Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 725
Filtrar
1.
Int J Mol Sci ; 23(14)2022 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-35887286

RESUMO

Introduction: Three-dimensional bioprinting can be considered as an advancement of the classical tissue engineering concept. For bioprinting, cells have to be dispersed in hydrogels. Recently, a novel semi-synthetic thiolene hydrogel system based on norbornene-functionalized gelatin (GelNB) and thiolated gelatin (GelS) was described that resulted in the photoclick hydrogel GelNB/GelS. In this study, we evaluated the printability and biocompatibility of this hydrogel system towards adipose-tissue-derived mesenchymal stem cells (ASCs). Methods: GelNB/GelS was synthesized with three different crosslinking densities (low, medium and high), resulting in different mechanical properties with moduli of elasticity between 206 Pa and 1383 Pa. These hydrogels were tested for their biocompatibility towards ASCs in terms of their viability, proliferation and differentiation. The extrusion-based bioprinting of ASCs in GelNB/GelS-high was performed to manufacture three-dimensional cubic constructs. Results: All three hydrogels supported the viability, proliferation and chondrogenic differentiation of ASCs to a similar extent. The adipogenic differentiation of ASCs was better supported by the softer hydrogel (GelNB/GelS-low), whereas the osteogenic differentiation was more pronounced in the harder hydrogel (GelNB/GelS-high), indicating that the differentiation fate of ASCs can be influenced via the adaption of the mechanical properties of the GelNB/GelS system. After the ex vivo chondrogenic differentiation and subcutaneous implantation of the bioprinted construct into immunocompromised mice, the production of negatively charged sulfated proteoglycans could be observed with only minimal inflammatory signs in the implanted material. Conclusions: Our results indicate that the GelNB/GelS hydrogels are very well suited for the bioprinting of ASCs and may represent attractive hydrogels for subsequent in vivo tissue engineering applications.


Assuntos
Bioimpressão , Células-Tronco Mesenquimais , Animais , Bioimpressão/métodos , Gelatina , Hidrogéis , Camundongos , Norbornanos , Osteogênese , Impressão Tridimensional , Compostos de Sulfidrila , Engenharia Tecidual/métodos , Alicerces Teciduais
2.
Sci Rep ; 12(1): 1886, 2022 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-35115589

RESUMO

The biopsy technique of choice in soft tissue sarcoma (STS) diagnosis is controversial. We examined the diagnostic accuracy of percutaneous core needle biopsy (CNB) and compared it to open incisional biopsy. A retrospective study included 91 incisional biopsies and 102 CNBs. A pair-match investigation was conducted on 19 patient pairs, comparing sensitivity, specificity, and diagnostic accuracy. Furthermore, we investigated the role of molecular pathology in sarcoma diagnostics. In 81/91 (89%) patients with incisional biopsy, the entity was confirmed by definitive pathology, whereas this was the case in 89/102 (87%) CNB patients (p = 0.52). Grading remained unchanged in 46/55 (84%) of incisional and 54/62 (87%) of CNBs (p = 0.61). The pair matched analysis showed that the correct entity was determined in 96% of incisional and 97.6% of core needle biopsies. The time between the initial consultation and the interdisciplinary tumor board's treatment recommendation was shorter in core needle biopsies (8.37 vs. 15.63 days; p < 0.002). Incisional biopsies led to two wound infections and one hematoma, whereas wound infection occurred in one patient after CNB. CNB leads to faster diagnosis while reaching the same histological accuracy and is less burdensome for patients. Still, surgeons need to remain aware of the possibility of biopsy failure.


Assuntos
Sarcoma/patologia , Neoplasias de Tecidos Moles/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia com Agulha de Grande Calibre , Bases de Dados Factuais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Estudos Retrospectivos
3.
J Reconstr Microsurg ; 38(2): 151-159, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34404104

