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1.
Pharmaceutics ; 15(10)2023 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-37896130

RESUMO

Despite long-term immunosuppression, organ transplant recipients face the risk of immune rejection and graft loss. Tacrolimus (TAC, FK506, Prograf®) is an FDA-approved keystone immunosuppressant for preventing transplant rejection. However, it undergoes extensive first-pass metabolism and has a narrow therapeutic window, which leads to erratic bioavailability and toxicity. Local delivery of TAC directly into the graft, instead of systemic delivery, can improve safety, efficacy, and tolerability. Macrophages have emerged as promising therapeutic targets as their increased levels correlate with an increased risk of organ rejection and a poor prognosis post-transplantation. Here, we present a locally injectable drug delivery platform for macrophages, where TAC is incorporated into a colloidally stable nanoemulsion and then formulated as a reversibly thermoresponsive, pluronic-based nanoemulgel (NEG). This novel formulation is designed to undergo a sol-to-gel transition at physiological temperature to sustain TAC release in situ at the site of local application. We also show that TAC-NEG mitigates the release of proinflammatory cytokines and nitric oxide from lipopolysaccharide (LPS)-activated macrophages. To the best of our knowledge, this is the first TAC-loaded nanoemulgel with demonstrated anti-inflammatory effects on macrophages in vitro.

2.
Curr Opin Organ Transplant ; 28(6): 431-439, 2023 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-37800652

RESUMO

PURPOSE OF REVIEW: Vascularized composite allotransplantation (VCA) has become a clinical reality in the past two decades. However, its routine clinical applications are limited by the risk of acute rejection, and the side effects of the lifelong immunosuppression. Therefore, there is a need for new protocols to induce tolerance and extend VCA survival. Cell- based therapies have emerged as an attractive strategy for tolerance induction in VCA. This manuscript reviews the current strategies and applications of cell-based therapies for tolerance induction in VCA. RECENT FINDINGS: Cellular therapies, including the application of bone marrow cells (BMC), mesenchymal stem cells (MSC), adipose stem cells, regulatory T cells (Treg) cells, dendritic cells and donor recipient chimeric cells (DRCC) show promising potential as a strategy to induce tolerance in VCA. Ongoing basic science research aims to provide insights into the mechanisms of action, homing, functional specialization and standardization of these cellular therapies. Additionally, translational preclinical and clinical studies are underway, showing encouraging outcomes. SUMMARY: Cellular therapies hold great potential and are supported by preclinical studies and clinical trials demonstrating safety and efficacy. However, further research is needed to develop novel cell-based immunosuppressive protocol for VCA.


Assuntos
Alotransplante de Tecidos Compostos Vascularizados , Humanos , Alotransplante de Tecidos Compostos Vascularizados/efeitos adversos , Alotransplante de Tecidos Compostos Vascularizados/métodos , Imunomodulação , Terapia de Imunossupressão/métodos , Tolerância Imunológica , Imunossupressores , Rejeição de Enxerto/prevenção & controle
3.
Ann Plast Surg ; 91(5): 571-577, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37405861

RESUMO

ABSTRACT: The skeletal integrity of the foot is as important as the soft tissue coverage of the foot. In this article, we present reconstruction of arches of foot with free fibula flap. Three patients with composite foot defects underwent reconstruction a with vascularized fibula flap. Free fibula flap was used to reconstruct the transverse arch in 2 cases and longitudinal arch in 1 case. The mean follow-up period was 3.2 years. Functional outcome was evaluated with 3-dimensional motion analyses at 12 months postoperatively. No early or late complications were encountered, and all patients were satisfied with both cosmetic appearance and functional aspects of their foot. Fibular bone showed a very healthy course without any fracture, resorption, extrusion, or migration. Three-dimensional motion analyses revealed acceptable gait capability in all cases showing successful restoration of the foot arches. As a conclusion, osteocutaneous free fibula flap can provide functional and durable reconstruction of longitudinal and transverse arches of the foot, especially if preservation of the length or the width of the foot is desired.

