Saint Francis University

About: Saint Francis University is a education organization based out in Loretto, Pennsylvania, United States. It is known for research contribution in the topics: Population & Osteoblast. The organization has 1694 authors who have published 2038 publications receiving 87149 citations.

Transforming growth factor-beta and remodeling of bone.

Abstract: The transforming growth factor-betas are polypeptide growth factors encoded by a family of closely related genes that are expressed in numerous tissues and species. Bone was one of the first tissues in which locally produced molecules with transforming growth factor-beta-like activity appeared to regulate normal cellular function, and the skeletal matrix probably comprises the largest reservoir of transforming growth factor-betas in the organism. In vitro and in vivo studies have indicated that the transforming growth factor-betas can have either stimulatory or inhibitory effects on replication, lineage development, and differentiated phenotypic function in many types of skeletal tissue cells. These effects may be biphasic in the sense that low concentrations of transforming growth factor-beta stimulate proliferation of cells, whereas high concentrations inhibit proliferation. Even within the same cell lineage, opposite effects have been noted with different concentrations of transforming growth factor-beta, or with skeletal cells at different developmental stages. In fetal tissue, transforming growth factor-beta stimulates differentiation of mesenchymal cells, proliferation of osteoblasts, and synthesis of matrix, but it may also induce maturation into and through the osteoblast, chondrocyte, and osteoclast lineages. Furthermore, a number of other local and systemic factors can regulate expression of transforming growth factor-beta or receptor-binding by bone cells or can increase release of transforming growth factor-beta from the skeletal matrix. Some activities ascribed to the transforming growth factorbetas may overlap with those produced by osteoinductive factors and other less closely related members of the transforming growth factor-beta gene family. Consequently, a thorough understanding of activity, synthesis, and receptors of transforming growth factor-beta may result in the rational use of these or related molecules to enhance growth of bone or repair of fractures.

Effects of platelet-derived growth factor on bone formation in vitro.

Abstract: Platelet-derived growth factor (PDGF) is a polypeptide found in a variety of tissues, including bone, where it could act as an autologous regulator of skeletal remodeling. Therefore, a recombinant B chain homodimer of human PDGF was studied for its effects on bone formation in cultured rat calvariae. PDGF at 10-100 ng/ml stimulated [3H]thymidine incorporation into DNA by up to sixfold and increased the DNA content and the number of colcemid-induced metaphase arrested cells. This effect was observed in the fibroblast and precursor cell-rich periosteum. As a result of its mitogenic actions, PDGF enhanced [3H]proline incorporation into collagen, an effect that was observed primarily in the osteoblast-rich central bone. The effect of PDGF was not specific for collagen since it also increased noncollagen protein synthesis. In addition, PDGF increased bone collagen degradation. PDGF and insulin-like growth factor (IGF) I had additive effects on calvarial DNA synthesis, but PDGF opposed the stimulatory effect of IGF I on collagen synthesis and IGF I prevented the PDGF effect on collagen degradation. In conclusion, PDGF stimulates calvarial DNA synthesis which causes an increased number of collagen-synthesizing cells, but PDGF also enhances bone collagen degradation.

Disparities in Ovarian Cancer Care Quality and Survival According to Race and Socioeconomic Status

Abstract: cancer diagnosed in the period from 1998 to 2002 was done using data from patients classified as white or black. Adherence to National Comprehensive Cancer Network (NCCN) guideline care was defined by stage-appropriate surgical procedures and recommended chemotherapy. The main outcome measures were differences in adherence to NCCN guidelines and overall survival according to race and SES and were analyzed using binomial logistic regression and multilevel survival analysis. Results A total of 47 160 patients (white = 43 995; black = 3165) were identified. Non-NCCN-guideline-adherent care was an independent predictor of inferior overall survival (hazard ratio [HR] = 1.43, 95% confidence interval [CI] = 1.38 to 1.47). Demographic characteristics independently associated with a higher likelihood of not receiving NCCN guideline-adherent care were black race (odds ratio [OR] = 1.36, 95% CI = 1.25 to 1.48), Medicare payer status (OR = 1.20, 95% CI = 1.12 to 1.28), and not insured payer status (OR = 1.33, 95% CI = 1.19 to 1.49). After controlling for disease and treatment-related variables, independent racial and SES predictors of survival were black race (HR = 1.29, 95% CI = 1.22 to 1.36), Medicaid payer status (HR = 1.29, 95% CI = 1.20 to 1.38), not insured payer status (HR = 1.32, 95% CI = 1.20 to 1.44), and median household income less than $35 000 (HR = 1.06, 95% CI = 1.02 to 1.11). Conclusions These data highlight statistically and clinically significant disparities in the quality of o varian cancer care and overall survival, independent of NCCN guidelines, along racial and SES parameters. Increased efforts are needed to more precisely define the patient, provider, health-care system, and societal factors leading to these observed disparities and guide targeted interventions.