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1.
J Clin Invest ; 131(8)2021 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-33667197

RESUMO

BACKGROUNDRejection is the primary barrier to broader implementation of vascularized composite allografts (VCAs), including face and limb transplants. The immunologic pathways activated in face transplant rejection have not been fully characterized.METHODSUsing skin biopsies prospectively collected over 9 years from 7 face transplant patients, we studied rejection by gene expression profiling, histology, immunostaining, and T cell receptor sequencing.RESULTSGrade 1 rejection did not differ significantly from nonrejection, suggesting that it does not represent a pathologic state. In grade 2, there was a balanced upregulation of both proinflammatory T cell activation pathways and antiinflammatory checkpoint and immunomodulatory pathways, with a net result of no tissue injury. In grade 3, IFN-γ-driven inflammation, antigen-presenting cell activation, and infiltration of the skin by proliferative T cells bearing markers of antigen-specific activation and cytotoxicity tipped the balance toward tissue injury. Rejection of VCAs and solid organ transplants had both distinct and common features. VCA rejection was uniquely associated with upregulation of immunoregulatory genes, including SOCS1; induction of lipid antigen-presenting CD1 proteins; and infiltration by T cells predicted to recognize CD1b and CD1c.CONCLUSIONOur findings suggest that the distinct features of VCA rejection reflect the unique immunobiology of skin and that enhancing cutaneous immunoregulatory networks may be a useful strategy in combatting rejection.Trial registrationClinicalTrials.gov NCT01281267.FUNDINGAssistant Secretary of Defense and Health Affairs, through Reconstructive Transplant Research (W81XWH-17-1-0278, W81XWH-16-1-0647, W81XWH-16-1-0689, W81XWH-18-1-0784, W81XWH-1-810798); American Society of Transplantation's Transplantation and Immunology Research Network Fellowship Research Grant; Plastic Surgery Foundation Fellowship from the American Society of Plastic Surgeons; Novo Nordisk Foundation (NNF15OC0014092); Lundbeck Foundation; Aage Bangs Foundation; A.P. Moller Foundation for the Advancement of Medical Science; NIH UL1 RR025758.


Assuntos
Apresentação de Antígeno , Transplante de Face , Perfilação da Expressão Gênica , Rejeição de Enxerto/imunologia , Lipídeos/imunologia , Receptores de Antígenos de Linfócitos T , Pele/imunologia , Linfócitos T/imunologia , Feminino , Seguimentos , Rejeição de Enxerto/genética , Rejeição de Enxerto/patologia , Humanos , Masculino , Estudos Prospectivos , Receptores de Antígenos de Linfócitos T/genética , Receptores de Antígenos de Linfócitos T/imunologia , Pele/patologia
2.
Plast Reconstr Surg ; 144(4): 608e-618e, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31568296

RESUMO

BACKGROUND: A critical barrier to successful limb replantation and allotransplantation is the maximum allowable limb ischemia time of 4 to 6 hours. The current gold standard is to preserve amputated limbs on an ice slurry. Experimental machine perfusion has yielded promising results as an alternative. In particular, hypothermic acellular perfusion has enabled preservation of amputated limbs for up to 12 hours thus far. METHODS: Amputated forelimbs of Yorkshire pigs were preserved on static cold storage at 4°C for 4 hours (static cold storage group) or perfused at 8°C for 24 hours (perfusion group) with oxygenated modified STEEN Solution perfusate before replantation. Animals were followed up for 7 days after replantation. RESULTS: Eight animals underwent replantation (cold storage group, n = 4; perfusion group, n = 4). Seventy-five and 100 percent of animals in the static cold storage and perfusion groups survived for 7 days, respectively. Glycogen and adenosine triphosphate remained stable throughout perfusion. Heart and respiratory rate after replantation were increased in the static cold storage group. There was increased damage in muscle biopsy specimens obtained from animals in the static cold storage group after 7 days when compared with those from animals in the perfusion group. CONCLUSIONS: Hypothermic acellular ex vivo perfusion of limbs for up to 24 hours enables tissue preservation comparable to that obtained with conventional static cold storage for 4 hours and may reduce muscle damage and systemic reactions on limb replantation. Translation to human limbs may help improve limb replantation and allotransplantation outcomes.


