VEGETABLE CELLULOSE NANOFIBER DRESSING AIDS IN THE HEALING PROCESS OF THIRD-DEGREE BURNS? STUDY ON RATS.

BACKGROUND: The treatment of 3rd degree burns represents a major medical challenge. Pinus vegetable cellulose is a biomaterial with characteristic similar to bacterial cellulose. AIM: To evaluate the safety of cellulose membrane (Pinus sp) in the treatment of 3rd burns in rats and to compare its effectiveness with the bacterial membrane already on the market. METHOD: Thirty-three Wistar rats were beaten with a 3rd degree burn on back skin by applying water at 98º C for 30 s. Then, they were divided into three groups (n=11): group 1 - simple dressing with gauze; group 2 - dressing with bacterial cellulose membrane; and group 3 - dressing with vegetable cellulose membrane. The animals were maintained for 15 days to check the general clinical status, macroscopic aspect, contraction of the wounds and microscopic analysis for the degree of healing and collagenization. RESULTS: They were clinically well during the experiment. During the removal of the dressing, there was bleeding in the wound of the control group, unlike the groups treated with cellulose membranes, which protected the bed from injury. The macroscopic evaluation showed a greater contraction of the wounds treated with the membranes in relation to the control. A microscopic analysis revealed that most of the wounds were in advanced healing degree with predominance of mature collagen in all groups. CONCLUSION: Pinus sp cellulose membrane showed efficacy similar to that of the bacterial membrane in the treatment of 3rd degree burns.

PINE NANOCELLULOSE AND BACTERIAL NANOCELLULOSE DRESSINGS ARE SIMILAR IN THE TREATMENT OF SECOND-DEGREE BURN? EXPERIMENTAL STUDY IN RATS.

BACKGROUND: Crusts in 7th follow-up day: G1 yes; G2 no; G3 no (left to right). Bespite all the advances in medicine and the wide variety of dressings available, the treatment of burn wounds still represents an important medical challenge. The pinus cellulose membrane dressing is a biomaterial with characteristics similar to those of bacterial cellulose, but with lower cost. AIM: To evaluate the efficacy of pinus nanocellulose membrane on healing of deep second degree burns in rats and compare with Membracel®. METHOD: Thirty male Wistar rats were submitted to deep second degree burn in dorse, with boiling water at 97o C for 20 s, generating a 314 mm² area wound. The animals were distributed in three dressing groups (n=10): group 1 - simple gauze; group 2 - bacterial cellulose membrane (Membracel®); and group 3 - pinus cellulose membrane. They were evaluated for 20 days to verify clinical condition, macro and microscopic appearance and wound contraction. RESULTS: All of them remained clinically well with no differences in weight. Crusts were observed in group 1, and none in groups 2 and 3. Regarding to scar contraction, groups 2 and 3 were similar, better than group 1. Microscopic analysis showed predominance of advanced healing degree in groups 1 and 3, and initial in group 2. Mature collagen was predominant in all groups. CONCLUSION: The pinus nanocellulose membrane is effective in the treatment of experimental second degree burn in rats and its effectiveness is similar to that of the bacterial nanocellular membrane.

Vegetable cellulose nanofiber dressing aids in the healing process of third-degree burns? study on rats / Curativo de nanofibras de celulose vegetal auxilia na cicatrização de queimaduras de terceiro grau? estudo em ratos

ABSTRACT Background: The treatment of 3rd degree burns represents a major medical challenge. Pinus vegetable cellulose is a biomaterial with characteristic similar to bacterial cellulose. Aim: To evaluate the safety of cellulose membrane (Pinus sp) in the treatment of 3rd burns in rats and to compare its effectiveness with the bacterial membrane already on the market. Method: Thirty-three Wistar rats were beaten with a 3rd degree burn on back skin by applying water at 98º C for 30 s. Then, they were divided into three groups (n=11): group 1 - simple dressing with gauze; group 2 - dressing with bacterial cellulose membrane; and group 3 - dressing with vegetable cellulose membrane. The animals were maintained for 15 days to check the general clinical status, macroscopic aspect, contraction of the wounds and microscopic analysis for the degree of healing and collagenization. Results: They were clinically well during the experiment. During the removal of the dressing, there was bleeding in the wound of the control group, unlike the groups treated with cellulose membranes, which protected the bed from injury. The macroscopic evaluation showed a greater contraction of the wounds treated with the membranes in relation to the control. A microscopic analysis revealed that most of the wounds were in advanced healing degree with predominance of mature collagen in all groups. Conclusion: Pinus sp cellulose membrane showed efficacy similar to that of the bacterial membrane in the treatment of 3rd degree burns.

