Search Constraints
Search Results
- Creator:
- Yarborough, Jonathan R., Medh, Rheem D., Shankar, Deepa B., Todd, Jennifer, Lee, Lee H., Okafor, Chiedozie, Morris, Devin, Kirzner, Jonathan D., Sakamoto, Kathleen M., Perez, Winder, Chu, Tin-Chun, Murray, Sean R., Nary, Laura J., and Priceman, Saul J.
- Description:
- Glucocorticoid (GC)-evoked apoptosis of T-lymphoid cells is preceded by increases in the intracellular Ca2+ concentration ([Ca2+]i), which may contribute to apoptosis. This report demonstrates that GC-mediated upregulation of the bZIP transcriptional repressor gene, E4BP4, is dependent on [Ca2+]i levels, and correlates with GC-evoked apoptosis of GC-sensitive CEM-C7-14 cells. Calcium chelators EGTA and BAPTA reduced [Ca2+]i levels and protected CEM-C7-14 cells from Dex-evoked E4BP4 upregulation as well as apoptosis. In the GC-resistant sister clone, CEM-C1-15, Dex treatment did not induce [Ca2+]i levels, E4BP4 expression or apoptosis, however, the calcium ionophore A23187 restored Dex-evoked E4BP4 upregulation and apoptosis. CEM-C7-14 cells were more sensitive to GC-independent increases in [Ca2+]i levels by thapsigargin, and a corresponding increase in E4BP4 expression and cell death, compared to CEM-C1-15 cells, suggesting a direct correlation between [Ca2+]i levels, E4BP4 expression, and apoptosis.
- Resource Type:
- Article
- Identifier:
- 0006-291X
- Campus Tesim:
- Northridge
- Creator:
- Saumell, Maria, Medh, Rheem D., Shankar, Deepa B., Fernandez, Silvia, Morris, Devin, Abrego, Bernardo, Hurtado, Ferran, Sakamoto, Kathleen M., Priceman, Saul J., Fabila-Monroy, Ruy, Flores-Penaloza, David, Sacristan, Vera, Kirzner, Jonathan D., and Nary, Laura J.
- Description:
- Let P be a set of n points in the plane. A geometric proximity graph on P is a graph where two points are connected by a straight-line segment if they satisfy some prescribed proximity rule. We consider four classes of higher order proximity graphs, namely, the k-nearest neighbor graph, the k-relative neighborhood graph, the k-Gabriel graph and the k -Delaunay graph. For k=k= (k=1k=1 in the case of the k-nearest neighbor graph) these graphs are plane, but for higher values of k in general they contain crossings. In this paper, we provide lower and upper bounds on their minimum and maximum number of crossings. We give general bounds and we also study particular cases that are especially interesting from the viewpoint of applications. These cases include the 1-Delaunay graph and the k-nearest neighbor graph for small values of k.
- Resource Type:
- Article
- Identifier:
- 0925-7721
- Campus Tesim:
- Northridge
- Creator:
- Medh, Rheem D., Shankar, Deepa B., Morris, Devin, Kirzner, Jonathan D., Sakamoto, Kathleen M., Priceman, Saul J., and Nary, Laura J.
- Description:
- Glucocorticoid (GC)-evoked apoptosis of T-lymphoid cells is preceded by increases in the intracellular Ca2+ concentration ([Ca2+]i), which may contribute to apoptosis. This report demonstrates that GC-mediated upregulation of the bZIP transcriptional repressor gene, E4BP4, is dependent on [Ca2+]i levels, and correlates with GC-evoked apoptosis of GC-sensitive CEM-C7-14 cells. Calcium chelators EGTA and BAPTA reduced [Ca2+]i levels and protected CEM-C7-14 cells from Dex-evoked E4BP4 upregulation as well as apoptosis. In the GC-resistant sister clone, CEM-C1-15, Dex treatment did not induce [Ca2+]i levels, E4BP4 expression or apoptosis, however, the calcium ionophore A23187 restored Dex-evoked E4BP4 upregulation and apoptosis. CEM-C7-14 cells were more sensitive to GC-independent increases in [Ca2+]i levels by thapsigargin, and a corresponding increase in E4BP4 expression and cell death, compared to CEM-C1-15 cells, suggesting a direct correlation between [Ca2+]i levels, E4BP4 expression, and apoptosis.
- Resource Type:
- Article
- Identifier:
- 0006-291X
- Campus Tesim:
- Northridge