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The authors discuss the methods of displaying microarrays of genes to observe forms of expression. They explain a technique whereby additional information can be gathered by adding in the use of laser capture microdissection.

Abstract Background MicroRNAs (MiRNAs) are short non-coding RNAs that control protein expression through various mechanisms. Their altered expression has been shown to be associated with various cancers. The aim of this study was to profile miRNA expression in colorectal cancer (CRC) and to analyze the function of specific miRNAs in CRC cells. MirVana miRNA Bioarrays were used to determine the miRNA expression profile in eight CRC cell line models, 45 human CRC samples of different stages, and four matched normal colon tissue samples. SW620 CRC cells were stably transduced with miR-143 or miR-145 expression vectors and analyzed in vitro for cell proliferation, cell differentiation and anchorage-independent growth. Signalling pathways associated with differentially expressed miRNAs were identified using a gene set enrichment analysis. Results The expression analysis of clinical CRC samples identified 37 miRNAs that were differentially expressed between CRC and normal tissue. Furthermore, several of these miRNAs were associated with CRC tumor progression including loss of miR-133a and gain of miR-224. We identified 11 common miRNAs that were differentially expressed between normal colon and CRC in both the cell line models and clinical samples. In vitro functional studies indicated that miR-143 and miR-145 appear to function in opposing manners to either inhibit or augment cell proliferation in a metastatic CRC model. The pathways targeted by miR-143 and miR-145 showed no significant overlap. Furthermore, gene expression analysis of metastatic versus non-metastatic isogenic cell lines indicated that miR-145 targets involved in cell cycle and neuregulin pathways were significantly down-regulated in the metastatic context. Conclusion MiRNAs showing altered expression at different stages of CRC could be targets for CRC therapies and be further developed as potential diagnostic and prognostic analytes. The identified biological processes and signalling pathways collectively targeted by co-expressed miRNAs in CRC provide a basis for understanding the functional role of miRNAs in cancer.

Commercialization processes are modeled and analyzed from the point of view of the implementation of activities under particular stages. These issues are the subject of many studies and analyzes, which is why the extensive literature is available on this subject. Technology valuation at various stages of the commercialization process is a separate issue. Such valuation is prepared in most cases by consulting companies for determining the price in the buying and selling processes. These valuations use known methods also used in other cases, e.g., real estate valuation. The work carried out presents the author's concept of the commercialization process model, taking into account the costs and value of the technology at various stages of the product life cycle. The model uses a stochastic approach to determine future revenues and costs, which allows estimating the value of the technology by or in determining the probability of assessment validity. The proposed stochastic approach greatly increases the chances of using the presented solutions in practical activities related to technology valuation for the purposes of purchase and sale transactions. [ABSTRACT FROM AUTHOR]

Nowadays, the human is surrounded by numerous things from small simple parts to sophisticated cars, ships, gigantic constructions. More sophisticated parts are composed of simple parts and there are various joining technologies of materials used either by way of dismountable or mountable joints. One of the possibilities of joining various parts together is soldering. High-quality joint is possible to ensure by carrying out quality control. This article is focused on the issue of carrying out quality control in soldering. The introductory part of the article describes the basic problems of the area of solder connections with consequent characteristic of nondestructive quality control - visual inspection. The second part of the article is focused on description of the Burst test of high-pressure oil cooler that was carried out in the practice. The final part of the article provides global evaluation of this test. [ABSTRACT FROM AUTHOR]

Functional alterations in striatal projection neurons play a critical role in the development of motor symptoms in Parkinson's disease (PD), but their molecular adaptation to dopamine depletion remains poorly understood. In particular, type and extent of regulation in postsynaptic signal transduction pathways that determine the responsiveness of striatal projection neurons to incoming stimuli, are currently unknown. Using cell-type-specific transcriptome analyses in a rodent model of chronic dopamine depletion, we identified large-scale gene expression changes, including neurotransmitter receptors, signal transduction cascades, and target proteins of dopamine signaling in striatonigral and striatopallidal neurons. Within the dopamine- and cAMP-regulated phosphoprotein of 32 kDa (DARPP-32) cascade of enzymes that plays a central role in signal integration of dopaminoceptive neurons multiple catalytic and regulatory subunits change their mRNA expression levels. In addition to the number of genes the fact that the alterations occur at multiple levels stresses the biological relevance of transcriptional regulation for adaptations of postsynaptic signaling pathways. The overall pattern of changes in both striatonigral and striatopallidal neurons is compatible with homeostatic mechanisms. In accordance with the distinct biological effects of dopamine D1 and D2 receptor stimulation, the alterations of the transcriptional profiles most likely result in prodopaminergic phosphorylation patterns. Our data provide insight into the disease-related plasticity of functional genomic networks in vivo that might contribute to the protracted preclinical phase of PD. In addition, the data have potential implications for the symptomatic treatment of the disease. [ABSTRACT FROM AUTHOR]

DNA microarrays provide a global view of the physiological state of the cell by parallel analysis of the expression levels of all the genes in an organism. The effects of four bactericidal agents on the expression pattern of Escherichia coli MG1655 were assessed. Compounds were chosen on the basis of their different mechanisms of action and included inhibitors of DNA replication and recombination, translation, transcription and cell wall biosynthesis. The addition of rifampin resulted in increased expression of the target, rpoB, as well as several genes involved in nucleotide salvage and purine biosynthesis. The addition of ampicillin resulted in overall changes in gene expression that showed some similarity to changes induced by rifampin. The addition of the antibiotics kanamycin or norfloxacin resulted in the induction of unique gene expression signatures: a heat shock response to kanamycin and an SOS response to norfloxacin. Several genes of unknown function showed expression profiles similar to the genes associated with the SOS or the heat shock response. Thus, these profiles define families of genes with similar expression phenotypes that can be tested for related function.Copyright © 2003 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Erythropoietin (EPO) is the primary modulator of red blood cell production. Recently EPO has received considerable attention for its functions outside of hematopoiesis, including its effects in the nervous system where it has been shown to act as a neuroprotectant. To understand the function of EPO in the nervous system and to determine if EPO functions through the same signaling pathways identified in hematopoietic cells, we used cDNA array hybridization and RT-PCR to investigate the changes in gene expression induced by EPO in the neuronal-like PC-12 cell line. PC-12 cells cultured in the presence of EPO (10 U/ml) showed significant changes in gene expression by 3 h with a return to basal expression levels for the vast majority of genes by 24 h. The genes influenced by EPO included genes with known functions in cell proliferation, differentiation and apoptosis. Semi-quantitative RT-PCR confirmed that 24 h pre-treatment with EPO (10 pM) resulted in a 2.5-fold increase in the expression of the anti-apoptotic gene bclXL and a 4-fold decrease in the expression of the pro-apoptotic gene bak. In addition to supporting the current models of EPO function these results suggest previously unidentified mechanisms by which EPO may function in neurons. [Copyright &y& Elsevier]

Generating gene-expression profiles from laser-captured cells requires the successful combination of laser-capture microdissection, RNA extraction, RNA amplification, and microarray analysis. To permit single-cell gene-expression profiling, the RNA amplification method has to be sufficiently powerful to bridge the gap between the amount of RNA available from a single cell to what is required by the microarray, a gap that spans 5 to 6 orders of magnitude. This chapter focuses on the amplification of RNA using a two-round T7 RNA amplification method. The protocols described are adapted for laser-captured material and have been used to generate gene expression profiles from single laser-captured cells.