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Biomedical subjects

A R Davis

Publications and source records attributed to A R Davis.

130 records · Page 8Linked to original sources
PubMedDate not supplied

Adenovirus-mediated BMP2 expression in human bone marrow stromal cells.

Recombinant adenoviral vectors have been shown to be potential new tools for a variety of musculoskeletal defects. Much emphasis in the field of orthopedic research has been placed on developing systems for the production of bone. This study aims to determine the necessary conditions for sustained production of high levels of active bone morphogenetic protein 2 (BMP2) using a recombinant adenovirus type 5 (Ad5BMP2) capable of eliciting BMP2 synthesis upon infection and to evaluate the consequences for osteoprogenitor cells. The results indicate that high levels (144 ng/ml) of BMP2 can be produced in non-osteoprogenitor cells (A549 cell line) by this method and the resultant protein appears to be three times more biologically active than the recombinant protein. Surprisingly, similar levels of BMP2 expression could not be achieved after transduction with Ad5BMP2 of either human bone marrow stromal cells or the mouse bone marrow stromal cell line W20-17. However, human bone marrow stromal cells cultured with 1 microM dexamethasone for four days, or further stimulated to become osteoblast-like cells with 50 microg/ml ascorbic acid, produced high levels of BMP2 upon Ad5BMP2 infection as compared to the undifferentiated cells. The increased production of BMP2 in adenovirus transduced cells following exposure to 1 microM dexamethasone was reduced if the cells were not given 50 microg/ml ascorbic acid. When bone marrow stromal cells were allowed to become confluent in culture prior to differentiation, BMP2 production in response to Ad5BMP2 infection was lost entirely. Furthermore, the increase in BMP2 synthesis seen during differentiation was greatly decreased when Ad5BMP2 was administered prior to dexamethasone treatment. In short, the efficiency of adenovirus mediated expression of BMP2 in bone marrow stromal cells appears to be dependent on the differentiation state of these cells.

Adenoviridae↗
PubMedDate not supplied

The Division of Nursing and its relationship to nurse practitioner education.

Nurses provide a large part of health care in the United States. Increasingly, among rural and underserved populations, urban and rural NPs and NMWs are taking the place of physicians who choose to specialize and to practice in metropolitan areas. Nurse practitioners and NMWs are well qualified to provide primary care for those with acute and chronic medical conditions, and to provide maternity care to the 95% of women whose pregnancies are normal and do not require specialist care by obstetricians. Since 1965, the DN, through its grant programs, has contributed to increasing the accessibility of health care in this country by helping to increase the supply of nurses in all specialties and improving the quality of graduates and undergraduates in nursing education. In the past 25 years, NPs and NMWs have proven their capability and worth. Federal support has helped to make these invaluable contributions possible.

Financing, Government↗