Manejo de defeitos complexos do couro cabeludo após excisão de tumores malignos / Management of complex scalp defects after excision of malignant tumors

Introdução: A reconstrução do couro cabeludo após a ressecção oncológica continua sendo um desafio para o cirurgião, especialmente considerando a incidência crescente de câncer de pele entre pacientes idosos. A matriz dérmica (MD) é um grupo heterogêneo de materiais de cobertura de feridas que auxiliam no fechamento da ferida e substituem algumas das funções da pele, temporária ou permanentemente. Pacientes com maior risco cirúrgico podem se beneficiar do uso de MD, que ajuda a gerar uma nova derme, oferecendo grandes melhorias na cobertura de defeitos complexos e extensos. Métodos: É um trabalho retrospectivo com análise de prontuário e relato de dois casos de pacientes do A.C.Camargo Cancer Center-SP, Brasil. Resultados: Relatamos dois casos de defeitos complexos e extensos de couro cabeludo em um centro único usando MD associada a enxerto cutâneo e terapia de pressão negativa (TPN) na cirurgia reconstrutiva após ressecção de neoplasia maligna da pele com resultados funcionais e estético satisfatório. Conclusões: As lesões extensas do couro cabeludo são um desafio na prática clínica e um tratamento multidisciplinar é fundamental. Os resultados obtidos indicam que a MD associada com a enxertia de pele parcial e com a TPN tem enorme potencial para aumentar as opções terapêuticas disponíveis para o cirurgião e possivelmente beneficiando os pacientes, especialmente aqueles que não têm condições clínicas para uma cirurgia extensa de cobertura com retalho microcirúrgico.

Introduction: Scalp reconstruction after cancer resection remains a challenge for surgeons, especially considering the increasing incidence of skin cancer among elderly patients. Dermal matrix (DM) is a heterogeneous group of wound covering materials that aid in wound closure and replace some of the skins functions, either temporarily or permanently. Patients at higher surgical risk can benefit from the use of DM, which help to generate a new dermis, offering great improvements in coverage of complex and extensive defects Methods: It is a retrospective study with analysis of medical records and report of two cases of patients at the A.C.Camargo Cancer Center-SP, Brazil. Results: We report two cases of complex and extensive scalp defects at a single center using DM associated with skin grafting and negative pressure therapy (NPT) in reconstructive surgery after resection of malignant skin neoplasm with satisfactory functional and esthetic results. Conclusions: Extensive lesions of the scalp are a challenge in clinical practice and a multidisciplinary treatment is essential. The results obtained indicate that DM associated with partial skin grafting and NPT have enormous potential to increase the therapeutic options available to the surgeon and possibly benefit patients, especially those who do not have the clinical conditions for extensive coverage surgery with microsurgical flap.

Análise do uso de matriz de regeneração dérmica em crianças / Analysis of the use of dermal regeneration matrix in children

OBJETIVO: Analisar as utilizações e do desfecho imediato da MRD Integra® no fechamento cutâneo de lesões extensas em crianças atendidas no serviço de Cirurgia Pediátrica do Hospital Infantil Joana de Gusmão no período de janeiro de 2002 a dezembro de 2017. MÉTODO: Trata-se de um estudo retrospectivo, analítico e vertical que avaliou os arquivos de todas as crianças submetidas a aplicação de MRD no período de janeiro de 2002 a dezembro de 2017, totalizando 155 pacientes. RESULTADOS: Foram analisados 155 pacientes submetidos ao implante de MRD, totalizando 191 implantes. A maioria dos pacientes era do sexo masculino (58,06%) e pré-púberes (32,02%). Os diagnósticos mais prevalentes foram queimadura em fase aguda (35,97%), retração cicatricial (32,8%) e retração cicatricial e cicatriz hipertrófica (14,28%). A pega total do implante foi observada em 68,42% dos pacientes, numa média de 19,16 dias. O número de implantes submetidos ao tratamento conjunto com curativos de pressão negativa (CPN) foi de 86 (46,24%). A porcentagem média de pega parcial foi de 82,30%. Dos 191 implantes, 58 tiveram complicações (30,36%). CONCLUSÕES: As MRD são uma opção atual para cobertura cutânea em crianças, com utilizações diversas, taxa aceitável de complicações e bom resultado imediato.

OBJECTIVE: To analyze the uses and the immediate outcome of MRD Integra® in the cutaneous closure of extensive lesions in children seen at the Pediatric Surgery service of Hospital Infantil Joana de Gusmão from January 2002 to December 2017. METHODS: This is a retrospective, analytical and vertical study that evaluated the files of all children submitted to the application of MRD from January 2002 to December 2017, totaling 155 patients. RESULTS: 155 patients submitted to MRD implantation were analyzed, totaling 191 implants. Most patients were male (58.06%) and prepubertal (32.02%). The most prevalent diagnoses were acute burns (35.97%), scar retraction (32.8%) and scar retraction and hypertrophic scarring (14.28%). Total implant take-up was observed in 68.42% of patients, with an average of 19.16 days. The number of implants submitted to joint treatment with negative pressure dressings (CPN) was 86 (46.24%). The average percentage of partial catch was 82.30%. Of the 191 implants, 58 had complications (30.36%). CONCLUSIONS: MRDs are a current option for skin coverage in children, with different uses, an acceptable rate of complications and a good immediate result.

