Early responses to chemotherapy detected by pulse cytophotometry.

DNA/cell distributions were recorded by automated cytofluorometry (=pulse cytophotometry) in bone-marrow aspirates of leukaemia and lymphosarcoma patients subjected to chemotherapy. In most cases, early perturbations in DNA/cell histographs were observed, characteristically reflecting the known mode of action of the drugs. These changes in general preceded the clinical observation of drug response. In a series of 23 measurements in 19 patients, a positive correlation between early cytophotometric changes and clinical effects of chemotherapy was observed in 17 patients. Five patients were negative for both cytophotometric and clinical reactions and one patient was probably false-positive. The validity of the assay for early detection of drug resistance in acute leukaemia and related diseases is discussed

The effect of gastrectomy on regorafenib exposure and progression-free survival in patients with advanced gastrointestinal stromal tumours

Contains fulltext : 208932.pdf (publisher's version ) (Open Access)AIMS: We investigated whether major gastrectomy influences the plasma exposure of regorafenib and treatment outcome. METHODS: Efficacy and pharmacokinetic data from 133 gastrointestinal stromal tumour patients included in a phase III trial were analysed. Patients were subdivided into 2 groups according to the extent of the gastrectomy (no/nonsignificant gastrectomy and major gastrectomy). Progression-free survival (PFS) on regorafenib was measured and regorafenib and its pharmacological active metabolites plasma exposure were measured. RESULTS: A total of 133 patient were included, of whom 27 underwent major gastrectomy. In patients with no/nonsignificant gastrectomy the median PFS was 145 (interquartile range 43-281) days. The PFS in patients with a major gastrectomy was 172 (interquartile range 57-280) days. Regorafenib pharmacokinetic samples were collected in 80 patients of which 19 patients with a major gastrectomy and 61 patients with no/nonsignificant gastric surgery. The average +/- standard deviation total concentration of regorafenib including the metabolites M-2 and M-5 was 6.9 +/- 1.53 mumol/L and 6.7 +/- 1.56 mumol/L in patient with major gastrectomy and no/nonsignificant gastrectomy respectively. CONCLUSION: Our study shows that major gastrectomy did not influence plasma exposure of regorafenib and metabolites. In addition, no difference in PFS between the subgroups was seen

Energy-Filtering Transmission Electron Microscopy as a Tool for Structural and Compositional Analysis of Isolated Ferritin Particles

Structural and compositional analysis of isolated horse-spleen ferritin particles was performed by energy filtering transmission electron microscopy (EFTEM). Ferritin particles were collected in ultrathin (2 nm thick) chromium films and analyzed without any additional stain by electron energy-loss spectroscopy (EELS) for iron and carbon and by electron-spectroscopic imaging (ESI) for carbon. The ultrastructure of the proteinaceous shell of the ferritin particle, as obtained by the carbon net-intensity electron spectroscopical and carbon concentration-distribution images, was qualitatively compared to the structure as acquired by a negative-staining procedure. Quantitative analysis of the number of carbon atoms in the ferritin-shell proteins was carried out through an ESI-acquisition protocol and processing procedure with calibrated attenuation filters in the optical path to the TV camera. This procedure included images acquired with calibrated attenuation filters for the compensation of shading and the non-linear performance of the TV camera used in the analytical part of the procedure. A new ESI-Spectra program is proposed that allows element-related spectra to be generated at any place and with any frame size in a contrast-sensitive or other type of image present on the computer monitor screen

Evaluation of high-resolution microarray platforms for genomic profiling of bone tumours

<p>Abstract</p> <p>Background</p> <p>Several high-density oligonucleotide microarray platforms are available for genome-wide single nucleotide polymorphism (SNP) detection and microarray-based comparative genomic hybridisation (array CGH), which may be used to detect copy number aberrations in human tumours. As part of the EuroBoNeT network of excellence for research on bone tumours (eurobonet.eu), we have evaluated four different commercial high-resolution microarray platforms in order to identify the most appropriate technology for mapping DNA copy number aberrations in such tumours.</p> <p>Findings</p> <p>DNA from two different cytogenetically well-characterized bone sarcoma cell lines, representing a simple and a complex karyotype, respectively, was tested in duplicate on four high-resolution microarray platforms; Affymetrix Genome-Wide Human SNP Array 6.0, Agilent Human Genome CGH 244A, Illumina HumanExon510s-duo and Nimblegen HG18 CGH 385 k WG tiling v1.0. The data was analysed using the platform-specific analysis software, as well as a platform-independent analysis algorithm. DNA copy number was measured at six specific chromosomes or chromosomal regions, and compared with the expected ratio based on available cytogenetic information. All platforms performed well in terms of reproducibility and were able to delimit and score small amplifications and deletions at similar resolution, but Agilent microarrays showed better linearity and dynamic range. The platform-specific analysis software provided with each platform identified in general correct copy numbers, whereas using a platform-independent analysis algorithm, correct copy numbers were determined mainly for Agilent and Affymetrix microarrays.</p> <p>Conclusions</p> <p>All platforms performed reasonably well, but Agilent microarrays showed better dynamic range, and like Affymetrix microarrays performed well with the platform-independent analysis software, implying more robust data. Bone tumours like osteosarcomas are heterogeneous tumours with complex karyotypes that may be difficult to interpret, and it is of importance to be able to well separate the copy number levels and detect copy number changes in subpopulations. Taking all this into consideration, the Agilent and Affymetrix microarray platforms were found to be a better choice for mapping DNA copy numbers in bone tumours, the latter having the advantage of also providing heterozygosity information.</p

