Dataset Information

Gene expression profile in labouring and non-labouring human placenta near term

ABSTRACT: Sample and RNA preparation: The series is composed of seventeen hybridizations for analysis of differentially expressed genes in placenta tissues from women after vaginal delivery (labouring) and after elective caesarean section (non-labouring). Total RNA extraction was performed by using the MagNa Pure Compact RNA Isolation Kit (Roche Applied Science). Labeling and hybridization: Total RNA was reverse transcribed and labeled with Cy3-attached dendrimer using the Genisphere 3DNA HS kit (Genisphere) as described in the manufacturer’s protocol. Hybridizations were carried out with a TECAN HS4800 instrument using the foramamide-based hybridization buffer from Genisphere containing 5% dextran sulphate and 0.5 microgram COT1 DNA/microgram RNA at 37°C for 23 hours. 3DNA dendrimer hybridizations were carried out in formamide-based hybridization buffer alone. Post-hybridization washes were carried out at room temperature with 2xSSC for 1 min, 0.2% SDS/2xSSC for 1 min and finally with0.2xSSC for 30 sec. Scanning, image analysis and data processing: The microarrays were scanned on an AXON 4000B scanner and images were quantified using GenePix pro 6.0 software. The background estimates were calculated using the morphological opening method. Spots that displayed a signal-to-noise ratio of less than 3 or that were significantly saturated (more than 20 % saturation among foreground pixels) were filtered out. The median was used as the averaging measure of the foreground pixels. After quality control, genes that were present in less than 50 % of the arrays were filtered out. Normalization was carried out using lowess normalization Sample labelling was balanced across the groups, presumably attenuating any dye-effect. For the purpose of finding differentially expressed genes empirical Bayes analysis, using the LIMMA package was applied. The data were analysed using a two-component linear model. The prior guess of the number of D.E genes was set to 0.01. Multiple testing was accounted for by estimating the false discovery rate. We applied the Benjamini-Hochberg procedure, as well as Storeys less conservative Q-value procedure was applied. In none of the cases were any genes significant at a reasonable (15-20% FDR) level. In summary, a 2.5-fold change in expression of any gene that was present on ≥ 8 arrays was considered significant, if the difference in fluorescence intensity between two groups reached a p-value of < 0.01. Keywords: Tissue samples of placenta from women after vaginal delivery (labouring) and after elective caesarean section (non-labouring)

ORGANISM(S): Homo sapiens

PROVIDER: GSE8375 | GEO | 2007/08/01

SECONDARY ACCESSION(S): PRJNA101409

REPOSITORIES: GEO

ACCESS DATA

Dataset's files

Source:

			Action	DRS
		Other

Items per page:

1 - 1 of 1

Similar Datasets

Project description:Gene expression in endometrial cancer cells (Ishikawa) after short time exposure to progestins Sample and RNA preparation: The series is composed of sixteen hybridizations for analysis of differentially expressed genes in endometrial cancer cells (Ishikawa). In eight independent experiments, Ishikawa cells in monolayer received with 30 ug/ml progestin and were grown in RPMI-1640 medium (Sigma, Sty. Louis) with 10% dialyzed foetal calf serum (PAA-laboratories, Austria) without phenol red and antibiotics. Cells were seeded at a density of 1 x 105 cells/ml in 25 cm2 culture flasks in a humidified atmosphere (5% CO2) at 37°C for 4 hours. Cells not treated with progestin served as control groups. Total RNA extraction was performed using TRIZOL Reagent (GIBCO BRL Life Technologies, New York, NY). Labeling and hybridization: Total RNA was reverse transcribed and labeled with Cy3- and Cy5- attached dendrimer, respectively, using the Genisphere 3DNA 350HS kit (Genisphere, Montvale, NJ) as described in the manufacturer's protocol. Hybridizations of transcribed probes were carried out in a TECAN HS4800 instrument using the formamide-based hybridization buffer from Genisphere containing 5% dextrane sulfate and 5.5 ng/ul COT1 DNA (GIBCO BRL Life technologies) at 37º for 23 hours. 3DNA dendrimer hybridizations were carried out in formamide-based hybridization buffer alone. Post-hybridization washes were carried out at room temperature with 2xSSC for 1 min, 0.2% SDS /2xSSC for 1 min and finally with 0.2xSSC for 30 sec. Sixteen hybridizations including dye-swap have been performed for eight independent experiments. Scanning, image analysis and data processing: The arrays were scanned with the GenePix 4000B scanner (Axon Instruments Inc). The features were extracted from the arrays using GenePix Pro 6.0 (Axon instruments Inc., Union City, CA). All subsequent statistical analyses were performed using the statistical package R (R Development Core Team). Spots that displayed a signal-to-noise ratio of less than 2, or that were significantly saturated (more than 20 % saturation among foreground pixels) were filtered out. The median was used as the averaging measure of the foreground pixels. After quality control, genes that were present in less than 50 % of the arrays were filtered out. The arrays were normalized using dye-swap normalization. One array, whose dye swap twin failed was normalized using the lowess method. Statistical significance was assigned to the genes using the SAM methodology. The bioconductor SAMR package was used in the actual analysis. Missing expression levels were imputed using 10 nearest neighbour's imputation. The local FDR threshold was set to 25 %. Keywords: Progestin treatment, Control-treatment

