Identification of an amplified gene cluster in glioma including two novel amplified genes isolated by exon trapping

Gene amplification, which occurs in more than 50% of malignant gliomas, is considered to play a pivotal role in tumorigenesis. There are, however, few studies aimed toward the isolation of novel genes from amplified sequences. Previously, we reported amplification of the protooncogene MET (hepatocyte growth factor receptor; 7q31) in more than 20% of glioblastomas. For an approximate size estimation of the amplification unit we analyzed three glioblastomas all of which carried an amplified MET gene, by Southern blot analysis and/or competitive polymerase chain reaction using eight DNA markers. Although the extent of the amplified domain varied, the close vicinity of the MET gene was the only region consistently amplified in these glioblastomas. A yeast artificial chromosome (YAC) contig of 900 kb was refined spanning the amplified region flanking the MET gene. The YAC inserts were subcloned into 59 cosmids, which were used for exon trapping. Eight sequences were identical to parts of the genes MET and CAPZA2 (human actin capping protein alpha-subunit). Two newly identified exons and the CAPZA2 exons were amplified in tumor TX3095, which retains an amplified MET gene. The new exons were localized close to MET and CAPZA2. Characterization of the clones, which were termed glioma-amplified sequence (GAS)7-1 and GAS7-2, showed an open reading frame and a different expression pattern in multiple human tissues. This study reports the identification of a cluster of amplified genes including two novel genes in a region amplified in more than 20% of glioblastomas.

Validation of Portable Ergonomic Observation (PEO) method using optoelectronic and video recordings

The validity of the 'Portable Ergonomic Observation' method (PEO) was investigated against posture measurements based on continuous optoelectronic and video recordings made simultaneously with the observation. Work postures and actions during different frequently changing tasks were analyzed using both methods. In general, a high agreement between measured and observed data was achieved for the duration of clearly identifiable sustained postures and actions (such as repetitive movements of hands when typing), as well as for the frequency of clearly distinguishable actions (such as lifts). The agreement between observations and measurements was low for neck postures. In dynamic tasks the agreement was generally low. This was probably because of high levels of simultaneous information for the observer. No improvement in the agreement between measured and observed events could be achieved by leaving parts of the PEO categories unobserved at a time. Playback of video tapes to observe each category separately would increase the reliability of the observations but at the expense of increased time for the analysis.