Estabelecimento de protocolo de glicerolação de membranas amnióticas para uso como curativo biológico / Establishing protocol glicerolação of amniotic membranes for use as a biological dressing

Introdução: Pesquisadores têm procurado explorar várias alternativas terapêuticas (substitutos dérmicos), biológicas ou sintéticas, capazes de assegurar condições ideais ao leito da ferida que favoreça o processo de cicatrização. Uma opção de substituto dérmico menos oneroso é o uso de membranas amnióticas. Os curativos constituídos de âmnion formam uma barreira protetora contra as bactérias ambientais, aceleram a reepitelização das lesões e diminuem a dor local. Objetivo: Estabelecer protocolo de processamento de membranas amnióticas em altas concentrações de glicerol. Método: Foram obtidas três amostras de membranas amnióticas, que preenchiam os critérios de inclusão e que a gestantes concordaram em ceder o material para pesquisa. Resultados: Os exames de cultura do material no momento da captação demonstraram ausência de crescimento bacteriano ou de fungos. As sorologias das pacientes foram todas negativas. Conclusão: Neste trabalho, buscamos estabelecer um protocolo de conservação de membranas amnióticas baseado na glicerolação, pois se trata de um método de baixo custo, relativamente simples e de fácil estocagem do material. Este método apresenta como desvantagem a sua alta toxicidade celular, resultando em destruição das células do tecido, porém preserva a integridade estrutural tecidual, conforme demonstrado nos resultados macroscópicos e microscópicos obtidos neste estudo.

Introduction: Researchers have attempted to explore various alternative therapies (dermal substitutes), biological or synthetic, capable of providing ideal conditions to the wound bed to promote the healing process. An option of dermal substitute less costly is the use of amniotic membranes. Dressings consist of amnion forms a protective barrier against environmental bacteria, accelerate reepithelialization of lesions and reduce local pain. Objective: To establish protocol processing of membranes in high concentrations of glycerol. Methods: Three samples were obtained from amniotic membranes who met the inclusion criteria and that the women agreed to donate the material for research. Results: The examinations of material culture at the time of capture showed no bacterial or fungal growth. The serology of the patients was all negative. Conclusion: In this study, we establish a protocol for the conservation of membranes based on glycerol because it is a low-cost, relatively simple and easy storage of the material. This method presents the disadvantage of its high cell toxicity, resulting in destruction of tissue cells, but preserves the structural integrity of tissue as shown in the microscopic and macroscopic results of this study.

The importance of ethic in the field of human tissue banking.

A tissue bank is accountable before the community in fulfilling the expectations of tissue donors, their families and recipients. The expected output from the altruistic donation is that safe and high quality human tissue grafts will be provided for the medical treatment of patients. Thus, undertakings of tissue banks have to be not only authorised and audited by national competent health care authorities, but also comply with a strong ethical code, a code of practices and ethical principles. Ethical practice in the field of tissue banking requires the setting of principles, the identification of possible deviations and the establishment of mechanisms that will detect and hinder abuses that may occur during the procurement, processing and distribution of human tissues for transplantation. The opinions and suggestions manifested by the authors in this paper may not be necessarily a reflection of those within the institutions or community they are linked to.

Role of keratinocytes in wound contraction: an impact assessment using a model of collagen matrix populated with fibroblasts / Papel do queratinócito na contração da ferida: avaliação de impacto usando um modelo de matriz de colágeno povoada por fibroblastos

BACKGROUND: The possible participation of keratinocytes in wound remodeling has been widely studied. This study investigated the impact of keratinocytes in wound contraction. METHODS: Murine type I collagen gels populated by human fibroblasts and seeded with human keratinocytes on the surface to form a dermo-epidermal equivalent were used as the study group. Collagen gels populated by only fibroblasts were used as the control group. The criteria for the preparation and storage of gels were similar for both groups. RESULTS: An evident and statistically significant increase in gel contraction was observed in samples populated by keratinocytes compared to the control group. CONCLUSIONS: These results suggest that keratinocytes not only modulate fibroblast proliferation but also play an active role in wound contraction per se. Further research on the mechanisms involved in the communication pathways between cells and between cells and the matrix shall be assessed from the perspective of keratinocyte participation in wound healing and pathologic scarring.

