, and to propose a possible strategy for an organised screening programme.

Patients And Methods: Within the French organised screening programme, 23,231 average-risk individuals, aged 50-74 performed both a 3-day Hemoccult test and a 1-day FOB-Gold test.

Comparison between a guaiac and three immunochemical faecal occult blood tests in screening for colorectal cancer.

Background: The aim of this study was to compare the performance of the guaiac-based faecal occult blood test (G-FOBT), with that of three immunochemical faecal occult blood tests (I-FOBT) which allow automatic interpretation.

Patients And Methods: Under the French organised screening programme, 85,149 average-risk individuals aged 50-74 participating in the third screening round, performed both the G-FOBT (Hemoccult-II test) and one of the I-FOBTs: FOB-Gold, Magstream and OC-Sensor.

Results: Given the chosen threshold, the positivity ratio between the different I-FOBTs and the G-FOBT was 2.

Positivity rates and performances of immunochemical faecal occult blood tests at different cut-off levels within a colorectal cancer screening programme.

Background: Immunochemical faecal occult blood tests have greater sensitivity for colorectal cancer screening than guaiac-based tests; however the number of positive tests required is still under discussion.

Methods: A direct comparison of Hemoccult II with two immunochemical quantitative tests (OC-Sensor and FOB-Gold) using a 2-sample strategy was performed in over 30,000 patients undergoing colorectal cancer screening in France.

Results: Positivity ratio between immunochemical tests and Hemoccult II varied between 2.

Sufficient levels of quinine in the serum circumvent the multidrug resistance of the human leukemic cell line K562/ADM.

Reversal of multidrug drug resistance (MDR) has been achieved in vitro by a variety of agents including verapamil, quinidine, cyclosporine A, and amiodarone. The toxicity of these agents precludes the achievement of sufficient levels in the serum to circumvent efficiently the MDR in vivo. The authors previously demonstrated that quinine, the widely used antimalarial agent, is able to reverse primary resistance of rat colon cancer cells to anthracyclines.

P-glycoprotein expression and in vitro reversion of doxorubicin resistance by verapamil in clinical specimens from acute leukaemia and myeloma.

The expression of the P-glycoprotein which is associated with the development of multidrug resistance in various cell lines was investigated in 87 fresh acute leukaemia and multiple myeloma samples using the specific mouse monoclonal antibody MRK16 in an indirect immunofluorescence assay. Considering a 10% positive cell cut-off value, a heterogeneous expression of P-glycoprotein was observed in 5/22 (22.7%) de novo acute leukaemias, 7/22 (31.

Quinine circumvents the doxorubicin resistance of a multidrug resistant human leukemic cell-line, K562/DXR.

Reversal of multidrug resistance (MDR) has been obtained in vitro by a variety of agents but clinical use of these resistance modifiers is hampered by their own toxicity. Quinine, the natural isomer of quinidine, is demonstrated to circumvent doxorubicin (DXR) resistance of an MDR human leukemic cell-line, K562/DXR. In culture medium, quinine (5 mu/ml or more) significantly increases cytotoxicity and accumulation of DXR in the resistant cells but not in the parental sensitive cells.