Encapsulating peritoneal sclerosis (EPS) is a rare but devastating complication of peritoneal dialysis characterized by fibrosis and calcification of the intestine that, in severe cases, can progress to intestinal failure and total parenteral nutrition dependency. Medical and surgical interventions carry a poor prognosis in these patients. We describe a case of a 36-year-old female with end-stage kidney disease and severe EPS not amenable to surgical intervention who underwent a combined intestinal and kidney transplantation. At 3 years posttransplantation, the patient has normal intestinal and kidney function. This represents, to our knowledge, the first report of severe EPS and end-stage kidney disease treated with a combined transplant.
Increased expression of proteases has been correlated with the malignant progression of a variety of tumors. We found a significant increase in cathepsin H expression in high-grade prostatic intraepithelial neoplasia and carcinoma of the prostate. Two forms of cathepsin H, the full-length form (CTSH) and a truncated form with a 12-amino acid deletion in its signal peptide region (CTSHΔ10–21), were identified by cDNA sequence analysis. This deletion occurred not at the genomic level but likely at the RNA processing level. Both forms are expressed in prostate tissues as well as LNCaP, PC-3, and DU-145 prostate cancer cell lines. The deletion within the signal peptide region affected the trafficking of cathepsin H. Fluorescence microscopy, subcellular fractionation, and activity data indicated that the truncated form was perinuclear and secreted and had a reduced lysosomal association as compared with the full-length cathepsin H. Furthermore, the truncated cathepsin H was enzymatically active. Therefore, an increase in overall cathepsin H expression, particularly in the truncated form with a high secretion propensity, may affect cell biological behaviors such as those associated with tumor progression.
A common therapy for nonorgan-confined prostate cancer involves androgen deprivation. To develop a better understanding of the effect of androgen on prostatic cells, we have analyzed gene expression changes induced by dihydrotestosterone (DHT) in the androgen responsive prostate cancer line LNCaP, at both RNA and protein levels. Changes at the RNA level induced by DHT were determined by means of serial analysis of gene expression (SAGE), and protein profiling was done by means of quantitative two-dimensional polyacrylamide gel electrophoresis. Among 123 371 transcripts analyzed, a total of 28844 distinct SAGE tags were identified representing 16 570 genes. Some 351 genes were significantly affected by DHT treatment at the RNA level (p<0.05), of which 147 were induced and 204 repressed by androgen. In two independent experiments, the integrated intensity of 32 protein spots increased and 12 decreased at least two-fold in response to androgen, out of a total of 1031 protein spots analyzed. The change in intensity for most of the affected proteins identified could not be predicted based on the level of their corresponding RNA. Our study provides a global assessment of genes regulated by DHT and suggests a need for profiling at both RNA and protein levels for a comprehensive evaluation of patterns of gene expression.
Prostate cancer is the leading cause of cancer death in American males. To better understand the genetic bases of this disease, we have generated a comprehensive molecular profile of human prostate. The gene expression pattern in normal and prostate cancer tissues was analyzed by serial analysis of gene expression (SAGE). A total of 133,217 transcripts were analyzed, and 35,185 distinct SAGE tags were identified representing 19,287 genes. Comparison of the transcripts in normal and tumor tissue revealed 156 differentially expressed genes (P < 0.05), of which 88 genes were up-regulated and 68 genes were down-regulated in the tumor tissue. Based on SAGE data, we estimate that the transcriptome for human prostate is approximately 37,000. Several differentially expressed genes identified by SAGE were selected for confirmation using immunohistochemistry. Some genes (e.g., E2F4) were overexpressed in tumor epithelial cells and some (e.g., Daxx) were increased in tumor stroma. Further characterization of the role of E2F4 and Daxx as well as other differentially expressed genes may provide useful insights into the mechanism of prostate cancer development.
Research into molecular and cellular defects underlying prostate cancer would be advanced by in vitro models of prostate tumor cells representing patient tumors. We have propagated, in serum-free medium, epithelial cell cultures derived from nondiploid prostate tumors and normal human prostate. The serial passage tumor cells exhibited nondiploid karyotype and transformed phenotypes of focus formation and anchorage-independent growth. In contrast, the normal prostate cells showed diploid karyotype and lacked transformed phenotypes. Both the tumor and normal cells were positive for prostate-specific antigen and cytokeratins 18 and 19 and negative for keratin 15. These results demonstrate that the nondiploid prostate tumors and normal prostate epithelial cell cultures retained their respective in vivo properties and should allow studies to elucidate molecular alterations involved in human prostate cancer.
The addition of alkali species to supported Ru catalysts has been found to have a significant effect on selectivity in the hydrogenation of unsaturated aldehydes. In this paper, the role of the alkali species and its interactions with Ru and with the support are explored by examining the behavior of differently prepared promoted catalysts.
The hydrogenation of 3-methyl 2-butenal over Ru was investigated to study the influence of alkali promoters and of the type of support on the activity and selectivity. Alkali species increased selectivity of Ru to the unsaturated alcohol, an effect which was observed both for alkali-promoted Ru/SiO2 and for Ru supported on Y zeolites with different alkali compensating cations. The gas-phase reactions were strongly diffusion limited over the zeolite-supported Ru catalysts.
Flow reaction studies of the hydrogenation of 3-methyl-2-butenal over Ru/SiO2 and potassium-promoted Ru/SiO2 were combined with in situ infrared spectroscopic monitoring of its adsorption and reaction as well as the adsorption of its reaction products. The presence of the alkali promoter significantly inhibited this hydrogenation to form the saturated aldehyde, a reaction which was followed by decarbonylation of the saturated aldehyde in a reverse migratory insertion process. The initial formation of adsorbed CO and hydrocarbon products from the saturated aldehyde may ultimately be responsible for the product distribution observed under steady-state reaction conditions.
The addition of potassium as a promoter to a Ru/SiO2 catalyst resulted in a striking shift in product selectivity in the hydrogenation of 3-methyl-2-butenal. The rate of hydrogenation at the C=O bond to produce the unsaturated alcohol increased concomitant with a decrease in the rate of C=C hydrogenation. IR spectroscopy showed a strong perturbation of the C=O bond for the alkali-promoted catalyst, and volumetric chemisorption and TPD results suggested that the alkali species blocked adsorption at low-coordination Ru sites. These adsorption and reaction studies suggest that polarization of the adsorbed substrate at the C=O bond is responsible for the significant shift in product selectivity upon alkali promotion. This work combines spectroscopic tools with the use of the catalytic reaction itself as a probe of catalyst surface chemistry.