Efficacy of bilayer artificial dermis graft plus single layer dermal template for repair of lower extremity wounds with large area of exposed bone / 中华创伤杂志

Objective:To compare the efficacy of bilayer artificial dermis graft plus single layer dermal template and bilayer artificial dermis graft only in repairing lower extremity wounds with large area of exposed bone.Methods:A retrospective case-control study was conducted to analyze the clinical data of 34 patients with 37 wounds of the lower extremity involving large area of exposed bone admitted to Beijing Jishuitan Hospital from November 2009 to November 2020. There were 27 males and 7 females, aged 9-67 years [35.5(29, 45)years]. The exposed bone in the lower leg, ankle and foot was greater than 10 cm 2 in size (the shortest distance from edge to edge of bony exposure was more than 2 cm). At the first stage, the wounds were grafted with bilayer type artificial dermis only for 21 wounds of 20 patients in Group A, and grafted with bilayer type artificial dermis plus single layer dermal template for 16 wounds of 14 patients in Group B. At the second stage, the auto-skin graft was performed in the two groups. The wound healing rate was observed in all patients, and was compared between the two groups at 2 weeks and 2 months after the second stage operation. At the same time, the interval between first stage and second stage surgery was measured. The Vancouver Scar Scale (VSS) was used to evaluate the scar in the skin grafting area in the two groups at 5-6 months after the second stage operation. Results:All patients were followed up for 1 to 24 months [5(2, 7.5)months]. The total excellent and good wound healing rate in all patients was 81%(30/37) at 2 weeks and 97%(36/37) at 2 months. There was no significant difference between the Group A and Group B in the excellent and good wound healing rate at 2 weeks [(76%(16/21) vs. 88%(14/16)] and at 2 months [95%(20/21) vs. 100%(16/16)] ( P>0.05). In Group A, the bilayer artificial dermis was grafted into 4 wounds again to complete exposed bone coverage. However, all wounds in Group B were covered initially without re-grafting. The interval between the two-stage operation was 20(16, 21)days in Group A after the 4 patients who underwent secondary artificial dermal transplantation were excluded, showing no significant difference from 21(21, 23)days in Group B ( P>0.05). At 5-6 months after the second stage operation, the VSS score in Group B [(8.0±1.2)points] was significant less than that in Group A [(9.2±1.1)days] ( P<0.05). In the sub-index of VSS, the score of color and softness of scar in Group B [(2.0±0.6)points, (1.6±0.5)points] were significantly improved compared to those in Group A [(2.5±0.5)points, (2.2±0.7)points] ( P<0.05). Conclusions:The artificial dermis grafting is effective in treatment of lower extremity wounds with large area of exposed bone. However, the bilayer artificial dermis graft plus single layer dermal template can avoid artificial dermal re-graft in repair of large area of exposed bone, and the interval between two-stage operation is not significantly prolonged. Moerover, the color and texture of scar after skin grafting and wound repair efficiency and quality are improved.

The effect of artificial dermis combined with autogenous thin skin graft on the survival rate of compound skin grafts and the scar state of joints in burned patients / 中国医师杂志

Objective:To explore the effect of artificial dermis combined with autogenous thin skin graft on the survival rate of compound skin graft and the scar state of joints in burn patients.Methods:94 burned patients treated in Baoding Fifth Hospital from August 2017 to August 2019 were prospectively selected as the research objects. They were randomly divided into two groups with 47 cases in each group. The control group was treated with simple medium thick skin transplantation, and the observation group was treated with artificial dermis combined with autologous thin skin grafting. The recovery of the two groups (healing time of skin donor area, healing time of skin graft area, healing time under scab of burn area and hospitalization time) were compared. The survival rate of composite skin transplantation, wound healing, Vancouver Scar Scale (VSS) score, joint range of motion (shoulder abduction, knee flexion, knee extension), Burn Specific Health Scale-Brief (BSHS-B), Profile of Mood States-Short Form (POMS-SF) score and complications were compared.Results:The healing time of donor area, skin graft area, subeschar healing time and hospital stay in the observation group were shorter than those in the control group ( P<0.05). The wound healing in the observation group was better than that in the control group, and the survival rate of composite skin transplantation was higher than that in the control group ( P<0.05). After treatment, the scar state of the joint in the two groups was improved compared with that before treatment ( P<0.05); The scar thickness, vascular distribution score and total score of VSS in the observation group were lower than those in the control group ( P<0.05). After treatment, the joint range of motion in the two groups was improved compared with that before treatment ( P<0.05); The shoulder abduction, knee flexion and knee extension in the observation group were higher than those in the control group ( P<0.05). After treatment, the quality of life and psychological status of the two groups were improved compared with those before treatment ( P<0.05); The BSHS-B score of the observation group was higher than that of the control group, and the POMS-SF score was lower than that of the control group ( P<0.05); The incidence of complications in the observation group (4.26%) was lower than that in the control group (21.28%) ( P<0.05). Conclusions:Artificial dermis combined with autologous thin skin graft can significantly improve the survival rate of compound skin graft in burned patients, and can further reduce the scar condition of the joints of patients, reduce the incidence of complications, and effectively improve the prognosis of patients.

National expert consensus on the application of natural dermal matrix in wound repair (2020 version) / 中华烧伤杂志

Natural dermal matrix has good biocompatibility and can serve as " biological template" in wound repair. According to the source of material, natural dermal matrix can be divided into acellular dermal matrix (ADM), denatured dermal matrix, and scar dermal matrix. ADM is a biological material prepared by removing cellular components from the skin and retaining extracellular matrix (ECM) of the dermis. ADM possesses abundant natural biological information, low immunogenicity, and excellent regenerative capacity, which has greatly promoted the development of wound healing specialty as dermal substitute. Denatured dermis matrix is a layer of dermal tissue made by superficial tangential excision or dermabrasion on deeply burned wounds. The retained denatured dermis can recover gradually after transplantation of autologous skin on its surface, with similar structure, morphology, and biomechanics to healthy dermis. Scar dermal matrix is a kind of dermal scaffold made of autologous split-thickness scar tissue, possessing the characteristics of high survival rate, good texture, and slight scar reaction. Scar dermal matrix can effectively reduce secondary damage to the donor site when repairing scar contracture deformity. Based on the research progress at home and abroad and the opinions of domestic experts, this paper summarizes the indications, application methods, contraindications, and considerations of different types of natural dermal matrix in application of wound repair.

