Sakir Unal

Cukurova University, Adhanah, Adana, Turkey

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Publications (43)83.06 Total impact

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    Plastic &amp Reconstructive Surgery 09/2009; 124(4S):72. · 3.54 Impact Factor
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    ABSTRACT: Microstomia reconstruction due to the presence a blunted oral commissure is a challenging task because it requires the restoration of intricately balanced distinct layers of tissues: the oral mucosa, the orbicular muscle, the vermilion border, and the perioral skin. The reliability of commissural reconstruction depends on 2 factors: the first one is breaking the contraction vectors causing blunting of the commissure and the second one is restoring the integrity of the oral sphincter. We have used local skin, vermilion border-muscle, and mucosa flaps designed in an asterisk pattern to break the contraction vectors and have paid certain attention to the restoration of the sphincter function of the circular muscle fibers. Our results have shown that, with the use of our asterisk design, a new commissure aesthetically comparable to the natural one can be created with the reestablishment of reliable oral competence.
    The Journal of craniofacial surgery 07/2009; 20(4):1256-9. · 0.81 Impact Factor
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    ABSTRACT: Temporomandibular dysfunction (TMD) has been established as a therapeutic challenge in the plastic and maxillofacial clinics. The current treatment recommendations for TMD include resting the jaw, soft diet, and pain medication with nonsteroidal analgesic agents. If conservative and noninvasive techniques do not work, more invasive techniques may be considered. The main goal of this study was to assess the safety and clinical utility of intraarticular injection of sodium hyaluronate for the treatment of symptoms associated with internal derangement of the temporomandibular joint (TMJ). In this prospective study, 40 TMJs of 33 patients who have TMD were treated with intraarticular sodium hyaluronate injections at weekly intervals for 3 weeks. Pre- and postinjection pain intensity, the presence of joint sounds, and interincisial distance were documented. The follow-up period was 12 months. There was a statistically significant reduction of pain intensity (P < 0.01) and joint sound (P < 0.05) in all patients. This study shows that intraarticular hyaluronic acid injection for the treatment of reducing and nonreducing disc displacement of TMJ is an effective and safe management.
    Annals of plastic surgery 04/2009; 62(3):265-7. · 1.29 Impact Factor
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    ABSTRACT: The role of vascularized bone allografting is not established in plastic and reconstructive surgery. The authors evaluated the contribution by osteopontin to fibrosis of allografted bone in a vascularized bone marrow transplantation model across a major histocompatibility complex barrier. Thirty-six transplantations were performed between Brown Norway (RT1 n) donors and Lewis (RT1 l) recipients divided into three groups: group 1, isografts between Lewis rats (n = 12); group 2, allografts without treatment (n = 8); and group 3, allografts under a 7-day alphabeta-T-cell receptor/cyclosporine protocol (n = 16). Flow cytometry assessed the presence of chimerism for donor major histocompatibility complex class I (RT1 n) antigens. Immunostaining was used to determine osteopontin expression in grafted and recipient bone, and histologic examination was used to assess bone architecture. Early engraftment of donor bone marrow cells (RT1 n) into the recipient bone marrow compartment was achieved at posttransplantation day 7. This corresponded with osteopontin expression restricted to the endosteum of trabecular bone and was associated with the preservation of hematopoietic cells within donor bone. Cell migration between donor and recipient bone marrow compartments was confirmed by the presence of recipient cells (RT1 l) within the allografted bone and donor-origin cells (RT1 n) within the recipient bone. At posttransplantation day 63, osteopontin expression within allografted bone was associated with allograft bone fibrosis and lack of hematopoietic properties. In contrast, the recipient's contralateral bone demonstrated a highly localized osteopontin expression pattern within the endosteum and active hematopoiesis with the presence of donor-specific (RT1 n) cells and correlated with chimerism maintenance. These results confirm that despite up-regulation of osteopontin expression and fibrosis of allografted bone, vascularized bone marrow transplantation resulted in efficient engraftment of donor cells into the recipient's bone marrow compartment, leading to chimerism maintenance.
