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Optical imaging would be desirable for cancer diagnostics since it can potentially resolve relevant oncological target structures in vivo. We therefore synthesised an αvβ3 targeted fluorochrome and imaged tumour xenografts with different αvβ3 expression levels using both planar and tomographic optical imaging methods. An αvβ3-targeted RGD peptide was labelled with a cyanine dye (Cy 5.5). Binding of the optical tracer was tested on M21 melanoma ( n = 5), HT-1080 fibrosarcoma ( n = 6) and MCF-7 adenocarcinoma ( n = 5) cells and their tumour xenografts. All optical imaging studies were performed using two-dimensional planar fluorescence reflectance imaging (FRI) technology and three-dimensional fluorescence-mediated tomography (FMT). In vitro, the peptide-dye conjugate showed a clear binding affinity to αvβ3-positive M21 and HT-1080 cells while αvβ3-negative MCF-7 cells and pre-dosing with the free RGD peptide revealed little to no fluorescence. In vivo, tumour xenografts were clearly visualised by FRI and FMT up to 24 h post injection. FMT allowed quantification of the fluorochrome distribution in deeper tissue sections showing an average fluorochrome concentration of 417.61 ± 105.82 n M Cy 5.5 (M21), 353.68 ± 54.02 n M Cy 5.5 (HT-1080) and 262.83 ± 155.36 n M Cy 5.5 (MCF-7) in the target tissue 60 min after tracer administration. Competition with the free RGD peptide resulted in a reduction in the fluorochrome concentration in M21 tumour tissue (294.35 ± 84.27 n M). RGD-Cy 5.5 combined with novel tomographic optical imaging methods allows non-invasive imaging of tumour-associated αvβ3 expression and may thus be a promising strategy for sensitive evaluation of tumour target expression. [ABSTRACT FROM AUTHOR]

The purpose of this study was to validate a computerised psychometric test system by demonstrating the change of the test variables of the Bochum Diagnostic System after administration of alcohol. Twenty-four healthy young male or female volunteers participated in a double-blind, randomised, placebo-controlled study in a 3-way cross-over design. The volunteers took single doses of placebo, 0.4 and 0.7 g alcohol/kg body weight (females: 10 % less) in a random sequence. Psychometric tests were performed before as well as 1 and 3 h after the administration of alcohol. The effects of alcohol on the psychometric performance were most pronounced 1 h after administration. At this time a significant dose-dependent impairment of performance in the concentration test, the simple and complex reaction tests, the vigilance test and the coordination test was observed. 3 h after administration, significant effects were only observed in the complex reaction test and the concentration test. Maximal alcohol serum concentrations of 0.47 ± 0.05‰ and of 0.90 ± 0.15‰ were reached after administration of 0.4 g/kg and 0.7 g/kg, respectively. The correlations between individual serum alcohol concentrations and differences of psychometric variables from baseline were significant. It is concluded that the tests of the Bochum Diagnostic System can quantitatively measure the effects of alcohol. The most sensitive tests are the complex reaction test and the concentration test. [ABSTRACT FROM AUTHOR]

The purpose of this study was to validate a computerised psychometric test system by demonstrating the change of the test variables of the Bochum Diagnostic System after administration of alcohol. Twenty-four healthy young male or female volunteers participated in a doubleblind, randomised, placebo-controlled study in a 3-way cross-over design. The volunteers took single doses of placebo, 0.4 and 0.7 g alcohol/kg body weight (females: 10% less) in a random sequence. Psychometric tests were performed before as well as 1 and 3 h after the administration of alcohol. The effects of alcohol on the psychometric performance were most pronounced 1 h after administration. At this time a significant dose-dependent impairment of performance in the concentration test, the simple and complex reaction tests, the vigilance test and the coordination test was observed. 3 h after administration, significant effects were only observed in the complex reaction test and the concentration test. Maximal alcohol serum concentrations of 0.47 +/- 0.05 % per thousand and of 0.90 +/- 0.15 % per thousand were reached after administration of 0.4 g/kg and 0.7 g/kg, respectively. The correlations between individual serum alcohol concentrations and differences of psychometric variables from baseline were significant. It is concluded that the tests of the Bochum Diagnostic System can quantitatively measure the effects of alcohol. The most sensitive tests are the complex reaction test and the concentration test.

The chimeric bcr-abl tyrosine kinase is of crucial pathogenic importance in chronic myeloid leukemia (CML). As shown, bcr-abl activates the ras pathway by phosphorylation of adapter proteins such as Grb-2 and Crkl. Functional inhibition of p21ras might partially inhibit the mitogenic signaling by bcr-abl. By depletion of cellular mevalonate pools, p21ras proteins can be rendered non-functional as a result of deficient post-translational protein farnesylation. We investigated the pharmacologic effect of mevalonate depletion by lovastatin in conjunction with interferon-alpha 2b (INF-alpha 2b) in bcr-abl positive K562 cells. At various concentrations, both drugs synergistically reduced cell proliferation of CML line K562 in a liquid culture system as well as clonal growth of colony forming units in a patient with newly diagnosed CML. Lovastatin and IFN-alpha 2b in combination led to cell cycle arrest and resulted in significant reduction of phosphorylation on tyrosine, serine, and threonine protein residues. IFN-alpha 2b alone showed little effect on protein phosphorylation but strongly enhanced lovastatin driven loss of phosphorylation. Subsequently, DNA fragmentation occurred in 50% of cells. In conclusion, exposure to IFN-alpha 2b and lovastatin synergistically inhibited proliferation of bcr-abl positive cells and resulted in loss of protein phosphorylation and subsequent apoptosis in K562 cells. Our in vitro model suggests further investigations are required of the potential value of HMG-CoA reductase inhibitors as adjunct to therapy of CML with interferon.

Malignant peripheral nerve tumours (MPNT), e.g. malignant schwannoma, represent a relatively rare tumour entity which is usually regarded as a member of the group of soft-tissue sarcomas and treated accordingly. For chemotherapeutic approaches in metastasised disease, ifosfamide and doxorubicin have been identified as the most efficient agents, with overall response rates distinctly less than 50%. In case of non-response, recommendations for effective second-line regimens are lacking. We present the case histories of two patients with pulmonary metastasised MPNT that was primarily refractory to ifosfamide/doxorubicin. Both patients developed a partial remission with tumour reduction exceeding 50% after treatment with carboplatin in combination with etoposide (CE), 150 mg/m2 each, days 1-4 in 4-week intervals. Complete resectability of lung metastases could be achieved, with histologic evidence for advanced tumour regression at the time of resection. Patients remain in stable complete remission 20 and 28 months after surgery, respectively. Major CE-associated toxicity was cumulative myelosuppression, especially thrombocytopenia, reaching WHO grade 4. To our knowledge, this is the first report showing that CE is a possibly successful chemotherapeutic regimen in advanced MPNT, although further studies are necessary to evaluate its efficacy.