RESUMO Racional: O tratamento das queimaduras de 3˚ grau representa grande desafio na área médica. A celulose vegetal de pinus é biomaterial com características semelhantes às da celulose bacteriana. Objetivo: Avaliar a segurança da membrana de celulose vegetal (Pinus sp) no tratamento de queimaduras de terceiro grau em ratos e comparar sua eficácia com a da membrana bacteriana já comercializada. Método: Trinta e três ratos Wistar foram submetidos à queimadura de 3º grau na pele do dorso mediante aplicação de água a 98º C durante 30 s. Em seguida, foram distribuídos em três grupos (n=11): grupo 1 - curativo simples com gaze; grupo 2 - curativo com membrana de celulose bacteriana; e grupo 3 - curativo com membrana de celulose vegetal . Os animais foram avaliados durante 15 dias para verificar o estado clínico geral, aspecto macroscópico, contração das feridas e análise microscópica pelo grau de cicatrização e colagenizacao. Resultados: Permaneceram clinicamente bem durante o experimento. Durante a retirada do curativo houve sangramento na ferida do grupo controle, diferentemente dos grupos tratados com as membranas de celulose, que protegeram o leito da lesão. A análise microscópica mostrou que a maioria das feridas apresentava-se em grau avançado de cicatrização, com predomínio de colágeno maduro em todos os grupos. Houve maior contração das feridas tratadas com as membranas em relação ao grupo controle. Conclus ão: A membrana de celulose de Pinus sp apresentou eficácia semelhante à da membrana bacteriana no tratamento de queimaduras de 3˚ grau.

Closure of large wounds using rubber bands in rabbits.

OBJECTIVE: to verify the effectiveness of the rubber elastic band in the treatment of large wounds of the body wall of rabbits by means of traction of its edges. METHODS: we studied 30 New Zealand rabbits, divided into three groups (n=10): Group 1- healing by secondary intention; Group 2- removal and eutopic repositioning of skin as full thickness skin graft; Group 3- Approximation of wound edges with elastic rubber band. In all animals, we removed a segment of the back skin and subcutaneous tissue down to the fascia, in accordance with an acrylic mold of 8 cm long by 12 cm wide. All animals were observed for 21 days. RESULTS: two animals of groups 1 and 2 had wound abscess. In Group 2, there was partial or total graft loss in 90% of animals. The complete closure of the wounds was observed in four animals of Group 1, six of Group 2 and eight of Group 3. There was no difference between the scar resistance values of groups 2 and 3, which were higher than those in Group 1. The scars of the three groups were characterized by the presence of mature connective tissue mixed with blood vessels and inflammatory infiltration, predominantly polymorphonuclear. CONCLUSION: the tensile strength of the wound edges with rubber elastic band is as efficient as the skin graft to treat rabbits' large body wounds.

Pine nanocellulose and bacterial nanocellulose dressings are similar in the treatment of second-degree burn? experimental study in rats / Os curativos de nanocelulose de pinus e nanocelulose bacteriana são semelhantes no tratamento da queimadura de segundo grau? estudo experimental em ratos

ABSTRACT Background: Despite all the advances in medicine and the wide variety of dressings available, the treatment of burn wounds still represents an important medical challenge. The pinus cellulose membrane dressing is a biomaterial with characteristics similar to those of bacterial cellulose, but with lower cost. Aim: To evaluate the efficacy of pinus nanocellulose membrane on healing of deep second degree burns in rats and compare with Membracel®. Method: Thirty male Wistar rats were submitted to deep second degree burn in dorse, with boiling water at 97o C for 20 s, generating a 314 mm² area wound. The animals were distributed in three dressing groups (n=10): group 1 - simple gauze; group 2 - bacterial cellulose membrane (Membracel®); and group 3 - pinus cellulose membrane. They were evaluated for 20 days to verify clinical condition, macro and microscopic appearance and wound contraction. Results: All of them remained clinically well with no differences in weight. Crusts were observed in group 1, and none in groups 2 and 3. Regarding to scar contraction, groups 2 and 3 were similar, better than group 1. Microscopic analysis showed predominance of advanced healing degree in groups 1 and 3, and initial in group 2. Mature collagen was predominant in all groups. Conclusion: The pinus nanocellulose membrane is effective in the treatment of experimental second degree burn in rats and its effectiveness is similar to that of the bacterial nanocellular membrane.