    Plastic and reconstructive surgery 03/2009; 123(2 Suppl):34S-44S. · 2.74 Impact Factor
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    ABSTRACT: Vascularized bone marrow transplantation (VBMT) across a MHC barrier under a 7-day alphabeta-TCR mAb and CsA protocol facilitated multiple hematolymphoid chimerism via trafficking of the immature (CD90) bone marrow cells (BMC) between donor and recipient compartments. Early engraftment of donor BMC [BN(RT1(n))] into the recipient BM compartment [LEW(RT1(l))] was achieved at 1 week posttransplant and this was associated with active hematopoiesis within allografted bone and correlated with high chimerism in the hematolymphoid organs. Two-way trafficking between donor and recipient BM compartments was confirmed by the presence of recipient MHC class I cells (RT1(l)) within the allografted bone up to 3 weeks posttransplant. At 10 weeks posttransplant, decline of BMC viability in allografted bone corresponded with bone fibrosis and lack of hematopoiesis. In contrast, active hematopoiesis was present in the recipient bone as evidenced by the presence of donor-specific immature (CD90/RT1(n)) cells, which correlated with chimerism maintenance. Clonogenic activity of donor-origin cells (RT1(n)) engrafted into the host BM compartment was confirmed by colony-forming units (CFU) assay. These results confirm that hematolymphoid chimerism is developed early post-VBMT by T-cell lineage and despite allografted bone fibrosis chimerism maintenance is supported by B-cell linage and active hematopoiesis of donor-origin cells in the host BM compartment.
    American Journal of Transplantation 07/2008; 8(6):1163-76. · 6.19 Impact Factor
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    ABSTRACT: Composite tissue allografts (CTAs) consist of tissues derived from ectoderm and mesoderm and typically contain skin, fat, muscle, nerves, lymph nodes, bone, cartilage, ligaments, and bone marrow. Although “nonvital” to life, these tissues are structurally, functionally, and aes- important to patients who need func- tional restoration of musculoskeletal defects.
    12/2007: pages 11-21;
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    ABSTRACT: The reconstruction of large soft tissue defects in the orbital and maxillomalar region is a challenging task that necessitates the consideration of both functional and aesthetic outcomes. We used the frontal island skin flap in patients with full-thickness soft tissue defects of the periorbital and malar region. In the reconstruction of full-thickness defects of this particular region, the alternatives to this flap are other regional flaps or distant free flaps. Not every pedicled regional flap can be transferred to every defect and most of the time the application of distant free flaps increases the morbidity of the procedure. The surgeon must be capable of being able to select the most useful and comprehensive flap within a range of many alternatives. We present our experience in 10 patients with complex soft tissue defects in the maxillomalar and periorbital regions whose defects were reconstructed with frontal artery island skin flaps.
    Journal of Craniofacial Surgery 10/2007; 18(5):1108-13. · 0.69 Impact Factor
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    ABSTRACT: We compared the effects of intraosseous BMT with those of standard i.v. BMT on the efficacy on donor-cell engraftment into the BM and lymphoid organs across an MHC barrier in rats. Twenty-four intraosseous and 24 i.v. BMTs were performed from 48 ACI (RT1(a)) donors to 48 Lewis (RT1(l)) recipients. Each transplant group received either intraosseous or i.v. BMT. Groups I and II served as controls without immunosuppression (n=16); groups III and IV received cyclosporine monotherapy (n=16); and V and VI received alphabeta-TCR monoclonal antibody and cyclosporine A (alphabeta-TCR/CsA) for 7 days (n=16). In each group, four rats received 35 x 10(6) transplanted bone marrow cells (BMCs) and four received 70 x 10(6) cells. All animals survived without GVHD. Mean (+/-s.d.) donor-cell engraftment into BM of recipients after intraosseous BMT was 7.9% (+/-1.3%) in recipients receiving alphabeta-TCR-CsA and 70 x 10(6) BMCs, and 4.2% (+/-1.4%) in recipients after i.v. transplantation. The seeding efficacy of donor cells into lymphoid tissue was greater after intraosseous BMT and alphabeta-TCR-CsA than after standard i.v. transplantation. In our model, intraosseous BMT facilitated donor-cell engraftment under short-term immunodepletive alphabeta-TCR/CsA protocol, which resulted in a temporary state of immune unresponsiveness.