Assuntos
Membro Anterior/cirurgia , Perfusão/métodos , Reimplante/métodos , Preservação de Tecido/métodos , Animais , Feminino , Distribuição Aleatória , Soluções/administração & dosagem , Suínos , Fatores de Tempo
3.
JAMA Facial Plast Surg ; 21(4): 278-285, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-30998810

RESUMO

IMPORTANCE: Acute rejection is one of the most frequent complications in facial transplantation, with potentially severe consequences for the recipient if overlooked. Clinical signs, such as erythema or edema, are helpful to diagnose acute rejection in the early follow-up stage; however, it is not well known whether these clinical signs remain reliable markers of acute rejection beyond the second posttransplant year. OBJECTIVE: To determine the diagnostic value of clinical signs of acute rejection after facial transplantation over time. DESIGN, SETTING, AND PARTICIPANTS: A retrospective, single-center cohort study was conducted of patients who underwent facial transplantation at Brigham and Women's Hospital between April 2009 and October 2014, with up to an 8-year follow-up. Medical records were reviewed until September 30, 2017. The medical records from 104 encounters with 7 patients who underwent partial or full facial transplantation were analyzed for symptoms of rejection, immunosuppressive therapy, and histopathologic findings. MAIN OUTCOMES AND MEASURES: The occurrence of 5 clinical signs of acute rejection were evaluated: erythema, edema, exanthema, suture line erythema, and mucosal lesions. Odds ratios (ORs) were calculated to determine the statistically significant association of these signs with the histopathologic diagnosis of rejection. In addition, tacrolimus blood levels, as a surrogate marker of immunosuppressive therapy, were evaluated. RESULTS: Of the 7 patients included in the study, 5 were men. The mean follow-up was 66 months (range, 35-101). Of 104 clinical encounters, 46 encounters (44.2%) represented rejection episodes and 58 encounters (55.8%) represented no-rejection episodes. Beyond 2 years posttransplantation, only erythema (OR, 6.53; 95% CI, 1.84-20.11; P = .004) and exanthema (OR, ∞; 95% CI, 2.2-∞; P = .004) were demonstrated to be reliable clinical signs of acute rejection in facial transplantation. There was also a statistically significant association of subtherapeutic tacrolimus levels with late rejection episodes (OR, 3.79; 95% CI, 1.25-12.88; P = .03). In addition, the occurrence of subclinical rejection was more frequent during later follow-up times (7 [24.1%] late rejections vs 1 [5.9%] early rejection). Five of 8 subclinical rejections (62.5%) were associated with subtherapeutic tacrolimus levels. CONCLUSIONS AND RELEVANCE: Clinical signs of acute rejection in facial transplantation appear to be of limited diagnostic value, particularly after the second postoperative year. Until alternative biomarkers for rejection are identified, protocol skin biopsies will remain necessary for guiding assessments of allograft rejection. LEVEL OF EVIDENCE: 3.


Assuntos
Transplante de Face , Rejeição de Enxerto/diagnóstico , Adulto , Biópsia , Diagnóstico Diferencial , Eritema/diagnóstico , Exantema/diagnóstico , Feminino , Seguimentos , Humanos , Imunossupressores/administração & dosagem , Masculino , Pessoa de Meia-Idade
4.
Am J Transplant ; 19(4): 1168-1177, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30312535

RESUMO

Face vascularized composite allografts (FVCAs) have helped patients with severe facial disfigurement, with acute rejection now largely controlled through iatrogenic immunosuppression. However, little is known regarding the incidence and mechanism(s) of more long-term pathologic alterations in FVCAs that may affect function and graft durability. Protocol surveillance biopsy specimens for up to an 8-year interval in 7 patients who received FVCAs at our institution revealed histopathologic evidence of chronic rejection. Clinical manifestations included features of premature aging, mottled leukoderma accentuating suture lines, telangiectasia, and dryness of nasal mucosa. Pathologic changes consisted of epidermal thinning accompanied by discrete foci of lymphocyte-mediated cytotoxicity, hyperkeratosis, follicular plugging, vascular ectasia, and sclerosis beneath the epidermal layer associated with collagen type I deposition. Genomic interrogation and immunohistochemistry of sclerotic zones revealed upregulation of the AP-1 pathway components, JunB and c-Fos, previously implicated in overproduction of type I dermal collagen in the setting of systemic sclerosis. We conclude that some patients develop chronic rejection in FVCAs with striking similarities to alterations seen in certain autoimmune cutaneous disorders (lupus erythematosus and scleroderma/chronic sclerodermoid graft-versus-host disease). Identification of relevant pathways and genes, such as JunB and c-Fos, may provide new targets for preventative therapies for chronic immune-mediated changes in vascularized composite allografts.


