The advantage of using SNP array in clinical testing for hematological malignancies--a comparative study of three genetic testing methods.

Cytogenetic methods, including G-banded chromosome analysis and fluorescence in situ hybridization (FISH) analysis, serve as a critical part of routine clinical testing for hematological malignancies and provide important diagnostic and prognostic information; however, the limitations of cytogenetic methods, including the requirement for actively dividing cells and lower resolution of G-banded chromosome analysis as well as the inability of both G-banded chromosome analysis and FISH to detect copy number neutral loss of heterozygosity (CN-LOH), can result in a failure to detect genomic abnormalities with diagnostic and prognostic significance. Here, we compared the abnormality detection rate of clinically requested testing (i.e., G-banded chromosome analysis and FISH) with high-resolution oligo (i.e., array comparative genomic hybridization (aCGH)) and single-nucleotide polymorphism (SNP)/oligo hybrid (i.e., SNP-CGH) arrays in a series of patients, in an effort to assess the ability of newer technologies to overcome these limitations. This series found the detection rate for SNP-CGH to be 62.5% for myelodysplastic syndrome (MDS) cases and 72.7% for chronic lymphocytic leukemia (CLL) cases, which are significantly higher than the detection rates of aCGH (31.3% for MDS and 54.5% for CLL) and G-banding and/or FISH (43.8% for MDS and 54.5% for CLL). This demonstrates the advantages of combining SNP-CGH with conventional cytogenetics to provide comprehensive clinical information by detecting clonality, large balanced rearrangements, copy number aberrations, and CN-LOH.

Total parenteral nutrition attenuates cerulein-induced pancreatitis in rats.

OBJECTIVES: Our aim was to determine if total parenteral nutrition (TPN)-induced pancreatic atrophy and Hsp70 expression attenuates cerulein-induced pancreatitis in rats. METHODS: Rats were randomized to a 7-day course of saline infusion plus a semipurified diet or TPN, with or without an intravenous cerulein injection or vehicle on day 7, and killed 1 or 6 hours after the injection. Based on a pilot study, 1 hour was the primary time point. Pancreatic atrophy was determined by mass, protein, and DNA contents. Pancreatic heat shock protein 70 (Hsp70) expression was measured by Western analysis. Histological examination of the pancreas assessed for edema, inflammation, vacuolization, and apoptosis. Serum amylase activity was measured using the Phadebas assay. Pancreatic trypsinogen activation was measured using a fluorometric substrate assay. RESULTS: The saline-infused rats fed orally gained significantly more weight than TPN rats. The TPN decreased the pancreatic mass and protein content and the protein-DNA ratio and increased the pancreatic DNA content compared with the saline. The TPN increased the pancreatic Hsp70 expression by 91% compared with the saline. The TPN reduced the cerulein-induced pancreatic histological edema, the vacuolization, and the inflammation compared with the saline. The increase in the serum amylase level after cerulein injection was significantly attenuated, and trypsinogen activation was reduced in TPN animals compared with the saline group. CONCLUSIONS: Lack of luminal nutrients with a 7-day course of TPN provides moderate protection against cerulein-induced pancreatitis in rats.