INTRODUÇÃO: A eventual participação de queratinócitos na remodelagem da ferida tem sido estudada há muito tempo. Este trabalho investigou o impacto dos queratinócitos na contração da ferida. MÉTODO: Foi utilizado gel de colágeno tipo I murino povoado por fibroblastos humanos com queratinócitos humanos semeado na superfície (grupo estudo), formando um equivalente dermoepidérmico. Géis de colágeno povoado apenas por fibroblastos foram utilizados como grupo controle. Os critérios de confecção e armazenagem dos géis foram iguais para ambos os grupos. RESULTADOS: Houve aumento evidente e estatisticamente significante na contração de gel das amostras povoadas por queratinócitos, em comparação ao grupo controle. CONCLUSÕES: Esses resultados sugerem que os queratinócitos não só podem modular a proliferação de fibroblastos, mas também, por si só, desempenhar papel ativo na contração da ferida. Novas investigações sobre mecanismos envolvidos nas vias de comunicação entre células e entre célula e matriz devem ser avaliadas sob o ponto de vista de participação dos queratinócitos na cicatrização de feridas e formação de cicatrizes patológicas.

Ultrastructural evaluation of human keratinocyte growth and differentiation on a fibrin substrate.

PURPOSE: In order to circumvent several difficulties that have been met in the routine use of the in vitro keratinocyte cultures using the standard procedure described by Rheinwald and Green, and obtain a more resilient and the least possible immunogeneic skin substitute for a future clinical application, this work studied a new keratinocyte culture system, which envisages the utilization of a fibrin substrate in association with high densities of human keratinocytes. METHODS: Through light and transmission electron microscopy and immunohistochemical assays, long-term proliferative and differentiative characteristics of keratinocytes cultured onto a fibrin gel under immerse and air-liquid interface culture conditions were evaluated. RESULTS: Despite the absence of a dermal substitute, the results demonstrated that the proposed composite was constituted of a transparent and elastic fibrin film covered by a well-attached, multistratified epithelium with morphological characteristics that resemble human epidermis, including the neoformation, albeit incomplete, of the basement membrane. CONCLUSIONS: Increased mechanical resistance due to the presence of an easy handling substrate, the delivery of nonclonfluent keratinocytes as well as the removal of animal-derived cells from the culture system suggest its potential use for future transplantation purposes.

Ultrastructural evaluation of human keratinocyte growth and differentiation on a fibrin substrate / Avaliação ultraestrutural do crescimento e da diferenciação de queratinócitos sobre um substrato de fibrina

PURPOSE: In order to circumvent several difficulties that have been met in the routine use of the in vitro keratinocyte cultures using the standard procedure described by Rheinwald and Green, and obtain a more resilient and the least possible immunogeneic skin substitute for a future clinical application, this work studied a new keratinocyte culture system, which envisages the utilization of a fibrin substrate in association with high densities of human keratinocytes. METHODS: Through light and transmission electron microscopy and immunohistochemical assays, long-term proliferative and differentiative characteristics of keratinocytes cultured onto a fibrin gel under immerse and air-liquid interface culture conditions were evaluated. RESULTS: Despite the absence of a dermal substitute, the results demonstrated that the proposed composite was constituted of a transparent and elastic fibrin film covered by a well-attached, multistratified epithelium with morphological characteristics that resemble human epidermis, including the neoformation, albeit incomplete, of the basement membrane. CONCLUSIONS: Increased mechanical resistance due to the presence of an easy handling substrate, the delivery of nonclonfluent keratinocytes as well as the removal of animal-derived cells from the culture system suggest its potential use for future transplantation purposes.

OBJETIVO: Com o intuito de contornar diversas dificuldades encontradas no uso rotineiro de queratinócitos cultivados in vitro pela técnica descrita por Rheinwald e Green, e obter um substituto cutâneo mais resistente e o menos imunogênico possível para futuras aplicações clínicas, este trabalho avaliou um novo sistema de cultura de queratinócitos que prevê a utilização de um substrato de fibrina em associação com queratinócitos humanos em alta densidade. MÉTODOS: Através de microscopia óptica e eletrônica e análise imunohistoquímica, foram avaliadas as características proliferativas e de diferenciação em longo prazo de queratinócitos cultivados em condição imersa e na interface ar-líquido. RESULTADOS: Apesar da ausência de um substituto dérmico, foi demonstrado que o composto proposto constituiu-se de um substrato de fibrina transparente e elástico coberto por epitélio multi-estratificado, bem aderido, com características morfológicas semelhantes à epiderme humana, incluindo a neo-formação, embora incompleta, da membrana basal. CONCLUSÕES: A maior resistência mecânica com a presença de um substrato de fácil manuseio, a possível liberação de queratinócitos não-confluentes, e a remoção de células com origem animal dos sistemas de cultura sugerem que o composto proposto neste estudo apresenta grande potencial para uso clínico futuro.

