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INTRODUCTION: The iatrogenic effects of repairing peripheral nerve injuries (PNIs) with autografts (AGTs) encouraged the present study to involve a new approach consisting of grafting xenogeneic prerecellularized allogeneic cells instead of AGTs. METHODS: We compared sheep's AGT regenerative and functional capacity with decellularized human nerves prerecellularized with allogeneic Schwann-like cell xenografts (onwards called xenografts). Mesenchymal stem cells were isolated from ovine adipose tissue and induced in vitro to differentiate into Schwann-like cells (SLCs). Xenografts were grafted in ovine sciatic nerves. Left sciatic nerves (20 mm) were excised from 10 sheep. Then, five sheep were grafted with 20 mm xenografts, and five were reimplanted with their nerve segment rotated 180° (AGT). RESULTS: All sheep treated with xenografts or AGT progressively recovered the strength, movement, and coordination of their intervened limb, which was still partial when the study was finished at sixth month postsurgery. At this time, numerous intrafascicular axons were observed in the distal and proximal graft extremes of both xenografts or AGTs, and submaximal nerve electrical conduction was observed. The xenografts and AGT-affected muscles appeared partially stunted. CONCLUSIONS: Xenografts and AGT were equally efficacious in starting PNI repair and justified further studies using longer observation times. The hallmarks from this study are that human xenogeneic acellular scaffolds were recellularized with allogenic SCL and were not rejected by the nonhuman receptors but were also as functional as AGT within a relatively short time postsurgery. Thus, this innovative approach promises to be more practical and accessible than AGT or allogenic allografts and safer than AGT for PNI repair.
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BACKGROUND: Loss of volume is perhaps the most frustrating problem of fat grafting. The process of fat grafting depends on different variables such as harvesting, processing, and injection techniques. Results between studies that evaluate the effect of the cannula size on fat graft survival have been controversial. However, the role of the fenestration area of the cannula has not been described. METHODS: Four custom-made cannulas with a single fenestration were used for this study. Cannulas vary in diameter and area of the fenestration. Healthy patients seeking primary liposuction of the abdomen for aesthetic reasons were included. Lipoaspiration was performed in a clockwise pattern, and the order of the cannulas was rotated. Negative pressure was maintained at 0.8 atm at all times. Ten ml of fat, obtained from the suction tube, was poured into 20-ml conical centrifugal tubes for further processing. One gram of lipoaspirate was extracted from each sample, and acridine orange stain was added. Adipocytes were extracted, extended in a frotis, and observed by a histologist (masked fashion) under fluorescence microscopy. Viability was reported in percentages per sample. RESULTS: The overall viability was 64.75% ± 18.58. The viability of the obtained samples ranged from 66.51± 20.66 % to 62.83 ± 18.1. In further analysis, comparing the viability according to the shaft diameter and fenestration area, there was no significant difference among groups. CONCLUSIONS: Neither the diameter of the cannula nor the size of the fenestrations are determining factors to affect the viability of the adipocytes. NO LEVEL ASSIGNED: This journal requires that authors assign a level of evidence to each submission to which Evidence-Based Medicine rankings are applicable. This excludes Review Articles, Book Reviews, and manuscripts that concern Basic Science, Animal Studies, Cadaver Studies, and Experimental Studies. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .
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Lipectomia , Adipócitos/transplante , Animais , Cânula , Estética , Sobrevivência de Enxerto , Humanos , Lipectomia/métodosRESUMO
OBJETIVO: Evaluar los resultados estéticos y funcionales, así como el grado de satisfacción, posteriores a la reconstrucción de defectos de la extremidad inferior en niños con colgajo de dorsal ancho preservador del músculo como una alternativa para estos casos. MÉTODO: Se incluyeron pacientes menores de 18 años con defectos en la extremidad inferior tratados en un periodo de 3 años. Se realizó colgajo dorsal ancho preservador de músculo en todos los pacientes. Se valoraron la apariencia estética, la fuerza muscular del área donadora y la función en el área receptora a los 3 meses de realizado el colgajo. RESULTADOS: Se realizaron 13 colgajos de dorsal ancho preservadores de músculo. La apariencia estética de las áreas donadora y receptora fue satisfactoria en la mayoría de los casos. La mayoría de los pacientes presentaron una fuerza muscular normal (M5) en el sitio donador y pudieron deambular. CONCLUSIONES: El colgajo de dorsal ancho preservador de músculo tiene un grado de satisfacción muy elevado, excelente simetría y preservación de la función muscular del sitio donador. Es una técnica ideal en defectos tisulares importantes de la extremidad inferior en la población pediátrica. OBJECTIVE: To evaluate the aesthetic and functional outcomes as well as the degree of postoperative satisfaction of the lower limb's defects reconstruction with a muscle-sparing latissimus dorsi flap in children in order to propose this kind of reconstruction as a secure alternative. METHOD: In this study were included patients under 18 years with lower limb's defects treated over a period of 3 years. A muscle-sparing latissimus dorsi flaps was performed in all patients. After three months the flap was performed, it was evaluated the donor's area muscular strength, recipient area function and aesthetic appearance. RESULTS: They were made 13 muscle-sparing latissimus dorsi flaps. In most cases, the donor and recipient area has satisfactory aesthetic appearance, most of the patients had a normal muscular strength (M5) in donors area and were able to walk. CONCLUSIONS: The reconstruction using a muscle-sparing latissimus dorsi flap has a very high level of satisfaction, excellent symmetry, and preservation of donor area muscle function. It is an ideal technique for major tissue defects of lower limb in children.