RESUMO

BACKGROUND: Distal lower extremity reconstruction can be challenging in terms of flap design. Bulky flaps result in limited mobility accompanied with the need of customized footwear. Raising the ALT-flap in a superficial fascial plane (thin ALT-flap) can be beneficial. This study evaluates thin ALT-flaps for lower distal extremity reconstruction. METHODS: In a retrospective study, patients that underwent microvascular extremity reconstruction at the level of the ankle and dorsal foot at the University of Freiburg from 2008-2018 were reviewed. RESULTS: 95 patients could be included in the study (35 perforator flaps, 8 fascia flaps and 54 muscle flaps).Among the perforator flaps, 21 ALT-flaps were elevated conventionally and 14 in the superficial fascial plane (thin ALT-flap). Among the conventional ALT-flaps, there was one flap loss (5%) and one successful revision (5%). 5(24%) flaps received secondary thinning. 57%(n = 12) were able to wear conventional footwear. There were 2(15%) successful revisions of thin ALT-flaps. 100% of thin ALT-flaps survived and 85%(n = 11) of the patients wore ordinary footwear after defect coverage.Among fascial flaps, 50%(n = 4) had to be revised with 2(25%) complete and 1 (13%) partial flap loss. All patients achieved mobility in ordinary shoes (n = 8).In muscle flaps, there were 7(13%) revisions and 5(9%) flap losses. 5(9%) flaps received secondary thinning. Only 33%(n = 18) were mobile in ordinary footwear. CONCLUSION: The thin ALT-flap is a save one-stage evolution for lower distal extremity reconstruction with a favorable flap survival rate. Compared with conventional ALT-flaps it might be beneficial in reducing the need for expensive custom fitted shoes and secondary thinning procedures.


Assuntos
Retalho Perfurante , Procedimentos de Cirurgia Plástica , Tornozelo/cirurgia , Humanos , Estudos Retrospectivos , Resultado do Tratamento
4.
Ann Plast Surg ; 87(5): 556-561, 2021 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-34699434

RESUMO

BACKGROUND: This study investigates the relationship between Edmonton Obesity Staging System (EOSS) and the occurrence of postoperative complications after abdominoplasty in massive weight loss patients. METHODS: A single-institution retrospective review of patients undergoing abdominoplasty between 2009 and 2019 after massive weight loss. Demographic data, laboratory findings, known risk factors for postoperative complications, as well as data on major and minor complications were extracted from the patient charts. Logistic regression models were used to investigate the relationship between the variables. RESULTS: Four hundred and five patients were included in the study. The prevalence of EOSS stages was: 0 (no comorbidities, N = 151, 37%), 1 (mild conditions, N = 40, 10%), 2 (moderate conditions, N = 149, 36%) and 3 (severe conditions, N = 70, 17%). Regression analysis showed that, controlling for body mass index (BMI), BMI Δ (maximal BMI - BMI at presentation), bariatric surgery, volume of resected tissue, and duration of surgery, EOSS stage significantly associated with the occurrence of postoperative complications. Compared with EOSS stage 0, EOSS stages 2 and 3 patients were associated with significantly more minor and major complications, respectively. The volume of resected tissue, BMI Δ, and age were associated with the occurrence of major complications. A regression model of comorbidities comprising the EOSS revealed a significant association of variables diabetes mellitus and hypertension with the occurrence of postoperative complications. CONCLUSIONS: Edmonton Obesity Staging System is a robust predictor of postoperative complications in abdominoplasty.


Assuntos
Abdominoplastia , Cirurgia Bariátrica , Obesidade Mórbida , Abdominoplastia/efeitos adversos , Cirurgia Bariátrica/efeitos adversos , Índice de Massa Corporal , Humanos , Obesidade/epidemiologia , Obesidade/cirurgia , Obesidade Mórbida/cirurgia , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Estudos Retrospectivos
5.
J Oncol ; 2021: 5580431, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34007275

RESUMO

There is no consensus regarding follow-up after soft tissue sarcoma (STS) treatment. This study examines the efficacy and the cost-benefit of MRI imaging for discovering recurrence. A retrospective analysis was performed, collecting data on patient demography, tumor characteristics, treatment, and follow-up. Imaging was correlated to the clinical course, and sensitivity, specificity, and predictive values were calculated. The number needed to screen and costs of finding recurrence are reported. Amongst 216 sarcomas, 73 (35%) exhibited local recurrence during a follow-up of 5.3 ± 3.5 years. 173 entities had complete MRI follow-up with 58 (34%) local recurrences. Thirty-three (57%) were discovered by MRI, 8 (14%) by clinical presentation, and 17 (29%) simultaneously. There was a sensitivity of 100.00%, a specificity of 89%, a positive predictive value of 32%, and a negative predictive value of 100% for detecting local recurrence with MRI. Our data confirm the modalities and intervals proposed by the German guidelines for sarcoma care. The recommended MRI intervals should not be extended. MRI is more cost-effective than clinical examination; still, both modalities should be performed together to discover the maximum number of recurrences.