Syndromic approach to arboviral diagnostics for global travelers as a basis for infectious disease surveillance

Background Arboviruses have overlapping geographical distributions and can cause symptoms that coincide with more common infections. Therefore, arbovirus infections are often neglected by travel diagnostics. Here, we assessed the potential of syndrome-based approaches for diagnosis and surveillance of neglected arboviral diseases in returning travelers. Method To map the patients high at risk of missed clinical arboviral infections we compared the quantity of all arboviral diagnostic requests by physicians in the Netherlands, from 2009 through 2013, with a literature-based assessment of the travelers’ likely exposure to an arbovirus. Results 2153 patients, with travel and clinical history were evaluated. The diagnostic assay for dengue virus (DENV) was the most commonly requested (86%). Of travelers returning from Southeast Asia with symptoms compatible with chikungunya virus (CHIKV), only 55% were tested. For travelers in Europe, arbovirus diagnostics were rarely requested. Over all, diagnostics for most arboviruses were requested only on severe clinical presentation. Conclusion Travel destination and syndrome were used inconsistently for triage of diagnostics, likely resulting in vast under-diagnosis of arboviral infections of public health significance. This study shows the need for more awareness among physicians and standardization of syndromic diagnostic algorithm

MLPAinter for MLPA interpretation: An integrated approach for the analysis, visualisation and data management of Multiplex Ligation-dependent Probe Amplification

Background: Multiplex Ligation-Dependent Probe Amplification (MLPA) is an application that can be used for the detection of multiple chromosomal aberrations in a single experiment. In one reaction, up to 50 different genomic sequences can be analysed. For a reliable work-flow, tools are needed for administrative support, data management, normalisation, visualisation, reporting and interpretation.Results: Here, we developed a data management system, MLPAInter for MLPA interpretation, that is windows executable and has a stand-alone database for monitoring and interpreting the MLPA data stream that is generated from the experimental setup to analysis, quality control and visualisation. A statistical approach is applied for the normalisation and analysis of large series of MLPA traces, making use of multiple control samples and internal controls.Conclusions: MLPAinter visualises MLPA data in plots with information about sample replicates, normalisation settings, and sample characteristics. This integrated approach helps in the automated handling of large series of MLPA data and guarantees a quick and streamlined dataflow from the beginning of an experiment to an authorised report

Genetic alterations on chromosome 16 and 17 are important features of ductal carcinoma in situ of the breast and are associated with histologic type

We analysed the involvement of known and putative tumour suppressor- and oncogene loci in ductal carcinoma in situ (DCIS) by microsatellite analysis (LOH), Southern blotting and comparative genomic hybridization (CGH). A total of 78 pure DCIS cases, classified histologically as well, intermediately and poorly differentiated, were examined for LOH with 76 markers dispersed along all chromosome arms. LOH on chromosome 17 was more frequent in poorly differentiated DCIS (70%) compared to well-differentiated DCIS (17%), whereas loss on chromosome 16 was associated with well- and intermediately differentiated DCIS (66%). For a subset we have done Southern blot- and CGH analysis. C-erbB2/neu was amplified in 30% of poorly differentiated DCIS. No amplification was found of c-myc, mdm2, bek, flg and the epidermal growth factor (EGF)-receptor. By CGH, most frequent alterations in poorly differentiated DCIS were gains on 8q and 17q22–24 and deletion on 17p, whereas in well-differentiated DCIS amplification on chromosome 1q and deletion on 16q were found. In conclusion, our data indicates that inactivation of a yet unknown tumour suppressor gene on chromosome 16q is implicated in the development of most well and intermediately differentiated DCIS whereas amplification and inactivation of various genes on chromosome 17 are implicated in the development of poorly differentiated DCIS. Furthermore these data show that there is a genetic basis for the classification of DCIS in a well and poorly differentiated type and support the evidence of different genetic routes to develop a specific type of carcinoma in situ of the breast. © 1999 Cancer Research Campaig