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Biomedical subjects

M C Shaffer

Publications and source records attributed to M C Shaffer.

6 recordsLinked to original sources

Human serum spreading factor: relationship to somatomedin B.

Human serum spreading factor (SF) is a blood glycoprotein that promotes the attachment and spreading of a variety of cell types in serum-free culture, as well as affecting migration, proliferation and differentiation of some cell types under appropriate conditions. The amino acids occupying 17 of the first 23 positions from the NH2-terminus of SF were determined, and this sequence was found to be identical to that reported for somatomedin B (SmB) by Fryklund and Sievertsson (FEBS Letters 87:55). Immunoassay of SF in plasma from subjects with conditions related to altered GH levels indicated that serum SF levels were not GH-responsive to any marked degree. No effect of purified SF was observed in a cell growth assay used previously to detect mitogenic activity in SmB preparations. These results support the conclusion that SF acts as a substratum molecule to elicit its biological effects in cell culture, and does not act in a manner similar to peptide growth factors. These data also are consistent with the conclusion of Heldin et al. (Science 213:1122) that the mitogenic activity of SmB preparations is derived from a contaminating factor, and is not due to SmB.

Amino Acid Sequence

Quantitation of spreading factor in human biologic fluids.

Spreading factor (SF) is a glycoprotein isolated from human plasma or serum that promotes attachment and spreading of a wide variety of mammalian cells in culture. Under appropriate conditions, this factor also affects cell proliferation and differentiation in vitro. An immunoassay employing a previously characterized monoclonal antibody to SF, with purified SF as a reference standard, was utilized to quantitate levels of SF in human plasma, serum, amniotic fluid, and urinary protein. Specific anti-SF monoclonal antibody-binding activities in individual samples of human serum were identical to specific anti-SF monoclonal antibody-binding activities in the plasma samples from which the sera were derived. Specific anti-SF monoclonal antibody-binding activity in plasma from adults, when compared with purified SF reference standards, represented an average of 4 micrograms of SF per mg plasma protein (range, 2.5 to 7 micrograms/mg). Specific anti-SF monoclonal antibody-binding activity in sera from fetal cord blood, infants, children, or adolescents was not significantly different from that of adults. Specific anti-SF monoclonal antibody-binding activities in amniotic fluid samples from pregnancies of 12 to 23 weeks' gestation were within the range observed in sera of adults. Anti-SF monoclonal antibody-binding activity in concentrated urinary protein, when compared with purified SF reference standards, represented a specific activity of 10.9 micrograms of SF per mg protein.

Adolescent

Does closed circuit television still apply? A utilization and management study.

A recent utilization study of the closed circuit television system conducted by the Visual Education Department, Medical College of Virginia Campus, Virginia Commonwealth University, revealed that most of the videotapes were played to the three major campus educational buildings. As a result of the study the university will continue CCTV service to classrooms and laboratories in these high-use buildings. However, in an effort to cut costs and manpower, TV self-service has been implemented or increased in three locations.

Academic Medical Centers

Management of a learning resource center: a seven-year study.

Data compiled over seven years present evidence that small-group or "cluster" carrels are successfully utilized by medical students in a learning resource center (LRC) and, therefore, should be considered to be an efficient method of managing space, software, and hardware. Three management concepts account for high utilization of an LRC operated as a service in support of a medical school curriculum. Of special importance is the interaction of LRC staff with faculty, which directly accounts for a collection relevant to the curriculum. The other management concepts are responsiveness to students and delivery of services that support production and distribution of print and audiovisual resources for student learning.

Audiovisual Aids

Profile, data, and management of two learning resource centers, 1970--1978.

Eight years' data have been collected in the operation of learning resource centers (LRCs) for medical and dental students at the Medical College of Virginia Campus, Virginia Commonwealth University. Data present evidence of high utilization of facilities and materials, including the successful use of small group cluster carrels. Management concepts and strategies to account for the data are identified and the LRC profile discussed for an understanding of how the strategies are implemented. These management concepts--responsiveness to students, interaction with faculty, and delivery of coordinated service--are transferable to other institutions and serve as guidlines for efficient management of LRC space, staff, equipment, and acquisition in support of medical and dental school curricula.

Libraries, Dental