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Theo J Ruers

Publications and source records attributed to Theo J Ruers.

3 recordsLinked to original sources

Decrease in circulating anti-angiogenic factors (angiostatin and endostatin) after surgical removal of primary colorectal carcinoma coincides with increased metabolic activity of liver metastases.

Removal of a primary colorectal tumor resulted in an increase in metabolic activity in its liver metastasis. Concomitantly, levels of angiostatin and endostatin in urine and plasma, respectively, dropped. This finding indicates that the primary tumor suppressed angiogenesis in its distant metastasis, and that removal of the primary lesion caused a flare-up in vessel neoformation and, thus, enhanced metabolic activity in its liver metastasis.

Aged↗

Effective migration of antigen-pulsed dendritic cells to lymph nodes in melanoma patients is determined by their maturation state.

Dendritic cells are the professional antigen-presenting cells of the immune system. To induce an effective immune response, these cells should not only express high levels of MHC and costimulatory molecules but also migrate into the lymph nodes to interact with naïve T cells. Here, we demonstrate that in vitro-generated mature, but not immature dendritic cells, efficiently migrate into the T-cell areas of lymph nodes of melanoma patients. This difference is confirmed by in vitro studies, in which immature dendritic cells are strongly adherent, whereas mature dendritic cells remain highly motile. Our present findings demonstrate that the ability of dendritic cells to mount a proper immune response correlates with their ability to migrate both in vitro and in vivo.

Antibodies, Monoclonal↗

Method for quantitation of dynamic MRI contrast agent uptake in colorectal liver metastases.

PURPOSE: To investigate the reproducibility of dynamic contrast-enhanced MRI (DCE-MRI) in colorectal liver metastases using a vascular normalization function (VNF) from pixels in the spleen and to compare this with a technique using an arterial input function (AIF) from pixels in the aorta. MATERIALS AND METHODS: DCE-MRI with gadolinium-DTPA (Gd-DTPA) was performed in patients with colorectal liver metastases. The VNF and AIF were determined using an automated algorithm. The average Gd-DTPA uptake rate (k(ep)) was calculated for the metastases using a physiological pharmacokinetic model. The protocol was repeated on a second day to calculate the repeatability coefficient of the measurements of k(ep). RESULTS: Using the VNF from the spleen the overall mean k(ep) of the two sessions for 11 patients was 0.033 per second and the repeatability coefficient was 0.009 per second. Using the AIF from the aorta these values were 0.031 per second and 0.028 per second, respectively. CONCLUSION: The mean Gd-DTPA uptake rate using a VNF taken from the spleen can be determined with adequate reproducibility in colorectal liver metastases. The use of a VNF from pixels in the spleen is better than an AIF from pixels in the aorta in terms of reproducibility, and is recommended when this DCE-MRI technique is used for prediction and monitoring of therapy outcome in colorectal liver metastases.

Adult↗