Two types of genetic information were assessed in this case-comparison study: a) We collected and assessed all available information about the gene or chromosomal abnormalities characteristic of a child's leukemia cells that were ascertained at case presentation from bone marrow specimens and used for diagnosis and classification of leukemia.
Much of our knowledge of the resistance phenotypes in ALL has been derived using isolated bone marrow specimens studied in short-term culture using the 3- 4,5-dimethylthiazol-2-yl -2,5-diphenyltetrazolium bromide (MTT) assay.
To obtain primary myeloma cells, CD138+ cells were isolated from bone marrow specimens obtained through the Norwegian Myeloma Biobank using RoboSep automated cell separator and the Human CD138 Positive Selection Kit (StemCell Technologies, Grenoble, France).
Bone marrow specimens (3 5 ml) from 35 healthy bone marrow donors were used as negative controls to test the specificity of the RT-PCR assays.
Disease staging was determined using chest X-rays, technetium 99m bone scan, computed tomography or magnetic resonance imaging, and the evaluation of bone marrow specimens.
RESULTS: From 1992-1996, 1225 bone marrow specimens were submitted for mycobacterial and fungal cultures.
DHS provided normal bone marrow specimens.
Tumorous bone marrow infiltration of less than 1% was diagnosed in bone marrow specimen.
DNA was extracted from serum (n=4), blood (n=25), blood culture (n=9), and bone marrow (n=2) specimens by using the chaotropic properties of guanidine isothiocyanate, followed by DNA extraction and purification by alcohol precipitation with the IsoQuick Nucleic Acid Extraction Kit (ORCA Research, Bothell, WA).
In all experiments, DNA from lymphoma specimens without bone marrow infiltration were used as the negative control sample, and methylated control DNA (CpGenome Universal Methylated DNA, Chemicon, Millipore SPA, Italy) was used as the positive control.
