225 research outputs found
Comparison of Fluorescein Isothiocyanate-Conjugated and Texas-Red-Conjugated Nucleotides for Direct Labeling in Comparative Genomic Hybridization
Fil: Larramendy, Marcelo Luis. Cátedra de Citología. Facultad de Ciencias Naturales y Museo. Universidad Nacional de La Plata; ArgentinaFil: Elrifai, Wa`el. Department of Medical Genetics. Haartman Institute. University of Helsinki. Helsinki; FinlandFil: Knuutila, Sakari. Laboratory of Medical Genetics. Helsinki University. Central Hospital. Helsinki; Finlan
Dependency detection with similarity constraints
Unsupervised two-view learning, or detection of dependencies between two
paired data sets, is typically done by some variant of canonical correlation
analysis (CCA). CCA searches for a linear projection for each view, such that
the correlations between the projections are maximized. The solution is
invariant to any linear transformation of either or both of the views; for
tasks with small sample size such flexibility implies overfitting, which is
even worse for more flexible nonparametric or kernel-based dependency discovery
methods. We develop variants which reduce the degrees of freedom by assuming
constraints on similarity of the projections in the two views. A particular
example is provided by a cancer gene discovery application where chromosomal
distance affects the dependencies between gene copy number and activity levels.
Similarity constraints are shown to improve detection performance of known
cancer genes.Comment: 9 pages, 3 figures. Appeared in proceedings of the 2009 IEEE
International Workshop on Machine Learning for Signal Processing XIX
(MLSP'09). Implementation of the method available at
http://bioconductor.org/packages/devel/bioc/html/pint.htm
Chromosomal in situ suppression hybridization of immunologically classified mitotic cells in hematologic malignancies
Chromosomal in situ suppression (CISS) hybridization was performed with library DNA from sorted human chromosomes 8, 9, 15, 17, 21, and 22 on immunologically stained bone marrow cells of four patients with a hematologic neoplasm, including two patients with myelodysplastic syndrome and trisomy 8, one patient with promyelocytic leukemia bearing the translocation t(15;17)(q22;q11-12), and one patient with chronic myeloid leukemia and the translocation t(9;22)(q34;q11). In all patients, the results of conventional karyotype analysis could be confirmed by one- or two-color CISS hybridization using the appropriate chromosome-specific libraries. Our results show that CISS hybridization can detect both numerical and structural chromosome changes in immunologically classified cells with high specificity and reliability. The fact that chromosome spreads of very poor quality can now be included in such analyses is a decisive advantage of this approach. In addition, the suitability of this approach for interphase cytogenetics is discussed
Hotspot Mutations Detectable by Next-generation Sequencing in Exhaled Breath Condensates from Patients with Lung Cancer
Background: Genetic alterations occurring in lung cancer are the basis for defining molecular subtypes and essential for targeted therapies. Exhaled breath condensate (EBC) is a form of non-invasive sample that, amongst components, contains DNA from pulmonary tissue. Nextgeneration sequencing (NGS) was herein used to analyze mutations in EBC from patients with lung cancer. Materials and Methods: EBC was collected from 26 patients with cancer and 20 healthy controls. Amplicon-based sequencing using Ion Ampliseq Colon and Lung Cancer gene panel v2 was applied. Results: The sequencing was successful in 17 patients and 20 controls. EBC from patients revealed 39 hotspot mutations occurring in: adenomatous polyposis coli (APC), v-raf murine sarcoma viral oncogene homolog B (BRAE), discoidin domain receptor tyrosine kinase 2 (DDR2), epidermal growth factor receptor (EGFR), erb-b2 receptor tyrosine kinase 4 (ERBB4), F-box and WD repeat domain containing 7 (FBXW7), fibroblast growth factor receptor 1 (FGER1), FGFR3 (fibroblast growth factor receptor 3), Kirsten rat sarcoma viral oncogene homolog (KRAS), mitogen-activated protein kinase kinase 1 (MAP2K1), met proto-oncogene (MET), neuroblastoma RAS viral (v-ras) oncogene homolog (NRAS), phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha (PIK3CA), phosphatase and tensin homolog (PTEN), ret proto-oncogene (RET), SMAD family member 4 (SMAD4), serine/threonine kinase 11 (STK11), and tumorprotein p53 (TP53) genes. EBC from controls revealed 35 hotspot mutations. The average mutant allele fraction was higher in patients than controls. Conclusion: NGS can identify mutations in EBCs from patients with lung cancer. This could provide a promising non-invasive method for the assessment of gene mutations in lung cancer.Peer reviewe
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