6.
J Plast Reconstr Aesthet Surg ; 74(11): 3120-3127, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34045144

RESUMO

BACKGROUND: This study investigates the correlation between the Edmonton Obesity Staging System (EOSS) and the occurrence of postoperative complications after medial thigh lift in formerly obese patients. PATIENTS AND METHODS: A single-institution retrospective review of patients undergoing medial thigh lift between 2009 and 2019 after massive weight loss. Data on demography, comorbidities, surgery, and postoperative outcome were extracted from patients' charts. Patients were grouped into EOSS categories. Complications were classified into minor and major. Logistic regression analysis was performed to determine the association between risk factors and complications. RESULTS: One hundred and eight patients were included in the study. Complications occurred in 76 (70%) of the patients, most of which were minor (60/108, 56%). Complications increased with increasing EOSS stage, and all EOSS 3 patients had complications. Classification as EOSS 2 or 3 significantly associated with occurrence of postoperative complications (OR 99.3, p<0.001) as well as minor and major complications individually (OR 3.1 and 6.5, p<0.05). This effect was independent of body mass index (BMI), maximum BMI loss, type of weight loss, volume of liposuction, weight of resected tissue, and type of surgery. CONCLUSION: EOSS is a robust and independent predictor for postoperative complications in medial thigh lift surgery after massive weight loss.


Assuntos
Obesidade/complicações , Complicações Pós-Operatórias/etiologia , Coxa da Perna/cirurgia , Redução de Peso , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Retrospectivos , Fatores de Risco
7.
PLoS One ; 16(3): e0238330, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33661950

RESUMO

The homogeneity of the genetically modified single-cells is a necessity for many applications such as cell line development, gene therapy, and tissue engineering and in particular for regenerative medical applications. The lack of tools to effectively isolate and characterize CRISPR/Cas9 engineered cells is considered as a significant bottleneck in these applications. Especially the incompatibility of protein detection technologies to confirm protein expression changes without a preconditional large-scale clonal expansion creates a gridlock in many applications. To ameliorate the characterization of engineered cells, we propose an improved workflow, including single-cell printing/isolation technology based on fluorescent properties with high yield, a genomic edit screen (Surveyor assay), mRNA RT-PCR assessing altered gene expression, and a versatile protein detection tool called emulsion-coupling to deliver a high-content, unified single-cell workflow. The workflow was exemplified by engineering and functionally validating RANKL knockout immortalized mesenchymal stem cells showing bone formation capacity of these cells. The resulting workflow is economical, without the requirement of large-scale clonal expansions of the cells with overall cloning efficiency above 30% of CRISPR/Cas9 edited cells. Nevertheless, as the single-cell clones are comprehensively characterized at an early, highly parallel phase of the development of cells including DNA, RNA, and protein levels, the workflow delivers a higher number of successfully edited cells for further characterization, lowering the chance of late failures in the development process.


Assuntos
Bioimpressão/métodos , Clonagem Molecular/métodos , Técnicas de Inativação de Genes/métodos , Células-Tronco Mesenquimais/metabolismo , Ligante RANK/genética , Análise de Célula Única/métodos , Sistemas CRISPR-Cas , Diferenciação Celular , Linhagem Celular , Humanos , Células-Tronco Mesenquimais/citologia , Osteoblastos/citologia , Osteoblastos/metabolismo , Fluxo de Trabalho
8.
BMC Surg ; 21(1): 100, 2021 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-33622311

RESUMO

BACKGROUND: Epidermolysis bullosa is a group of rare inherited skin diseases characterized by blister formation following mechanical skin trauma. Epidermolysis bullosa is associated with increased skin cancer rates, predominantly squamous cell carcinomas, yet to our best knowledge, there is no reported case of dermatofibrosarcoma protuberans in a patient with Epidermolysis bullosa. CASE PRESENTATION: Here, we present a 26-year-old man with junctional epidermolysis bullosa, who developed a DFSP on the neck. Initial, the skin alteration was mistakenly not considered malignant, which resulted in inadequate safety margins. The complete resection required a local flap to close the defect, which is not unproblematic because of the chronic inflammation and impaired healing potential of the skin due to Epidermolysis bullosa. CONCLUSIONS: To our best knowledge, this is the first reported case of a skin-associated sarcoma in a patient with EB; however, further investigation is required to verify a correlation.


Assuntos
Dermatofibrossarcoma , Epidermólise Bolhosa Juncional , Neoplasias Cutâneas , Adulto , Dermatofibrossarcoma/diagnóstico , Dermatofibrossarcoma/cirurgia , Epidermólise Bolhosa Juncional/epidemiologia , Humanos , Masculino , Neoplasias Cutâneas/diagnóstico , Neoplasias Cutâneas/cirurgia
9.
Biol Chem ; 402(6): 693-702, 2021 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-33544464

