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.

Growth Factor Control of Bone Mass

Abstract: Bone formation is determined by the number and function of osteoblasts. Cell number is governed by factors that regulate the replication and differentiation of pre-osteoblasts and factors that regulate osteoblastic cell death. Cell function is controlled by signals acting on the mature osteoblast. Platelet-derived and fibroblast growth factors are bone cell mitogens. Bone morphogenetic proteins (BMPs) and Wnt induce the differentiation of mesenchymal cells toward osteoblasts, and insulin-like growth factor (IGF)-I stimulates the function of mature osteoblasts and prevents their death. The activity of BMP, Wnt, and IGF-I is modulated by extracellular antagonists or binding proteins. Changes in growth factor synthesis and activity may play a role in the pathogenesis of selected forms of osteoporosis, and alterations in the expression or binding of the extracellular antagonists can be associated with changes in bone mass. Current approaches to bone anabolic therapies for osteoporosis include the administration of a growth factor, such as IGF-I, or the neutralization of an antagonist. Ideally, the targeting of an anabolic agent should be specific to bone to preclude non-skeletal unwanted side effects. Clinical trials are needed to determine the long-term effectiveness and safety of novel anabolic agents for the management of osteoporosis.

Maternal expectations about normal child development in 4 cultural groups.

Abstract: Objective: To determine whether expectations about normal infant and child development are different among mothers from 4 ethnocultural groups. Participants: Two hundred fifty-five mothers (90 Puerto Rican, 59 African American, 69 European American, 37 West Indian–Caribbean) whose children received health care at hospital-based pediatric clinics and private pediatricians' and family practitioners' offices. Design: Verbally administered questionnaire that included 25 questions in which mothers were asked to give their opinions about the age at which a normal child should begin to accomplish standard developmental milestones. Analysis: Responses (mean ages at which mothers expected children to attain the milestones) from each group were compared after controlling for age of mother, number of children, level of education, and socioeconomic status. Results: Significant differences among ethnic groups' responses were seen for 9 of 25 developmental milestones. Differences were mainly seen among personal and social milestones, and Puerto Rican mothers tended to expect children to attain these milestones at a later age than did other mothers. No differences in responses were seen between Spanish- and English-speaking Puerto Rican mothers. European-American mothers expected children to take first steps and become toilet trained at a later age. Conclusions: Developmental expectations differ among mothers from different ethnocultural groups. Many of these differences can be explained by underlying cultural beliefs and values and specific child-rearing practices. Clinicians should ask about maternal expectations during child health visits to interpret mothers' concerns and opinions about their children's development. Arch Pediatr Adolesc Med. 1997;151:1144-1150

Relaxation response-based yoga improves functioning in young children with autism: a pilot study.

Abstract: Objectives: The study objectives were to develop and objectively assess the therapeutic effect of a novel movement-based complementary and alternative medicine approach for children with a

Serum IGF-1 determines skeletal strength by regulating subperiosteal expansion and trait interactions

Abstract: Strong correlations between serum IGF-1 levels and fracture risk indicate that IGF-1 plays a critical role in regulating bone strength. However, the mechanism by which serum IGF-1 regulates bone structure and fracture resistance remains obscure and cannot be determined using conventional approaches. Previous analysis of adult liver-specific IGF-1–deficient (LID) mice, which exhibit 75% reductions in serum IGF-1 levels, showed reductions in periosteal circumference, femoral cross-sectional area, cortical thickness, and total volumetric BMD. Understanding the developmental sequences and the resultant anatomical changes that led to this adult phenotype is the key for understanding the complex relationship between serum IGF-1 levels and fracture risk. Here, we identified a unique developmental pattern of morphological and compositional traits that contribute to bone strength. We show that reduced bone strength associated with low levels of IGF-1 in serum (LID mice) result in impaired subperiosteal expansion combined with impaired endosteal apposition and lack of compensatory changes in mineralization throughout growth and aging. We show that serum IGF-1 affects cellular activity differently depending on the cortical surface. Last, we show that chronic reductions in serum IGF-1 indirectly affect bone strength through its effect on the marrow myeloid progenitor cell population. We conclude that serum IGF-1 not only regulates bone size, shape, and composition during ontogeny, but it plays a more fundamental role—that of regulating an individual's ability to adapt its bone structure to mechanical loads during growth and development.

Bone morphogenetic proteins induce gremlin, a protein that limits their activity in osteoblasts.

Abstract: Bone morphogenetic proteins (BMP) induce the differentiation of cells of the osteoblastic lineage and enhance the function of the osteoblast. Growth factor activity is regulated by binding proteins, and we previously showed that BMPs induce noggin, a glycoprotein that binds and blocks BMP action. Recently, additional BMP antagonists, such as gremlin, have been described, but there is no information about their expression or function in osteoblasts. We tested for the expression of gremlin and studied its induction by BMPs in cultures of osteoblast-enriched cells from 22-day-old fetal rat calvariae (Ob cells). BMP-2 caused a time- and dose-dependent increase in gremlin messenger RNA and polypeptide levels, as determined by Northern and Western blot analyses. The effects of BMP-2 on gremlin transcripts were independent of new protein synthesis. BMP-2 increased the rate of gremlin transcription as determined by nuclear run-on assays. Fibroblast growth factor-2 and platelet-derived growth factor BB also induce...