4.
Microsurgery ; 43(8): 823-830, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37354047

RESUMO

BACKGROUND: The time between procurement and transplantation of composite tissues, especially regarding the limited donor pool, is a challenge effecting the outcomes of the transplantation. Current preservation techniques mainly include either cold preservation with a solution or machine perfusion using blood or certain oxygen-carrying solutions. However, none enables preservation beyond 24 h. Increasing this time to several days will provide better usage of the donor pool, safer transplantation of VCA with significant muscle content, and gives time to stabilize a patient before long surgical procedures. Herein, we described a novel strategy of xenopreservation (preservation via xenotransplantation) to preserve composite tissues for 7 days, followed by staged transplantation. MATERIALS AND METHODS: We used two concordant species, female Sprague Dawley rats (n = 10) and female CF-1 mice (n = 10) in this study. Four of pair of animals are used for anatomical study. The groin flap of the rat was used as a xenograft and xenotransplanted to the neck area of the carrier mouse. Cyclosporine (CsA) was administered used as immunosuppressant. After 7 days of preservation on the mouse neck, xenotransplanted groin flap (called xenopreserved flap) was re-harvested, skin and vessels samples were collected for histopathological evaluation, and the xenopreserved flap was transplanted to the donor rat's opposite groin area. Anastomoses were performed between the flap's pedicle and the femoral vessels. Clinical observation regarding inflammation and tissue perfusion of the xenopreserved flap was monitored daily. Fifteen days after the second surgical procedure, the rats were euthanized, and skin and vessel samples were collected. Histologic evaluation, including inflammatory cell numbers, was performed. Wilcoxon test was used to compare the changes in inflammation severity and p < .05 was set for statistical significance. RESULTS: All xenopreserved groin flaps except one survived. Mean lymphocyte count before the second operation (at the end of the xenopreservation procedure) was 20,22 ± 0.44 and reduced to 13,14 ± 0.47 at the end of 15 days, and the difference was statistically significant (p < .05). CONCLUSION: This proof-of-concept study with preliminary results showed that xenotransplantation might be a novel strategy for preservation of VCA for a certain period of time. However, additional translational studies are needed to modulate the tissue changes following xenopreservation.


Assuntos
Pele , Retalhos Cirúrgicos , Humanos , Ratos , Feminino , Animais , Camundongos , Ratos Sprague-Dawley , Modelos Animais de Doenças , Inflamação
5.
Front Immunol ; 14: 1151824, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37251389

RESUMO

Introduction: Vascularized composite allotransplantation (VCA), with nerve repair/coaptation (NR) and tacrolimus (TAC) immunosuppressive therapy, is used to repair devastating traumatic injuries but is often complicated by inflammation spanning multiple tissues. We identified the parallel upregulation of transcriptional pathways involving chemokine signaling, T-cell receptor signaling, Th17, Th1, and Th2 pathways in skin and nerve tissue in complete VCA rejection compared to baseline in 7 human hand transplants and defined increasing complexity of protein-level dynamic networks involving chemokine, Th1, and Th17 pathways as a function of rejection severity in 5 of these patients. We next hypothesized that neural mechanisms may regulate the complex spatiotemporal evolution of rejection-associated inflammation post-VCA. Methods: For mechanistic and ethical reasons, protein-level inflammatory mediators in tissues from Lewis rats (8 per group) receiving either syngeneic (Lewis) or allogeneic (Brown-Norway) orthotopic hind limb transplants in combination with TAC, with and without sciatic NR, were compared to human hand transplant samples using computational methods. Results: In cross-correlation analyses of these mediators, VCA tissues from human hand transplants (which included NR) were most similar to those from rats undergoing VCA + NR. Based on dynamic hypergraph analyses, NR following either syngeneic or allogeneic transplantation in rats was associated with greater trans-compartmental localization of early inflammatory mediators vs. no-NR, and impaired downregulation of mediators including IL-17A at later times. Discussion: Thus, NR, while considered necessary for restoring graft function, may also result in dysregulated and mis-compartmentalized inflammation post-VCA and therefore necessitate mitigation strategies. Our novel computational pipeline may also yield translational, spatiotemporal insights in other contexts.