Estabelecimento de protocolo de glicerolização de membranas amnióticas para uso como curativo biológico / Establishment of amniotic membranes glycerolization protocol for use as biological dressing

Introdução: Pesquisadores têm procurado explorar várias alternativas terapêuticas, biológicas ou sintéticas, capazes de assegurar condições ideais ao leito da ferida, que favoreçam o processo de cicatrização. Uma opção menos onerosa é o uso de membranas amnióticas. Os curativos constituídos de âmnion formam uma barreira protetora contra as bactérias ambientais, aceleram a reepitelização das lesões e diminuem a dor local. Objetivo: O objetivo deste trabalho foi estabelecer protocolo de processamento de membranas amnióticas em altas concentrações de glicerol. Método: Foram obtidas 3 amostras de membranas amnióticas, que preenchiam os critérios de inclusão e que as gestantes concordaram em ceder o material para pesquisa. Resultados: Os exames de cultura do material no momento da captação mostravam ausência de crescimento bacteriano ou de fungos. As sorologias das pacientes eram todas negativas. Conclusão: Nesse trabalho, buscamos estabelecer um protocolo de conservação de membranas amnióticas baseado na glicerolização, pois se trata de um método de baixo custo, relativamente simples e de fácil estocagem do material. Apresenta como desvantagem a sua alta toxicidade celular, resultando em destruição das células do tecido, porém preserva a integridade estrutural tecidual, conforme demonstrado em nossos resultados macroscópicos e microscópicos.

Background: Researchers have attempted to explore various alternative therapies, biological or synthetic, capable of providing ideal conditions to the wound bed to promote the healing process. An option less costly is the use of amniotic membranes. Dressings consist of amnion forms a protective barrier against environmental bacteria, accelerate reepithelialization of lesions and reduce local pain. Objective: The aim of this study was to establish protocol processing of membranes in high concentrations of glycerol. Methods: Three samples were obtained from amniotic membranes who met the inclusion criteria and that the pregnant agreed to donate the material for research. Results: The examinations of material culture at the time of capture showed no bacterial or fungal growth. The serology of the patients was all negative. Conclusion: In this paper, we established a protocol for the conservation of membranes based on glycerol because it is a low-cost, relatively simple and easy storage of the material. Presents the disadvantage of its high cell toxicity, resulting in destruction of tissue cells, but preserves the structural integrity of tissue as shown in our results the microscopic and macroscopic.

Pentoxifylline modifies three-dimensional collagen lattice model contraction and expression of collagen types I and III by human fibroblasts derived from post-burn hypertrophic scars and from normal skin.

Fibroblasts are thought to be partially responsible for the persisting contractile forces that result in burn contractures. Using a monolayer cell culture and fibroblast populated collagen lattice (FPCL) three-dimensional model we subjected hypertrophic scar and non-cicatricial fibroblasts to the antifibrogenic agent pentoxifylline (PTF - 1mg/mL) in order to reduce proliferation, collagen types I and III synthesis and model contraction. Fibroblasts were isolated from post-burn hypertrophic scars (HSHF) and non-scarred skin (NHF). Cells were grown in monolayers or incorporated into FPCL's and exposed to PTF. In monolayer, cell number proliferation was reduced (46.35% in HSHF group and 37.73% in NHF group, p<0.0001). PTF selectively inhibited collagen III synthesis in the HSHF group while inhibition was more evident to type I collagen synthesis in the NHF group. PTF also reduced contraction in both (HSHF and NHF) FPCL.

Tratamento de cicatrizes hipocrômicas pós-queimadura com transplante de melanócitos cultivados in vitro / Transplant of cultivated melanocytes for the treatment of hypochromic