Tratamento pediátrico de grande queimado agudo: Manejo clínico, cirúrgico e uso de matriz de regeneração dérmica / Pediatric treatment of large acute burn: Clinical, surgical management and use of dermal regeneration matrix / Tratamiento pediátrico de gran quemado agudo: Manejo clínico, quirúrgico y uso de matriz de regeneración dérmica

Objetivo: Analisar o tratamento de queimaduras em fase aguda, conduta clínica, cirúrgica e uso de matriz de regeneração dérmica (MRD) em criança internada na Unidade de Queimados do Hospital Regional da Asa Norte (UQ-HRAN), Brasília-DF. Relato do Caso: D.M.R., 2 anos e 7 meses, masculino, vítima de queimadura por chama direta, 60% de superfície corporal acometida, 50% sendo de espessura total. Atendido inicialmente segundo Protocolo de Rotinas da UQ-HRAN, entretanto, evoluiu com piora clínica, necessitando de Unidade de Terapia Intensiva pediátrica, por 58 dias. Neste período, foi submetido a 2 escarotomias, 3 desbridamentos e 10 hemotransfusões, apresentou infecções nas áreas queimadas e variados esquemas antibióticos. Tendo em vista a extensão de áreas acometidas, restrição de áreas doadoras viáveis e impossibilidade de outros curativos, optou-se pelo implante de MRD no 16° dia de internação e, após a integração, foram realizadas 6 enxertias cutâneas. Recebeu alta no 118° dia de internação. Conclusão: Houve necessidade de assistência clínica e cuidados intensivos, além de utilização de técnica cirúrgica com implante de MRD em grande queimado agudo. Sendo assim, a MRD teve como objetivo proporcionar leito receptor de qualidade, associado a maior integração para enxertia cutânea futura, pois a carência de áreas doadoras o colocaria em risco de vida maior. Esse conjunto de fatores contribuiu para o sucesso do tratamento e a boa recuperação da criança.

Objective: To analyze the treatment of burn in acute-phase using clinical, surgical management and use of dermal regeneration matrix (DRM) in a child hospitalized at the Burn Unit of Asa Norte Regional Hospital (BU-ANRH), Brasília-DF. Case Report: D.M.R., 2 years and 7 months old, male, victim of direct fire, 60% of body surface affected, 50% full-thickness. Initially treated according to the BU-ANRH Routine Protocol, however, evolved to clinical decline, requiring a pediatric Intensive Care Therapy for 58 days. During this period, he underwent two escharotomies, three debridements and 10 blood transfusions. He exhibited infection in burned areas and used multiple antibiotic schemes. Due to the extension of affected surface, restriction of viable donor zone and unusable of other bandages, DRM was implanted on the 16th day of hospitalization and integration, he has done six cutaneous grafting. He was discharged on the 118th day of hospitalization. Conclusion: Clinical and intensive care were needed, besides the use of surgical technique with DRM implantation in a large acute burn. Thus, DRM has had as a goal to provide quality receptor bed, associated with greater integration for future cutaneous grafting, since the lack of donor areas would put it at greater risk of life. This set of factors contributed to the success of the treatment and the good recovery of the child.

Objetivo: Analizar el tratamiento de quemaduras en fase aguda, conducta médica clínica, quirúrgica y uso de matriz de regeneración dérmica (MRD) en niño internado en la Unidad de Quemados del Hospital Regional de Asa Norte (UQ-HRAN), Brasília-DF. Reporte de Caso: D.M.R., 2 años y 7 meses, masculino, víctima de quemadura de llama directa, 60% de la superficie del cuerpo afectada, 50% del espesor total. Inicialmente tratado de acuerdo con el Protocolo de Rutina UQ-HRAN, sin embargo, evolucionó con un empeoramiento clínico, necesitando cuidados en la Unidad de Terapia Intensiva pediátrica durante 58 días. Durante este período, fue sometido a 2 escarotomías, 3 desbridamientos y 10 transfusiones de sangre. Presentó infecciones en zonas quemadas y variados esquemas antibióticos. Debido a la extensión de las áreas afectadas, la restricción de las áreas viables de los donantes y la imposibilidad de otros curativos, se optó por el implante de MRD en el 16° día de internación y después de la integración, se realizaron 6 injertos cutáneos. Recibió alta en el 118° día de internación. Conclusión: Hubo necesidad de asistencia clínica y cuidados intensivos, además de utilización de técnica quirúrgica con implante de MRD en gran quemado agudo. Por lo tanto, la MRD tuvo como objetivo proporcionar lecho receptor de calidad, asociado a la mayor integración para el injerto cutáneo futuro, pues la carencia de áreas donantes lo pondría en mayor riesgo de vida. Este conjunto de factores, contribuyó al éxito del tratamiento y la buena recuperación del niño.

Experts consensus on clinical application of bilayer artificial dermis (2019 version) / 中华烧伤杂志

Artificial dermis is a kind of tissue engineering dermal substitute and is used to repair dermal defects caused by a variety of reasons. This article describes the characteristics and the mechanism of repair and reconstruction of bilayer artificial dermis. Based on domestic experience of clinical applications and relative literature of bilayer artificial dermis, more than 50 domestic experts in related field reached a consensus on indications, contraindications, operation procedures in clinical application, cautions, and treatment and prevention of complications of bilayer artificial dermis, providing reference for clinical application.