RESUMO Racional: Apesar de todos os avanços da medicina e da grande variedade de curativos disponíveis, o tratamento das queimaduras ainda representa importante desafio médico. O curativo de membrana de celulose de pinus é biomaterial com características semelhantes à de celulose bacteriana, mas de menor custo. Objetivo: Avaliar a eficácia da membrana de nanocelulose de pinus na cicatrização de queimaduras profundas de segundo grau em ratos e comparar com a Membracel®. Método: Trinta ratos Wistar machos foram submetidos à queimadura profunda de segundo grau em dorso, com água fervente a 97o C por 20 s, gerando lesão de 314 mm². Os animais foram distribuídos em três grupos de curativos (n = 10): grupo 1 - gaze simples; grupo 2 - membrana de celulose bacteriana (Membracel®); e grupo 3 - membrana de celulose de pinus. Eles foram avaliados por 20 dias para verificar o quadro clínico, aspecto macro e microscópico e a contração da ferida. Resultados: Todos permaneceram clinicamente bem, sem diferenças de peso. Crostas foram observadas no grupo 1 e nenhuma nos grupos 2 e 3. Em relação à contração da cicatriz, os grupos 2 e 3 foram semelhantes, melhores que o grupo 1. A análise microscópica mostrou predomínio de grau de cicatrização avançado nos grupos 1 e 3, e inicial no grupo 2. O colágeno maduro foi predominante em todos os grupos. Conclusão: A membrana de nanocelulose de pinus é eficaz no tratamento de queimaduras experimentais de segundo grau em ratos e sua eficácia é semelhante à da membrana nanocelular bacteriana.

Closure of large wounds using rubber bands in rabbits / Fechamento de grandes feridas com fita elástica de borracha em coelhos

OBJECTIVE: To verify the effectiveness of the rubber elastic band in the treatment of large wounds of the body wall of rabbits by means of traction of its edges. METHODS: we studied 30 New Zealand rabbits, divided into three groups (n=10): Group 1- healing by secondary intention; Group 2- removal and eutopic repositioning of skin as full thickness skin graft; Group 3- Approximation of wound edges with elastic rubber band. In all animals, we removed a segment of the back skin and subcutaneous tissue down to the fascia, in accordance with an acrylic mold of 8cm long by 12cm wide. All animals were observed for 21 days. RESULTS: two animals of groups 1 and 2 had wound abscess. In Group 2, there was partial or total graft loss in 90% of animals. The complete closure of the wounds was observed in four animals of Group 1, six of Group 2 and eight of Group 3. There was no difference between the scar resistance values of groups 2 and 3, which were higher than those in Group 1. The scars of the three groups were characterized by the presence of mature connective tissue mixed with blood vessels and inflammatory infiltration, predominantly polymorphonuclear. CONCLUSION: the tensile strength of the wound edges with rubber elastic band is as efficient as the skin graft to treat rabbits' large body wounds.

OBJETIVOS: Verificar a eficácia da fita elástica de borracha no tratamento de grandes feridas de parede corpórea de coelhos por meio da tração de suas bordas. MÉTODOS: foram estudados 30 coelhos da raça Nova Zelândia, distribuídos em três grupos (n=10): Grupo 1. Cicatrização por segunda intenção. Grupo 2. Retirada e reposicionamento eutópico da pele como enxerto de pele total. Grupo 3. Aproximação das bordas da ferida com fita elástica de borracha. Em todos os animais, foi retirado segmento de pele e tecido subcutâneo até a fáscia musculoaponeurótica do dorso, de acordo com um molde de acrílico, com 12cm de comprimento por 8cm de largura. Todos os animais foram acompanhados durante 21 dias. RESULTADOS: dois animais dos grupos 1 e 2 apresentaram abscesso na ferida. No Grupo 2, houve perda parcial ou total do enxerto em 90% dos animais. O fechamento completo das feridas foi observado em quatro animais do Grupo 1, seis do Grupo 2 e oito do Grupo 3. Não houve diferença entre os valores de resistência cicatricial dos grupos 2 e 3, que foram maiores do que os do Grupo 1. As cicatrizes dos três grupos caracterizaram-se pela presença de tecido conjuntivo maduro entremeado por vasos sanguíneos e infiltrado inflamatório, predominantemente polimorfonuclear. CONCLUSÃO: a tração das bordas da ferida com fita elástica de borracha constitui método tão eficaz quanto o enxerto de pele para tratar grandes feridas de parede corpórea de coelhos.