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Sample GSM344657 Query DataSets for GSM344657
Status Public on Jun 01, 2010
Title T00306162: cardiomyocytes, 24 hour unconditioned
Sample type RNA
 
Source name cardiomyocytes, 24 hour unconditioned
Organism Rattus norvegicus
Characteristics Rat neonatal cardiomyocytes harvested from day 1 ventricles (n=24). Cells purified via serial Percoll gradients and plated at 2.5x10^5 cells per 100 mm sq dish.
Extracted molecule total RNA
Extraction protocol Extracted using Invitrogen Trizol LS Reagent and Invitrogen's RNA isolation protocol supplied with the reagent.
Label biotin
Label protocol GE Healthcare Amersham CodeLink iExpress Assay Reagent Kit protocol
 
Hybridization protocol GE Healthcare Amersham CodeLink Gene Expression System: Single-Assay Bioarray Hybridization and Detection protocol
Detection dye: streptavidin - Alexa Fluor 647
Scan protocol Scanned using a GenePix 4000B at 600 PMT and CodeLink software (version 5.0).
Description Cardiac media was diluted 50% with unconditioned hesc media while FBS and HS percentages were held constant at 5% and 10% respectively.
RNA extracted after 24 hours.
Data processing The threshold was calculated by removing the top 10% and bottom 10% of negative controls and averaging the remaining intensities. The threshold was subtracted from each of the discovery probes. An average was computed for the following positive controls: LEUB, HISB, FIXB (FIXB_PROBE2 was not used on arrays T00306161 and T00306162 because its intensity was greater than 2 standard deviations away from the mean), GND, ENTF, and ARAB. The averages of each of these positive controls was grouped together with its average on all the other arrays in this series. By taking the median of each group, a global median was created which represents the median value for a positive control across all of the arrays. Correction factors for this array were calculated by dividing the average of each positive control by its corresponding global median. It was observed that the arrays behaved differently at high intensity levels compared to low intensity levels. As the positive controls increased in intensity, the correction factors also steadily increased or steadily decreased. Therefore, a correction factor derived from a low intensity positive control was not a good correction for high intensity probes. To accommodate for the effect of intensity, the correction factor for each positive control was graphed versus its intensity and a best-fit regression line was created. The equation of the best-fit line was used to calculate a correction factor for each individual discovery probe based on where it fit into the slope of the correction factors. Negative values were replaced by a placeholder of ".0001".
In summary, the data was normalized by comparing each positive control to its median value across arrays and correcting based on the slope of the positive controls versus intensity. Note that the data was never median normalized or log transformed.
 
Submission date Nov 21, 2008
Last update date Jun 16, 2009
Contact name John Michael Krill-Burger
E-mail(s) burgerm@upmc.edu
Phone 412-656-6727
Organization name University of Pittsburgh Medical Center
Street address Rm. WG21.3 Shadyside Hospital
City Pittsburgh
State/province PA
ZIP/Postal code 15232
Country USA
 
Platform ID GPL2896
Series (1)
GSE13708 Stem Cells Secrete Factors That Induce Proliferation In Differentiated Cardiomyocytes

Data table header descriptions
ID_REF
Raw_Intensity Raw Intensity
VALUE Normalized Intensity

Data table
ID_REF Raw_Intensity VALUE
1001 12799.375 null
1002 18.64286041 3.908673627
1003 null null
1004 76.77777863 58.07840364
1005 12068.2959 11232.9499
1006 2341.185303 2168.083932
1007 14864.33301 null
1008 13703.58105 null
1009 218.5882263 190.2166815
1010 11.38461304 0.0001
1011 18.32257843 3.610237169
1012 394.6000061 354.2240781
1013 1522.920044 1405.603033
1014 14509.82324 null
1015 17837.17578 null
1016 33.33333588 17.59715539
1017 36.5 20.54783124
1018 17.84615326 3.16630761
1019 57.46666718 40.08443196
1020 2877.185303 2667.549008

Total number of rows: 36736

Table truncated, full table size 1004 Kbytes.




Supplementary data files not provided
Processed data included within Sample table

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