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3.
Int J Biomater ; 2018: 8040893, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29483927

RESUMEN

Pelvic organ prolapse (POP) has borrowed principles of treatment from hernia repair and in the last two decades we saw reinforcement materials to treat POP with good outcomes in terms of anatomy but with alarming complication rates. Polypropylene meshes to specifically treat POP have been withdrawn from market by manufactures and a blank space was left to be filled with new materials. Macroporous monofilament meshes are ideal candidates and electrospinning emerged as a reliable method capable of delivering production reproducibility and customization. In this review, we point out some pathways that seem logical to be followed but have been only researched in last couple of years.

4.
J Biomater Appl ; 30(10): 1578-88, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26896234

RESUMEN

There is an urgent clinical need for better synthetic materials to be used in surgical support of the pelvic floor. The aim of the current study was to construct biodegradable synthetic scaffolds that mimic the three-dimensional architecture of human fascia, which can integrate better into host tissues both mechanically and biologically. Therefore, four different polylactic acid (PLA) scaffolds with various degrees of fibre alignment were electrospun by modifying the electrospinning parameters. Physical and mechanical properties were assessed using a BOSE electroforce tensiometer. The attachment, viability and extracellular matrix production of adipose-derived stem cells cultured on the polylactic acid scaffolds were evaluated. The bulk density of the scaffolds decreased as the proportion of aligned fibres increased. Scaffolds became stronger and stiffer with increasing amounts of aligned fibres as measured along the axis parallel to the fibre alignment. In addition, more total collagen was produced on scaffolds with aligned fibres and was organised in the direction of the aligned fibres. In conclusion, the electrospinning technique can be easily modified to develop biodegradable scaffolds with a spectrum of mechanical properties allowing extracellular matrix organisation towards human-like fascia.


Asunto(s)
Prolapso de Órgano Pélvico/terapia , Poliésteres/química , Células Madre/citología , Ingeniería de Tejidos/métodos , Andamios del Tejido/química , Incontinencia Urinaria de Esfuerzo/terapia , Tejido Adiposo/citología , Materiales Biocompatibles , Células Cultivadas , Colágeno/metabolismo , Matriz Extracelular/metabolismo , Humanos , Ensayo de Materiales , Células Madre/metabolismo
5.
Biomed Res Int ; 2015: 968087, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25977927

RESUMEN

Stress urinary incontinence (SUI) and pelvic organ prolapse (POP) are major health issues that detrimentally impact the quality of life of millions of women worldwide. Surgical repair is an effective and durable treatment for both conditions. Over the past two decades there has been a trend to enforce or reinforce repairs with synthetic and biological materials. The determinants of surgical outcome are many, encompassing the physical and mechanical properties of the material used, and individual immune responses, as well surgical and constitutional factors. Of the current biomaterials in use none represents an ideal. Biomaterials that induce limited inflammatory response followed by constructive remodelling appear to have more long term success than biomaterials that induce chronic inflammation, fibrosis and encapsulation. In this review we draw upon published animal and human studies to characterize the changes biomaterials undergo after implantation and the typical host responses, placing these in the context of clinical outcomes.


Asunto(s)
Materiales Biocompatibles/uso terapéutico , Prolapso de Órgano Pélvico/cirugía , Procedimientos de Cirugía Plástica , Incontinencia Urinaria de Esfuerzo/cirugía , Femenino , Humanos , Diafragma Pélvico/fisiopatología , Diafragma Pélvico/cirugía , Prolapso de Órgano Pélvico/patología , Mallas Quirúrgicas , Resultado del Tratamiento , Incontinencia Urinaria de Esfuerzo/patología
6.
Int Urol Nephrol ; 47(7): 1075-84, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25913053

RESUMEN

INTRODUCTION: Robotic assistance may provide for distinct technical advantages over conventional laparoscopic technique. The goals of this study were (1) to objectively evaluate the difference in the learning curves by novice and expert surgeons in performing fundamental laparoscopic skills using conventional laparoscopic surgery (CLS) and robotic-assisted laparoscopic surgery (RALS) and (2) to evaluate the surgeons' frustration level in performing these tasks. METHODS: Twelve experienced and 31 novices in laparoscopy were prospectively evaluated in performing three standardized laparoscopic tasks in five consecutive, weekly training sessions. Analysis of the learning curves was based on the magnitude, rate, and quickness in performance improvement. The participant's frustration and mood were also evaluated during and after every session. RESULTS: For the novice participants, RALS allowed for shorter time to task completion and greater accuracy. However, significant and rapid improvement in performance as measured by magnitude, rate, and quickness at each session was also seen with CLS. For the experienced surgeons, RALS only provided a slight improvement in performance. For all participants, the use of RALS was associated with less number of sessions in which they felt frustrated, less number of frustration episodes during a session, lower frustration score during and after the session, and higher good mood score. CONCLUSION: The advantages of RALS may be of most benefit when doing more complex tasks and by less experienced surgeons. RALS should not be used as a replacement for CLS but rather in specific situations in which it has the greatest advantages.


Asunto(s)
Competencia Clínica , Educación de Postgrado en Medicina/métodos , Capacitación en Servicio/métodos , Laparoscopía , Médicos/psicología , Procedimientos Quirúrgicos Robotizados , Estudiantes de Medicina/psicología , Análisis y Desempeño de Tareas , Humanos , Laparoscopía/educación , Laparoscopía/métodos , Curva de Aprendizaje , Evaluación de Necesidades , Procedimientos Quirúrgicos Robotizados/educación , Procedimientos Quirúrgicos Robotizados/métodos , Estrés Psicológico/diagnóstico , Estrés Psicológico/etiología
7.
Biomater Sci ; 1(9): 942-951, 2013 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-32481963

RESUMEN

Many biomaterial scaffolds have been developed for use in tissue engineering usually for populating with a single cell-type. In this study we demonstrate the production of bilayer and trilayer nanofibrous/microfibrous biodegradable scaffolds suitable for the support, proliferation and yet segregation of different tissues - here used to separate soft tissue from bone forming tissue and keratinocytes from fibroblasts. Essentially we describe a nanofibre barrier membrane which is permeable to nutrients coupled with attached microfibers (either on one side or both sides) to support the proliferation of different cell types either side but prevents migration of cells across the barrier. Such membranes would be suitable for guided tissue regeneration in areas where one wishes to support both soft and hard tissues but keep them separated. We describe a sterile bilayer membrane electrospun from polyhydroxybutyrate-co-hydroxyvalerate (PHBV) (nanofibres) and polylactic acid (PLA) or poly ε-caprolactone (PCL) (microfibres) and a trilayer membrane electrospun in layers of PLA, PHBV, then PLA. These membranes are biocompatible, biodegradable and capable of supporting two different cell populations.

8.
J Pediatr Urol ; 8(4): 379-85, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21955529

RESUMEN

PURPOSE: Reporting on the laparoscopic technique for adrenal disease in children and adolescents has been limited. We review here our experience with laparoscopic adrenal surgery in children. PATIENTS AND METHODS: 19 laparoscopic unilateral adrenalectomies were performed in 10 girls and 7 boys (mean age 3.9 years) during 1998-2011. The clinical diagnosis before surgery was virilizing tumor (n = 8), pheochromocytoma (n = 3), nonfunctioning solid adrenal tumor (n = 3), mixed adrenocortical tumor (n = 2), cystic adrenal mass (n = 1). Unilateral adrenal lesions were 20-65 mm at the longest axis on computerized tomography (12 right side, 7 left side). RESULTS: The final clinicopathological diagnosis was cortical adenoma (n = 9), pheochromocytoma (n = 3, bilateral in two), neuroblastoma (n = 1), ganglioneuroblastoma (n = 1), ganglioneuroma (n = 1), adrenocortical carcinoma (n = 1), benign adrenal tissue (n = 1). Average operative time was 138.5 min (range 95-270). Blood transfusion was required in one case (5%). No conversion to open surgery was required and no deaths or postoperative complications occurred. Average hospital stay was 3.5 days (range 2-15). Average postoperative follow-up was 81 months (range 2-144). Two contralateral metachronic pheochromocytomas associated with von Hippel-Lindau syndrome occurred, treated with partial laparoscopic adrenalectomy (one without postoperative need of cortisone replacement therapy). CONCLUSIONS: Laparoscopic adrenalectomy is a feasible procedure that produces good results. It can be used safely to treat suspected benign and malignant adrenal masses in children with minimal morbidity and short hospital stay.