Assuntos
Alotransplante de Tecidos Compostos Vascularizados , Ratos , Humanos , Animais , Ratos Endogâmicos Lew , Alotransplante de Tecidos Compostos Vascularizados/efeitos adversos , Alotransplante de Tecidos Compostos Vascularizados/métodos , Tacrolimo/uso terapêutico , Inflamação , Mediadores da Inflamação , Nervos Periféricos
6.
Eplasty ; 23: e71, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38229968

RESUMO

Background: Gunshot wounds of the hand are challenging, as these injuries include bones, tendons neurovascular structures, and soft tissue. The osteocutaneous fibula flap has shown to be an excellent option for treating the composite defects, including bone and soft tissue. In this study, reconstructions of gunshot injuries of the metacarpal bones with a fibular flap are presented. Methods: Six patients with gunshot injuries to the hand were treated with free fibula flap. All patients had composite defects reconstructed with osteocutaneous fibula flap. Because of the size mismatch between fibula and metacarpal bone, a longitudinally split fibula was used in 2 patients. In 1 patient, the flap was used in a double-barrel fashion to reconstruct 2 metacarpal bone losses. Tendon repairs were performed either primarily or with tendon graft. All patients received hand rehabilitation. Hand function of the patients was evaluated by grip and pinch strength tests and Jebsen hand function test. Results: All flaps survived with no major postoperative complications. The mean follow-up period was 18 months. Web releasing and an arthrodesis procedure was performed in 1 patient, and tenolysis was performed in 2 others. All flaps adapted well to the recipient area. With respect to routine daily activities, overall hand function measured by grip and pinch strength tests and Jebsen hand function test was considered satisfactory in all patients. Conclusions: The fibular flap is a good alternative for reconstruction of the injured hand with composite defects, including metacarpal bone and soft tissue. It can be used longitudinally or transversely. Osteotomies can be performed to obtain split fibular flap or double-barrel fibular flap according to the bone defect.

7.
Transpl Immunol ; 75: 101696, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35987329

RESUMO

BACKGROUND: We evaluated the outcome of vertical rectus abdominus myocutaneous flap (VRAM) allotransplantation in a mini-pig model, using a combined co-stimulation blockade (Co-SB) and mechanistic target of rapamycin inhibition (mTORi)-based regimen, with or without preceding calcineurin inhibition (CNI). MATERIALS AND METHODS: VRAM allotransplants were performed between SLA-mismatched MGH miniature swine. Group A (n = 2) was treated continuously with the mTOR inhibitor rapamycin from day -1 in combination with the Co-SB agent cytotoxic T lymphocyte antigen 4-Ig (CTLA4-Ig) from post-operative day (POD) 0. In group B (n = 3), animals received tacrolimus daily from POD 0 to POD 13, followed by rapamycin daily from POD 7 and CTLA4-Ig weekly from POD 7-28. Graft rejection was determined by Banff criteria and host cellular and humoral immunity monitored. RESULTS: In group A, allografts developed grade-I acute rejection by POD 2 and POD 7, and reached grade-IV by POD 17 and POD 20, respectively. By contrast, in group B, two allografts demonstrated grade-I rejection on POD 30 and grade-IV on POD 74, while the third exhibited grade-I rejection starting on POD 50, though this animal had to be euthanized on POD 58 due to Pneumocystis jirovecii infection. Time-to-event incidence of grade-I rejection was significantly lower in group A compared to group B. During the first 3 weeks post-transplant, no significant differences in anti-donor immunity were observed between the groups. CONCLUSION: A short course of CNI, followed by combined Co-SB and mTORi significantly delays acute rejection of VRAM allografts in SLA-mismatched miniature swine.


Assuntos
Aloenxertos Compostos , Tacrolimo , Animais , Suínos , Tacrolimo/uso terapêutico , Porco Miniatura , Sirolimo/uso terapêutico , Sobrevivência de Enxerto , Abatacepte/uso terapêutico , Rejeição de Enxerto , Imunossupressores/uso terapêutico , Imunossupressores/farmacologia
8.
Front Bioeng Biotechnol ; 10: 863969, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35573254