    Bone Marrow Transplantation 09/2007; 40(4):373-80. · 3.54 Impact Factor
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    ABSTRACT: Extensive craniomaxillofacial deformities including bone and soft-tissue defects are always challenging for reconstructive surgeons. The purpose of this study was to extend application of the face/scalp transplantation model in the rat by incorporation of the vascularized calvarial bone, based on the same vascular pedicle, as a new treatment option for extensive craniomaxillofacial deformities with large bone defects. Seven composite hemiface/calvaria transplantations were performed across major histocompatibility complex barrier between Lewis-Brown Norway and Lewis rats. Seven donor and seven recipient rats were used in this study. Hemicalvarial bone and face grafts were dissected on the same pedicle of the common carotid artery and jugular vein and were transplanted to the deepithelialized donor faces. All rats received tapered and continuous doses of cyclosporine A monotherapy. Evaluation methods included flap angiography, daily inspection, computed tomographic scan, and bone histology. Flap angiography demonstrated the vascular supply of the bone. The average survival time was 154 days. There were no signs of rejection and there was no flap loss noted at 220 days posttransplantation. Bone histology at days 7, 30, 63, and 100 after transplantation revealed viable bone at all time points, and computed tomographic scans taken at days 14, 30, and 100 revealed normal bones without resorption. For extensive face deformities involving large bone and soft-tissue defects, this new osteomusculocutaneous hemiface/calvaria flap model may serve to create new reconstructive options for covering during one surgical procedure.
    Plastic and reconstructive surgery 12/2006; 118(6):1321-7. · 2.74 Impact Factor
  • Plastic and reconstructive surgery 05/2006; 117(4):1365-7. · 2.74 Impact Factor
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    ABSTRACT: Reconstruction of facial defects in burn, trauma, and head-neck cancer patients is challenging. The lack of autogenous tissue availability and the need to match facial texture and color are major concerns. Anatomical dissections were performed to search for alternative sources for facial-scalp reconstructions in five cadavers. The composite facial-scalp flaps, radial forearm, anterolateral thigh, bipedicled deep inferior epigastric perforator, and bipedicled scapular-parascapular flaps were harvested. The total surface areas of the facial defects and alternative traditional flaps were measured. The mean surface area for combined facial-scalp flaps and facial flaps without scalp was 1192 +/- 38.2 cm and 675 +/- 22.3 cm, respectively. When compared with the total surface area of the facial-scalp flap, it was found that the radial forearm flap covered 13 +/- 2.58 percent, the anterolateral thigh flap 19 +/- 3.72 percent, the bipedicled deep inferior epigastric perforator flap 35 +/- 1.56 percent, and the bipedicled scapular-parascapular flap 48 +/- 4.64 percent of the defect, respectively. When measurements were taken for coverage of the facial defect without scalp, it was found that the radial forearm flap covered 24 +/- 4.0 percent, the anterolateral thigh flap 34 +/- 6.50 percent, the bipedicled deep inferior epigastric perforator flap 62 +/- 3.03 percent, and the bipedicled scapular-parascapular flap 84 +/- 8.30 percent of the defect, respectively. The authors' cadaver dissection confirmed that none of the conventional cutaneous autogenous flaps are able to cover total facial defects. Currently, the best option for reconstruction of the full facial defect is the autogenous bipedicled scapular-parascapular flap because of its large size and texture. However, perfect match of facial skin texture, pliability, and color can only be achieved by transplantation of the facial skin allograft from the human donor.
    Plastic and reconstructive surgery 04/2006; 117(3):864-72; discussion 873-5. · 2.74 Impact Factor
  • Plastic and reconstructive surgery 04/2006; 117(3):1062-4. · 2.74 Impact Factor
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    ABSTRACT: The authors have performed mock facial transplantation by harvesting total facial-scalp flaps from donors and transferring them to recipient cadavers. A total of 10 fresh human cadavers were dissected. In the donor, the authors have measured the time of facial-scalp flap harvesting, and the length of the arterial and venous pedicles and sensory nerves that were included in the facial flaps. In the recipient, the authors have evaluated the time of facial skin harvest as a monobloc full-thickness graft, the anchoring regions for the inset of the donor facial flaps, and the time sequences for the vascular pedicle anastomoses and nerve coaptations. In the donor cadaver, the mean harvesting time of the total facial-scalp flap harvest was 235.62 +/- 21.94 minutes. The mean length of the supraorbital, infraorbital, mental, and great auricular nerves was 1.5 +/- 0.15, 2.46 +/- 0.25, 3.02 +/- 0.31, and 6.11 +/- 0.42 cm, respectively. The mean length of the external carotid artery, the facial vein, and external jugular vein was 5 +/- 0.32, 3.15 +/- 0.32, and 5.78 +/- 0.5 cm, respectively. In the recipient cadaver, the mean harvesting time of facial skin as a monobloc full-thickness graft was 47.5 +/- 3.53 minutes. The mean time for the preparation of the arterial and venous pedicles and sensory nerves for the future anastomoses and coaptation was 30 +/- 0 minutes. The mean time for facial flap anchoring was 22.5 +/- 3.53 minutes. The total mean time of facial mock transplantation without vessels and nerve repair was 320 +/- 7.07 minutes (5 hours 20 minutes). Based on anatomical dissections in this cadaver study, the authors have estimated the time and sequence of facial flap harvest and inset to mimic the clinical scenario of the facial transplantation procedure.
    Plastic and reconstructive surgery 04/2006; 117(3):876-85; discussion 886-8. · 2.74 Impact Factor
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    ABSTRACT: Superficial basal cell carcinomas (BCC) comprise 9% to 11% of BCC, and are commonly found on the trunk or limbs. We report a case of a superficial BCC on the scalp that was misdiagnosed and treated as seborrhoeic dermatitis. Any erythematous plaque-type lesion of long duration must have superficial BCC considered in the differential diagnosis.
    Scandinavian Journal of Plastic and Reconstructive Surgery and Hand Surgery 02/2006; 40(1):54-6. · 0.94 Impact Factor
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    ABSTRACT: Severe middle vault deformity with disturbed nasal form and function is one of the most challenging procedures to correct in a secondary rhinoplasty. Reconstructing the deformity with autologous septal cartilage would be the primary choice of most surgeons, if it were always available. However in certain cases the lack of a sufficient quantity of autologous cartilage has forced surgeons to explore other viable options. This paper discusses our experience with the combined use of spreader and dorsal onlay grafts from various materials in the reconstruction of severe middle vault deformity in 110 patients. In follow up, (between 6 and 42 months; mean 21 months) all patients were noted to have improved in both aesthetics and function with no major complications noted. In summary, this study proposes that any engrafting material can be used safely when the proper surgical principals and technique are employed.
    Journal of Plastic Reconstructive & Aesthetic Surgery 02/2006; 59(4):409-16; discussion 417-8. · 1.44 Impact Factor
  • Biology of Blood and Marrow Transplantation 02/2006; 12(2):6-6. · 3.94 Impact Factor
  • Maria Siemionow, Sakir Unal
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    ABSTRACT: Recent advances in the field of reconstructive surgery and immunology resulted in increased interest in composite tissue allograft (CTA) transplantation. Up to date, more than 50 CTA transplants have been reported in humans. A significant number of experimental studies on CTA transplants under different protocols of tolerance-inducting strategies have been reported in small-animal models. There is however, a limited number of CTA transplants performed in nonhuman primates. To reach the ultimate clinical success in CTA transplantation, more experimental studies on tolerance induction in nonhuman primates are needed to apply these immunomodulatory protocols to CTA transplants in humans. In this review, strategies for tolerance induction in the nonhuman primate model in solid organ and CTA transplants are presented in 3 major categories: chimerism induction, T-cell depletion, and costimulatory receptor blockade.
