[Online tool to prepare patient for colonoscopy; development and implementation of a patient-education app]. / Digitaal de patiënt voorbereiden op coloscopie.

Optimal patient education prior to colonoscopy is essential for an optimal outcome of the procedure. Patients benefit from adequate information regarding laxatives, risks and alternatives, and must provide informed consent. The endoscopist also has to have access to patient data in advance of the procedure in order to carry out an adequate risk assessment for the use of sedation. Most centres in the Netherlands usually make use of a pre-endoscopy consultation to exchange this information, but here is now pressure on this practice because the number of colonoscopies is increasing rapidly as a result of the introduction of the national screening programme for colorectal cancer.

Using genome-wide CRISPR library screening with library resistant DCK to find new sources of Ara-C drug resistance in AML.

Acute myeloid leukemia (AML) can display de novo or acquired resistance to cytosine arabinoside (Ara-C), a primary component of induction chemotherapy. To identify genes capable of independently imposing Ara-C resistance, we applied a genome-wide CRISPR library to human U937 cells and exposed to them to Ara-C. Interestingly, all drug resistant clones contained guide RNAs for DCK. To avoid DCK gene modification, gRNA resistant DCK cDNA was created by the introduction of silent mutations. The CRISPR screening was repeated using the gRNA resistant DCK, and loss of SLC29A was identified as also being capable of conveying Ara-C drug resistance. To determine if loss of Dck results in increased sensitivity to other drugs, we conducted a screen of 446 FDA approved drugs using two Dck-defective BXH-2 derived murine AML cell lines and their Ara-C sensitive parental lines. Both cell lines showed an increase in sensitivity to prednisolone. Guide RNA resistant cDNA rescue was a legitimate strategy and multiple DCK or SLC29A deficient human cell clones were established with one clone becoming prednisolone sensitive. Dck-defective leukemic cells may become prednisolone sensitive indicating prednisolone may be an effective adjuvant therapy in some cases of DCK-negative AML.