RESUMO

The use of autografted nerve in surgical repair of peripheral nerve injuries (PNI) is severely limited due to donor site morbidity and restricted tissue availability. As an alternative, synthetic nerve guidance channels (NGCs) are available on the market for surgical nerve repair, but they fail to promote nerve regeneration across larger critical gap nerve injuries. Therefore, such injuries remain unaddressed, result in poor healing outcomes and are a limiting factor in limb reconstruction and transplantation. On the other hand, a myriad of advanced biomaterial strategies to address critical nerve injuries are proposed in preclinical literature but only few of those have found their way into clinical practice. The design of synthetic nerve grafts should follow rational criteria and make use of a combination of bioinstructive cues to actively promote nerve regeneration. To identify the most promising NGC designs for translation into applicable products, thorough mode of action studies, standardized readouts and validation in large animals are needed. We identify design criteria for NGC fabrication according to the current state of research, give a broad overview of bioactive and functionalized biomaterials and highlight emerging composite implant strategies using therapeutic cells, soluble factors, structural features and intrinsically conductive substrates. Finally, we discuss translational progress in bioartificial conduits for nerve repair from the surgeon's perspective and give an outlook toward future challenges in the field.

9.
J Control Release ; 330: 889-897, 2021 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-33157189

RESUMO

Delivering localized treatment to the paranasal sinuses for diseases such as chronic rhinosinusitis (CRS) is particularly challenging because of the small natural openings leading from the sinuses that can be further obstructed by presence of inflammation. As such, oral steroids, topical nasal sprays or irrigation, and surgery can be utilized to treat persistent sinonasal inflammation, but there exists a need for post-operative options for long-term steroid delivery to prevent disease recurrence. In the present study, a Thermogel, Extended-release Microsphere-based-delivery to the Paranasal Sinuses (TEMPS) is developed with the corticosteroid mometasone furoate. Specifically, the bioactive steroid is released for 4 weeks from poly(lactic-co-glycolic acid) (PLGA) microspheres embedded in a poly(N-isopropylacrylamide) (p-NIPAAm)-based hydrogel. The temperature-responsive system undergoes a reversible sol-gel transition at 34-35 °C such that it can be applied as a liquid at ambient temperature, conforming to the sinonasal epithelium as it gels. In a rabbit model of CRS, TEMPS was maintained in rabbit sinuses and effectively reduced sinonasal inflammation as characterized by micro-computed tomography and histopathology analysis. Ultimately, the combination of controlled release microspheres with a thermoresponsive hydrogel provides flexibility for encapsulating therapeutics in a reversible and conforming system for localized delivery to the sinuses.


Assuntos
Seios Paranasais , Rinite , Corticosteroides , Animais , Doença Crônica , Hidrogéis , Coelhos , Microtomografia por Raio-X
11.
Sci Adv ; 6(11): eaax8429, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32201714

RESUMO

Vascularized composite allotransplantation (VCA) encompasses face and limb transplantation, but as with organ transplantation, it requires lifelong regimens of immunosuppressive drugs to prevent rejection. To achieve donor-specific immune tolerance and reduce the need for systemic immunosuppression, we developed a synthetic drug delivery system that mimics a strategy our bodies naturally use to recruit regulatory T cells (Treg) to suppress inflammation. Specifically, a microparticle-based system engineered to release the Treg-recruiting chemokine CCL22 was used in a rodent hindlimb VCA model. These "Recruitment-MP" prolonged hindlimb allograft survival indefinitely (>200 days) and promoted donor-specific tolerance. Recruitment-MP treatment enriched Treg populations in allograft skin and draining lymph nodes and enhanced Treg function without affecting the proliferative capacity of conventional T cells. With implications for clinical translation, synthetic human CCL22 induced preferential migration of human Treg in vitro. Collectively, these results suggest that Recruitment-MP promote donor-specific immune tolerance via local enrichment of suppressive Treg.


Assuntos
Quimiotaxia de Leucócito/imunologia , Tolerância Imunológica , Linfócitos T Reguladores/imunologia , Alotransplante de Tecidos Compostos Vascularizados , Aloenxertos , Animais , Citocinas/genética , Citocinas/metabolismo , Epitopos , Expressão Gênica , Rejeição de Enxerto/imunologia , Sobrevivência de Enxerto/imunologia , Humanos , Imunomodulação , Mediadores da Inflamação/metabolismo , Ratos , Transplante de Pele , Linfócitos T Reguladores/metabolismo , Doadores de Tecidos , Imunologia de Transplantes
12.
Microsurgery ; 40(5): 576-584, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31904149