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Retalhos Cirúrgicos , Adolescente , Criança , Humanos , Estudos RetrospectivosRESUMO
OBJETIVO: Evaluar el efecto de la refrigeración en la apoptosis y la viabilidad del lipoaspirado en las primeras 2 horas después de la toma. MÉTODO: Se incluyeron 20 pacientes que fueron sometidas a una liposucción del abdomen por razones estéticas. Se obtuvieron 5 ml de grasa y se procesaron para su estudio. La viabilidad se determinó usando azul tripano. La apoptosis se determinó usando el ensayo TUNEL. RESULTADOS: Todas las pacientes eran mujeres, con una edad media de 36.5 años (rango: 21-67). Con respecto a la viabilidad, en el tiempo 0, en el grupo control fue del 59.08 ± 24% y en el grupo de refrigeración fue del 60.96 ± 22%; a los 60 minutos, los valores fueron del 50.82 ± 21% y el 55 ± 32.6%, respectivamente (p = 0.74); y a los 120 minutos, fueron del 42.69 ± 20.85% y el 50.33 ± 21%, respectivamente. En cuanto a la apoptosis, el porcentaje de células apoptóticas en el tiempo 0 fue del 37.87 ± 9.7% para el grupo de control y del 34.28 ± 9.74% para las muestras refrigeradas; a los 60 minutos, del 51.11 ± 8.64% y el 45.94 ± 9.15%, respectivamente; y a los 120 minutos, del 62.97 ± 13.33% y el 55.81 ± 9.45%, respectivamente. CONCLUSIONES: Refrigerar el lipoaspirado a 4 °C disminuyó la mortalidad y la apoptosis de los adipocitos en menos del 10% en las primeras 2 horas desde la toma.
OBJECTIVE: To evaluate the effect of refrigeration in the apoptosis and viability of the lipoaspirate in the first 2 h after harvesting. METHODS: 20 consecutive patients who underwent liposuction from the abdomen for esthetic reasons were included. 5 ml of fat were obtained and processed for study. The viability was obtained using trypan blue. Apoptosis was determined using TUNEL assay. RESULTS: All patients were female with a median age of 36.5 (21-67) years. On regard of the viability, at time 0, the viability in the control group was 59.08 ± 24% and 60.96 ± 22% in the refrigeration group. At 60 min, the values were 50.82 ± 21% versus 55 ± 32.6% (p = 0.74) and a 120 min, 42.69 ± 20.85% and 50.33 ± 21% respectively. On regard of apoptosis, the percentage of apoptotic cells at time 0 was 37.87 ± 9.7% for the control group and 34.28 ± 9.74% for refrigerated samples. At 60 min 51.11 ± 8.64% versus 45.94 ± 9.15% and at 120 min, 62.97 ± 13.33% versus 55.81 ± 9.45% respectively. CONCLUSIONS: Refrigerating the lipoaspirate at 4 °C decreased the mortality and apoptosis of the adipocytes in <10% within the first 2 h from harvesting.
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Adipócitos/fisiologia , Apoptose , Lipectomia , Adulto , Idoso , Sobrevivência Celular , Feminino , Humanos , Pessoa de Meia-Idade , Refrigeração , Fatores de Tempo , Adulto JovemRESUMO
BACKGROUND: The effect of decantation time on viability and apoptosis in adipocytes has not been described. The objective of the study was to describe viability and apoptosis in adipocytes up to 2 h after harvesting. METHODS: Twenty patients who underwent esthetic liposuction from the abdomen were included. The lipoaspirate was obtained from the infra-umbilical area with the tumescent technique. Liposuction was performed with a 60-ml syringe and a 3-ml cannula. Lipoaspirates were centrifuged at 50 g for 5 min at 0, 60 and 120 min after harvesting. One gram of fat was digested with 0.1% type 1 collagenase and incubated at 37 degrees for 30 min. Adipocytes were counted on 10 random microscopic fields. Apoptosis was determined by TUNEL assay. A fluorescence microscope was used to visualize the staining nuclei and cells. RESULTS: Regarding viability, immediately after harvesting, 57.6 ± 18.9% of the cells were viable, whereas 60 min after liposuction the viability decreased to 51.62 ± 8.8% and 120 min after liposuction the percentage of viable cells was 46.8 ± 16.9%. The percentage of apoptotic cells at time 0 was 38.2 ± 8.0%, whereas it was 51.24 ± 8.1% at 60 min and 62.9 ± 16.1% at 120 min after collection. CONCLUSIONS: Apoptosis and mortality of adipocytes after liposuction increase directly proportional to the time of decantation. Lipoinjection should be performed as soon as possible after harvesting. NO LEVEL ASSIGNED: This journal requires that authors assign a level of evidence to each submission to which Evidence-Based Medicine rankings are applicable. This excludes Review Articles, Book Reviews, and manuscripts that concern Basic Science, Animal Studies, Cadaver Studies, and Experimental Studies. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .