Gelişigüzel kanlanan deri flebinin sağkalımına deri altı trombolitik, antikoagülan ve vazodilatatör ilaç uygulamasının etkileri

Rekonstrüktif cerrahide deri flebi uygulamaları halen en sık uygulanan cerrahi girisimlerdir. Flepteki nekrozun önlenmesinde çesitli medikal ajanlar kullanılmıstır. Kaudal bazlı sıçan sırt flebi modeli olusturulan 24 adet sıçan 4 gruba ayrıldı. Grup 1&#8217;de (n=6) flep kaldırıldı ve yerine iade edildi. Grup 2&#8217;de (n=6) cerrahiden hemen sonra, 1. ve 2. günde Clexane enjeksiyonu yapıldı. Grup 3&#8217;de (n=6) cerrahiden hemen sonra, 1. ve 2. günde Nitroderm yama yapıstırıldı. Grup 4&#8217;te (n=6) cerrahiden hemen sonra, 1. ve 2. günde Actilyse enjeksiyonu yapıldı. Cerrahi öncesinde, flep kaldırıldıktan hemen sonra, 3. ve 7. günde lazer doppler akımölçer ile flebin proksimal ve distal yarısında kan akım hızları ölçüldü. Cerrahi sonrası 3. günde ve 7. günde histolojik degerlendirme için proksimal ve distal kısımlardan biyopsi alındı. Postoperatif 7. günde flep nekroz alanları belirlenmek üzere fotograflandı Tüm bu bulgular incelendiginde nekroz oranları kontrol grubuna kıyasla diger gruplarda belirgin azalmıstı. Ancak bu azalma sadece Clexane grubunda istatistiksel olarak anlamlıydı (p<0,05). Lazer doppler akımölçer ile incelendiginde kan akımının tüm gruplarda cerrahi sonrasında giderek azaldıgı görüldü. Histolojik degerlendirme sonrası özellikle Nitroderm grubunda belirgin olmak üzere PECAM boyaması ile anjiyogenezin indüklendigi görüldü. Sonuç olarak sistemik kullanımı olan bu ilaçların deri altı uygulamalarının flep sagkalımını arttırdıgı düsünüldü.Skin flaps are the most common applications in reconstructive surgery. Various medications are used to improve flap survival. Caudally based dorsal flap model was applied to 24 rats in 4 groups. In Group 1 (n=6) flap was elevated and sutured. In Group 2 (n=6) Clexane was injected subcutaneously right after surgery at day 1 and day 2 postoperative respectively. In Group 3 (n=6) Nitroderm patch was applied right after surgery, day 1 and day 2 postoperatively. In Group 4 (n=6) Actilyse was injected subcutaneously right after surgery, day 1 and day 2 postoperatively. Blood flow was measured with laser doppler flowmetry from the proximal and distal halves of flap, four times, such as before surgery, right after surgery, day 3 and day 7 postoperatively. Histologic samples were taken from proximal and distal halves at day 3 and day 7 postoperatively. Photographs were taken to determine flap necrosis areas at day 7 postoperatively. Skin necrosis area was found less than control group in the medication groups, but only in Clexane group skin necrosis was significant statistically (p<0,05). Laser doppler flowmetry results showed gradual decrease in all groups with time, but results was not significant statistically. Histologic findings revealed induction of angiogenesis in all medication groups but Nitroderm group was more prominent. In conclusion medications which have systemic usage could be beneficial in improving flap survival when used subcutaneously

Treg-inducing microparticles promote donor-specific tolerance in experimental vascularized composite allotransplantation

For individuals who sustain devastating composite tissue loss, vascularized composite allotransplantation (VCA; e.g., hand and face transplantation) has the potential to restore appearance and function of the damaged tissues. As with solid organ transplantation, however, rejection must be controlled by multidrug systemic immunosuppression with substantial side effects. As an alternative therapeutic approach inspired by natural mechanisms the body uses to control inflammation, we developed a system to enrich regulatory T cells (Tregs) in an allograft. Microparticles were engineered to sustainably release TGF-β1, IL-2, and rapamycin, to induce Treg differentiation from naïve T cells. In a rat hindlimb VCA model, local administration of this Treg-inducing system, referred to as TRI-MP, prolonged allograft survival indefinitely without long-term systemic immunosuppression. TRI-MP treatment reduced expression of inflammatory mediators and enhanced expression of Treg-associated cytokines in allograft tissue. TRI-MP also enriched Treg and reduced inflammatory Th1 populations in allograft draining lymph nodes. This local immunotherapy imparted systemic donor-specific tolerance in otherwise immunocompetent rats, as evidenced by acceptance of secondary skin grafts from the hindlimb donor strain and rejection of skin grafts from a third-party donor strain. Ultimately, this therapeutic approach may reduce, or even eliminate, the need for systemic immunosuppression in VCA or solid organ transplantation