RESUMO

INTRODUCTION: Research on tolerance has proven that development of donor-specific chimerism (DSC) may accompany tolerance induction in vascularized composite allotransplantation (VCA). In this study, we aimed to determine the effect of thymus transplantation on the induction of DSC in rat VCA model of osseomusculocutaneous sternum (OMCS) and osseomusculocutaneous sternum and thymus (OMCST) allotransplantation. MATERIALS AND METHODS: A total of 20 Lewis-Brown Norway and Lewis rats, 5-6 weeks old, weighting between 120 and 150 g, were used in the study. OMCS (n = 5) and OMCST (n = 5) allografts were harvested from Lewis-Brown Norway donors (RT1l + n ) based on the common carotid artery and external jugular vein, and a heterotopic transplantation was performed to the inguinal region of the Lewis (RT1l ) recipients under cyclosporine A monotherapy (16 mg/kg) protocol tapered to 2 mg/kg and maintained for the duration of the study. The peripheral blood chimerism levels (T-cell, B-cell, and monocyte/granulocyte/dendritic cell-MGDC populations) were evaluated at days 7, 14, 35, 63, 100, and 150 posttransplant by flow cytometry. At Day 150, thymus, spleen, and liver samples were assessed by polymerase chain reaction (PCR) in the presence of DSC. RESULTS: Total chimerism level increased in both OMCST and OMCS groups at all time points. At 150 days posttransplant, chimerism in OMCST group was significantly higher (12.91 ± 0.16%) than that in OMCS group (8.89 ± 0.53%%, p < .01), and PCR confirmed the presence of donor-derived cells in the liver and spleen of all OMCST recipients and in one liver sample and two spleen samples in OMCS recipients without thymus transplant. CONCLUSIONS: This study confirmed the direct effects of thymus transplantation on the induction and maintenance of DSC in T-cell, B-cell, and MGDC populations. These results confirm correlation between thymus transplantation and DSC induction.


Assuntos
Quimerismo , Músculos Peitorais , Animais , Sobrevivência de Enxerto , Ratos , Ratos Endogâmicos Lew , Costelas , Transplante de Pele , Esterno/cirurgia , Quimeras de Transplante
13.
Proc Natl Acad Sci U S A ; 116(51): 25784-25789, 2019 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-31792185

RESUMO

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-ß1, 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.


Assuntos
Micropartículas Derivadas de Células/metabolismo , Terapia de Imunossupressão/métodos , Linfócitos T Reguladores/citologia , Tolerância ao Transplante/fisiologia , Alotransplante de Tecidos Compostos Vascularizados/métodos , Animais , Citocinas/metabolismo , Sistemas de Liberação de Medicamentos , Imunossupressores/metabolismo , Ratos
14.
Curr Opin Organ Transplant ; 24(6): 726-732, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31689262

RESUMO

PURPOSE OF REVIEW: The advent of clinical vascularized composite allotransplantation (VCA), offers hope for whole eye transplantation (WET) in patients with devastating vison loss that fails or defies current treatment options. Optic nerve regeneration and reintegration remain the overarching hurdles to WET. However, the realization of WET may indeed be limited by our lack of understanding of the singular immunological features of the eye as pertinent to graft survival and functional vision restoration in the setting of transplantation. RECENT FINDINGS: Like other VCA, such as the hand or face, the eye includes multiple tissues with distinct embryonic lineage and differential antigenicity. The ultimate goal of vision restoration through WET requires optimal immune modulation of the graft for successful optic nerve regeneration. Our team is exploring barriers to our understanding of the immunology of the eye in the context of WET including the role of immune privilege and lymphatic drainage on rejection, as well as the effects ischemia, reperfusion injury and rejection on optic nerve regeneration. SUMMARY: Elucidation of the unique immunological responses in the eye and adnexa after WET will provide foundational clues that will help inform therapies that prevent immune rejection without hindering optic nerve regeneration or reintegration.


