THE MANAGEMENT OF RENAL CELL CARCINOMA WITH INFERIOR VENA-CAVAL INVOLVEMENT

Seven patients with renal cell carcinoma involving the inferior vena cava underwent surgical resection between 1975 and 1991. Pre-operative staging defined five patients with stage T3bNoMo disease, one patient with stage T3bN₁Mo, and one patient with stage T3bNoM 1 disease.¹ At operation one patient had tumour thrombus filling the right atrium. Two patients had tumour thrombus within the intrahepatic vena cava and four infrahepatic tumour thrombus. The mean follow-up is 34.4 months (median 40 months). Four patients have been followed for over 4 years. Three of these patients are survivors, two have remained disease-free since their initial surgery. The other patient had a liver resection at 49 months for a solitary metastases; he is currently disease free. One patient died at 38 months from a gastrointesinal haemorrhage. Three patients are 12 months or less postoperation. Operative mortality was zero. The mean postoperative hospital stay was 14.7 days. Data suggests that 3–10% of renal cell carcinomas will involve the inferior vena cava.² The small number of patients in this series suggests that many patients with renal cell carcinoma involving the inferior vena cava are not referred for surgical assessment. These patients are potential surgical candidates. Their survival after surgical resection, excluding the group with extension of tumour thrombus into the hepatic cava or above, is not reduced when compared with other patients with renal carcinoma.^3,4     

Development and characterization of a normalized canine retinal cDNA library for genomic and expression studies

PURPOSE: Identification of causative mutations for retinal blinding disorders is often limited by restricted understanding of gene expression and underlying molecular mechanisms that trigger degenerative processes. This study was conducted to develop a catalog of canine retina-expressed genes that would provide a unique tool to investigate normal and altered function in the adult retina. Because of the conserved syntenies between the dog and human, this approach would identify new potential disease candidate genes for both species. METHODS: A canine normalized retinal cDNA library was produced and analyzed by using a modified PhredPhrap algorithm. Computerized annotation provided gene homology and chromosomal location for individual clones and contigs in a Web-accessible database. RESULTS: From 6316 cDNA clones, 3980 retinal expressed sequence tags (ESTs) were derived. Homology to the canine genome draft sequence was found for more than 99% of all ESTs, but only for 32% when compared with annotated canine cDNAs. Functional analysis suggests an enrichment of this library for genes involved with eye function and development, chaperone, or ribosomal functions when compared with mouse and human National Center for Biotechnology Information (NCBI) RefSeq entries. CONCLUSIONS: A combination of annotation approaches with ongoing mapping and expression studies provide functional data covering at least 27% to 30% of the currently proposed canine catalog of genes expressed in the retina. This is an essential first step toward establishing an integrated network for gene identification and expression patterns suitable for functional genetics, comparative genomics and evolutionary analysis of genes and gene families with respect to the developmental and degenerative processes of the retina.     

Impact of folivory on photosynthesis is greater than the sum of its holes

The effects of herbivores on plant production and fitness may not relate directly to the quantity of biomass removed because folivory may alter photosynthetic rates at a considerable distance from the damaged tissue [Welter, S. C. (1989) in Insect-Plant Interactions, ed. Bernays, E. A. (CRC, Boca Raton), pp. 135-151.]. An impediment to understanding the effects of leaf damage on photosynthesis has been an inability to map photosynthetic function within a single leaf. We developed an instrument for imaging chlorophyll fluorescence and used it to map the effects of caterpillar feeding on whole-leaf photosynthesis in wild parsnip. The adverse effects of caterpillar feeding on photosynthesis were found to extend well beyond the areas of the leaflet in which caterpillars removed tissue. These "indirectly" affected areas remained impaired for at least 3 days after the caterpillars were removed and were six times as large as the area directly damaged by the caterpillars. Although photosynthesis in indirectly affected areas was reduced and not eliminated, these areas accounted for three times as much of the overall reduction in photosynthesis as the area removed by the caterpillars. The size of the indirect effects was positively correlated with defense-related synthesis of furanocoumarins, suggesting that costs of chemical defense may be one factor that accounts for the indirect effects of herbivory on plants.