Biomedical subjects

S Y Mak

Publications and source records attributed to S Y Mak.

2 recordsLinked to original sources

PubMed2000

An XML-Java system for HL7-based healthcare informatics.

Health-Level (HL) 7 message semantics allows effective functional implementation of Electronic Medical Record (EMR)--encompassing both clinical and administrative (i.e. demographic and financial) information--interchange systems, at the expense of complexity with respect the Protocol Data Unit (PDU) structure and the client-side application architecture. In this paper we feature the usage of the Extensible Markup Language (XML) document-object modelling and Java client-server connectivity towards the implementation of a Web-based system for EMR transaction processing. Our solution features an XML-based description of EMR templates, which are subsequently transcribed into a Hypertext Markup Language (HTML)-Javascript form. This allows client-side user interfaceability and server-side functionality--i.e. message validation, authentication and database connectivity--to be handled through standard Web client-server mechanisms, the primary assumption being availability of a browser capable of XML documents and the associated stylesheets. We assume usage of the Internet as the interchange medium, hence the necessity for authentication and data privacy mechanisms, both of which can be constructed using standard Java-based building blocks.

Computer Communication Networks↗

PubMed1996

Mature T cell reactivity altered by peptide agonist that induces positive selection.

Recent studies have investigated how defined peptides influence T cell development. Using a T cell receptor-transgenic beta2-microglobulin-deficient model, we have examined T cell maturation in fetal thymic organ cultures in the presence of various peptides containing single-alanine substitutions of the strong peptide agonist, p33. Cocultivation with the peptide A4Y, which contains an altered T cell contact residue, resulted in efficient positive selection. Several in vitro assays demonstrated that A4Y was a moderate agonist relative to p33. Although A4Y promoted positive selection over a wide concentration range, high doses of this peptide could not induce clonal deletion. Thymocytes maturing in the presence of A4Y were no longer able to respond to A4Y, but could proliferate against p33. These studies demonstrate that (a) peptides that induce efficient positive selection at high concentrations are not exclusively antagonists; (b) some agonists do not promote clonal deletion; (c) positive selection requires a unique T cell receptor-peptide-major histocompatibility complex interaction; and (d) interactions with selecting peptides during T cell ontogeny may define the functional reactivity of mature T cells.

Amino Acid Sequence↗