Analysis of clinical effects of artificial dermis in functional reconstruction in the late stage of extremely severe burn / 中华烧伤杂志

Objective@#To explore the clinical effects of artificial dermis combined with autologous split-thickness skin transplantation in the treatment of functional reconstruction in the late stage of extremely severe burn.@*Methods@#From May 2015 to May 2017, medical records of 40 patients with limited activity after scar hyperplasia and conforming to the study criteria, injured in August 2nd Kunshan factory aluminum dust explosion accident in 2014, and had surgeries in our hospital and rehabilitation treatment in our hospital′s alliance rehabilitation hospital, Rehabilitation Hospital of Kunshan Zhou City, were retrospectively analyzed. According to the treatment methods, 20 patients (12 males and 8 females, aged 20 to 45 years) were enrolled in artificial dermis group. They were conducted with stage Ⅰ functional site scar loosening and artificial dermis (PELNAC) implanting+ stage Ⅱ transplantation of autologous split-thickness skin. Another 20 patients (14 males and 6 females, aged 20 to 45 years) were enrolled in conventional skin grafting group. They were conducted with stage Ⅰ functional site scar loosening and transplantation of autologous thin medium-thickness skin. After 5 days of autologous skin transplantation, the survival rates of autologous skin in patients of 2 groups were calculated. The autologous skin infection and complete healing time of skin grafting area in patients of 2 groups were recorded. In 3, 6, and 10 months after autologous skin transplantation, the Vancouver Scar Scale (VSS) was used to assess the scar condition of recipient site in patients of 2 groups. The complete healing time of donor site in patients of 2 groups was recorded. In 10 months after autologous skin transplantation, VSS was used to assess the scar condition of donor site in patients of 2 groups. In 12 months after autologous skin transplantation, the functional recovery of surgical function reconstruction site in patients of 2 groups was evaluated and rated. Data were processed with t test, analysis of variance for repeated measurement, Wilcoxon rank-sum test, chi-square test, Fisher′s exact probability test, and Bonferroni correction.@*Results@#(1) After 5 days of autologous skin transplantation, the survival rate of autologous skin in patients of artificial dermis group was (95±3)%, similar to (93±3)% in conventional skin grafting group (t=1.262, P>0.05). The results of autologous skin infection of patients in the 2 groups were similar (P>0.05). (2) After autologous skin grafting, the complete healing time of skin grafting area in patients of artificial dermis group was (12.3±2.5) d, similar to (12.7±2.0) d of conventional skin grafting group (t=-0.139, P>0.05). In 3, 6, and 10 months after autologous skin transplantation, the VSS scores of scars in recipient site of patients in artificial dermis group were significantly lower than those of conventional skin grafting group (t=-4.428, -5.655, -6.839, P<0.01). (3) After autologous skin grafting, the complete healing time of donor site in patients of artificial dermis group was obviously shorter than that in conventional skin grafting group (t=-12.435, P<0.01). In 10 months after autologous skin transplantation, the VSS score in donor site of patients in artificial dermis group was significantly lower than that of conventional skin grafting group (t=-16.971, P<0.01). (4) After 12 months of autologous skin transplantation, the functional improvement levels of the functional site of patients in artificial dermis group were good in 4 patients, fair in 15 patients, and bad in 1 patient, while the functional improvement levels of the functional site of patients in conventional skin grafting group were good in 5 patients, fair in 8 patients, and bad in 7 patients. The functional improvement levels of the functional site of patients between the two groups were similar (Z=371.5, P>0.05).@*Conclusions@#Compared with conventional stage Ⅰ functional site scar loosening and transplantation of autologous thin medium-thickness skin, stage Ⅰ functional site scar loosening and artificial dermis implanting+ stage Ⅱ transplantation of autologous split-thickness skin does not affect the survival of skin in the early stage and can effectively improve functional site function, reduce VSS scores of donor site and recipient site, and shorten complete healing time of donor site.

Experts consensus on clinical application of bilayer artificial dermis (2019 version) / 中华烧伤杂志

Artificial dermis is a kind of tissue engineering dermal substitute and is used to repair dermal defects caused by a variety of reasons. This article describes the characteristics and the mechanism of repair and reconstruction of bilayer artificial dermis. Based on domestic experience of clinical applications and relative literature of bilayer artificial dermis, more than 50 domestic experts in related field reached a consensus on indications, contraindications, operation procedures in clinical application, cautions, and treatment and prevention of complications of bilayer artificial dermis, providing reference for clinical application.

Preparation of bioactive denatured acellular dermal matrix from burn mice riched in mice bone marrow mesenchymal stem cells / 中华烧伤杂志

Objective@#To investigate the preparation of bioactive denatured acellular dermal matrix (DADM) from burn mice riched in mice bone marrow mesenchymal stem cells.@*Methods@#Twelve BALB/c mice were collected and 20% total body surface area scalds (hereinafter referred to as burns) with deep partial thickness were inflicted on the back skin of each mouse. After removing epidermis, the burned skin were collected and divided into Triton X-100 group and elhylene diamine tetraacetic acid (EDTA) group according to the random number table, with 15 samples in each group. Samples in Triton X-100 group and EDTA group were respectively placed in mixture of 2.5 g/L Triton X-100 and 2.5 g/L trypsin solution and mixture of 0.2 g/L EDTA and 2.5 g/L trypsin solution for sustained vibration and elution for 24 hours to make mice DADM. The general appearance of DADM was observed. The structure and arrangement of collagen fibers of DADM were observed by scanning electron microscope and tissue structure of DADM were observed by fluorescence microscope. Bone marrow mesenchymal stem cells (BMSCs) from mice were transplanted in mice DADM in the two groups with concentration of 2×105 cells per well to prepare bioactive mice DADM. After cultured for 3 days, tissue structure of bioactive mice DADM was observed by hematoxylin and eosin staining, distribution and number of BMSCs of bioactive mice DADM were observed by immunofluorescence staining. Proliferation of BMSCs of bioactive mice DADM after cultured for 2 h, 1 d, 3 d, and 5 d was detected by cell count kit-8. Data were processed with analysis of variance for repeated measurement and t test.@*Results@#(1) Mice DADM in the two groups were white in appearance with certain tenacity and elasticity. Mice DADM in the two groups maintained good three-dimensional porous network structure. Collagen fibers of mice DADM in EDTA group were with good continuity, and collagen fibers of mice DADM in Triton X-100 group were fractured in varying degrees. Mice DADM in the two groups were decellularized completely, and the collagen fibers were loose and arranged disorderly. The continuity of tissue structure of mice DADM in EDTA group was better than that of mice DADM in Triton X-100 group. (2) After cultured for 3 days, the BMSCs in bioactive mice DADM in the two groups were evenly distributed. The number of bioactive BMSCs in mice DADM in EDTA group was 37±7, which was significantly more than that of mice DADM in Triton X-100 group (25±8, t=0.128, P<0.05). The proliferation of bioactive BMSCs in mice DADM in Triton X-100 group and EDTA group was similar at 2 hours and on day 1 after cultured (t=1.292, 0.656, P>0.05). On 3, 5 days after cultured, the proliferation of bioactive BMSCs in mice DADM in EDTA group was significantly higher than that of mice DADM in Triton X-100 group (t=2.309, 14.128, P<0.05 or P<0.01).@*Conclusions@#Mice DADM prepared by decellularization of EDTA has better three-dimensional porous network structure and good continuity of collagen fiber. The BMSCs in bioactive DADM from burn mice prepared by transplanting BMSCs are evenly distributed with large quantity and strong proliferative capacity, which has the potential to be good autologous dermal substitute.

Antiseptic effect of compound lysostaphin disinfectant and its preventive effect on infection of artificial dermis after graft on full-thickness skin defect wound in rats / 中华烧伤杂志

Objective@#To study the antiseptic effect of compound lysostaphin disinfectant and its preventive effect on infection of artificial dermis after graft on full-thickness skin defect wound in rats.@*Methods@#(1) Each one standard strain of Klebsiella pneumoniae, Acinetobacter baumannii, and Staphylococcus aureus were selected. Each 20 clinical strains of Klebsiella pneumoniae, Acinetobacter baumannii, and Staphylococcus aureus were collected from those isolated from wound exudates of burn patients hospitalized in our wards from January 2014 to December 2016 according to the random number table. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of compound lysostaphin disinfectant to above-mentioned strains were detected. The experiment was repeated 3 times. Compared with the corresponding standard strain, the clinical strain with higher MIC and/or MBC was considered as having decreased sensitivity to the disinfectant. The percentage of strains of each of the three kinds of bacteria with decreased sensitivity was calculated. (2) Artificial dermis pieces were soaked in compound lysostaphin disinfectant for 5 min, 1 h, 2 h, and 4 h, respectively, with 21 pieces at each time point. After standing for 0 (immediately), 12, 24, 36, 48, 60, 72 h (with 3 pieces at each time point), respectively, the diameters of their inhibition zones to standard strains of Klebsiella pneumoniae, Acinetobacter baumannii, and Staphylococcus aureus were measured. The experiment was repeated 3 times. The shortest soaking time corresponding to the longest standing time, after which the disinfectant-soaked artificial dermis could form an effective inhibition zone (with diameter more than 7 mm), was the sufficient soaking time of the disinfectant to the artificial dermis. (3) Forty Sprague-Dawley rats were divided into post injury day (PID) 3, 7, 14, and 21 sampling groups according to the random number table, with 10 rats in each group. A full-thickness skin defect wound with a diameter of 20 mm was made on both sides of the spine on the back of each rat. Immediately after injury, the artificial dermis without any treatment was grafted on the wound on left side of the spine (hereinafter referred to as control wound), while the sufficiently soaked artificial dermis with compound lysostaphin disinfectant was grafted on the wound on right side of the spine (hereinafter referred to as disinfectant wound). On PID 3, 7, 14, and 21, the gross condition of wounds of all the surviving rats was observed, and the new infection rates of control wounds and disinfectant wounds were calculated. Then, the rats in the sampling group with corresponding time were killed, and the full-thickness wound tissue containing artificial dermis was collected for quantitative analysis of bacteria. Bacteria content of the uninfected control wounds and that of the uninfected disinfectant wounds were compared. Data were processed with chi-square test and Wilcoxon rank sum test.@*Results@#(1) The MIC of compound lysostaphin disinfectant to standard strains of Staphylococcus aureus, Klebsiella pneumoniae, and Acinetobacter baumannii were 1/32, 1/32, and 1/512 of the original concentration of the disinfectant, respectively, and the MBC were 1/32, 1/16, and 1/512 of the original concentration of the disinfectant, respectively. The percentages of clinical strains of Klebsiella pneumoniae, Acinetobacter baumannii and Staphylococcus aureus with decreased sensitivity to compound lysostaphin disinfectant were 15% (3/20), 20% (4/20), and 10% (2/20), respectively. (2) After being soaked in compound lysostaphin disinfectant for 2 and 4 h, the longest standing time, after which the artificial dermis could form an effective inhibition zone against Klebsiella pneumoniae, Acinetobacter baumannii, and Staphylococcus aureus, were 24, 36, and 48 h respectively, longer than 12, 24, and 24 h of soaking for 5 min and 24, 24, and 36 h of soaking for 1 h. The sufficient soaking time of compound lysostaphin disinfectant to artificial dermis was 2 h. (3) On PID 3, no infection symptom was observed in all the wounds, and so both the new infection rate of control wounds and that of disinfectant wounds were 0. The artificial dermis was transparent but not well connected with the wound. On PID 7, the new infection rate of control wounds was 20.00% (6/30), which was obviously higher than 3.33% (1/30) of disinfectant wounds, χ2=4.043, P<0.05. On the infected wound, a large amount of purulent exudates were observed, and the artificial dermis was not connected with the wound and degraded partially. On the uninfected wound, artificial dermis was transparent and had a partial connection with the wound. On PID 14 and 21, no new infected wound was observed, and so both the new infection rate of control wounds and that of disinfectant wounds were 0. There was no obvious improvement on the infected wounds. The collagen layers of artificial dermis in the uninfected wound established a good connection with the wound and were separating from the silica gel layer gradually. Infection occurred in 2, 3, 1 control wound (s) in PID 7, 14, and 21 sampling groups, respectively, and in 1 disinfectant wound in PID 14 sampling group. The bacteria content of the infected wounds tissue was 0.79×106 to 7.22×109 colony-forming unit (CFU)/g. The bacteria content of uninfected control wounds tissue in PID 3, 7, and 14 sampling groups were (3.43±1.88)×102, (2.37±0.43)×103, and (8.40±1.03)×103 CFU/g, respectively, which were significantly higher than (0.33±0.12)×102, (0.43±0.17)×103, (2.16±0.52)×103 CFU/g of uninfected disinfectant wounds tissue (Z=-3.780, -3.554, -3.334, P<0.05). The bacteria content of uninfected control wounds tissue and that of uninfected disinfectant wounds tissue in PID 21 sampling group were similar (Z=-0.490, P>0.05).@*Conclusions@#Compound lysostaphin disinfectant has quite strong antibacterial ability against Klebsiella pneumoniae, Acinetobacter baumannii, and Staphylococcus aureus. Clinical strains of the three kinds of bacteria were highly sensitive to compound lysostaphin disinfectant. Saturation of absorption of compound lysostaphin disinfectant achieves in artificial dermis after 2 hours′ soaking. After 24, 36, and 48 hours′ standing, the soaked artificial dermis still has the antibacterial effect on Klebsiella pneumoniae, Acinetobacter baumannii, and Staphylococcus aureus, respectively. The infection rate and the bacteria content of full-thickness skin defect wound in rats are all decreased when grafted with soaked artificial dermis.

Construction and characterization of a full-thickness skin model with collagen matrix / 中华皮肤科杂志

Objective To construct a collagen matrix-based skin model that can last a long time in vitro for potential application of subsequent tests and studies.Methods The porcine collagen and normal human skin fibroblasts were mixed and seeded into the culture dish,which were cultured for 3-4 days to obtain a dermal structure.Then,the third-to seventh-passage normal human keratinocytes were seeded onto the dermal surface and cultured for 14 days to obtain a double-layer skin model.Hematoxylin and eosin (HE)staining and Masson staining were performed to evaluate the morphology and structure of the skin model,and electron microscopy was conducted to observe the ultrastructure of the skin model.Immunohistochemical study and immunofluorescence staining were conducted to determine the expression of major markers in each layer of the skin model.Results HE and Masson staining showed that the skin model and normal human skin tissues showed very similar dermal and epidermal structures.After harvest of the skin model,it can be cultured in vitro for another 14 days with favorable and stable dermal and epidermal structures.Electron microscopy showed lipids in the stratum corneum,keratohyalin granules in the stratum granulosum,corneodesmosomes,desmosomes and basal membrane in the skin model.Immunohistochemical and immunofluorescence staining showed the consistent expression of transglutaminase,filaggrin,keratin 10 and Ki67 in the epidermis in both the skin model and normal skin.Moreover,the expression of type Ⅳ collagen and laminin-5 in the basal membrane,as well as that of type Ⅰ collagen,type Ⅲ collagen and fibrillin in the dermis were both consistent between the skin model and normal skin.Conclusion The constructed three-dimensional (3D) skin model is highly analogous to normal human skin in the aspect of tissue structure and various protein expression,and the skin model can be stably cultured in vitro for at least 14 days after harvest.

Construction of living skin equivalents using mixed autologous and allogeneic skin cells for repairing scar contracture of the hand in a patient with recessive dystrophic epidermolysis bullosa / 中华皮肤科杂志

Objective To evaluate the effect of living skin equivalents (LSE) constructed of mixed autologous and allogeneic skin cells and human amnion which served as a matrix on repairing scar contracture of the hand in a patient with recessive dystrophic epidermolysis bullosa (RDEB).Methods Skin tissues were obtained from a patient with RDEB and her mother,and epidermal keratinocytes and dermal fibroblasts were isolated from these tissues and cultured in vitro separately.Human amnion was obtained from the placenta of an unrelated healthy parturient undergoing cesarean delivery,and served as a matrix of the LSE.The autologous and allogeneic fibroblasts were mixed and seeded on the stromal side of the amnion,and then the autologous and allogeneic keratinocytes were mixed and seeded on the epithelial side of the amnion,so as to construct the human amnion-LSE (AM-LSE).Histological examination was performed to observe the structure of the skin tissues obtained from the patient and her mother,and immunofluorescence staining was conducted to detect the expression of type Ⅶ collagen in the skin tissues of the patient and her mother and in the AM-LSE.The AM-LSE was grafted on the skin defects of the patient after release of scar contracture of the hand.After grafting,the survival status of the AM-LSE graft and repairing effect on the wounds were evaluated.Results The constructed AM-LSE consisted of dermis,multilayered and fully differentiated epidermis and well-developed basement membrane.Immunofluorescence examination revealed that type Ⅶ collagen was linearly distributed along the basement membrane.Half a year after grafting,the AM-LSE survived well,and no obvious rejection reaction was observed.No blisters or ulcers occurred at the recipient sites,and the scar contracture was mild.The grafted area showed normal skin color with soft texture.The patient could grab and hold things,which had met self-care requirements of daily living.Conclusions The AM-LSE constructed of mixed autologous and allogeneic skin cells have good histological structures,and can be grafted on the wounds after resection of the scars in a RDEB patient.After grafting,no obvious rejection reaction was observed,and the skin was not liable to develop blisters,ulcers or scar contracture due to friction.

Research progress in skin substitute for large area burned patients / 中国医师杂志

The most important thing for the treatment of large area burned patients is to effectively cover the wound in time to prevent the occurrence and development of wound sepsis.Therefore,searching for the effective wound closure approach is the hot spot of research of large area burn treatment in recent years.There are more and more kinds of skin substitutes along with the progress of material science and technology.In this paper,we review the research on skin substitutes of large area burn treatment in China and abroad.

