RNA Amplification (rna + amplification)

Distribution by Scientific Domains


Selected Abstracts


Laser capture microdissection and microarray analysis of dividing neural progenitor cells from the adult rat hippocampus

EUROPEAN JOURNAL OF NEUROSCIENCE, Issue 5 2007
Ulf Gurok
Abstract Neural progenitor cells reside in the hippocampus of adult rodents and humans and generate granule neurons throughout life. Knowledge about the molecular processes regulating these neurogenic cells is fragmentary. In order to identify genes with a role in the proliferation of adult neural progenitor cells, a protocol was elaborated to enable the staining and isolation of such cells under RNA-preserving conditions with a combination of immunohistochemistry and laser capture microdissection. We increased proliferation of neural progenitor cells by electroconvulsive treatment, one of the most effective antidepressant treatments, and isolated Ki-67-positive cells using this new protocol. RNA amplification via in vitro transcription and subsequent microarray analysis revealed over 100 genes that were differentially expressed in neural progenitor cells due to electroconvulsive treatment compared to untreated control animals. Some of these genes have already been implicated in the functioning of neural progenitor cells or have been induced by electroconvulsive treatment; these include brain-derived neurotrophic factor (Bdnf), PDZ-binding kinase (Pbk) and abnormal spindle-like microcephaly-associated (Aspm). In addition, genes were identified for which no role in the proliferation of neurogenic progenitors has been described so far, such as enhancer of zeste homolog 2 (Ezh2). [source]


Transcriptional profiling using a novel cDNA array identifies differential gene expression during porcine embryo elongation

MOLECULAR REPRODUCTION & DEVELOPMENT, Issue 2 2005
So Hyun Lee
Abstract A novel porcine cDNA array, containing 1,015 PCR products selected for embryonic expression, was used for transcriptional profiling of conceptuses at four stages of peri-implantation development. Total conceptus RNA from small spherical, large spherical, tubular, and filamentous stages was amplified, converted to cDNA, and hybridized to membranes. Initially, normalized signal intensities obtained using cDNA from total RNA or from amplified RNA were compared. Uniform distribution of P -values associated with t -tests conducted for each gene indicated no evidence that amplification introduced bias. Analysis of data obtained by using amplified targets and the novel array identified genes differentially expressed across stages. Such genes were identified by testing for significant stage effects in gene-specific mixed models. A total of nine genes were declared differentially expressed. Six of the nine genes had P -values less than 0.001, and a false discovery rate of approximately 17% was associated with this significance threshold. Two out of six genes were significant when using the Bonferroni method to control the probability of one or more false positives. The other three genes had P -values between 0.001 and 0.01 and exhibited differences greater than twofold between stages. All four genes selected for confirmation (steroidogenic acute regulatory protein, interleukin 1 beta, transforming growth factor beta 3, and thymosin beta 10) were shown to be differentially expressed by using quantitative real time RT-PCR. Our study shows that RNA amplification is useful for transcriptional profiling with limiting porcine embryonic RNA, and that this novel targeted array can detect differential gene expression during trophoblastic elongation. Finally, our results contribute to an increased understanding of the temporal patterns of expression of known genes controlling conceptus development, as well as identify novel genes also differentially regulated during implantation. Mol. Reprod. Dev. 71: 129,139, 2005. © 2005 Wiley-Liss, Inc. [source]


Assessment of RNA amplification by multiplex RT-PCR and IgM detection by indirect and capture ELISAs for the diagnosis of measles and rubella

APMIS, Issue 3 2010
JUAN CARLOS SANZ
Sanz JC, Mosquera M, Ramos B, Ramírez R, de Ory F, Echevarria JE. Assessment of RNA amplification by multiplex RT-PCR and IgM detection by indirect and capture ELISAs for the diagnosis of measles and rubella. APMIS 2010; 118: 203,9. The aim of the study was to compare RNA amplification using multiplex RT-PCR and IgM detection by means of indirect and capture ELISAs for the diagnosis of measles and rubella. A total of 229 cases of maculopapular rash with serum and throat swab samples were included. Specific serological IgM to measles and rubella was determined by Enzygnost® (Siemens) and PlateliaTM (Bio-Rad). Both viruses were researched using multiplex RT-PCR performed on throat samples. Criteria for inclusion of measles or rubella cases were a positive RT-PCR result for one virus and negative for the other; and/or a positive IgM result for one virus by both ELISAs and negative RT-PCR for the other virus. A total of 74 cases were classified as measles and 54 as rubella. In measles, sensitivity and specificity were 93.2% and 100% for RT-PCR, 97.3% and 98.1% for Enzygnost®, and 90.5% and 95.5% for PlateliaTM. For rubella, these values were 42.6% and 100% for RT-PCR, 100% and 97.1% for Enzygnost®, and 94.4% and 98.3% for PlateliaTM. Enzygnost® and PlateliaTM are useful techniques for detecting IgM against measles and rubella. RNA amplification by RT-PCR was both sensitive and specific for the diagnosis of measles; however, for rubella, the sensitivity of this technique must be improved. [source]


Subtype-specific peripheral blood gene expression profiles in recent-onset juvenile idiopathic arthritis

ARTHRITIS & RHEUMATISM, Issue 7 2009
Michael G. Barnes
Objective To identify differences in peripheral blood gene expression between patients with different subclasses of juvenile idiopathic arthritis (JIA) and healthy controls in a multicenter study of patients with recent-onset JIA prior to treatment with disease-modifying antirheumatic drugs (DMARDs) or biologic agents. Methods Peripheral blood mononuclear cells (PBMCs) from 59 healthy children and 136 patients with JIA (28 with enthesitis-related arthritis [ERA], 42 with persistent oligoarthritis, 45 with rheumatoid factor [RF],negative polyarthritis, and 21 with systemic disease) were isolated from whole blood. Poly(A) RNA was labeled using a commercial RNA amplification and labeling system (NuGEN Ovation), and gene expression profiles were obtained using commercial expression microarrays (Affymetrix HG-U133 Plus 2.0). Results A total of 9,501 differentially expressed probe sets were identified among the JIA subtypes and controls (by analysis of variance; false discovery rate 5%). Specifically, 193, 1,036, 873, and 7,595 probe sets were different in PBMCs from the controls compared with those from the ERA, persistent oligoarthritis, RF-negative polyarthritis, and systemic JIA patients, respectively. In patients with persistent oligoarthritis, RF-negative polyarthritis, and systemic JIA subtypes, up-regulation of genes associated with interleukin-10 (IL-10) signaling was prominent. A hemoglobin cluster was identified that was underexpressed in ERA patients but overexpressed in systemic JIA patients. The influence of JAK/STAT, ERK/MAPK, IL-2, and B cell receptor signaling pathways was evident in patients with persistent oligoarthritis. In systemic JIA, up-regulation of innate immune pathways, including IL-6, Toll-like receptor/IL-1 receptor, and peroxisome proliferator,activated receptor signaling, were noted, along with down-regulation of gene networks related to natural killer cells and T cells. Complement and coagulation pathways were up-regulated in systemic JIA, with a subset of these genes being differentially expressed in other subtypes as well. Conclusion Expression analysis identified differentially expressed genes in PBMCs obtained early in the disease from patients with different subtypes of JIA and in healthy controls, providing evidence of immunobiologic differences between these forms of childhood arthritis. [source]