Comparing open wound measuring methods popularly used in experimental studies / Estudo comparativo de métodos de avaliação de contração de feridas cutâneas abertas

Tissue repair is a response reaction to lesions and aggressions that constitutes a dynamic process to maintain the integrity of the organism. Wound healing experiments have used several approaches in order to assess and compare treatment methods, and these discrepancies hamper comparisons among assays. This study assessed three different methods of wound measurement commonly used in healing assays: clock method, graph paper method, and computer-assisted image analysis. We used 30 Wistar rats, kept in appropriate conditions for animal well-being. After anesthesia, and using an eight-millimeter punch, two lesions were made in the back region of each rat. The wounds were assessed on days four, seven, and 14 after infliction. At four days, all methods generated similar results. By day seven, the clock method had lost precision, likely due to wound shrinkage, and yielded greater means compared to the other two methods. On the last assessment, the computer-assisted method appeared to have more precise results, with the other two generating statistically higher means. Computer-assisted image analysis seems to have maintained wound measuring precision throughout this experiment, even when faced with small lesions. Considering these results, the authors recommend the use of computer-assisted measurements in future experiments.

O reparo tecidual surge em resposta às lesões e constitui-se de um processo dinâmico para manutenção da integridade do organismo. Nos estudos sobre cicatrização de feridas, tem se utilizado várias técnicas buscando-se uma avaliação da eficácia de meios de tratamento local. Sendo assim, o presente trabalho objetivou comparar três métodos de avaliação experimental de áreas de feridas, sendo eles: o método do relógio, papel milimetrado e avaliação computadorizada. Para realização do experimento, foram utilizados 30 ratos Wistar em condições de bem-estar. Após realizada a anestesia, foram confeccionadas duas lesões no dorso de cada animal com punch de 8 mm, sendo as feridas avaliadas após quatro, sete e 14 dias de tratamento. Observou-se que aos quatro dias de tratamento, todos os métodos apresentaram o mesmo desempenho, enquanto aos sete e 14 dias, o método do relógio, apresentou maior média de área, perdendo precisão, e aos 14 dias, a avaliação computadorizada apresentou resultados mais precisos em relação a ambos os outros métodos. Concluiu-se que a avaliação computadorizada através de software de áreas de feridas cutâneas apresenta resultados mais precisos em relação aos métodos do relógio e papel milimetrado, principalmente em lesões menores.

Moderate intensity physical training accelerates healing of full-thickness wounds in mice

Physical training influences the cells and mediators involved in skin wound healing. The objective of this study was to determine the changes induced by different intensities of physical training in mouse skin wound healing. Ninety male C57BL6 mice (8 weeks old, 20-25 g) were randomized into three physical training groups: moderate (70 percent VO2max), high (80 percent VO2max), and strenuous intensity (90 percent VO2max). Animals trained on a motorized treadmill for 8 weeks (Elesion: physical training until the day of excisional lesion, N = 10) or 10 weeks (Eeuthan: physical training for 2 additional weeks after excisional lesion until euthanasia, N = 10), five times/week, for 45 min. Control groups (CG) trained on the treadmill three times/week only for 5 min (N = 10). In the 8th week, mice were anesthetized, submitted to a dorsal full-thickness excisional wound of 1 cm², and sacrificed 14 days after wounding. Wound areas were measured 4, 7, and 14 days after wounding to evaluate contraction (d4, d7 and d14) and re-epithelialization (d14). Fragments of lesion and adjacent skin were processed and submitted to routine histological staining. Immunohistochemistry against alpha-smooth muscle actin (α-SMA) was performed. Moderate-intensity training (M) until lesion (M/Elesion) led to better wound closure 7 days after wounding compared to controls and M/Eeuthan (P < 0.05), and both moderate-intensity groups showed better re-epithelialization rates than controls (M/Elesion = 85.9 percent, M/Eeuthan = 96.4 percent and M/CG = 79.9 percent; P < 0.05). Sections of M/Elesion and M/Eeuthan groups stained with hematoxylin-eosin, Picrosirius red and α-SMA showed the most mature granulation tissues among all trained groups and controls. Thus, moderate-intensity physical training improves skin wound healing.

Evaluación biológica de dos hemostáticos locales / Biological evaluation of two local hemostatic agents

El objetivo del presente estudio fue evaluar la respuesta tisular del huésped a dos agentes hemostáticos locales, Pel Cupron y Hemostop. Los materiales fueron implantados en el tejido subcutáneo de ratas Wistar, en dos volúmenes 2.5 y 10 mg. durante 1, 3, 6, 15 y 30 días. Los resultados indicaron que ambos materiales retrasaron la cicatrización tisular, dando origen a reacciones de tipo cuerpo extraño. El análisis histométrico indicó que la respuesta inflamatoria estuvo directamente relacionada con la cantidad del agente implantado y el tipo de hemostático usado. Pel Cupron provocó una respuesta tisular más adversa, comparado con Hemostop

Biological phenomena within a pyramid model--a preliminary study on wound healing.

The Great pyramid of Egypt has evoked a keen interest, both for its architectural marvel and mystical significance. Strange things (viz sharpening of razors, longer shelflife of vegetables, altered states of consciousness in humans) are said to occur within a pyramid constructed in the exact geometric proportion to that of Great Pyramid and kept with any of its diagonals aligned north-south along the magnetic axis of the earth. Not much is available in the literature that have subjected "biological phenomenon within a pyramid" to the scientific scrutiny. This is just a preliminary study with that objective. Wound healing, being a physiological response of the body to injury, the measurement of 'breaking strength' of incisional wound offers an easy, objective method of assessing wound healing. The study consisted a 'control group' and 'a test group', each of 12 albino rats (Wistar). A paramedian 1" incisional wound was created in both the groups. The controls were kept in the usual rat cages while the 'test group' within a wooden pyramid (18" x 28.25" x 26.9"). The breaking strength of the wounds were assessed on the 10th post-wounding day using Kulkarni's modified Lee and Tong method and the results showed a significantly higher value (P < .05) for the test group. Further there was histological evidence of better wound healing in the test group.

Aspectos morfológicos e histométricos da reparaçäo tecidual das feridas cutâneas de ratos após irradiaçäo com o laser de hélio-neônio / Morphological and histometric aspects of tissue healing of skin wounds in rats after irradiation with the helium-neon laser

O objetivo foi avaliar a reparaçäo tecidual das feridas cutâneas de ratos após irradiaçäo com o Laser de Hélio-Neônio (He-Ne). Utilizamos 18 ratos machos, da linhagem Wistar. Dividimos os animais em 3 grupos de 6 animais: G1, G2, G3. Realizamos, em cada animal, duas feridas circulares de 1 cm na regiäo dorsal, sendo uma irradiada com o Laser de He-Ne na dose diária de 2,7 Joules/10 minutos, e a outra observada como controle. No 7§, 14§ e 21 dias as feridas foram analisadas quanto aos aspectos morfológicos e histométricos. Os resultados obtidos mostraram uma epitelizaçäo e contraçäo mais precoce das feridas irradiadas. A proporçäo de fibras colágenas foi maior nas feridas irradiadas nas 3 fases estudadas. A proporçäo de fibroblastos foi maior no grupo irradiadas nas 3 fases estudadas. A proporçäo de fibroblastos foi maior no grupo irradiado apenas no 7§ P. O. Concluímos que o processo de reparaçäo evoluiu de forma mais rápida nas feridas irradiadas em relaçäo ao controle