Introdução: As cicatrizes hipocrômicas pós-queimadura são um problema frequente, quecausa aos pacientes constrangimento social e sofrimento psicológico, uma vez que podemser bastante evidentes, graças aos contrastes de cores de pele que surgem ao seu redor (diferentestons de pele entre a pele normal e a área vizinha à cicatriz - normalmente hipercrômica,e a cicatriz pós-queimadura, hipocrômica). As opções de tratamentos atuais para talproblema não são muito eficientes; estão hoje disponíveis: a maquiagem – que apresenta oinconveniente de sair com o passar das horas, ou a tatuagem, que muitas vezes não acompanhao tom da pele normal. Método: Neste trabalho, utilizamos epitélios de queratinócitosautólogos cultivados in vitro como veículo de transporte de melanócitos funcionantes parao tratamento dessas áreas cicatriciais hipocrômicas resultantes de queimaduras. Estes epitélioscultivados serviram como instrumento para a repopulação definitiva destas áreas comcélulas produtoras de pigmento melânico. O método empregado incluiu o cultivo in vitro deepitélios autólogos constituídos por queratinócitos e melanócitos funcionantes, a abrasãosuperficial das áreas a serem tratadas, objetivando a remoção de epiderme hipocrômica, eo transplante dos enxertos autólogos cultivados. Resultados: Os resultados obtidos com aintegração destes epitélios cultivados, ou seja, a restauração e a repigmentação das áreashipocrômicas, foram avaliados por meio do uso de tabelas colorimétricas e biópsias, que demonstrarama repigmentação das cicatrizes e a persistência dos melanócitos transplantados.

Background: Post-burn hypochromic scars can be the subject of great personal sufferingto their victims. Due to the color contrast between the normal and affected skins, they arevisible lesions that embarrass the injured subjects and limit their social performance. Theavailable treatment options in the present days are insufficient, and tend to evolve withpoor results. Methods: We present in this paper the use of in vitro cultivated keratinocyteepithelium as a vehicle for the transplantation of working melanocytes to repopulate thesehypochromic areas in four patients. Results: The results were evaluated with the use of colortables and skin biopsies that allowed us to clearly demonstrate the partial repigmentationof the scar areas and the integration of the transplanted melanocytes. The repigmented skinaverage after 3 and 6 months of the procedure was of 30.52% and 51.66%, respectively. Ifwe consider the low-morbidity of the procedure, these results are already very encouraging,but we strongly believe that technical refinements could allow even better results.

Estudo in vitro dos efeitos do bloqueador do canal decálcio (verapamil) sobre a biossíntese e contração damatriz extracelular / In vitro study of effects of calcium channel blocker (verapamil) on biosyntheses

Introdução: A adequada formação do tecido de granulação depende do equilíbrio entre abiossíntese e a degradação da matriz extracelular (MEC). A síntese excessiva de colágeno e adeficiente remodelação da MEC podem induzir o aparecimento de lesões dérmicas tipo quelóidese cicatrizes hipertróficas. Método: No presente estudo, utilizamos fibroblastos dérmicoshumanos povoados em gel de colágeno I, tratados ou não pelo bloqueador de canal de cálcio(verapamil). Uma vez no gel de colágeno, a morfologia tridimensional dos fibroblastos foianalisada por microscopia confocal e em cortes corados por hematoxilina & eosina. A atividadeda colagenase (MMP-I) foi determinada por “immunoblot” do meio condicionado. Resultados:Observamos neste estudo maior contração do gel de colágeno povoado por fibroblastoscontrole, quando comparado ao gel povoado por fibroblastos tratados com verapamil. A maiorcontração demonstrada pelos fibroblastos controle foi relacionada à reorientação das fibrascolágenas, à organização dos filamentos de actina e aos níveis de cálcio citosólico. Observamos,também, que o verapamil aumenta a secreção de colagenase. Conclusão: Concluímos que overapamil, ao alterar o metabolismo celular do cálcio, exerce influência sobre a contração daMEC e produção de proteases, com consequente efeito sobre o desenvolvimento de afecçõescicatriciais, como quelóides e cicatrizes hipertróficas.

Background: The appropriate formation of the granulation tissue depends on the balancebetween the biosyntheses and the degradation of the extracellular matrix (EM). The excessivesynthesis of collagen and the deficient degradation of the EM might cause dermal lesions suchas keloids and hypertrophic scars. Methods: In this study we used an experimental modelwhere collagen gels populated by dermal human fibroblast underwent progressive contraction.Fluorescence preparations were studied by confocal microscopy. Collagenase activity (MMPI)was determined in conditioned medium from fibroblasts using immunoblot. Results: Thisstudy showed a greater contraction of the gels populated with control fibroblasts per the timestudied in relation to the gels populated with fibroblasts treated with verapamil. Perhaps thishigher contracting ability is involved with actin organization and levels of cytosolic calcium.We also observed that verapamil increase the secretion of MMP-I. Conclusion: We concludethat cellular calcium metabolism appears to regulate EM production and contraction and thosehypertrophic disorders of wound healing (keloids and hypertrophic scars) may respond totherapy with calcium antagonist drugs (verapamil).

