Saint Louis University

About: Saint Louis University is a education organization based out in St Louis, Missouri, United States. It is known for research contribution in the topics: Population & Poison control. The organization has 18927 authors who have published 34895 publications receiving 1267475 citations. The organization is also known as: SLU & St. Louis University.

Insulin-like Growth Factor Receptor Expression and Function in Human Breast Cancer

Abstract: The insulin-like growth factors IGF-I and IGF-II are potent mitogens for several breast tumor cell lines in culture. Additionally, both IGF-I and IGF-II mRNAs are easily detected in the majority of breast tumor specimens examined, while no breast cancer epithelial cell lines we have studied express authentic IGF-I mRNA, and few lines express IGF-II mRNA. Although receptors for insulin, IGF-I, and IGF-II have been described, there is significant cross-reactivity between the various receptors and ligands in the insulin/insulin-like growth factor family, and it is not clear which receptor or receptors are responsible for the biological effects of these growth factors in this system. Using an RNase protection assay, we examined breast tumor specimens and breast cancer epithelial cell lines for expression of mRNA encoding the type I and type II IGF receptors as well as the insulin receptor. Virtually all of the specimens examined expressed mRNA for all three receptors. We then examined estrogen-dependent MCF-7 cells for the mitogenic effects of IGF-I and II in the presence of antibodies to both the type I and type II receptors. alpha IR-3, a monoclonal antibody which blocks the type I receptor, abolished the mitogenic effects of both IGF-I and IGF-II. It did not, however, block the mitogenic effects of insulin. We conclude that type I and type II IGF receptors are ubiquitously expressed in breast cancer, and our experiments with MCF-7 cells suggest the mitogenic effects of both IGF-I and IGF-II are mediated via the type I IGF receptor.

Family Business Succession: Suggestions for Future Research:

Abstract: Management succession is a significant moment in a family business's life and an issue that requires analysis from the perspectives of family, management, and ownership systems in order to understand adequately the perspectives of the different stakeholders. In an effort to help improve the quality of the research methodology on this subject, past family business research methodology will be reviewed and critiqued, and some specific recommendations will be presented that can enhance the quality and value of family business research.

19-Nor-1-alpha-25-dihydroxyvitamin D2 (Paricalcitol) safely and effectively reduces the levels of intact parathyroid hormone in patients on hemodialysis.

Abstract: Paricalcitol (19-nor-1alpha-25-dihydroxyvitamin D2), a new vitamin D analog developed for the treatment of secondary hyperparathyroidism, was evaluated in three double-blind, placebo-controlled, dose-escalating, randomized multicenter trials. A total of 78 patients (40 Paricalcitol injection, 38 placebo) achieved treatment phase eligibility, which included intact parathyroid hormone (iPTH) > or = 400 pg/ml, normalized serum calcium levels between 8.0 and 10.0 mg/dl, and calcium x phosphorus product values less than 75. Study end points included a decrease in iPTH of at least 30% or a maximum of five dose escalations. After a 4-wk washout, paricalcitol or placebo was administered intravenously three times per week after dialysis for 12 wk. Study drug was started at a dose of 0.04 microg/kg and was increased by 0.04 microg/kg every 2 wk to a maximal allowable dose of 0.24 microg/kg or until at least a 30% decrease in serum iPTH was achieved. The dose of paricalcitol that decreased iPTH by at least 30% became the maintenance dose. Of 40 patients receiving paricalcitol, 27 (68%) had at least a 30% decrease in serum iPTH for 4 consecutive weeks, compared with three of 38 patients (8%) receiving placebo (P < 0.001). For patients who received 12 wk of treatment with paricalcitol, the levels of iPTH decreased significantly from 795+/-86 to 406+/-106 pg/ml (P < 0.001), whereas the values for PTH were 679+/-41 pg/ml before and 592+/-41 pg/ml after 12 wk of therapy in patients receiving placebo (P=NS). Also, there was a significant difference between treatment groups for the change from baseline PTH levels (P < 0.001). Paricalcitol treatment resulted in a significant reduction in serum alkaline phosphatase from 148+/-23 U/L to 101+/-14 U/L (P < 0.001) in patients treated for 12 wk compared with 120+/-9 U/L to 130+/-11 U/L (P=NS) in patients receiving placebo for 12 wk. Importantly, hypercalcemia did not occur before achieving target serum iPTH levels in any of the paricalcitol-treated patients. There was no significant difference for the change from baseline in serum phosphorus within or between treatment groups. There was no significant difference in adverse events between the paricalcitol and placebo-treated groups. These studies demonstrate that paricalcitol safely and effectively suppresses iPTH levels in hemodialysis patients. This second generation vitamin D analog may have a wider therapeutic window than current vitamin D preparations, and thus may allow reduction in PTH with less hypercalcemia.