Assuntos
Olho/imunologia , Olho/transplante , Sobrevivência de Enxerto/imunologia , Humanos
15.
J Plast Reconstr Aesthet Surg ; 72(10): 1640-1650, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31377202

RESUMO

INTRODUCTION: Whole eye transplantation (WET) holds promise for vision restoration in devastating/disabling visual loss (congenital or traumatic) not amenable to surgical or neuroprosthetic treatment options. The eye includes multiple tissues with distinct embryonic lineage and differential antigenicity. Anatomically and immunologically, the eye is unique due to its avascular (cornea) and highly vascular (retina) components. Our goal was to establish technical feasibility, demonstrate graft viability, and evaluate histologic changes in ocular tissues/adnexae in a novel experimental model of WET that included globe, adnexal, optic nerve (ON), and periorbital soft tissues. METHODS: Outbred Sprague-Dawley rats (n = 5) received heterotopic vascularized WET from donors. Each WET included the entire globe, adnexa, ON, and periorbital soft tissues supplied by the common carotid artery and external jugular vein. Viability and perfusion were confirmed by clinical examination, angiography and magnetic resonance imaging (MRI). Globe, adnexal, and periorbital tissues were analyzed for histopathologic changes, and the ON was examined for neuro-regeneration at study endpoint (30 days) or Banff Grade 3 rejection in the periorbital skin (whichever was earlier). RESULTS: Gross examination confirmed transplant viability and corneal transparency. Average operative duration was 64.0 ±â€¯5.8 min. Average ischemia time was 26.0 ±â€¯4.2 min. MRI revealed loss of globe volume by 36.0 ±â€¯2.8% after transplantation. Histopathology of globe and adnexal tissues showed unique and differential patterns of inflammatory cell infiltration. The ON revealed a neurodegeneration pattern. CONCLUSION: The present study is the first in the literature to establish an experimental model of WET. This model holds significant potential in investigating mechanistic pathways, monitoring strategies or developing management approaches involving ocular viability, immune rejection, and ON regeneration after WET.


Assuntos
Olho/transplante , Procedimentos Cirúrgicos Oftalmológicos/métodos , Transplante de Órgãos/métodos , Animais , Estudos de Viabilidade , Rejeição de Enxerto , Sobrevivência de Enxerto , Imageamento por Ressonância Magnética/métodos , Masculino , Modelos Teóricos , Procedimentos Cirúrgicos Oftalmológicos/efeitos adversos , Ratos , Ratos Sprague-Dawley , Medição de Risco , Sensibilidade e Especificidade
17.
Plast Reconstr Surg ; 141(4): 1011-1018, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29595735

RESUMO

BACKGROUND: Vascularized composite allotransplantation offers a new hope for restoration of orbital content and perhaps vision. The aim of this study was to introduce a new composite eyeball-periorbital transplantation model in fresh cadavers in preparation for composite eyeball allotransplantation in humans. METHODS: The composite eyeball-periorbital transplantation flap borders included the inferior border, outlined by the infraorbital rim; the medial border, created by the nasal dorsum; the lateral border, created by the lateral orbital rim; and the superior border, created by the superior part of the eyebrow. The pedicle of the flap included the facial artery, superficial temporal artery, and external jugular vein. The skin and subcutaneous tissues of the periorbital region were dissected and the bony tissue was reached. A coronal incision was performed and the frontal lobe of the brain was reached by means of frontal osteotomy. Ophthalmic and oculomotor nerves were also included in the flap. After a "box osteotomy" around the orbit, the dissection was completed. Methylene blue and indocyanine green injection (SPY Elite System) was performed to show the integrity of the vascular territories after facial flap harvest. RESULTS: Adequate venous return was observed within the flap after methylene blue dye injection. Laser-assisted indocyanine green angiography identified a well-defined vascular network within the entire composite eyeball-periorbital transplantation flap. CONCLUSIONS: For the first time, a novel composite eyeball-periorbital transplantation model in human cadavers was introduced. Good perfusion of the flap confirmed the feasibility of composite eyeball-periorbital transplantation in the clinical setting. Although harvesting of the flap is challenging, it introduces a new option for reconstruction of the periorbital region including the eyeball.


