Biomedical subjects
Publications and source records attributed to S M Jacobs.
Nurse executives need to review what is working in other industries to see if similar techniques and philosophies can help the healthcare industry. The authors review the manufacturing philosophy supporting the just-in-time method and apply some of its principles to healthcare to improve operations and operating margins.
Nurse executives often are encouraged to work smarter, not harder. Decision support systems offer methods for refining the decision-making process. The authors review the types of decisions that managers make and the ways that decision support systems can help nurse executives work smarter.
Despite the frequent description of 6q- structural abnormalities in human leukemias and lymphomas, rearrangements of the c-MYB locus have not been detected. We have detected a rearrangement in the c-MYB proto-oncogene in the cell line CCRF-CEM, an immature T-cell leukemia cell line which is not 6q-. Due to this rearrangement, a large portion of the c-MYB promoter conserved between the human and murine c-MYB genes is lost. The rearranged locus, which we have designated MRR (MYB rearranged region), has been cloned and mapped to chromosome 6. Field inversion gel electrophoresis (FIGE) studies reveal that the MRR sequence is linked to the c-MYB locus, suggesting that the rearrangement is due to a submicroscopic deletion. The rearrangement appears to have no effect on c-MYB promoter activity as analyzed in CCRF-CEM cells. The normal locus of the MRR sequence has been cloned from a human placental genomic library. Partial sequence analysis of this clone reveals that a portion of the DNA lost in the rearrangement shows a high degree of homology to a member of the myc family of oncogenes. Thus the characterization of this rearrangement has yielded a new set of probes for the study of chromosome 6q abnormalities in human leukemias and lymphomas and provides the first evidence for potential involvement of the c-MYB locus itself in submicroscopic deletions within chromosome 6.
We have previously described an alternatively spliced cDNA clone of the human c-myb proto-oncogene which has been shown to enhance the differentiation of Friend murine erythroleukemia cells. This clone, pMbm-2, contains unique 5' sequences which replace exon 1. The human c-myb intron 1 was sequenced to determine the exact position of this unique sequence and to further characterize the role of intron 1 in the regulation of the human c-myb gene. Here we report that intron 1 of c-myb is highly conserved between human and mouse throughout the intron, while only those sequences directly adjacent to exons 1 and 2 are conserved between human and chicken. The unique sequence of pMbm-2 was located directly adjacent to exon 2, suggesting that it arose as a product of alternative transcription initiation within intron 1. RNAase protection analysis was used to map a cluster of transcription start sites at the 5' end of exon 2. Levels of messages utilizing these start sites are proportional to those arising from the primary promoter. Functional characterization of this region revealed that this region can function as a promoter. Deletion studies have revealed the presence of negative and positive regulatory elements within this region which are utilized with different efficiencies in different cell lines. These studies suggest that cis or trans factors acting in this region may serve a dual function in both attenuation and transcription initiation.