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Biomedical subjects

E M Palmer

Publications and source records attributed to E M Palmer.

6 recordsLinked to original sources
PubMed1997

Human T helper cell differentiation is regulated by the combined action of cytokines and accessory cell-dependent costimulatory signals.

We have developed an in vitro differentiation model for human Th cells to study the role of cytokines and accessory cell-dependent costimulatory signals in this process. Peripheral blood-derived CD4+ "naive" (CD45RA+ RO-) T cells were stimulated in weekly intervals with immobilized anti-CD3 mAb, accessory cells, and exogenous cytokines, and were analyzed for cytokine secretion pattern. With the B cell line JY (B7-1+ B7-2+), as source of accessory cells, we could generate distinct Th subsets. Coculture with the combination of recombinant human (rh) IL-1beta and rhIL-6 gave rise to Th0-like cells, which secreted low levels of IFN-gamma and IL-5. The addition of rhIL-12 led to the generation of Th1-like cells, which secreted high levels of IL-2, IFN-gamma, TNF-alpha, and upon multiple stimulations, significant levels of IL-10. The presence of rhIL-4 induced Th2-like cells that secreted high levels of IL-5 and IL-13, but undetectable levels of IL-4. Only after stimulation with phorbol ester and calcium ionophore could these Th2-like cells be induced to secrete significant levels of IL-4, indicating distinct stimulatory requirements for the induction of IL-5 and IL-13 compared with IL-4. The B7-1-negative monocytic cell line U937 could only provide accessory cell-dependent costimulatory signals for the generation of Th1-like cells, while B7-1-transfected U937 cells acquired the capacity to provide costimulation for the generation of Th2-like cells. These results indicate a differential dependence on CD28-mediated costimulation for the generation of human Th1-like and Th2-like cells.

Anti-Inflammatory Agents↗
PubMed1994

Electronic document delivery using the Internet.

The Health Sciences Libraries Consortium (HSLC) was established in 1985 by thirteen founding member institutions in Pennsylvania and Delaware. In 1989, the Interlibrary Loan, Document Delivery, and Union List Task Force, appointed by the HSLC Board of Directors, successfully demonstrated the feasibility of supplying 94% of all interlibrary loan (ILL) photocopy requests in forty-eight hours or less by a network application of group 3-level memory telefacsimiles. However, the expenses associated with the telefacsimile operation and the limitations associated with network polling protocols challenged participants to seek new alternatives for ILL. In 1990, the HSLC introduced HSLC HealthNET, an online wide-area network linking eleven of the thirteen institutions and their resources while providing access to the Internet. The HSLC HealthNET additionally supports a centralized shared library system, several locally mounted databases, and consortiumwide electronic mail. In 1991, a project was initiated to evaluate Ariel software, pioneered by the Research Libraries Group (RLG), compared to the existing network application of group 3-level telefacsimiles. Factors identified as critical to Ariel's potential to replace the telefacsimile network were the proprietary software specifications for Internet access, the use of HSLC's existing wide-area network (WAN), and a hardware platform that was optimal for an ILL environment. This article describes the Ariel project history, the transition to Ariel from the telefacsimile network, evaluation of equipment features for processing efficiency, and operational issues affecting ILL policy.

Computer Communication Networks↗