In this work we illustrate the approach of the Maastricht Brain Imaging Center to the PBAIC 2007 competition, where participants had to predict, based on fMRI measurements of brain activity, subject driven actions and sensory experience in a virtual world. After standard pre-processing (slice scan time correction, motion correction), we generated rating predictions based on linear Relevance Vector Machine (RVM) learning from all brain voxels. Spatial and temporal filtering of the time series was optimized rating by rating.
View Article and Find Full Text PDFThe pathogenicity of Mycobacterium ulcerans (Buruli ulcer) depends on cytotoxic effect of its exotoxin mycolactone. Since epidermis represents a barrier against infectious agents and balanced apoptosis is essential in epidermal homeostasis, we explored if mycolactone A/B induces apoptosis on two human keratinocyte populations, stem cells (KSC) and transit amplifying cells (TAC), and on human keratinocyte line, HaCaT. Treatment of TAC with 1 and 10 ng/ml mycolactone-induced 60 and 90% apoptosis.
View Article and Find Full Text PDFThe combination of electroencephalography (EEG) and functional Magnetic Resonance Imaging (fMRI) has been proposed as a tool to study brain dynamics with both high temporal and high spatial resolution. Integration through EEG-fMRI trial-by-trial coupling has been proposed as a method to combine the different data sets and achieve temporal expansion of the fMRI data (Eichele et al., 2005).
View Article and Find Full Text PDFBackground: Metastatic carcinomas to the pituitary gland are uncommon, occurring in only 1% of the pituitary masses. They often originate from breast or lung carcinomas and may resemble a nonfunctioning pituitary adenoma both clinically and radiologically. Here we describe a patient with pituitary metastasis from follicular thyroid carcinoma and discuss the unique features of these lesions.
View Article and Find Full Text PDFMonoclonal components (MC) formed by chains/fragments of intact/truncated globulin components produced in different lymphoproliferative diseases are responsible for monoclonal immunoglobulin deposition disease (MIDD) and consequent tissue damage by organized (amyloid fibrils) or non-organized (amorphous) deposits. The kidneys are the most commonly affected organs in MIDD, and renal failure represents an important adverse factor for prognosis. The renal outcome and the role of renal pathology in diagnosing MIDD was evaluated in 289 elderly patients with multiple myeloma (MM, n=115) and monoclonal gammopathy (MGUS, n=174).
View Article and Find Full Text PDFThe lysosomal protease Cathepsin D (CD) has been implicated in the homeostasis of lymphatic tissues. We investigated whether the level of CD expression influences the progression and the clinical outcome in Non-Hodgkin's Lymphomas (NHLs). The expression of CD was assessed by immunohistochemistry and immunofluorescence in biopsies of Diffuse Large B Cell Lymphomas (DLBCL, 35 cases), Follicular Lymphomas (FL, 9 cases of grade I-II plus 14 cases of grade IIIB), Chronic Lymphocytic Leukaemias (CLL, 17 cases) and Peripheral T-cell Lymphomas (PTCL, 5 cases).
View Article and Find Full Text PDFThe expression of beclin-1, an oncosuppressor monoallelically deleted in >60% epithelial cancers, has been shown to be developmentally regulated in T and B lymphocytes. By interacting with either bcl-2 or class III phosphatidyl-inositol-3-phosphate kinase, beclin-1 regulates apoptosis and autophagy, two processes crucial for lymphatic tissue homeostasis. We analyzed the potential link between beclin-1-mediated autophagy and the malignant behaviour of lymphomas.
View Article and Find Full Text PDFThree species of cichlids belonging to the genus Symphysodon have demonstrated interspecific and intraspecific variation in nucleolus organizer regions (NOR) detected with silver nitrate. In order to understand the evolution of this marker in the genus, the structural variability of these sequences in mitotic chromosomes from Symphysodon aequifasciatus, Symphysodon discus and Symphysodon haraldi was investigated using both silver nitrate impregnation and hybridization of the 18S rRNA gene probe. For the three species, the two markers were intraspecifically and interspecifically variable both in the number and in the size of the sites.
View Article and Find Full Text PDFPurpose: Powerful mediators of programmed cell death, such as apoptosis and autophagy, can contribute to myocyte cell loss during pathological cardiac conditions. Levosimendan has been shown to exert beneficial hemodynamic effects in presence of global myocardial ischemia and heart failure through vasodilatation and increase of cardiac contractility. Recently, the intracoronary administration of a bolus levosimendan was found to exert favourable cardiac anti-stunning effects without lowering arterial pressure, which limits the use of levosimendan mainly in coronary artery disease.
View Article and Find Full Text PDFAs part of a genetic screening program for wild Discus fishes, we analyzed karyotypes and cytogenetic characteristics of Symphysodon aequifasciatus, S. discus and S. haraldi using C-banding and fluorescent in situ hybridization (FISH) with the Rex3 retrotransposon and 5S rDNA probes in mitotic and meiotic chromosomes.
