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Clelia Peano

Publications and source records attributed to Clelia Peano.

3 recordsLinked to original sources

Strategies for comparing gene expression profiles from different microarray platforms: application to a case-control experiment.

Meta-analysis of microarray data is increasingly important, considering both the availability of multiple platforms using disparate technologies and the accumulation in public repositories of data sets from different laboratories. We addressed the issue of comparing gene expression profiles from two microarray platforms by devising a standardized investigative strategy. We tested this procedure by studying MDA-MB-231 cells, which undergo apoptosis on treatment with resveratrol. Gene expression profiles were obtained using high-density, short-oligonucleotide, single-color microarray platforms: GeneChip (Affymetrix) and CodeLink (Amersham). Interplatform analyses were carried out on 8414 common transcripts represented on both platforms, as identified by LocusLink ID, representing 70.8% and 88.6% of annotated GeneChip and CodeLink features, respectively. We identified 105 differentially expressed genes (DEGs) on CodeLink and 42 DEGs on GeneChip. Among them, only 9 DEGs were commonly identified by both platforms. Multiple analyses (BLAST alignment of probes with target sequences, gene ontology, literature mining, and quantitative real-time PCR) permitted us to investigate the factors contributing to the generation of platform-dependent results in single-color microarray experiments. An effective approach to cross-platform comparison involves microarrays of similar technologies, samples prepared by identical methods, and a standardized battery of bioinformatic and statistical analyses.

Breast Neoplasms↗

Transcriptome amplification methods in gene expression profiling.

The increasing use of microarray expression profiling to study the molecular biology of cancer and the cellular physiology of difficult-to-isolate cell types has led to a need for methods that accurately and precisely amplify small quantities of RNA. The purpose of this review is to provide an overview of the existing methods for transcriptome amplification and to define the parameters for comparing different amplification methods. The authors propose a standardized protocol for the assessment and evaluation of amplification methods, focusing on a new whole-transcriptome amplification kit, which amplifies total RNA into cDNA fragments. Reproducibility and reliability of the method were analyzed and discussed using both quantitative real-time PCR and a high-density oligonucleotide microarray platform.

DNA, Complementary↗

Qualitative and quantitative evaluation of the genomic DNA extracted from GMO and non-GMO foodstuffs with four different extraction methods.

The presence of DNA in foodstuffs derived from or containing genetically modified organisms (GMO) is the basic requirement for labeling of GMO foods in Council Directive 2001/18/CE (Off. J. Eur. Communities 2001, L1 06/2). In this work, four different methods for DNA extraction were evaluated and compared. To rank the different methods, the quality and quantity of DNA extracted from standards, containing known percentages of GMO material and from different food products, were considered. The food products analyzed derived from both soybean and maize and were chosen on the basis of the mechanical, technological, and chemical treatment they had been subjected to during processing. Degree of DNA degradation at various stages of food production was evaluated through the amplification of different DNA fragments belonging to the endogenous genes of both maize and soybean. Genomic DNA was extracted from Roundup Ready soybean and maize MON810 standard flours, according to four different methods, and quantified by real-time Polymerase Chain Reaction (PCR), with the aim of determining the influence of the extraction methods on the DNA quantification through real-time PCR.

DNA↗