Uso da matriz de regeneração dérmica em retração cicatricial por queimadura: Relato de caso / The use of template dermal regeneration in burn scar contraction: Case report

OBJETIVO: A ausência de áreas doadoras suficientes ou apresentando má qualidade para o tratamento de retração cicatricial após queimaduras determina muitas vezes resultados insatisfatórios. Nesse contexto, surgiram as matrizes de regeneração dérmica - e entre elas encontra-se o Integra®. Este estudo discute as aplicações desse substituto dérmico à luz de um caso de retraçao cicatricial significativa. MÉTODO: Relato de caso. Paciente feminino, 43 anos, sofreu na infância queimadura da região cervical, tronco e membros superiores com querosene. Apresentou retração cicatricial grave, procurando auxílio médico 29 anos após o acidente. Foi submetida à ressecção da contratura cicatricial, sendo utilizada matriz de regeneração dérmica e posterior enxertia de pele parcial autóloga. RESULTADOS: Não houve complicações após os dois procedimentos cirúrgicos. O tempo de internação foi de 30 dias. O seguimento de 48 meses. Retração cicatricial recorrente foi observada, porém menor que a apresentada previamente pela paciente e sem prejuízo funcional. CONCLUSOES: O uso da matriz dérmica é uma excelente opção para o tratamento da retração cicatricial. A indicação clássica do seu uso é em uma área de cicatriz, com ou sem contratura, abrangendo qualquer local do corpo onde as técnicas de expansão e/ou retalho tecidual não podem resolver o problema, seja por causa da localização, escassez de pele saudável, ou tamanho da lesão.

OBJECTIVE: The absence of sufficient donor areas or having poor quality for the treatment of scar retraction after burns often determine unsatisfactory results. In this context emerged the matrix of dermal regeneration - and between them lies the Integra®. This study discusses the applications of dermal substitute in the light of a case of significant scar retraction. METHOD: Case report. Female patient, 43, suffered burns in childhood neck, trunk and upper limbs with kerosene. Had severe scar retraction, seeking medical attention 29 years after the accident. It underwent resection of scar contracture, being used dermal regeneration matrix and subsequent grafting autologous partial skin. RESULTS: There were no complications after the two surgical procedures. The length of stay was 30 days. The follow-up of 48 months. Recurring scar retraction was observed, but less than previously presented by the patient and without functional impairment. CONCLUSIONS: The use of the dermal matrix is an excellent option for the treatment of scar retraction. The classic indication of use is in a scarred area, with or without contracture, covering anywhere on the body where the expansion of technical and/or tissue flap can not solve the problem either because of the location, healthy skin shortage, or lesion size.

New biological dermis cover Pelnac? in wound healing of children with severe trauma / 中国组织工程研究

BACKGROUND:In recent years, tissue engineering has made great progress, and skin tissue engineering is especialy noteworthy. Artificial dermis (PELNAC) is relatively used widely, but there is a lack of relevant reports on wound repair in children. OBJECTIVE:To investigate the clinical efficacy of Pelnac? METHODS:In a retrospective study, 22 patients with the wound of severe trauma were treated with Pelnac as skin graft dressings on treatment of the wounds of severe trauma in children. ? graft, negative-pressure wound therapy and split-thickness skin graft as experimental group (Pelnac? group), and another 19 patients treated with granulation formation dressing and split-thickness skin graft as control group. We colected data including the graft livability, the required re-operative times and the epithelization time after the skin graft. During the folow-up, the skin color and texture of survival skin, subcutaneous fulness, scar hyperplasia and the joint function were also evaluated. RESULTS AND CONCLUSION: In the Pelnac ? group, the graft livability was up to 90% within 10-14 days after grafting. The secondary split-thickness skin graft was required in two cases in the Pelnac? group and in eight cases in the control group. There was a significant difference in the graft livability (P < 0.05). The average epithelization time after the skin graft was (13.86±3.09) days in the Pelnac? group, which was significant shorter than the control group, (19.10±4.62) days, after the first time operation (P< 0.05). During the 10 months folow-up, the survival skin color and skin elasticity in the Pelnac? group was significantly better than that in the control group (P< 0.05). Better subcutaneous fulness and milder scar hyperplasy in the injured sites were obtained in the Pelnac? group compared with the control gorup. Five cases had certain joint function limitation in the Pelnac? group, compared to 10 cases in the control group, with a significant difference (P < 0.05). Artificial dermis Pelnac? has a stronger anti-infectious ability and higher graft livability. Pelnac? graft combined with negative-pressure wound therapy, granulation culture and split-thickness skin graft can shorten the epithelization time, improve wound healing and aleviate harm to the joint function after the skin graft.

The Use of Matriderm and Autologous Skin Graft in the Treatment of Full Thickness Skin Defects

BACKGROUND: For patients with full thickness skin defects, autologous Split-thickness skin grafts (STSG) are generally regarded as the mainstay of treatment. However, skin grafts have some limitations, including undesirable outcomes resulting from scars, poor elasticity, and limitations in joint movement due to contractures. In this study, we present outcomes of Matriderm grafts used for various skin tissue defects whether it improves on these drawbacks. METHODS: From January 2010 to March 2012, a retrospective review of patients who had undergone autologous STSG with Matriderm was performed. We assessed graft survival to evaluate the effectiveness of Matriderm. We also evaluated skin quality using a Cutometer, Corneometer, Tewameter, or Mexameter, approximately 12 months after surgery. RESULTS: A total of 31 patients underwent STSG with Matriderm during the study period. The success rate of skin grafting was 96.7%. The elasticity value of the portion on which Matriderm was applied was 0.765 (range, 0.635-0.800), the value of the trans-epidermal water loss (TEWL) was 10.0 (range, 8.15-11.00) g/hr/m2, and the humidification value was 24.0 (range, 15.5-30.0). The levels of erythema and melanin were 352.0 arbitrary unit (AU) (range, 299.25-402.75 AU) and 211.0 AU (range, 158.25-297.00 AU), respectively. When comparing the values of elasticity and TEWL of the skin treated with Matriderm to the values of the surrounding skin, there was no statistically significant difference between the groups. CONCLUSIONS: The results of this study demonstrate that a dermal substitute (Matriderm) with STSG was adopted stably and with minimal complications. Furthermore, comparing Matriderm grafted skin to normal skin using Cutometer, Matriderm proved valuable in restoring skin elasticity and the skin barrier.