RESUMO

Mesenchymal stem cells (MSCs) play an important role in tissue engineering applications aiming at the regeneration or substitution of damaged tissues. In this context, off-the-shelf allogeneic MSCs would represent an attractive universal cell source. However, immune rejection is a major limitation for the clinical use of allogeneic MSCs. Immune rejection is mediated by the expression of major histocompatibility complexes (MHC)-I and -II on the donor cells. In this study, we eliminated MHC-I and/or MHC-II expression in human MSCs by using the CRISPR/Cas9 technology and investigated the effect of the individual or combined knockout of MHC-I and MHC-II on MSC survival after transplantation into immunocompetent mice. Elimination of MHC-I and/or MHC-II expression did not affect mesenchymal marker gene expression, viability, proliferation and the differentiation potential of MSCs in vitro. However, cell survival of transplanted MSCs was significantly elevated in MHC-I and MHC-II deficient MSCs. A direct side-by-side comparison does not reveal any significant difference in the immunogenicity of MHC-I and MHC-II knockout MSCs. Moreover, double knockout of MHC-I and MHC-II did not further increase in vivo cell survival of transplanted MSCs. Our results demonstrate that knockout of MHC-I and/or MHC-II represents an effective strategy to prevent immune rejection of allogeneic MSCs.


Assuntos
Complexo Principal de Histocompatibilidade/imunologia , Células-Tronco Mesenquimais/imunologia , Sistemas CRISPR-Cas/genética , Sistemas CRISPR-Cas/imunologia , Proliferação de Células , Sobrevivência Celular , Células Cultivadas , Citometria de Fluxo , Edição de Genes , Humanos , Complexo Principal de Histocompatibilidade/genética , Células-Tronco Mesenquimais/citologia
10.
Handchir Mikrochir Plast Chir ; 53(2): 110-118, 2021 Apr.
Artigo em Alemão | MEDLINE | ID: mdl-32977347

RESUMO

BACKGROUND: Since 2015/16 the DGPRÄC collects, evaluates and publishes the research activities of academic sections, departments and clinics for plastic surgery at university hospitals in Germany, in order to raise the awareness of plastic surgical research performance. MATERIALS AND METHODS: The directors of plastic surgical academic institutions were contacted via the DGPRÄC and asked to report any requested/approved and rejected research applications to public, non-public and industrial funding organizations. Data was collected in our previously established online database: https://docs.google.com/forms/d/e/1FAIpQLSe6F5xmTyw-k7VKJx_2jkPA4LBXsA0sgBGMrC3rx_4bHj6uzQ/viewform?usp=sf_link. In addition, applications were identified via the DFG's public database GEPRIS. RESULTS: A total of 41 funding applications to the public funding institutes DFG, BMBF, BMWi, BMG and EU were identified. 75.6 % (31/41) of the applications had already been approved at the time of data collection, of which 77.4 % (24/31) were DFG, 9.7 % (3/31) were BMWi, 6.5 % (2/31) were EU and 3.2 % (1/31) were BMBF or BMG applications. The average funding amounted to 358 301 Euro. In 50.0 % (12/24) of the cases, the approved DFG proposals were assigned to the subject review board 205-27 Orthopedics, Trauma Surgery, Reconstructive Surgery. CONCLUSION: The continuous publication of plastic surgical research funding reports submitted by the convention of university plastic surgeons of the DGPRÄC portraits the excellent, collaborative research activity in the field of plastic surgery.


Assuntos
Procedimentos de Cirurgia Plástica , Cirurgiões , Cirurgia Plástica , Estética , Alemanha , Humanos , Sistema de Registros
11.
PLoS One ; 15(11): e0233586, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33232326

RESUMO

BACKGROUND: Three-dimensional (3D) scanning is an established method of breast volume estimation. However, this method can never be entirely precise, since the thoracic wall cannot be imaged by the surface scanner. Current methods rely on interpolation of the posterior breast border from the surrounding thoracic wall. Here, we present a novel method to calculate the posterior border and increase the accuracy of the measurement. METHODS: Using principal component analysis, computed tomography images were used to build a statistical shape model (SSM) of the thoracic wall. The model was fitted to 3D images and the missing thoracic wall curvature interpolated (indirect volumetry). The calculations were evaluated by ordinary least squares regression between the preoperative and postoperative volume differences and the resection weights in breast reduction surgery (N = 36). Also, an SSM of the breast was developed, allowing direct volumetry. Magnetic-resonance images (MRI) and 3D scans were acquired from 5 patients in order to validate the direct 3D volumetry. RESULTS: Volumetry based on a SSM exhibited a higher determination coefficient (R2 = 0,737) than the interpolation method (R2 = 0,404). The methods were not equivalent (p = 0.75), suggesting that the methods significantly differ. There was no influence of BMI on the correlation in either method. The MRI volumetry had a strong correlation with the 3D volumetry (R2 = 0,978). CONCLUSION: The SSM-based method of posterior breast border calculation is reliable and superior to the currently used method of interpolation. It should serve as a basis of software applications aiming at calculation of breast volume from 3D surface scanning data.