View Article and Find Full Text PDFThe combination of electroencephalography (EEG) and functional magnetic resonance imaging (fMRI) has been proposed as a tool to study brain dynamics with both high temporal and high spatial resolution. Multimodal imaging techniques rely on the assumption of a common neuronal source for the different recorded signals. In order to maximally exploit the combination of these techniques, one needs to understand the coupling (i.
View Article and Find Full Text PDFBackground: Plex-B1, the receptor of Sema4D, has been implicated in tumour growth, angiogenesis and metastasis. The binding of Sema4D to Plex-B1 can trigger the activation of Met tyrosine kinase, thereby promoting cell dissociation and invasive growth. We tested the hypothesis that the expression of Plex-B1, either alone or in association with Met, can be of predictive value for tumour progression.
View Article and Find Full Text PDFIn order to improve the dispersion of single-wall carbon nanotubes in a matrix of poly(3-hexylthiophene), this paper reports the modification of single-wall carbon nanotubes with COOH groups followed by reaction with cysteamine that introduced thiol groups along the tubes. The resulting modified single-wall carbon nanotubes were characterized by high resolution transmission electron microscopy, thermogravimetric analysis, X-ray photoelectron spectroscopy and Raman spectroscopy. The modified carbon nanotubes were applied, in combination with poly(3-hexylthiophene), in a bulk heterojunction solar cell.
View Article and Find Full Text PDFRepeated DNA elements have been extensively applied as physical chromosome markers in comparative studies for the identification of chromosomal rearrangements, the identification of sex chromosomes, chromosome evolution analysis and applied genetics. Here, we report the characterization of the transposable elements (TE) Tc1, Rex1, Rex3 and Rex6 and a new element called RCk in the genome of the South American cichlid fish Cichla kelberi using nucleotide sequence analysis and hybridization to metaphase chromosomes. The analysis of the repeated elements demonstrated that they are, in most cases, compartmentalized in heterochromatic regions, as has been observed in several other vertebrates.
View Article and Find Full Text PDFDarier disease (DD) is a relatively common genodermatosis characterized by impaired differentiation and abnormal cell-to-cell adhesion. Haploinsufficiency of the ATP2A2 gene product, sarco/endoplasmic reticulum Ca(2+) ATPase isoform 2 (SERCA2), is the underlying cause of most cases. Although DD may have a papillomatous appearance, few and controversial results have been reported about the role of human papillomavirus (HPV) in this disease.
View Article and Find Full Text PDFEur Rev Med Pharmacol Sci
August 2009
Background: The mammalian target of rapamycin (mTOR) controls cell growth through protein synthesis regulation. It can be activated by protein kinase B (AKT) or through ribosomal S6 kinase (S6K1). In malignant glioma, mTOR inhibitors have antiproliferative and proapoptotic effects and mTOR has been suggested as a target of therapies, thus it is worthwhile to verify its relations with the phosphatidylinositol-3-kinase (PI3)/AKT cascade, proliferation and apoptosis in human gliomas.
View Article and Find Full Text PDFSpatial independent component analysis (ICA) is a well-established technique for multivariate analysis of functional magnetic resonance imaging (fMRI) data. It blindly extracts spatiotemporal patterns of neural activity from functional measurements by seeking for sources that are maximally independent. Additional information on one or more sources (e.
View Article and Find Full Text PDFObjectives: In spite of aggressive surgery and high-dose radiotherapy, the long-term survival of patients with sinonasal cancer remains disappointing. In this paper, we report data from 179 consecutive cases treated in the Italian Piedmont region between 1996 and 2000 according to a fixed protocol.
Methods: Clinical and pathological data and the following biological parameters were analyzed: microvessel density and growth fraction by CD31 and Ki-67 positivity, respectively, and immunohistochemical expression of vascular endothelial growth factor (VEGF).
Speech and vocal sounds are at the core of human communication. Cortical processing of these sounds critically depends on behavioral demands. However, the neurocomputational mechanisms enabling this adaptive processing remain elusive.
View Article and Find Full Text PDFThe c-MET proto-oncogene, encoding the p190 hepatocyte growth factor tyrosine kinase receptor, can acquire oncogenic potential by multiple mechanisms, such as gene rearrangement, amplification and overexpression, point mutation, and ectopic expression, all resulting in its constitutive activation. Hepatocyte growth factor receptor truncated forms are generated by post-translational cleavage: p140 and p130 lack the kinase domain and are inactive. Their C-terminal remnant fragments are generally undetectable in normal cells, but a membrane-associated truncated form is recognized by anti-C-terminus antibodies in some human tumors, suggesting that a hepatocyte growth factor receptor lacking the ectodomain, but retaining the transmembrane and intracellular domains (Met-EC-), could acquire oncogenic properties.
View Article and Find Full Text PDFIn functional brain mapping, pattern recognition methods allow detecting multivoxel patterns of brain activation which are informative with respect to a subject's perceptual or cognitive state. The sensitivity of these methods, however, is greatly reduced when the proportion of voxels that convey the discriminative information is small compared to the total number of measured voxels. To reduce this dimensionality problem, previous studies employed univariate voxel selection or region-of-interest-based strategies as a preceding step to the application of machine learning algorithms.
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