The differentiation of small intestinal epithelial cells may require stimulation by microenvironmental factors in vivo. In this study, the effects of mesenchymal and luminal elements in nonmalignant ...epithelial cells isolated from the human fetus were studied in vitro. Enterocytes from the human fetus were cultured and microenvironmental factors were added in stages, each stage more closely approximating the microenvironment in vivo. Four stages were examined: epithelial cells derived on plastic from intestinal culture and grown as a cell clone, the same cells grown on connective tissue support, primary epithelial explants grown on fibroblasts with a laminin base, and primary epithelial explants grown on fibroblasts and laminin with n-butyrate added to the incubation medium. The epithelial cell clone dedifferentiated when grown on plastic; however, the cells expressed cytokeratins and villin as evidence of their epithelial cell origin. Human connective tissue matrix from Engelbreth-Holm-Swarm sarcoma cells (Matrigel) modulated their phenotype: alkaline phosphatase activity increased, microvilli developed on their apical surface, and the profile of insulin-like growth factor binding proteins resembled that secreted by differentiated enterocytes. Epithelial cells taken directly from the human fetus as primary cultures and grown as explants on fibroblasts and laminin expressed greater specific enzyme activities in brush border membrane fractions than the cell clone. These activities were enhanced by the luminal molecule sodium butyrate. Thus the sequential addition of connective tissue and luminal molecules to nonmalignant epithelial cells in vitro induces a spectrum of changes in the epithelial cell phenotype toward full differentiation.
In this work, we present the Genome Modeling System (GMS), an analysis information management system capable of executing automated genome analysis pipelines at a massive scale. The GMS framework ...provides detailed tracking of samples and data coupled with reliable and repeatable analysis pipelines. The GMS also serves as a platform for bioinformatics development, allowing a large team to collaborate on data analysis, or an individual researcher to leverage the work of others effectively within its data management system. Rather than separating ad-hoc analysis from rigorous, reproducible pipelines, the GMS promotes systematic integration between the two. As a demonstration of the GMS, we performed an integrated analysis of whole genome, exome and transcriptome sequencing data from a breast cancer cell line (HCC1395) and matched lymphoblastoid line (HCC1395BL). These data are available for users to test the software, complete tutorials and develop novel GMS pipeline configurations. The GMS is available at https://github.com/genome/gms.
The selective 5-hydroxytryptamine3 (5HT3) antagonist ondansetron has been shown to be an effective antiemetic in patients receiving cisplatin chemotherapy. This double-blind study compared the ...efficacy and safety of three doses of intravenous ondansetron in the prevention of nausea and vomiting associated with high-dose (> or = 100 mg/m2) cisplatin chemotherapy. A total of 125 patients were randomized (1:1:1) to receive 0.015, 0.15, or 0.30 mg/kg every 4 h for a total of 3 doses. All patients were monitored for emetic episodes, adverse events, and laboratory safety parameters for 24 h following cisplatin administration. The 0.15-mg/kg dose was superior to the 0.015-mg/kg dose with respect to the median number of emetic episodes (P = 0.033) and complete response (no emetic episodes, P = 0.005). No statistically significant difference was found between the 0.15 and the 0.30-mg/kg groups. The most common adverse event was headache. Three 0.15-mg/kg doses of intravenous ondansetron are safe, effective, and adequate for the control of cisplatin-induced emesis.
The Ugi protein inhibitor of uracil-DNA glycosylase encoded by bacteriophage PBS2 inactivates human uracil-DNA glycosylases (UDG) by forming a tight enzyme:inhibitor complex. To create human cells ...that are impaired for UDG activity, the human glioma U251 cell line was engineered to produce active Ugi protein. In vitro assays of crude cell extracts from several Ugi-expressing clonal lines showed UDG inactivation under standard assay conditions as compared to control cells, and four of these UDG defective cell lines were characterized for their ability to conduct in vivo uracil-DNA repair. Whereas transfected plasmid DNA containing either a U:G mispair or U:A base pairs was efficiently repaired in the control lines, uracil-DNA repair was not evident in the lines producing Ugi. Experiments using a shuttle vector to detect mutations in a target gene showed that Ugi-expressing cells exhibited a 3-fold higher overall spontaneous mutation frequency compared to control cells, due to increased C:G to T:A base pair substitutions. The growth rate and cell cycle distribution of Ugi-expressing cells did not differ appreciably from their parental cell counterpart. Further in vitro examination revealed that a thymine DNA glycosylase (TDG) previously shown to mediate Ugi-insensitive excision of uracil bases from DNA was not detected in the parental U251 cells. However, a Ugi-insensitive UDG activity of unknown origin that recognizes U:G mispairs and to a lesser extent U:A base pairs in duplex DNA, but which was inactive toward uracil residues in single-stranded DNA, was detected under assay conditions previously shown to be efficient for detecting TDG.
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