Assuntos
Mama/diagnóstico por imagem , Mama/cirurgia , Imageamento Tridimensional/métodos , Adulto , Procedimentos Cirúrgicos de Citorredução , Feminino , Humanos , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Modelos Estatísticos , Análise de Componente Principal
12.
Biotechnol Bioeng ; 117(12): 3902-3911, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32749669

RESUMO

Bioprinting can be considered as a progression of the classical tissue engineering approach, in which cells are randomly seeded into scaffolds. Bioprinting offers the advantage that cells can be placed with high spatial fidelity within three-dimensional tissue constructs. A decisive factor to be addressed for bioprinting approaches of artificial tissues is that almost all tissues of the human body depend on a functioning vascular system for the supply of oxygen and nutrients. In this study, we have generated cuboid prevascularized bone tissue constructs by bioprinting human adipose-derived mesenchymal stem cells (ASCs) and human umbilical vein endothelial cells (HUVECs) by extrusion-based bioprinting and drop-on-demand (DoD) bioprinting, respectively. The computer-generated print design could be verified in vitro after printing. After subcutaneous implantation of bioprinted constructs in immunodeficient mice, blood vessel formation with human microvessels of different calibers could be detected arising from bioprinted HUVECs and stabilization of human blood vessels by mouse pericytes was observed. In addition, bioprinted ASCs were able to synthesize a calcified bone matrix as an indicator of ectopic bone formation. These results indicate that the combined bioprinting of ASCs and HUVECs represents a promising strategy to produce prevascularized artificial bone tissue for prospective applications in the treatment of critical-sized bone defects.


Assuntos
Bioimpressão , Transplante Ósseo , Osso e Ossos , Células-Tronco Mesenquimais , Neovascularização Fisiológica , Engenharia Tecidual , Animais , Osso e Ossos/irrigação sanguínea , Osso e Ossos/metabolismo , Xenoenxertos , Células Endoteliais da Veia Umbilical Humana , Humanos , Camundongos , Camundongos SCID , Impressão Tridimensional , Alicerces Teciduais
13.
Front Oncol ; 10: 668, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32435617

RESUMO

Introduction: Resection of anorectal malignancies may result in extensive perineal/pelvic defects that require an interdisciplinary surgical approach involving reconstructive surgery. The myocutaneous gracilis flap (MGF) and the gluteal fold flap (GFF) are common options for defect coverage in this area. Here we report our experience with the MGF/GFF and compare the outcome regarding clinical key parameters. Methods: In a retrospective chart review, we collected data from the Department of Plastic Surgery of the University of Freiburg from December 2008-18 focusing on epidemiological, oncological, and therapy-related data including comorbidities (ASA Classification) and peri-/postoperative complications (Clavien-Dindo-System). Results: Twenty-nine patients were included with a mean follow-up of 17 months. Of the cases, 19 (65.5%) presented with recurrent disease, 21 (72.4%) received radiochemotherapy preoperatively, 2 (6.9%) received chemotherapy alone. Microscopic tumor free margins were achieved in 25 cases (86.2%). 17 patients (7 men, 10 women, rectal adenocarcinoma n = 11; anal squamous cell carcinoma n = 6; mean age 58.5 ± 10.68, mean BMI 23.1, mean ASA score 2.8) received a MGF (unilateral n = 10; bilateral n = 7). Twelve patients (7 men, 5 women, rectal adenocarcinoma n = 7; anal squamous cell carcinoma n = 4, proctodeal gland carcinoma n = 1, mean age 66.2 ± 9.2, mean BMI 23.6, mean ASA score 2.6) received coverage with a GFF (unilateral n = 4; bilateral n = 8). Mean operation time of coverage was 105 ± 9 min for unilateral and 163 ± 11 for bilateral MGFs, 70 ± 13 min for unilateral and 107 ± 14 for bilateral GFFs. Complications affected 62%. There was no significant difference in the complication rate between the MGF- and GFF-group. Complications were mainly wound healing disorders that did not extend the hospital stay. No flap loss and no complication that lead to long-lasting disability was documented (both groups). Pain-free sitting took more time in the GFF-group due to the location of the donor site. Conclusion: MG-flaps and GF-flaps prove to be reliable and robust techniques for perineal/pelvic reconstruction. Though flap elevation is significantly faster for GF-flaps, preoperative planning and intraoperative Doppler confirmation are advisable. With comparable complication rates, we suggest a decision-making based on distribution of adipose tissue for dead space obliteration, intraoperative patient positioning, and perforator vessel quality/distribution.