Project description:Omeprazole stimulated gene expression in rats Samples and RNA preparation: The series is composed of 9 hybridizations for analysis of differentially expressed genes in the gastric mucosa of omeprazole dosed vs. control rats. Nine rats (200-250 g) were given (by gavage) 400 micromol/kg of the proton pump inhibitor omeprazole (Astra AB, Gothenburg, Sweden) in Methocel (Dow Corning, Midland, MI) daily for 10 weeks. Seven rats received vehicle only. After 10 weeks the stomachs were removed for sampling of full-thickness corpus from the upper part of the greater curvature. Total RNA extraction was performed first by ultrasentrifugation on a cesium chloride cushion and then using TRIZOL Reagent (GIBCO BRL Life Technologies, New York, NY). Labeling and hybridization: Total RNA from 7 untreated rats were pooled and used as a common control. Three micrograms of total RNA from the control pool, and three micrograms of total RNA from each omeprazole dosed rat were reverse transcribed and labeled with capture sequences for subsequent attachment of Cy3- and Cy5-attached dendrimer, respectively, using 3DNA Array 350 Expression Array Detection kit as described in the manufacturer's protocols (Genisphere, Montvale, NJ). The labeling reactions were also spiked with exogenous control RNAs (Stratagene) at ratios of 1.0, 2.0, 3.0, 4.0, 5.0, 6.0, 0.5, 0.33, 0.25 and 0.125 for control spike 1, 2, 3, 4, 5, 6, 8, 9, 10 and 7, respectively. The slides were pre-washed in 2xSSC, 0.2% SDS at 55oC for 20 min, then 0.2x SSC at room temperature for 3 min, and deionized sterile filtered H2O at room temperature for 2 min. The Cy3 and Cy5 labeled samples (combined volume 9 microliter) were mixed with 25 microliter of the hybridization solution containing 0.25 M NaPO4, 1 mM EDTA, 4.5% SDS, 1 x SSC, 2 x Denhardt's solution and 2 microliter LNA dT Blocking reagent (Genisphere). A total hybridization volume of 50 microliter was added onto the array and covered with 24 x 60 mm cover slip. The array was assembled into humidified hybridization chamber (Corning) and hybridized at 60 oC for 18 h by submerging in a water bath. Post-hybridization washes were done once in 2 x SSC, 0.2% SDS at 55 oC for 15 min, then in 2 x SSC at room temperature for 15 min, and finally with 0.2 x SSC at room temperature for 15 min. After washing the fluorescent 3DNA reagent was hybridized to the cDNA at 60 oC for 3 h as described in the manufacturer's protocols. After dendrimer hybridization the slides were washed as described above. Scanning, image analysis and data processing: Arrays were scanned at 10 micrometer resolution with a ScanArray Express HT scanner (Packard BioSciences, Billerica, MA). The microarrays were analyzed using GenePixâ¢ Pro 4.1 (Axon Instruments, Inc., Union City, CA). All subsequent statistical analyses were performed using the statistical package R, R Development Core Team. A signal intensity based criterion was applied to remove the spots with median spot signal intensity less than 200. A spot area based criterion was applied to remove the spots with the area less than 50 pixels in either channel. Spots with more than 40% of the pixels saturated in either channel were also removed. Print tip-dependent normalization was applied to the data in order to compensate for systematic errors. The normalized ratios of the duplicated spots were averaged. Further analysis was done on the log2 transformed ratios. In order to assess the significance of up- or downregulation of the genes, tests for differential expression were performed using moderated T-tests, as implemented in the Limma R package of Smyth.