Assuntos
Olho/transplante , Órbita/transplante , Alotransplante de Tecidos Compostos Vascularizados/métodos , Idoso , Idoso de 80 Anos ou mais , Olho/irrigação sanguínea , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Órbita/irrigação sanguínea
18.
J Foot Ankle Surg ; 57(3): 627-631, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29284573

RESUMO

The heel comprises the epidermis, minimal subcutaneous tissue, a dense septum, and the calcaneus. Injury to any of these structures can impair the ability to walk. The soft tissue or calcaneal bone can be injured by trauma. Injuries incurred in war are usually high-energy traumas caused by weapons such as rifles, rockets, and land mines. Such injuries can be life threatening and involve the loss of tissue, including skin, soft tissue, bone, and neurovascular tissue. Two main treatment protocols are used for such injuries with large tissue defects: amputation and reconstruction. We describe a reconstruction with an osteomyocutaneous fibular flap for a heel injury. At the 2-year follow-up point, the patient had 30% loss of ankle range of motion. The visual analog scale score had dramatically decreased from 8 to 1, and the patient was satisfied with the result. In conclusion, patients with significant problems such as infection, pain, and anatomic deterioration of the calcaneus can be successfully treated using an osteomyocutaneous fibular flap in a single surgery.


Assuntos
Traumatismos por Explosões/cirurgia , Traumatismos do Pé/cirurgia , Retalho Miocutâneo/transplante , Osteomielite/cirurgia , Procedimentos de Cirurgia Plástica/métodos , Adulto , Traumatismos por Explosões/complicações , Traumatismos por Explosões/diagnóstico , Transplante Ósseo/métodos , Fíbula/cirurgia , Seguimentos , Traumatismos do Pé/diagnóstico , Calcanhar/lesões , Calcanhar/cirurgia , Humanos , Escala de Gravidade do Ferimento , Imageamento por Ressonância Magnética/métodos , Masculino , Militares , Osteomielite/etiologia , Osteomielite/fisiopatologia , Medição de Risco , Retalhos Cirúrgicos/transplante , Resultado do Tratamento , Cicatrização/fisiologia
19.
Turk J Med Sci ; 47(3): 861-867, 2017 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-28618735

RESUMO

BACKGROUND/AIM: The pedicled transverse rectus abdominis myocutaneous (TRAM) flap remains widely used as a breast reconstruction technique. The bipedicled TRAM flap is not as preferable as it was formerly, mainly because of its donor site complications. However, in a number of situations, a bipedicled TRAM flap may be the only alternative. Therefore, a three-layer primary closure technique used with bipedicled TRAM flap breast reconstructions that can avoid donor site complications without using a mesh is presented. MATERIALS AND METHODS: A retrospective study was performed that included patients who underwent bipedicled TRAM flap breast reconstruction with the three-layer primary closure technique. Between 2000 and 2015, 124 breast reconstruction patients were reviewed for donor site morbidity. RESULTS: During the 15-year study period, 106 patients had conventional bipedicled TRAM flaps and 18 had bipedicled TRAM flaps with a surgical delay procedure. For all groups, none of the patients developed abdominal wall hernia, but three patients had bulging. Partial flap loss was the most common flap complication, present in 6 flaps (4.8%). CONCLUSION: The suturing technique studied provided abdominal wall closure without the use of a mesh even when utilizing a bilateral pedicle with very low complication rates.


Assuntos
Técnicas de Fechamento de Ferimentos Abdominais , Mamoplastia , Retalhos Cirúrgicos/cirurgia , Técnicas de Fechamento de Ferimentos Abdominais/efeitos adversos , Técnicas de Fechamento de Ferimentos Abdominais/estatística & dados numéricos , Adulto , Feminino , Hérnia Abdominal , Humanos , Mamoplastia/efeitos adversos , Mamoplastia/métodos , Mamoplastia/estatística & dados numéricos , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Estudos Retrospectivos
20.
Clin Plast Surg ; 44(1): 91-97, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27894586

RESUMO

The size of the thoracodorsal artery perforator (TDAP) flap or pedicle, in general, may be found to be inadequate. Pre-expansion of the flap before harvest can be a solution to increase the size of the TDAP flap in such instances. The pre-expanded TDAP flap can be used to reconstruct large-sized defects with the advantage of primary closure of the donor site. This article presents details on the surgical technique and provides discussion of the authors' experiences.


Assuntos
Retalho Perfurante/irrigação sanguínea , Procedimentos de Cirurgia Plástica/métodos , Expansão de Tecido , Ferimentos e Lesões/cirurgia , Artérias , Cicatriz/cirurgia , Cabeça/cirurgia , Humanos , Pescoço/cirurgia , Retalho Perfurante/cirurgia , Parede Torácica/irrigação sanguínea , Parede Torácica/cirurgia
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