Assuntos
Aloenxertos Compostos/imunologia , Transplante de Face/métodos , Rejeição de Enxerto , Adulto , Doença Crônica , Feminino , Perfilação da Expressão Gênica , Humanos , Imunossupressores/uso terapêutico , Masculino , Pessoa de Meia-Idade
5.
J Surg Res ; 232: 137-145, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30463709

RESUMO

BACKGROUND: Ischemia-reperfusion injury remains the major limiting factor for limb replantation and transplantation. Static cold storage (SCS) on ice currently represents the standard mode of preservation but is limited to 6 h of duration. Ex vivo machine perfusion has evolved as a potential alternative to safely extend the duration of ex vivo preservation by providing continuous supply of oxygen and nutrients. This study aims to evaluate underlying molecular mechanisms of both preservation modalities. METHODS: We assessed molecular changes in amputated porcine forelimbs stored on ice at 4°C for 2 h (n = 2) and limbs perfused with Perfadex solution at 10°C for 2 h (n = 3) or 12 h (n = 3) before replantation. Muscle biopsies were examined for histological changes and gene expression levels using H&E staining and a hypoxia-related PCR gene array, respectively. RESULTS: Histology revealed only minor differences between the ice (SCS) and perfusion groups after 2 h of preservation, with decreased muscle fiber disruption in the perfusion groups compared with the ice (SCS) group. Perfused limbs demonstrated downregulation of genes coding for glycolytic pathways and glucose transporters after 2 h and 12 h when compared with SCS after 2 h. Similarly, genes that induce angiogenesis and those that are activated on DNA damage were downregulated in both perfusion groups as compared with SCS. CONCLUSIONS: Perfusion of porcine limbs resulted in less activation of hypoxia-related gene families when compared with SCS. This may indicate a state more closely resembling physiological conditions during perfusion and potentially limiting ischemic injury. Our study confirms ex vivo perfusion for up to 12 h as a viable alternative for preservation of vascularized composite tissues.


Assuntos
Extremidades/cirurgia , Hipóxia/metabolismo , Preservação de Órgãos , Reimplante , Animais , Temperatura Baixa , Dano ao DNA , Feminino , Glucose/metabolismo , Perfusão , Suínos , Transcriptoma , Fator A de Crescimento do Endotélio Vascular/genética
6.
Sci Rep ; 8(1): 14915, 2018 10 08.
Artigo em Inglês | MEDLINE | ID: mdl-30297859

RESUMO

Face transplantation is a viable treatment option for carefully selected patients with devastating injuries to the face. However, acute rejection episodes occur in more than 80% of recipients in the first postoperative year. Unfortunately, neither a correlation between histological grades of rejection and anti-rejection treatment nor systemic surrogate markers of rejection in face transplantation are established in clinical routine. Therefore, we utilized next generation aptamer-based SOMAscan proteomics platform for non-invasive rejection biomarker discovery. Longitudinal serum samples from face transplant recipients with long-term follow-up were included in this study. From the 1,310 proteins analyzed by SOMAscan, a 5-protein signature (MMP3, ACY1, IL1R2, SERPINA4, CPB2) was able to discriminate severe rejection from both no-rejection and nonsevere rejection samples. Technical validation on ELISA platform showed high correlation with the SOMAscan data for the MMP3 protein (rs = 0.99). Additionally, MMP3 levels were significantly increased during severe rejection as compared to no-rejection (p = 0.0009) and nonsevere rejection (p = 0.0173) episodes. Pathway analyses revealed significant activation of the metallopeptidase activity during severe face transplant rejection. This pilot study demonstrates the feasibility of SOMAscan to identify non-invasive candidate biomarkers of rejection in face transplantation. Further validation in a larger independent patient cohort is needed.


Assuntos
Transplante de Face/efeitos adversos , Rejeição de Enxerto/sangue , Metaloproteinase 3 da Matriz/sangue , Doença Aguda , Adulto , Biomarcadores/sangue , Biópsia , Análise por Conglomerados , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Regulação para Cima
7.
J Surg Oncol ; 118(5): 800-806, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30098294

RESUMO

In the past 20 years, reconstructive transplantation (RT) has emerged as a viable reconstructive option for carefully selected patients. More than 100 upper extremity and 40 face transplants have been performed worldwide to date. Concomitantly, the portfolio of reconstructive transplantation has been extended by additional procedures such as lower extremities, abdominal wall, neck, uterus, genitourinary, and pediatric transplants. In the present review article, we aim to summarize the current state of knowledge about this exciting field.