Tissue-engineered skin construction with amniotic epithelial cells and amniotic mesenchymal stem cells / 中国组织工程研究

BACKGROUND: Placenta mesenchymal stem cells have become hot spots in stem cells study in recent years because of its advantages. OBJECTIVE:To analyze the biological characteristics of amniotic mesenchymal stem cells and amnion epithelial cells, and to explore the feasibility of amniotic mesenchymal stem cells and amnion epithelial cells applied as seed cells in three-dimensional liquid culture to construct the tissue-engineered skin. METHODS:The amniotic mesenchymal stem cells and amnion epithelial cells were obtained by using multi-step digestion with trypsin and col agenase;then the flow cytometry, reverse transcription-PCR and immunofluorescent staining techniques were adopted to identify the surface molecular markers, stem cellcharacteristics and keratinocytes similarity respectively. Based on these data, amniotic mesenchymal stem cells and amnion epithelial cells used as seed cells together with rat type Ⅰ col agen matrix were adopted for three-dimensional liquid culture. RESULTS AND CONCLUSION:Flow cytometry test showed that amniotic mesenchymal stem cells and amnion epithelial cells cultured in vitro could highly express CD90, CD73 and CD105, and could not express the hemopoietic stem cellmarker of CD34 and MHC-class Ⅱ molecular HLA-DR. Reverse transcription-PCR results detected that amniotic mesenchymal stem cells could express stem cellcharacteristic genes CMCY and NANOG;amnion epithelial cells could express stem cellcharacteristic genes CMCY and KLF4, showing that both amniotic mesenchymal stem cells and amnion epithelial cells have stem cellproperties. Reverse transcription-PCR results showed that amniotic mesenchymal stem cells could express keratinocytes characteristic genes K19,β1-integrin and K8;amnion epithelial cells could express K19,β1-integrin, K5 and K8. Immunofluorescence staining results showed amnion epithelial cells could express keratinocytes proliferation related protein K14, which revealed that there was certain similarity in the mRNA expression between keratinocytes and amnion epithelial cells, and indicating that it has the potential to differentiate into keratinocytes. Tissue-engineered skin was successful y constructed by using amniotic mesenchymal stem cells and amnion epithelial cells, hematoxylin-eosin staining section showed that it has certain skin structure, and amnion epithelial cells had a preliminary differentiation. Al these prove that it is feasible to construct human skin tissues with amniotic mesenchymal stem cells and amniotic epithelial cells through the three-dimensional culture.

Substitutos cutâneos: conceitos atuais e proposta de classificação / Skin substitutes: current concepts and a new classification system

Feridas complexas podem resultar na perda completa do revestimento cutâneo. A solução consagrada pela cirurgia plástica é a enxertia de pele autógena, porém há casos em que ocorre escassez de área doadora cutânea, um problema ainda não totalmente solucionado. Assim, atualmente há muito interesse por materiais sintéticos ou biológicos que possam ser utilizados como substitutos cutâneos. O objetivo deste estudo foi introduzir uma forma mais didática de agrupar diferentes tipos de substitutos cutâneos. Acreditamos que esses produtos podem ser classificados de forma mais abrangente se forem divididos segundo três critérios: camada substituída da pele, subdivididos em epidérmicos (E), dérmicos (D) e compostos dermoepidérmicos (C); duração no leito da ferida, subdivididos em temporários (T) e permanentes (P); e origem do material constituinte, subdivididos em biológicos (b), biossintéticos (bs) e sintéticos (s).

Complex wounds are characterized by complete loss of cutaneous cover. The most common plastic surgery technique is the autogenous skin graft; however, the amount of material available from donor areas is often limited. The development of synthetic or biological products as skin substitutes is therefore an area of interest. The present study aimed to classify the different types of skin substitutes available based on three criteria: the skin layer to be replaced, which can be categorized into epidermal (E), dermal (D), and dermal-epidermal composites (C); the durability in the wound bed, which can be temporary (T) or permanent (P); and the origin of the material, subdivided into biological (b), biosynthetic (bs), and synthetic (s).

In vitro construction of an artificial skin model of melanoma with human keratinocytes and human MV3 melanoma cells / 中华皮肤科杂志

Objective To construct an artificial skin model of melanoma by mixed culture of human keratinocytes and MV3 melanoma cells on de-epidermized dermis (DED) in order to study the effect of keratinocytes on melanoma invasion. Methods Epidermal cell suspension was obtained by a two-step digestion method from the circumcised foreskin of a child, keratinocyte serum-free medium was applied to the culture and passage of keratinocytes. MV3 melanoma cells were cultured and passaged in RPMI 1640 medium. Log-phase keratinocytes and MV3 cells were mixed with a ratio of 3:1 and seeded onto the surface of DED followed by a liquid culture and air-liquid culture for a total of 2 weeks. Thereafter, the artificial tissue model was assessed by HE staining and immunohistochemical staining for S-100 protein, HM64S and keratin. Results HE staining showed that MV3 cells formed band-like tumor masses or foci on the surface of DED, with keratinocytes intermingling among the tumor cells, but no typical epidermis-like structure was observed. Some tumor cells infiltrated into the surface of DED and showed a cluster distribution; some tumor cells invaded the lumen of the DED, and attached to the luminal wall in a ring shape; some tumor cells penetrated through the wall into the surrounding dermal tissue. On the bottom and lateral side of DED, tumor cells were infiltrating dispersedly.The tumor loci stained positive for S-100 protein and keratin, and weakly positive for HMB45. Conclusion Keratinocytes enhance the invasion of MV3 melanoma cells into the skin tissue model of melanoma.