14.
Front Oncol ; 9: 1300, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31850204

RESUMO

Background: Sarcomas are tumors of mesenchymal origin with high variation in anatomical localization. Sarcomas affecting the bone often require an interdisciplinary resection and reconstruction approach. However, it is critical that microsurgical reconstruction strategies do not negatively impact tumor safety and overall survival, as limb salvage is only the secondary goal of tumor surgery. Here, we analyzed the efficacy and safety of microsurgery in interdisciplinary treatment of sarcoma affecting the bone. Patients and Methods: We performed a retrospective chart review of all patients treated for soft-tissue and bone sarcoma at the senior author's institution with a focus on bone affection and microsurgical reconstruction between 2000 and 2019. This particular subgroup was further investigated for tumor resection status, 5-year survival rate, length of hospital stay, as well as overall complication and amputation rates. Results: Between 2000 and 2019, 803 patients were operated for sarcoma resection and reconstruction by the Department of Plastic and Hand Surgery. Of these, 212 patients presented with sarcoma of the extremity affecting the bone. Within this subgroup, 40 patients required microsurgical reconstruction for limb salvage, which was possible in 38 cases. R0 resection was achieved in 93.8%. The 5-year survival was 96.7%, and the overall complication rate was 25%, of which 40% were microsurgery associated complications. Conclusion: Safe and function-preserving treatment of soft-tissue and bone sarcoma is challenging. Primary reconstruction with microsurgical techniques of sarcoma-related defects enables limb-sparing and adequate oncosurgical cancer treatment without increasing the risk for local recurrence or prolonged hospital stay. The treatment of sarcoma patients should be reserved to high-volume centers with experienced plastic surgeon embedded in a comprehensive treatment concept.

15.
J Craniomaxillofac Surg ; 47(12): 1973-1979, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31810844

RESUMO

The Cook-Swartz-Doppler probe is an easy to handle and reliable tool for free flap monitoring. In the head and neck region different confounders can affect the read out. We therefore analyzed the use of the Doppler probe regarding these potential difficulties and to compare the diagnostic accuracy in arterial or venous monitoring of free flaps in the head and neck region. A retrospective study was performed in which all patients were included who underwent free flap surgery in the head and neck region in the Department of Plastic Surgery and the Department of Maxillofacial Surgery of our institution between 2010 and 2018 and were monitored with an implanted Doppler probe. 147 free tissue transfers were included. No significance was found for arterial and venous placement of the Doppler probe for sensitivity (artery 83.3%; vein 84.6%; p = 0.87), specificity (artery 89.2%; vein 96.1%; p = 0.17) and negative predictive value (artery 96.7%; vein 94.2%; p = 0.55). A better positive predictive value for placing the Doppler probe around the artery (82.7%) than the vein (61.1%) was found in our study (p = 0.056). The better positive predictive value in arterial monitoring suggests that this is the more reliable measuring method to assess flap perfusion in the head and neck region.


Assuntos
Carcinoma de Células Escamosas/cirurgia , Retalhos de Tecido Biológico , Neoplasias de Cabeça e Pescoço/cirurgia , Monitorização Ambulatorial/métodos , Procedimentos de Cirurgia Plástica/métodos , Retalhos Cirúrgicos/irrigação sanguínea , Adulto , Idoso , Idoso de 80 Anos ou mais , Retalhos de Tecido Biológico/irrigação sanguínea , Retalhos de Tecido Biológico/fisiologia , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Fluxometria por Laser-Doppler/instrumentação , Microcirurgia/métodos , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/cirurgia , Estudos Retrospectivos
16.
J Tissue Eng Regen Med ; 13(10): 1883-1895, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31314936

RESUMO

Active nutrient supply and waste product removal are key requirements for the fabrication of long-term viable and functional tissue constructs of considerable size. This work aims to contribute to the fabrication of artificial perfusable networks with a bioprinting process, based on drop-on-demand (DoD) printing of primary endothelial cell (EC) suspension bioink (25 × 106 ± 3 × 106 cells/ml). The process results in prescribed lumen between two hydrogel layers, allowing its integration in common layering based bioprinting processes. Low volume bioink droplets (appr. 10 nl) as building blocks were deposited between two fibrin or Collagen I layers to realize shapeable, cell-rich aggregates. Unattainable with manual positioning, DoD printing allowed precise fabrication of various designs, such as spheroidal-, line-shaped, and Y-branch cellular structures, with a mean lateral extension of 285 ± 81 µm. For basic characterization, the cell suspension building blocks were systematically compared with preformed spheroids of the same cell type, passage, and number. Post printing investigations of initially loose cell arrangements showed self-assembly and formation of central lumen with a mean cross-sectional area of Ølumen = 6,400 µm2 at Day 3, lined by a single layer of CD31 positive ECs, as evaluated by confocal microscopy. Originating from this main lumen smaller, undirected side branches (Øbranches = 740 µm2 ) were formed by sprouting cells, inducing a first step towards a simplistic hierarchically organized network. These lumen could prospectively help for tissue construct perfusion in vitro or, potentially, as niche for angiogenesis of host vascularization in implants.