Assuntos
Transplante de Órgãos/tendências , Previsões , Rejeição de Enxerto/prevenção & controle , Sobrevivência de Enxerto , Humanos , Imunossupressores/uso terapêutico , Microcirurgia , Transplante de Órgãos/efeitos adversos
8.
J Plast Reconstr Aesthet Surg ; 71(5): 624-636, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29426809

RESUMO

BACKGROUND: Smoking is considered to be a significant risk factor for the development of postoperative complications after various surgical procedures, mainly by limiting oxygen delivery to tissues. Evidence on the collective impact of smoking in aesthetic procedure outcomes is scarce. The aim of this study is to evaluate the current evidence on the association between smoking and postoperative outcomes in patients who underwent common elective procedures in plastic surgery. METHODS: PubMed and Cochrane bibliographical databases were searched from January 1950 to October 2016 for studies reporting on patients who underwent facelift, abdominoplasty, breast reduction and breast reconstruction and for studies with included data on smoking history of treated patients. RESULTS: Fifty-three studies reporting on postoperative complications in tobacco users undergoing facelift, abdominoplasty, breast reduction and reconstruction were identified. Tobacco use is found to significantly increase the total number of postoperative complications as far as abdominoplasty (OR: 5.43; 95% CI = 2.92-10.10), breast reduction (OR: 2.36; 95% CI = 1.64-3.39) and breast reconstruction (OR: 1.91; 95% CI = 1.69-2.17) are concerned. Smoking history does not significantly affect total postoperative complications after facelift procedures (OR: 3.36; 95% CI = 0.92-12.30). CONCLUSIONS: Smoking predisposes to surgical site infections, delayed wound healing and skin necrosis in patients undergoing the most common aesthetic procedures in plastic surgery. More rigorous and detailed reporting on the history of tobacco use and surgical outcomes following plastic surgery procedures is needed to better quantify the impact of smoking on the overall postoperative care for this patient population.


Assuntos
Procedimentos Cirúrgicos Eletivos , Fumar/efeitos adversos , Cirurgia Plástica , Abdominoplastia , Humanos , Mamoplastia , Complicações Pós-Operatórias , Fatores de Risco
9.
J Craniofac Surg ; 29(4): 843-847, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29381613

RESUMO

BACKGROUND: Trismus can be a challenging consequence of ballistic trauma to the face, and has rarely been described in the setting of face transplantation. Almost half of all current face transplant recipients in the world received transplantation to restore form and function after a ballistic injury. Here we report our experience and challenges with long standing trismus after face transplantation. METHODS: We reviewed the medical records of our face transplant recipients whose indication was ballistic injury. We focused our review on trismus and assessed the pre-, peri- and postoperative planning, surgery and functional outcomes. RESULTS: Two patients received partial face transplantation, including the midface for ballistic trauma. Both patients suffered from impaired mouth opening, speech intelligibility, and oral competence. Severe scarring of the temporomandibular joint (TMJ) required intraoperative release in both patients, and additional total condylectomy on the left side 6 months posttransplant for 1 patient. Posttransplant, both patients achieved an improvement in mouth opening; however, there was persistent trismus. One year after transplantation, range of motion of the jaw had improved for both patients. Independent oral food intake was possible 1 year after surgery, although spillage of liquids and mixed consistency solids persisted. Speech intelligibility testing showed impairments in the immediate postoperative period, with improvement to over 85% for both patients at 1 year posttransplant. CONCLUSIONS: Ballistic trauma to the face and subsequent reconstructive measures can cause significant scarring and covert injuries to structures such as the TMJ, resulting in long standing trismus. Meticulous individual planning prior to interventions such as face transplantation must take these into account. We encourage intraoperative evaluation of these structures as well as peri- and postoperative treatment when necessary. Due to the nature of the primary injury, functional outcomes after face transplantation in these patients may differ substantially from those of other indications.


Assuntos
Transplante de Face/efeitos adversos , Procedimentos de Cirurgia Plástica , Complicações Pós-Operatórias , Trismo , Adulto , Face/fisiopatologia , Face/cirurgia , Humanos , Masculino , Complicações Pós-Operatórias/fisiopatologia , Complicações Pós-Operatórias/cirurgia , Amplitude de Movimento Articular , Trismo/etiologia , Trismo/fisiopatologia , Trismo/cirurgia , Ferimentos por Arma de Fogo
11.
Innov Surg Sci ; 2(4): 171-187, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31579751

RESUMO

Pathophysiological changes that occur during ischemia and subsequent reperfusion cause damage to tissues procured for transplantation and also affect long-term allograft function and survival. The proper preservation of organs before transplantation is a must to limit these injuries as much as possible. For decades, static cold storage has been the gold standard for organ preservation, with mechanical perfusion developing as a promising alternative only recently. The current literature points to the need of developing dedicated preservation protocols for every organ, which in combination with other interventions such as ischemic preconditioning and therapeutic additives offer the possibility of improving organ preservation and extending it to multiple times its current duration. This review strives to present an overview of the current body of knowledge with regard to the preservation of organs and tissues destined for transplantation.

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