Matrix metalloproteinases (MMP) are zinc- or calcium-dependent proteinases involved in the normal maintenance of the extracellular matrix. When elevated, MMPs degrade matrix components contributing to tissue destruction in infected periodontal sites. The objectives of this study were two-fold: first to assess the ability of Porphyromonas gingivalis hemagglutinin B (HagB) to induce MMP responses in human myeloid dendritic cells and second, to assess the effect of host defense peptide human β defensin 3 (HBD3) to regulate and attenuate the MMP response of HagB treated dendritic cells. HBD3 (0.2, 2.0, or 20.0 µM) was given to primary dendritic cells pre-, co-, or post-treatment to HagB (0.02 or 0.2 µM). At 16 hours, MMP concentrations were determined. There were no significant differences in concentrations for all 3 replications for MMP-2 and -13. There were few significant differences in some of the replications for MMP-3, -7, and -9. There were more pronounced differences in MMP-1, -10, and -12 expression, which were significantly influenced by both the concentration of HBD3 and the timing of administration. Chemokine and cytokine responses were inversely related to MMP production. While MMP responses decreased in a dose related manner, chemokine responses were increased. Concentrations of MIP-1α were high and there were no differences in response to 0.02 and 0.2 M HagB with or without 20.0 M HBD3. However, the MIP-1β and TNFα response to 0.2 M HagB were only attenuated. HagB induces the production of MMPs in dendritic cells and treatment of dendritic cells with HBD3 can alter the profile of HagB-induced MMPs. Such a finding may have importance in the pathogenesis of periodontal disease.

International Telemetering Conference Proceedings / October 26-29, 1998 / Town & Country Resort Hotel and Convention Center, San Diego, California / As the performance of inexpensive commercial off-the-shelf (COTS) data storage devices continues to increase, the temptation to use them as the basis for data capture products for military and industrial applications becomes ever more compelling. For example, the Digital Linear Tape (DLT) format now offers a 270 Gigabits per cassette capacity at a sustained transfer rate of 40 Mbits/s – performance which would have cost tens or even hundreds of thousands of dollars per system just a few years ago. But to transplant such a device from its benign office habitat into a data capture product which will function reliably and consistently in a wide range of field and platform environments is an engineering task fully as difficult and complex as designing an environmentally robust recorder from scratch. This paper discusses the problems which typically have to be overcome; environmental protection, reliability, data integrity, power supplies, software issues, control and data interfacing, etc., citing practical examples of analog and digital DLT-based data recorders which are now entering service for telemetry, intelligence gathering, anti-submarine warfare and related applications