Project description:Omeprazole stimulated gene expression in rats Samples and RNA preparation: The series is composed of 9 hybridizations for analysis of differentially expressed genes in the gastric mucosa of omeprazole dosed vs. control rats. Nine rats (200-250 g) were given (by gavage) 400 micromol/kg of the proton pump inhibitor omeprazole (Astra AB, Gothenburg, Sweden) in Methocel (Dow Corning, Midland, MI) daily for 10 weeks. Seven rats received vehicle only. After 10 weeks the stomachs were removed for sampling of full-thickness corpus from the upper part of the greater curvature. Total RNA extraction was performed first by ultrasentrifugation on a cesium chloride cushion and then using TRIZOL Reagent (GIBCO BRL Life Technologies, New York, NY). Labeling and hybridization: Total RNA from 7 untreated rats were pooled and used as a common control. Three micrograms of total RNA from the control pool, and three micrograms of total RNA from each omeprazole dosed rat were reverse transcribed and labeled with capture sequences for subsequent attachment of Cy3- and Cy5-attached dendrimer, respectively, using 3DNA Array 350 Expression Array Detection kit as described in the manufacturer's protocols (Genisphere, Montvale, NJ). The labeling reactions were also spiked with exogenous control RNAs (Stratagene) at ratios of 1.0, 2.0, 3.0, 4.0, 5.0, 6.0, 0.5, 0.33, 0.25 and 0.125 for control spike 1, 2, 3, 4, 5, 6, 8, 9, 10 and 7, respectively. The slides were pre-washed in 2xSSC, 0.2% SDS at 55oC for 20 min, then 0.2x SSC at room temperature for 3 min, and deionized sterile filtered H2O at room temperature for 2 min. The Cy3 and Cy5 labeled samples (combined volume 9 microliter) were mixed with 25 microliter of the hybridization solution containing 0.25 M NaPO4, 1 mM EDTA, 4.5% SDS, 1 x SSC, 2 x Denhardt's solution and 2 microliter LNA dT Blocking reagent (Genisphere). A total hybridization volume of 50 microliter was added onto the array and covered with 24 x 60 mm cover slip. The array was assembled into humidified hybridization chamber (Corning) and hybridized at 60 oC for 18 h by submerging in a water bath. Post-hybridization washes were done once in 2 x SSC, 0.2% SDS at 55 oC for 15 min, then in 2 x SSC at room temperature for 15 min, and finally with 0.2 x SSC at room temperature for 15 min. After washing the fluorescent 3DNA reagent was hybridized to the cDNA at 60 oC for 3 h as described in the manufacturer's protocols. After dendrimer hybridization the slides were washed as described above. Scanning, image analysis and data processing: Arrays were scanned at 10 micrometer resolution with a ScanArray Express HT scanner (Packard BioSciences, Billerica, MA). The microarrays were analyzed using GenePix™ Pro 4.1 (Axon Instruments, Inc., Union City, CA). All subsequent statistical analyses were performed using the statistical package R, R Development Core Team. A signal intensity based criterion was applied to remove the spots with median spot signal intensity less than 200. A spot area based criterion was applied to remove the spots with the area less than 50 pixels in either channel. Spots with more than 40% of the pixels saturated in either channel were also removed. Print tip-dependent normalization was applied to the data in order to compensate for systematic errors. The normalized ratios of the duplicated spots were averaged. Further analysis was done on the log2 transformed ratios. In order to assess the significance of up- or downregulation of the genes, tests for differential expression were performed using moderated T-tests, as implemented in the Limma R package of Smyth. Keywords: repeat sample

Dataset Information

Gene expression profile in labouring and non-labouring human placenta near term

Dataset's files

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets