The effects of a single oral dose of nifedipine on part of the immune response in healthy humans has been investigated in terms of two different immune functions: T lymphocyte proliferation and NK activity. Both functions are known to require calcium ions. Ten healthy subjects were bled before and 30 min, and 4 and 24 h after receiving 10 mg nifedipine. Lymphocyte proliferation, both in mitogen-activated lymphocyte cultures, and in autologous and allogeneic mixed lymphocyte reactions, was significantly reduced (up to 48%) 30 min after drug administration and reverted to normal 4 h later. The inhibition could be attributed to reduction in IL2 production by the T cells isolated 30 min following the administration of nifedipine, since they normally express IL2-receptors. The addition of recombinant IL2 of 200 U.ml-1 to the cell cultures restored their responsiveness. NK activity was significantly reduced 30 min and 4 h after drug administration and returned to normal at the 24th h. This function was also restored by the addition of IL2. The data suggest that calcium channel blockers may inhibit, at least transiently, lymphocyte functions in vivo.

The increase in the availability of bandwidth for wireless links, network integration, and the computational power on fixed and mobile platforms at affordable costs allows nowadays for the handling of audio and video data, their quality making them suitable for medical application. These information streams can support both continuous monitoring and emergency situations. According to this scenario, the authors have developed and implemented the mobile communication system which is described in this paper. The system is based on ITU-T H.323 multimedia terminal recommendation, suitable for real-time data/video/audio and telemedical applications. The audio and video codecs, respectively, H.264 and G723.1, were implemented and optimized in order to obtain high performance on the system target processors. Offline media streaming storage and retrieval functionalities were supported by integrating a relational database in the hospital central system. The system is based on low-cost consumer technologies such as general packet radio service (GPRS) and wireless local area network (WLAN or WiFi) for lowband data/video transmission. Implementation and testing were carried out for medical emergency and telemedicine application. In this paper, the emergency case study is described.