    Annals of Plastic Surgery 12/2005; 55(5):545-53. · 1.38 Impact Factor
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    ABSTRACT: We have previously developed a composite total face-scalp allotransplantation model based on bilateral common carotid arteries (CCA) and external jugular veins. To decrease the mortality rates, different modifications of arterial anastomoses in the facial allograft recipients are presented. Eighteen full face-scalp allograft transplantations were performed across major histocompatibility (MHC) barriers between ACI (RT1) donors and Lewis (RT1) recipients. Bilateral CCA and bilateral external carotid arteries of the recipients were used as recipient vessels to vascularize the flap in 5 and 4 transplants, respectively. In 9 transplants, unilateral CCA of the recipients were used to vascularize the face/scalp flap. All the animals received CsA 16 mg/kg/d Sc, which was tapered over 4 weeks to 2 mg/kg/d. In transplants utilizing bilateral CCA, the survival rate of the animals was very short. Transplants in which unilateral CCA were used yielded 100% survivals over 200 days posttransplant. These modifications of arterial anastomoses have significantly improved survival of facial allograft recipients.
    Annals of Plastic Surgery 10/2005; 55(3):297-303. · 1.38 Impact Factor
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    ABSTRACT: The purpose of this study was to determine the effects of combined use of L-carnitine and vitamin C on partially burned skin flap in an experimental rat model. In the rat dorsal skin, a 10 x 3 cm flap was marked. The most distal 3 x 3 cm part was burned to full thickness. Twenty-four rats were randomized into four groups with 6 animals in each. Group 1 was simply followed up. Group 2 was given 0.5 mg/kg vitamin C per day for 7 days, group 3 100 mg/kg carnitine per day for 7 days, and group 4 both carnitine and vitamin C. On the eighth postoperative day, the animals were sacrificed and examined. The surviving and necrotic areas were determined by macroscopic examination and measured with a planimeter. The areas of flap necrosis were measured. The median surviving areas and areas of flap necrosis, respectively, of the groups were: group 1, 16.0 cm(2) and 14.0 cm(2); group 2, 18.25 cm(2) and 11.75 cm(2); group 3, 20.0 cm(2) and 10 cm(2) ; and group 4, 23.75 cm(2) and 6.25 cm(2). The surviving areas of the groups were found to be significantly different (p=0.000). The risk of ischemia-induced necrosis in flap attempts made in damaged tissues may be reduced by the combination of two promising agents, L-carnitine and vitamin C. L-carnitine appears to be the major contributing factor that reduces necrosis, and vitamin C an additive agent.
    Medical science monitor: international medical journal of experimental and clinical research 07/2005; 11(6):BR176-180. · 1.22 Impact Factor
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    ABSTRACT: This prospective study was performed to analyze the causes of infection-related skin-graft loss in a general population of plastic and reconstructive surgery patients. One hundred thirty-two patients who received either full- or split-thickness skin grafts to reconstruct soft-tissue defects were included. The tissue defects were grouped according to the cause as follows: vascular ulcers (9.2%), burns (14.5%), traumatic tissue defects (36.6%), and flap donor-site defects (39.7%). In all cases, the preoperative evaluation indicated an adequate wound-bed preparation. However, graft loss secondary to infection was recorded in 31 patients (23.5%). The microbiological cultures revealed Pseudomonas aeruginosa in 58.1% of the cases (P<0.05), followed by Staphylococcus aureus, Enterobacter, enterococci, and Acinetobacter; 58.3% of grafts in vascular ulcers, 47.4% of grafts in burns, 16.7% of grafts in traumatic-tissue defects; and 13.5% of grafts in donor-site defects were lost due to infection. Vascular ulcers and burns were more commonly associated with graft losses due to infection than other tissue defects (P<0.001). No correlation was found between the etiological cause of the defects and the microorganisms cultured. However, Pseudomonas infections were more fulminant and caused an increased reoperation rate 4.2 times (P<0.05). Full-thickness grafts were more resistant to infection than split-thickness grafts (P<0.05). Graft loss due to infection was also more common in grafts applied to the lower extremities or when performed at multiple sites. In conclusion, 23.7% of skin grafts were lost due to infection in a group of general plastic surgery patients. Infection-related graft loss was more commonly encountered in vascular ulcers and burn wounds, and the most common cause was Pseudomonas aeruginosa.
    Annals of Plastic Surgery 07/2005; 55(1):102-6. · 1.38 Impact Factor