Comparison of two cellular harvesting methods for primary human oral culture of keratinocytes.

The possibility of obtaining transplantable oral epithelia opens new perspectives for oral treatments. Most of them are surgical, resulting in mucosal failures. As reconstructive material this in vitro epithelia would be also useful for other parts of the human body. Many researchers still use controversial methods; therefore it was evaluated and compared the efficiency of the enzymatic and direct explant methods to obtain oral keratinocytes. To this project oral epithelia fragments were used. This work compared: time needed for cell obtainment, best cell amount, life-span and epithelia forming cell capacity. The results showed the possibility to obtain keratinocytes from a small oral fragment and we could verify the advantages and peculiar restrictions. We concluded that under our conditions the enzymatic method showed the best results: in the cells obtaining time needed, cell amount and life-span. Both methods showed the same capacity to form in vitro epithelia.

The impact of the International Atomic Energy Agency (IAEA) program on radiation and tissue banking in Brazil.

Until 2000, efforts into organising tissue banks in Brazil had not progressed far beyond small "in house" tissue storage repositories, usually annexed to Orthopaedic Surgery Services. Despite the professional entrepreneurship of those working as part time tissue bankers in such operations, best practices in tissue banking were not always followed due to the lack of regulatory standards, specialised training, adequate facilities and dedicated personnel. The Skin Bank of the Plastic Surgery Department of the Hospital das Clinicas of Sao Paulo, the single skin bank in Brazil, was not an exception. Since 1956, restricted and unpredictable amounts of skin allografts were stored under refrigeration for short periods under very limited quality controls. As in most "tissue banks" at that time in Brazil, medical and nursing staff worked on a volunteer and informal basis undergoing no specific training. IAEA supported the implementation of the tissue banking program in Brazil through the regional project RLA/7/009 "Quality system for the production of irradiated sterilised grafts" (1998-2000) and through two interregional projects INT/6/049 "Interregional Centre of Excellence in Tissue Banking", during the period 2002-2004 and INT/6/052 "Improving the Quality of Production and Uses of Radiation Sterilised Tissue Grafts", during the period 2002-2004. In 2001-2002, the first two years of operation of the HC-Tissue Bank, 53 skin transplants were carried out instead of the previous 4-5 a year. During this period, 75 individuals donated skin tissue, generating approximately 90,000 cm(2) of skin graft. The IAEA program were of great benefit to Brazilian tissue banking which has evolved from scattered make shift small operations to a well-established, high quality tissue banking scenario.

Construção de equivalente dermo-epidérmico in vitro / Construction of an in vitro equivalent skin

Introdução: Dentre as diversas pesquisas realizadas na área de bioengenharia de tecidos, a criação in vitro de tecidos vivos tornase uma das mais promissoras formas de atuação científica. Neste caminho, cada vez mais têm sido descritos novos substitutos cutâneos para o tratamento de grandes lesões da pele. Bell et al. descreveram um modelo de matriz colágena tipo I contrátil após a adição de fibroblastos. Método: O presente estudo propõe a elaboração in vitro de um equivalente dermo-epidérmico composto por uma “derme” de colágeno povoada por fibroblastos, acompanhado de um epitélio de queratinócitos cultivados em sua superfície anterior no papel de “epiderme”. Além disso, estuda as alterações histológicas encontradas nos dias de cultura 4, 7, 14 e 21, avaliando a influência da interface ar-líquido na estratificação do epitélio. Resultados: Os resultados mostraram que houve a criação de um substituto dermo-epidérmico in vitro, com a formação de um epitélio com boa estratificação, sendo que o contato com o ar aumenta esta estratificação

A wound contraction experimental model for studying keloids and wound-healing modulators.

Preventing and treating hypertrophic and keloid scars is difficult because of the lack of knowledge about their genesis. Tissue repair can be studied with biocompatible matrices and ex vivo cultures of different cell types. We used an experimental model where collagen gels populated by human fibroblasts underwent progressive contraction, allowing the study of wound healing remodeling. The fibroblast-populated lattices showed the greater contraction of the gel populated by fibroblasts from keloids versus fibroblasts from normal skin. Moreover, fibroblast growth factor (FGF) and transforming growth factor beta (TGF-beta) involved in scar formation were added to the collagen gels populated by normal skin fibroblasts. TGF-beta caused an increase in gel contraction; FGF did not. The mean percentages of contraction of the gels populated by keloid fibroblasts were very similar to the percentages of gels populated by normal skin fibroblasts with added TGF-beta. These observations confirm the existing hypothesis that TGF-beta may be involved in keloid formation.