Assuntos
Bioimpressão/métodos , Células Endoteliais da Veia Umbilical Humana/citologia , Alicerces Teciduais/química , Adulto , Agregação Celular , Contagem de Células , Humanos , Tinta , Regeneração , Medicina Regenerativa , Esferoides Celulares/citologia
17.
J Plast Reconstr Aesthet Surg ; 72(6): 1012-1019, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30819648

RESUMO

BACKGROUND: Rejuvenation procedures of the periorbital region and the forehead, with the eyebrow as a key structure, are often performed in plastic surgery. There is no common consent on the changes of aging in this region and the consecutive treatment options. This study was designed to support the body of literature with a broader data basis about the natural changes of eyebrow position and its shape. METHODS: The brow shape, the lid axis, and the distance between both medial canthi (DMC) were analyzed retrospectively on randomly selected standardized photographs of healthy Caucasian females and males. Six defined heights of the upper brow border, including the position and height of the highest brow point (HBP) and the angle of the upper brow line, were measured. RESULTS: A total of 244 Caucasian females and males in two groups (<34 years and >55 years) were analyzed. The data showed a difference between brow shapes of young females and males, especially relating to the HBP, which is located medially in young females. The brow shape of females assimilates toward a male shape with aging. The eyebrow moves upward, the DMC widens, and the lid axis drops laterally in both sexes with aging. CONCLUSIONS: Our data suggest that rejuvenation procedures should focus on not only lifting the brow but also reshaping and stabilizing the brow, especially the HBP, which plays an important role in defining the upper brow line. Our findings can explain why lifting the brow can create not only an undesired surprise but also an older look.


Assuntos
Envelhecimento/patologia , Antropometria/métodos , Sobrancelhas/diagnóstico por imagem , Testa , Fotografação , Procedimentos de Cirurgia Plástica , Rejuvenescimento , Adulto , Feminino , Testa/patologia , Testa/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Procedimentos de Cirurgia Plástica/métodos , Procedimentos de Cirurgia Plástica/normas , Envelhecimento da Pele/patologia , População Branca
18.
Int J Cancer ; 145(4): 1148-1161, 2019 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-30779112

RESUMO

Soft tissue sarcomas (STS) are rare tumors of mesenchymal origin. About 50% of patients with STS experience relapse and more than 30% will die within 10 years after diagnosis. In this study we investigated circulating free DNA (cfDNA) and tumor-specific genetic alterations therein (circulating tumor DNA, ctDNA) as diagnostic biomarkers. Plasma concentrations and fragmentation of cfDNA was analyzed with quantitative PCR. Patients with STS (n = 64) had significantly higher plasma concentrations and increased fragmentation of cfDNA when compared to patients in complete remission (n = 19) and healthy controls (n = 41) (p < 0.01 and p < 0.001). Due to overlapping values between patients with STS and controls, the sensitivity and specificity of these assays is limited. Sensitive assays to detect genomic alterations in cfDNA of synovial sarcomas (t(X;18)), myxoid liposarcomas (t(12;16) and TERT C228T promoter mutation) and well-differentiated/de-differentiated liposarcomas (MDM2 amplifications) were established. ctDNA was quantified in nine liposarcoma patients during the course of their treatment. Levels of breakpoint t(12;16) and TERT C228T ctDNA correlated with the clinical course and tumor burden in patients with myxoid liposarcomas (n = 4). ctDNA could detect minimal residual disease and tumor recurrence. In contrast, detection of MDM2 amplifications was not sensitive enough to detect tumors in patients with well-differentiated/de-differentiated liposarcomas (n = 5). Genotyping of cfDNA for tumor specific genetic alterations is a feasible and promising approach for monitoring tumor activity in patients with myxoid liposarcomas. Detection of ctDNA during follow-up examinations despite negative standard imaging studies might warrant more sensitive imaging (e.g. PET-CT) or closer follow-up intervals to timely localize and treat recurrences.