Asunto(s)
Neoplasias de las Glándulas Suprarrenales/patología , Neoplasias de las Glándulas Suprarrenales/cirugía , Adrenalectomía/métodos , Laparoscopía/métodos , Recurrencia Local de Neoplasia/patología , Adolescente , Adrenalectomía/efectos adversos , Biopsia con Aguja , Niño , Preescolar , Estudios de Cohortes , Femenino , Estudios de Seguimiento , Humanos , Inmunohistoquímica , Laparoscopía/efectos adversos , Tiempo de Internación , Imagen por Resonancia Magnética/métodos , Masculino , Procedimientos Quirúrgicos Mínimamente Invasivos/efectos adversos , Procedimientos Quirúrgicos Mínimamente Invasivos/métodos , Recurrencia Local de Neoplasia/fisiopatología , Dolor Postoperatorio/fisiopatología , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/fisiopatología , Estudios Retrospectivos , Medición de Riesgo , Factores de Tiempo , Resultado del Tratamiento , Ultrasonografía Doppler
9.
Rev. bras. reumatol ; 42(5): 295-305, set.-out. 2002. ilus, graf
Artículo en Portugués | LILACS | ID: lil-413669

RESUMEN

Objetivos: As doenças difusas do tecido conjuntivo (DDTC) são enfermidades de etiologia e patogênese desconhecidas, responsáveis pelo desenvolvimento de manifestações clínicas multissistêmicas, e do ponto de vista laboratorial caracterizadas pela presença de auto-anticorpos dirigidos contra diferentes componentes celulares. Modelos experimentais que reproduzem manifestações clínicas, histológicas e laboratoriais similares às observadas em humanos são extremamente importantes no estudo da patogênese e abordagem terapêutica destas enfermidades. Métodos: Descrevemos um modelo inédito de autoimunidade desenvolvido em coelhos pela imunização com colágeno tipo V, fibrila com características peculiares em sua síntese, que confere grande antigenicidade à sua molécula e participa de processos de reparação, diferenciação e proliferação celular. Analisamos as alterações morfológicas promovidas em diferentes órgãos de coelhos sensibilizados com o colágeno tipo V e sacrificados após 75 e 120 dias do início da imunização. Resultados: Verificou-se presença de vasculite em pulmões, especialmente nos lobos basais, caracterizados pelo espessamento da íntima vascular, infiltrado celular por eosinófilos e linfócitos, além de depósito de colágeno na região subendotelial, perivascular, peribrônquica e interstício pulmonar. No coração observou-se depósito de colágeno entre as fibras cardíacas e vasculite. No esôfago notou-se diminuição do lúmen, depósito de colágeno em nível submucoso e perivascular. Alterações nos glomérulos renais, como discreta proliferação mesangial e espessamento da membrana basal, e moderado depósito de colágeno intersticial, foram aspectos morfológicos observados nos rins. Na sinóvia houve proliferação de células epiteliais e depósito de colágeno subepitelial. Estudo histológico da cartilagem articular revelou aumento da celularidade e remodelamento da matriz extracelular. Conclusões: Neste trabalho descrevemos um novo modelo experimental no qual um fator exógeno promoveu lesão patológica em múltiplos órgãos de um animal sadio. As alterações morfológicas observadas nos levam a propor que este seja um modelo experimental que reproduz achados clínicos e laboratoriais semelhantes aos da esclerodermia.


Asunto(s)
Conejos , Animales , Autoanticuerpos , Autoinmunidad , Colágeno Tipo V , Tejido Conectivo
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