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Prolonged life expectancy, life style and environmental changes have caused a changing disease pattern in developed countries towards an increase of degenerative and autoimmune diseases. Stem cells have become a promising tool for their treatment by promoting tissue repair and protection from immune-attack associated damage. Patient-derived autologous stem cells present a safe option for this treatment since these will not induce immune rejection and thus multiple treatments are possible without any risk for allogenic sensitization, which may arise from allogenic stem cell transplantations. Here we report the outcome of treatments with culture expanded human adipose-derived mesenchymal stem cells (hAdMSCs) of 10 patients with autoimmune associated tissue damage and exhausted therapeutic options, including autoimmune hearing loss, multiple sclerosis, polymyotitis, atopic dermatitis and rheumatoid arthritis. For treatment, we developed a standardized culture-expansion protocol for hAdMSCs from minimal amounts of fat tissue, providing sufficient number of cells for repetitive injections. High expansion efficiencies were routinely achieved from autoimmune patients and from elderly donors without measurable loss in safety profile, genetic stability, vitality and differentiation potency, migration and homing characteristics. Although the conclusions that can be drawn from the compassionate use treatments in terms of therapeutic efficacy are only preliminary, the data provide convincing evidence for safety and therapeutic properties of systemically administered AdMSC in human patients with no other treatment options. The authors believe that ex-vivo-expanded autologous AdMSCs provide a promising alternative for treating autoimmune diseases. Further clinical studies are needed that take into account the results obtained from case studies as those presented here.

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In this paper, we analyze t,he delay performance for a Markovian source transported over a wireless channel with timevarying error charact.erist.ics.To improve the reliability of the channel, the end points of the wireless link implement a selective-repeat (SR) ARQ error control protocol. We provide an approximate discrete-time analysis of the endto-end mean packet delay, which consists of transport and resequencing delays. The transport delay, in turn, consists of queueing, transmission/retransmission, and propagation delays. In contrast to previous studies, our analysis accommodates the inherent autocorrelations in both the input traffic and the channel state. Our approximation of the mean transport, delay is based on decoupling the dependence of the queueing behavior from the past channel conditions. The exact probability generating function (PGF) of the queue length under ideal SR ARQ is obtained and is combined with the retransmission delay to obtain the mean transport delay. For the resequencing delay, our analysis is performed under heavy-traffic assumptions, hence providing an upper bound on the act.ual mean resequencing delay. Numerical results and simulations indicate that our approximate analysis is sufficiently accurate for a wide range of parameter values.