Tissue expander complications in plastic surgery: a 10-year experience.

INTRODUCTION: Tissue expanders have been of great value in plastic surgery. Tissue expansion was developed for a specific indication; however, within a very short time, the concept of tissue expansion found wide applicability. From 1990 to 1999, 315 expanders in 164 patients were utilized. A retrospective analysis of complications and prognostic factors for complications were done. METHODS: The indications for tissue expansion were burns (50%), trauma (32%), and sequelae of previous surgery (8.8%). The expanders were inserted most frequently in the scalp, trunk and neck. RESULTS: There were 22.2% of complications and the most common were expander exposure (50%), infection (24%) and bad function of the expander (12.8%). The present study revealed an increased rate of minor complications in the group of 0 to 10 years of age and an increased rate of major complications for face and neck expansions compared to trunk expansion. There were no increased complication rates for the other age and anatomic site groups, previous expansion, concomitant expansion and type of expander used. CONCLUSIONS: The outcomes from tissue expansion procedures done in our hospital are similar to those reported in the literature. Tissue expansion is a good and safe technique.

Tissue expander complications in plastic surgery: a 10-year experience

INTRODUCTION: Tissue expanders have been of great value in plastic surgery. Tissue expansion was developed for a specific indication; however, within a very short time, the concept of tissue expansion found wide applicability. From 1990 to 1999, 315 expanders in 164 patients were utilized. A retrospective analysis of complications and prognostic factors for complications were done. METHODS: The indications for tissue expansion were burns (50 percent), trauma (32 percent), and sequelae of previous surgery (8.8 percent). The expanders were inserted most frequently in the scalp, trunk and neck. RESULTS: There were 22.2 percent of complications and the most common were expander exposure (50 percent), infection (24 percent) and bad function of the expander (12.8 percent). The present study revealed an increased rate of minor complications in the group of 0 to 10 years of age and an increased rate of major complications for face and neck expansions compared to trunk expansion. There were no increased complication rates for the other age and anatomic site groups, previous expansion, concomitant expansion and type of expander used. CONCLUSIONS: The outcomes from tissue expansion procedures done in our hospital are similar to those reported in the literature. Tissue expansion is a good and safe technique

Sterilization of skin allografts by ionizing radiation.

The skin has a fundamental role in the viability of human body. In the case of extensive wounds, skin allografts provide an alternative to cover temporarily the damaged areas. After donor screening and preservation in glycerol 85%, the skin can be stored in a Skin Bank. Glycerol at this concentration has a bacteriostatic effect after certain time of preservation. On the other hand, skin sterilization by ionizing radiation may reduce the quarentine period for transplantation in patients. The objective of this work was to evaluate allograft sterilization using two sources of ionizing radiation. Through the analysis of stress-strain, it was intended to verify possible effects of the radiation on the structure of preserved grafts. Three groups of skin samples were selected. The first group was maintained in the initial conditions, not irradiated. The second was exposed to cobalt-60, while the third one was irradiated using an Dynamitron Accelerator JOB188 electron beam. The irradiation dose was 25 kGy for both tests. Both irradiation sources, and the Instron Universal Machine used for biomechanical experiments, are installed at the Centro de Tecnologia das Radiações/Instituto de Pesquisas Energéticas e Nucleares (São Paulo, Brazil). According to the preliminary results, biomechanical characteristics of the samples irradiated seem to be maintained with regard to the non irradiated group.

Reconstrucao mamaria imediata com o uso do retalho microcirurgico do musculo reto abdominal / Immediate breast reconstruction using the surgical flaps of the musculus rectus abdominis

O cancer mamario em estadiamento ainda e ocorrencia frequente na populacao feminina atendida por esta Instituicao. Consequentemente o tratamento cirurgico tende a ser agressivo e consequentemente mutilante. Diante do consenso quanto a importancia da mama para a auto-imagem positiva da mulher e da inalterabilidade do prognostico pela reconstrucao mamaria, esta tem sido proposta as pacientes na forma de diversas alternativas; entre estas, a reconstrucao da mama pelo uso do retalho musculo-cutaneo do reto-abdominal livre. Este trabalho descreve as indicacoes, taticas, resultados e complicacoes, especificamente desta tecnica em nosso meio.