Assuntos
DNA Tumoral Circulante/genética , Lipossarcoma Mixoide/genética , Biomarcadores Tumorais/genética , Estudos de Casos e Controles , Linhagem Celular Tumoral , Ácidos Nucleicos Livres/genética , Feminino , Genótipo , Humanos , Masculino , Mutação/genética , Recidiva Local de Neoplasia/genética , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Neoplasias de Tecidos Moles/genética
19.
Int J Colorectal Dis ; 34(3): 501-511, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30610436

RESUMO

AIM: Perineal defects following the resection of anorectal malignancies are a reconstructive challenge. Flaps based on the rectus abdominis muscle have several drawbacks. Regional perforator flaps may be a suitable alternative. We present our experience of using the gluteal fold flap (GFF) for reconstructing perineal and pelvic defects. METHODS: We used a retrospective chart review and follow-up examinations focusing on epidemiological, oncological (procedure and outcome), and therapy-related data. This included postoperative complications and their management, length of hospital stay, and time to heal. RESULTS: Twenty-two GFFs (unilateral n = 8; bilateral n = 7) were performed in 15 patients (nine women and six men; anal squamous cell carcinoma n = 8; rectal adenocarcinoma n = 7; mean age 65.5 + 8.2 years) with a mean follow-up time of 1 year. Of the cases, 73.3% were a recurrent disease. Microscopic tumor resection was achieved in all but one case (93.3%). Seven cases had no complications (46.7%). Surgical complications were classified according to the Clavien-Dindo system (grades I n = 2; II n = 2; IIIb n = 4). These were mainly wound healing disorders that did not affect mobilization or discharge. The time to discharge was 22 + 9.9 days. The oncological outcomes were as follows: 53.3% of the patients had no evidence of disease, 20% had metastatic disease, 20% had local recurrent disease, and one patient (6.7%) died of other causes. CONCLUSIONS: The GFF is a robust, reliable flap suitable for perineal and pelvic reconstruction. It can be raised quickly and easily, has an acceptable complication rate and donor site morbidity, and does not affect the abdominal wall.


Assuntos
Tecido Adiposo/cirurgia , Nádegas/cirurgia , Fáscia/patologia , Retalho Perfurante/patologia , Períneo/cirurgia , Procedimentos de Cirurgia Plástica/métodos , Pele/patologia , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Cuidados Pós-Operatórios
20.
J Plast Reconstr Aesthet Surg ; 72(3): 505-512, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30509736

RESUMO

BACKGROUND: Synchronicity of the oral commissure movement of a bilateral smile is a significant goal for reconstruction in facial reanimation and may only be guaranteed with use of the facial nerve as a donor nerve. Yet over the years several studies report some degree of spontaneity in certain patients when using a non-facial donor nerve, which indicates that synchronous initiation of the smile might be achievable with other donor nerves. We designed a prospective cohort study to evaluate whether pre-operative involuntary activation of the masseteric nerve during smile predicts development of a synchronous smile development when using the masseteric nerve for reanimation. METHODS: In a prospective cohort study unilateral long-standing facial palsy patients scheduled for dynamic smile reanimation with a free functional muscle transplant using the masseteric nerve as a donor nerve were preoperatively evaluated via EMG for involuntary activation of the masseter muscle upon smiling, which we called coactivation. Postoperatively, six months after noting the first muscle contraction smile synchronicity was evaluated. We analyzed the synchronicity of the bilateral smile development by analyzing slow-motion video sequences of the patients that were taken while the patients were watching funny video sequences. Results were then correlated with the pre-operative EMG. RESULTS: 30 patients were recruited for this prospective study and underwent facial reanimation surgery with a free gracilis transfer innervated by the masseteric nerve. 19 patients demonstrated involuntary coactivation of the masseter muscle upon smiling and 11 did not. Postoperatively all patients could demonstrate a voluntary smile. 94% of patients who had preoperative coactivation showed a synchronous movement of the oral commissure when smiling. In those patients, that did not show activation of the masseter muscle upon smiling 0% showed synchronicity. The preoperative coactivation of the masseter muscle is able to predict the outcome regarding synchronicity of the smile with a sensitivity of 99.7%, a specificity of 88.5% and 92.5% positive predictive value and 99.6% negative predictive value (p < 0.001 for all). CONCLUSIONS: The lack of masseter co-activation with smile predicts a lack of spontaneous involuntary smile after dynamic smile reconstruction using the masseteric nerve.


Assuntos
Eletromiografia/métodos , Paralisia Facial/cirurgia , Músculo Masseter/cirurgia , Procedimentos de Cirurgia Plástica/métodos , Sorriso , Adolescente , Adulto , Expressão Facial , Feminino , Humanos , Masculino , Músculo Masseter/inervação , Microcirurgia/métodos , Projetos Piloto , Estudos Prospectivos , Adulto Jovem
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA