Valproic acid and bladder healing: an experimental study in rats / Ácido valpróico e cicatrização em bexiga: estudo experimental em ratos

ABSTRACT Purpose: to recognize the effects of valproic acid (VPA), an epigenetic drug, on the bladder healing process, in rats. Method: twenty male Wistar rats were divided in two groups: experimental (A), treated with VPA (150mg/Kg/day), and control (B) with 0.9% sodium chloridrate. Healing was analyzed on the third and seventh days, evaluating the inflammatory reaction, collagen synthesis and angiogenesis. Results: inflammatory reaction on the third day was minimal and acute in both groups. On the seventh day, it was subacute in both groups, moderate intensity in group A and minimal in group B (p=0.0476). Collagen III intensity, marked by immunohistochemistry, was similar in both groups. Collagen I intensity on the third day was similar in both groups, but on the seventh day it was higher in experimental than control (p=0.0476). Collagen evaluation by picrosiriusred allowed to verify that the presence of collagen III was similar in both groups (p=0.3312) on the third day, and it was higher in control on the seventh day (p=0.0015). Collagen I showed similarity on the third day (p=0.3100), and it was higher in control on the seventh day (p=0.0015). Vessel marked with anti-SMA counting showed fewer vessels on the third (p=0.0034) and seventh day (p=0.0087) in experimental group. The lower intensity of angiogenesis was confirmed with anti-CD34, on the third day (p=0,0006) and on the seventh day (p=0,0072). Conclusion: VPA determined alterations in the bladder healing process, in rats, with lower collagen density and less angiogenic activity, but without compromising the integrity of the organ.

RESUMO Objetivo: reconhecer os efeitos do ácido valpróico (VPA), uma droga epigenética, no processo de cicatrização da bexiga, em ratos. Método: vinte ratos Wistar machos foram divididos em dois grupos: experimental (A), utilizando VPA (150mg/Kg/dia), e controle (B), tratados com cloreto de sódio 0,9% por gavagem. A cicatrização da bexiga foi analisada no terceiro e sétimo dia, estudando-se a reação inflamatória, síntese de colágeno, reepitelização e angiogênese. Resultados: a reação inflamatória no terceiro dia foi mínima e aguda em ambos os grupos. No sétimo dia, foi subaguda em ambos os grupos com intensidade moderada no grupo A e mínima no grupo B (p=0,0476). A intensidade do colágeno III, marcada pela imuno-histoquímica, foi semelhante nos dois grupos, nos dois tempos estudados. A intensidade de colágeno I no terceiro dia foi semelhante nos dois grupos, e maior no sétimo dia no grupo experimental (p=0,0476). A avaliação do colágeno pelo picrosiriusred mostrou que a presença de colágeno III foi semelhante em ambos os grupos (p=0,3312) no terceiro dia, e maior no controle no sétimo dia (p=0,0015). O colágeno I foi semelhante no terceiro dia (p=0,3100), e maior no controle no sétimo dia (p=0,0015). A contagem de vasos marcados pelo anti-SMA mostrou menos vasos no terceiro (p=0,0034) e sétimo dia (p=0,0087) no grupo experimental, confirmado pelo anti-CD34, no terceiro (p=00006) e no sétimo dia (p=0,0072). Conclusão: o VPA determinou alterações no processo de cicatrização da bexiga, em ratos, com menor densidade de colágeno e menor atividade angiogênica, mas sem comprometer a integridade do órgão.

Acetylsalicylic acid (Aspirin®) and liver regeneration: experimental study in rats / Ácido acetilsalicílico (Aspirina®) e regeneração hepática: estudo experimental em ratos

ABSTRACT Objective: to evaluate the influence of acetylsalicylic acid (ASA) on cell proliferation after partial hepatectomy in rats. Methods: 40 male Wistar rats were separated into four groups of ten rats each. Groups 1 and 2 (controls): undergoing 30% partial hepatectomy and, after one day (group 1) and seven days (group 2), to euthanasia; daily administration of 0.9% saline solution (1mL per 200g of body weight). Groups 3 and 4 (experimental): undergoing 30% partial hepatectomy and, after one day (group 3) and seven days (group 4), to euthanasia; daily administration of ASA (40mg/mL, 1mL per 200g of body weight). The absolute number of cells stained with PCNA was counted in photomicrographs, in five fields, and it was calculated the mean of positive cells per animal and per group. Results: the final mean of PCNA+ cells per group was: in group 1, 17.57 ± 6.77; in group 2, 19.31 ± 5.30; in group 3, 27.46 ± 11.55; and, in group 4, 12.40 ± 5.23. There was no significant difference at the two evaluation times in the control group (p=0.491), but there was in the experimental group (p=0.020), with a lower number of PCNA+ cells on the seventh day. The comparison between the two groups, on the first day, showed more PCNA+ cells in the livers of the animals that received ASA (p=0.047), and on the seventh day the number was lower in the experimental group (p=0.007). Conclusion: ASA induced greater hepatocyte proliferation.

RESUMO Objetivo: avaliar a influência do ácido acetilsalicílico (AAS) na proliferação celular após hepatectomia parcial em ratos. Métodos: 40 ratos Wistar machos foram separados em quatro grupos com dez ratos cada. Grupos 1 e 2 (controles): submetidos à hepatectomia parcial de 30% e, após um (grupo 1) e sete dias (grupo 2), à eutanásia; administração diária de solução fisiológica 0,9% (1mL por 200g de peso). Grupos 3 e 4 (experimentos): submetidos à hepatectomia parcial de 30% e, após um (grupo 3) e sete dias (grupo 4), à eutanásia; administração diária de AAS (40mg/mL, 1mL por 200g de peso). Realizou-se a contagem do número absoluto de células coradas com PCNA em fotomicrografias, em cinco campos e cálculo da média de células positivas por animal e por grupo. Resultados: A média final de células PCNA+ por grupo foi: no grupo 1, de 17,57 ± 6,77; no grupo 2 de 19,31 ± 5,30; no grupo 3, de 27,46 ± 11,55; e, no grupo 4, de 12,40 ± 5,23. Não houve diferença significante nos dois tempos de avaliação no grupo controle (p=0,491), mas houve no grupo experimento (p=0,020), observando-se menor número de células PCNA+ no sétimo dia. A comparação entre os dois grupos, no primeiro dia, mostrou mais células PCNA+ nos fígados dos animais que receberam AAS (p=0,047), e no sétimo dia o número foi menor no grupo experimento (p=0,007). Conclusão: O AAS induziu maior proliferação hepatocitária.

Biological compatibility of oxidized cellulose vs. porcine gelatin to control bleeding in liver lesions in rats

ABSTRACT Purpose: To compare biological compatibility, hemostasis, and adhesion formation between oxidized regenerated cellulose and lyophilized hydrolyzed porcine collagen in liver trauma. Methods: Forty male Wistar rats constituted two groups: group A (oxidized cellulose) and group B (lyophilized hydrolyzed collagen). Standardized liver trauma was made, and the hemostatic agent was applied. Animals in subgroups A7 and B7 were submitted to euthanasia and relaparotomy after seven days, and in subgroups A14 and B14 after 14 days. Macroscopic and microscopic results were evaluated. Results: There was no fluid in the cavity in any of the animals, and adhesions were present in all of them. In the analysis after seven days, the adhesions were grades 3 or 4 and consisted of omentum, small intestine, and abdominal wall (p<0.05). In both groups, the mesh was surrounded by a capsule, which was not observed after 14 days. In the evaluation after 14 days, adhesions were grades 2 or 3 (p>0.05). The microscopic examination showed subacute and chronic reactions, in both groups and in both timepoints, with similar frequency. The intensity of fibrosis always presented positive scores. Microabscesses and xanthomatous macrophages were observed in both groups. Conclusions: There was no superiority of one agent over the other.

Análise comparativa dos efeitos do mel, do óleo-serina de copaíba e de um produto comercial (fibrinolisina, desoxirribonuclease e cloranfenicol) na cicatrização por segunda intenção, em ratos / Comparative analysis of the effects of honey, copaiba oil-resin and a commercial product (fibrinolysin, deoxyribonuclease and chloramphenicol) on second intention healing, in rats

RESUMO Objetivo: comparar a cicatrização, por segunda intenção, sob os efeitos da aplicação tópica de mel, óleo-resina de copaíba e um produto comercial (fibrinolisina, desoxirribonuclease e cloranfenicol) a um grupo controle, em ratos. Métodos: ressecção de pele, com 1cm de diâmetro, foi realizada no dorso de 40 ratos alocados em quatro grupos de dez animais. Todas as feridas foram limpas, diariamente, com 2ml de solução de NaCl 0,9%. O primeiro grupo (controle - GC) ficou restrito a tal procedimento. Nas feridas do segundo (GM), terceiro (GO) e quarto grupos (GF), após limpeza, aplicou-se, respectivamente, 1ml de mel, 1ml de óleo-resina de copaíba e 1ml de creme contendo fibrinolisina, desoxirribonuclease e cloranfenicol. Ocluíram-se as feridas com gaze estéril. Imediatamente após a incisão e nos dias três, sete e 14 do experimento, as feridas foram copiadas e, usando planimetria, analisou-se a contração. Após a eutanásia, a histologia foi utilizada para avaliação da reação inflamatória e do colágeno nas cicatrizes. Resultados: a redução da área da ferida do GM (p=0,003), GO (p=0,011) e GF (p=0,002) foram superiores ao do GC. A quantidade de colágeno tipo I presente no GM e no GO foi superior aos grupos GC e GF (p<0,05). Houve predominância do estágio inflamatório crônico no GM (p=0,004), GO (p<0,001) e GF (p=0,003) quando comparados ao GC. Conclusão: o uso tópico do mel e do óleo-resina de copaíba aumenta a contração da ferida, a presença de colágeno tipo I e acelera a cicatrização.

ABSTRACT Objective: to compare the healing by second intention under the effects of topical application of honey, copaíba oil-resin and a commercial product (fibrinolysin, deoxyribonuclease and chloramphenicol) with a control group in rats. Methods: we carried out a skin resection, 1cm in diameter, on the back of 40 rats allocated to four groups of ten animals. All wounds were cleaned daily with 2ml of 0.9% NaCl solution. The first group (control - GC) was restricted to such procedure. In the wounds of the second (GM), third (GO) and fourth groups (GF), after cleaning, we respectively applied 1ml of honey, 1ml of copaíba oil-resin and 1ml of cream containing fibrinolysin, deoxyribonuclease and chloramphenicol. The wounds were occluded with sterile gauze. Immediately after the incision and on days three, seven and 14 of the experiment, the wounds were copied and contraction was analyzed using planimetry. After euthanasia, we histologically evaluated the inflammatory reaction and collagen in the scars. Results: the reduction of the wound area of GM (p=0.003), GO (p=0.011) and GF (p=0.002) were higher than the GC. The amount of type-I collagen present in GM and GO was higher than in GC and GF groups (p<0.05). There was a predominance of chronic inflammatory stage in GM (p=0.004), GO (p<0.001) and GF (p=0.003) when compared with GC. Conclusion: the topical use of honey and copaíba oil-resin increases wound contraction, the presence of type-I collagen and accelerates healing.

Metronidazole concentration in the bloodstream following its topical application, at different concentration levels, on experimental skin wounds during healing by secondary intention

Abstract Purpose: To characterize qualitatively and quantitatively the absorption of metronidazole solution, in greater concentrations and for longer periods, when applied topically to an experimental open skin wound model. Methods: An open skin wound, 2 cm in diameter and total skin thickness was prepared, under anesthetic, in the dorsal region of 108 Wistar rats weighing between 300 and 350 grams. The animals were allocated to groups of 18 animals in accordance with the concentration of metronidazole in the solution to be applied daily to the wound. In the control group (CG), 0.9% sodium chloride solution was used for application, and in the experimental groups (GI, GII, GIII, GIV and GV) metronidazole solution at 4%, 6%, 8%, 10% and 12%, respectively, was applied. After 3, 7 and 14 days of treatment. Blood samples collected through cardiac puncture were examined for the existence or non-existence of metronidazole, using high performance liquid chromatography (HPLC). Detected metronidazole values were compared statistically within each group (temporal analysis 3 days X 7 days X 14 days) and between the groups that used topical metronidazole (4% X 6% X 8% X 10% and 12%) using the Kruskal-Wallis test, considering a statistical significance of 95% (p<0.05). Results: Metronidazole was detected in all the samples at all times in all the groups in which topical metronidazole was applied to the wounds. Characteristically, there was no significant difference between the doses obtained within each group over time (3 days X 7 days X 14 days) GI=0.461; GII=0.154; GIII=0.888; GIV= 0.264 and GV=0.152. In the evaluation between groups, a similar degree of absorption was found after 3 days (p=0.829) and 14 days (p=0.751). Conclusion: The serum concentration of metronidazole that was achieved was not influenced by the concentration of the solution applied to the skin wound, with similar extend, or by the duration of the application.

Diferenciação de miofibroblastos em feridas após uso tópico do metronidazol: estudo experimental / Differentiation of myofibroblasts in wounds after topical use of metronidazole: an experimental study

RESUMO Objetivo: avaliar os efeitos da administração tópica do metronidazol na diferenciação de fibroblastos e na contração da ferida durante cicatrização experimental por segunda intenção em ratos. Métodos: cento e oito animais foram submetidos a uma ferida circular no dorso, com 2cm de diâmetro e divididos em seis grupos: grupo controle, com aplicação de solução salina sobre a ferida e cinco grupos experimentais divididos de acordo com a concentração da solução do metronidazol utilizada (4%, 6%, 8%,10% e 12%). Curativos foram realizados diariamente durante todo o período do experimento, que foi subdividido em três momentos de análise: três, sete e 14 dias. A contração da ferida foi avaliada por planimetria digital e os miofibroblastos e protomiofibroblastos foram identificados usando técnicas de imuno-histoquímica CD34 e a-SMA. Resultados: a contração da ferida não apresentou diferença entre os grupos e o controle. Os protomiofibroblastos foram significativamente mais numerosos aos sete dias (p=0,022) nos grupos metronidazol de 4%, 6% e 8%. Após 14 dias, nos mesmos grupos, os miofibroblastos predominaram significativamente (p=0,01). Conclusão: a administração tópica de solução de metronidazol em feridas de pele com cicatrização por segunda intenção foi capaz de melhorar a diferenciação de fibroblastos. A fase de contração da cicatrização de feridas permaneceu inalterada, sem redução significativa da contração avaliada pela planimetria digital. Estes resultados podem ser utilizados em favor do processo de cicatrização de feridas.

ABSTRACT Objective: to assess the effects of topical administration of metronidazole on fibroblast differentiation and on wound contraction during experimental secondary intention wound healing in rats. Methods: we submitted 108 rats to a circular wound on the back, 2cm in diameter, and divided them into six groups: control group, with application of saline solution on the wound and five experimental groups, divided according to the concentration of metronidazole solution used (4%, 6%, 8%, 10% and 12%). We changed the dressings daily throughout the trial period, which comprised three stages of analysis: three, seven and 14 days. We evaluated wound contraction by digital planimetry, and identified myofibroblasts and protomyofibroblasts using CD34 and α-SMA immunohistochemistry techniques. Results: wound contraction was not different between the experimental and the control groups. Protomyofibroblasts were significantly more numerous at seven days (p=0.022) in the 4%, 6% and 8% metronidazole groups. After 14 days, in the same groups, myofibroblasts predominated significantly (p=0.01). Conclusion: the topical administration of metronidazole solution in skin wounds healing by secondary intention was able to improve the differentiation of fibroblasts. The contraction phase of wound healing remained unchanged, without significant reduction of the contraction evaluated by digital planimetry. These results can be used in favor of the wound healing process.

Comparative study of fibrosis induced by Marlex®, Parietex Composite®, Vicryl® and Ultrapro® meshes1

Abstract Purpose: To evaluate the fibrosis induced by four different meshes: Marlex®, Parietex Composite®, Vicryl® and Ultrapro®. Methods: Histological cutouts of abdominal wall were analyzed with polarized light 28 days after the meshes implants and colorized by picrosirius to identify the intensity of collagen types I and III, and their maturation index. Results: When the four groups were compared, the total collagen area analyzed was bigger in groups A and D, with no difference between them. The collagen type I density was bigger in group A, with an average of 9.62 ± 1.0, and smaller in group C, with an average of 3.86 ± 0.59. The collagen type III density was similar in groups A, B and C, and bigger in group D. The collagen maturation index was different in each of the four groups, bigger in group A with 0.87, group B with 0.66, group D with 0.57 and group C with 0.33 (p = 0.0000). Conclusion: The most prominent fibrosis promotion in the given meshes was found on Marlex® (polypropylene mesh) and the Parietex Composite® (non-biodegradable polyester); the collagen maturation index was higher in the Marlex® mesh, followed by Ultrapro®, Parietex Composite® and Vicryl® meshes.

Comparative study of polyglactin 910 and simple catgut in the formation of intraperitoneal adhesions

Abstract Purpose: To compare polyglactin 910 and simple catgut sutures for the incidence of intraperitoneal adhesions. Methods: Twenty female Wistar rats were placed into two groups. Group 1 received ischemic sutures and Group 2 received polyglactin 910. Five sutures inductive of adhesions in each rat were made. After 14 days, the rats were euthanized with an assessment of the presence of adhesions, the number of sutures involved and classification according to the Granat et al. scale described by Ozel et al17. Results: In total, 19 of the 20 rats presented adhesions, with nine from Group 1 and ten from Group 2. There was a smaller number of affected sutures in Group 1, while in Group 2 the majority of the sutures formed adhesions (p=0.0197). According to the Granat et al. scale, Group 1 predominately developed fine, filamentous adhesions or thickening in a restricted area. Group 2 mainly presented extensive, thick adhesions with the involvement of the viscera (p=0.0055). Conclusion: Polyglactin 910 sutures formed more adhesions that were more extensive and thicker than the simple catgut sutures.

Aderências em telas de polipropileno versus telas Sepramesh®: estudo experimental em ratos / Adhesions on polypropylene versus Sepramesh® meshes: an experimental study in rats

RESUMO Objetivo: comparar a formação de aderências intraperitoneais, induzidas em ratos, quando utilizadas as telas de polipropileno e Sepramesh®. Métodos: foram utilizados 20 ratos Wistar, machos, agrupados randomicamente em dois grupos de dez animais cada. Duas telas de dimensão 10x20mm foram dispostas intraperitonealmente em cada animal, uma de polipropileno (PP) e a outra Sepramesh®. No Grupo 1, a tela de polipropileno foi posicionada à direita e a tela Sepramesh® à esquerda. No Grupo 2, a disposição das telas foi invertida. Após 14 dias do procedimento, os animais foram eutanasiados e a incorporação e a porcentagem de aderências, em cada tela, analisadas macroscopicamente. Os dados coletados foram submetidos à análise estatística com nível de significância adotado de p<0,05. Resultados: todas as telas apresentaram aderências. Nas telas Sepramesh®, a porcentagem de superfície coberta por aderências variou entre 2% e 86%, com média de 18,6±18,6%, enquanto que, nas telas de polipropileno, variou entre 6% e 86%, com média de 57,4%±34,9% (p<0,05). Os sítios preferenciais de formação de aderências, em ambas as telas, foram as bordas. Conclusão: embora nenhuma tela tenha sido capaz de inibir completamente o desenvolvimento de aderências, a tela Sepramesh® apresentou menos aderências em relação à tela de polipropileno. A preferência da formação de aderências nas bordas das próteses evidencia a importância da fixação adequada das telas.

ABSTRACT Objective: to compare the formation of induced intraperitoneal adhesions in rats when using polypropylene and Sepramesh® meshes. Methods: we used 20 male Wistar rats, randomly grouped in two groups of ten animals each. We arranged two 10x20mm meshes intraperitoneally into each animal, one being the polypropylene (PP), and the other, Sepramesh®. In Group 1, the polypropylene mesh was positioned to the right, and the Sepramesh®, to the left. In Group 2, the meshes' layout was reversed. After 14 days of the procedure, we euthanized the animals and analyzed the incorporation and percentages of adhesions macroscopically in each mesh. We submitted the collected data to statistical analysis with a significance level of 5% (p<0.05). Results: all meshes showed adhesions. In the Sepramesh® ones, the percentage of surface covered by adhesions ranged from 2% to 86%, with a mean of 18.6±18.6%, while in the polypropylene meshes, it varied between 6% and 86%, with an average of 57.4%±34.9% (p<0.05). The preferred adhesion sites on both meshes were the edges. Conclusion: although no mesh was able to completely inhibit the development of adhesions, the Sepramesh® mesh presented less adhesions to the polypropylene mesh. The most common sites of adhesion formation were the edges of the prosthesis, which evidences the importance of the adequate fixation of the meshes.

Comparative study of Polypropylene versus Parietex composite®, Vicryl® and Ultrapro® meshes, regarding the formation of intraperitoneal adhesions

Abstract Purpose: To compare the polypropylene mesh (Marlex®) to Vicryl®, Parietex composite® and Ultrapro® meshes to assess the occurrence of adhesions in the intraperitoneal implantation. Methods: Sixty Wistar rats were allocated into three groups: PP+V, in which all the animals received a polypropylene and a Vicryl® mesh; PP+PC, with the implantation of polypropylene and Parietex composite® meshes and PP+UP, in which there was implantation of polypropylene and Ultrapro®. Macroscopic analysis was performed 28 days later to assess the percentage of mesh area affected by adhesion. Results: in the PP+ V group, the Vicryl® mesh showed lower adhesion formation (p=0.013). In the PP+PC, there were no differences between polypropylene and Parietex composite® (p=0.765). In the PP+UP group, Ultrapro® and polypropylene meshes were equivalent (p=0.198) . Conclusion: All the four meshes led to adhesions, with the Vicryl® mesh showing the least potential for its formation.

Characteristics of the fibroplasia and collagen expression in the abdominal wall after implant of the polypropylene mesh and polypropylene/polyglecaprone mesh in rats

ABSTRACT PURPOSE: To compare fibroplasia and the resistance of the abdominal wall when polypropylene meshes and polypropylene/poliglecaprone are used. METHODS: Seventy-seven male Wistar rats were divided into three groups: Control Group (for resistance); Group E (polypropylene mesh); and Group U (polypropylene/poliglecaprone mesh). The animals in Groups E and U had a standard muscular and aponeurotic defect, with integral peritoneum, and correction with the mesh. Measurements were taken 4, 7, 14, 28 and 56 days after surgery. The resistance, and collagen density were studied. RESULTS: Resistance on the 56th day was similar in both meshes. The gain in resistance described an ascending curve for the polypropylene mesh and was irregular in the case of the polypropylene/poliglecaprone. Fibroplasia showed a gain in type I and type III collagen in both groups (p<0.001). Collagen III stabilized in the 14th day and collagen I continued to ascend. CONCLUSIONS: The gain in resistance of the polypropylene mesh is regular and ascending, whereas the polypropylene/poliglecaprone is not regular. The final resistance of both meshes is similar; the collagen density increases over time, and show the same inflammatory potential.

Inflammatory reaction and tensile strength of the abdominal wall after an implant of polypropylene mesh and polypropylene/poliglecaprone mesh for abdominal wall defect treatment in rats

PURPOSE: To compare the inflammatory reaction and the growing resistance of the abdominal wall with the use of poliglecaprone meshes and polypropylene meshes associated with poliglecaprone in the correction of abdominal defects. METHODS: Seventy-seven Wistar rats were divided into three groups: CG (non-operated animals: EG (polypropylene mesh) and UG (polypropylene and poliglecaprone mesh). A muscular and aponeurotic defect was formed and treated according to the group. Evaluations were made after 4, 7, 14, 28 and 56 days. The resistance and inflammatory pattern were studied. RESULTS: There was a gradual and significant gain in resistance, regularly in the EG and irregularly in the UG, which was lower on the 14th day (p=0.008). The inflammatory reaction was acute and more intense in the UG on the fourth day. At all other times, the inflammatory pattern was acute to chronic, similar in both groups, with minimum intensity on the 56th day. CONCLUSION: The greater resistance offered by the polypropylene mesh was regular and ascending, stabilizing on the 28th day, while that of the polypropylene/poliglecaprone was not even. In the end, the resistances were similar. The inflammatory response was greater in the UG on the fourth day and similar at all other times. .

Influência do envelhecimento na qualidade da pele de mulheres brancas: o papel do colágeno, da densidade de material elástico e da vascularização / Influence of aging on the skin quality of white-skinned women: the role of collagen, elastic material density, and vascularization

INTRODUÇÃO: O objetivo deste estudo é avaliar a influência do envelhecimento na qualidade da pele de mulheres brancas, analisando o colágeno, as fibras elásticas e a vascularização. MÉTODO: Foi realizada análise histológica e morfométrica de 218 retalhos pré-auriculares de mulheres brancas, que se submeteram a cirurgia estética facial. Foram utilizados o imunomarcador AntiCD 34, que evidencia os vasos sanguíneos, a coloração de Weigert, para visibilização das fibras elásticas, e a coloração de Picrosirius Ultrared, para analisar e quantificar os colágenos I, III e total. Os dados foram analisados de acordo com a faixa etárias das doadoras: < 40 anos, 40 anos a 49 anos, 50 anos a 59 anos, 60 anos a 69 anos, e > 70 anos. RESULTADOS: Foi observada fragmentação e desorganização das fibras de colágeno, especialmente acima de 60 anos. Não houve diferenças significantes entre a idade e a espessura da derme e da epiderme, porém foi identificada relação com as porcentagens de colágeno I, III e total (P < 0,001). Houve aumento da densidade de fibras elásticas com a progressão da idade (P < 0,001). Comparando-se as peles das pacientes de faixas etárias vizinhas, com diferença de uma década entre elas, não houve diferença significativa na quantidade de material elástico dessas peles; porém, ao se comparar aquelas com diferença de 2 ou mais décadas nas faixas etárias, o aumento foi significante (P < 0,05). A diferença do número de vasos não foi significante (P = 0,112). CONCLUSÕES: O envelhecimento promoveu redução do colágeno, degradação e fragmentação das fibras, e aumento da densidade de material elástico desorganizado, e não influenciou no número de vasos sanguíneos da derme.

BACKGROUND: In the present study, we aimed to evaluate the influence of aging on the skin quality of white-skinned women by assessing collagen levels, elastic material density, and vascularization. METHODS: Histological and morphometric analyses were performed on 218 preauricular skin fragments from white-skinned women who underwent facial cosmetic surgery. Anti-CD34 was used to identify the blood vessels, Weigert's staining was used to visualize elastic fibers, and Picro-sirius Ultra Red staining was employed for analyzing and quantifying the expression of type I, III, and total collagen. Data were analyzed according to the following donor age groups: < 40, 40-49, 50-59, 60-69, and > 70 years. RESULTS: Fragmentation and disorganization of collagen fibers were observed in certain samples, particularly in samples from patients aged > 60 years. Significant differences between age and the thickness of the dermis and epidermis were not detected. However, a relationship was identified between age and the percentages of type I, III, and total collagen, and an increase of elastic fibers density was associated with age progression (P < 0.001). The comparison of the skin of patients with a decade difference in age did not reveal a significant difference in the elastic material quality; however, when the age difference was of 2 decades or more, there was a significant difference in elastic fibers (P < 0.05). The difference in the number of blood vessels between the groups was not significant (P = 0.112). CONCLUSIONS: Aging promoted collagen reduction, fiber degradation and fragmentation, and increased disorganized elastic material density; however, it did not affect the number of dermal blood vessels.

Wound healing under the effect of iodine cadexomer in rats / Cicatrização de feridas sob efeito do cadexômero iodo em ratos

PURPOSE: To assess vthe action of iodine cadexomer in the healing process of surgical wounds in rats and if cytotoxicity occurs with the systemic absorption of iodine. METHODS: Thirty six Wistar rats were used and performed 53 wounds with surgical punch of 6 mm diameter on them. Two lesions were made diametrically opposed on groups with distilled water (GAD) and sodium chloride (GCS); on the right lesions were used bandage with distilled water and on the left ones dressing with sodium chloride. In cadexomer iodine (GCI) group, a punch injury was made only on the left side and the dressing was carried out with cadexomer iodine. The groups were divided in two sub-groups according to the day of death (7 and 14). Microscopically was used H&E staining, through which the inflammation could be observed and also the neovascularization. Staining with Masson trichrome studied fibrosis. TSH and free T4 were used for absorption recognition of iodine, and its toxic potential was performed before death with the animal anesthetized. RESULTS: Microscopic analysis showed more marked intensity of inflammation in group GAD, subgroup 14 days. Neovascularization showed be discrete in GCS sub-group 14 days. Fibrosis was more pronounced in the group GCI. Comparing the types of treatment, there was statistical significance between groups GCI and GCS (p<0.013). The TSH and T4, showed no difference between the control group and GCI in relation to the absorption of iodine. In evaluating the GCI and control groups, within each treatment, statistical significance was found between them (p<0.001) when compared the days of observation. CONCLUSION: Cadexomer iodine had beneficial effects in all phases of the healing process without cytotoxicity due iodine absorption.

OBJETIVO: Avaliar a ação do cadexômero iodo na cicatrização de feridas cirúrgicas em ratos e se ocorre citotoxicidade com a absorção sistêmica do iodo. MÉTODOS: Utilizou-se 36 ratos Wistar nos quais realizaram-se 53 feridas cirúrgicas com punch de 6 mm de diâmetro. Foram confeccionados duas lesões diametralmente opostas nos animais dos grupos água destilada (GAD) e cloreto de sódio (GCS). Na lesão do lado direito foi utilizado curativo com água destilada e, na do esquerdo, curativo com cloreto de sódio. No grupo cadexômero iodo (GCI), foi feita apenas uma lesão com o punch no lado esquerdo e o curativo foi realizado com cadexômero iodo. Os grupos foram divididos em dois subgrupos conforme o dia da morte (7 e 14). Microscopicamente foi utilizada a coloração H&E, através da qual foi observado o processo inflamatório e a neovascularização. Com a coloração tricômio de Masson foi estudada a fibrose. Para o reconhecimento da absorção do iodo e o seu potencial tóxico foi realizado, antes da morte com o animal anestesiado, dosagem do TSH e do T4 livre. RESULTADOS: Na análise microscópica a intensidade da inflamação apresentou-se mais acentuada no grupo GAD, subgrupo 14 dias. Na análise da neovascularização ela apresentou-se discreta no GCS subgrupo 14 dias. Na avaliação da fibrose foi mais acentuada no grupo GCI. Na comparação nos tipos de tratamento houve significância estatística entre os grupos GCI e GCS (p<0,013). A dosagem do TSH e T4, não apresentou diferença entre o grupo controle e GCI em relação à absorção do iodo. Na avaliação dos grupos GCI e controle, dentro de cada tratamento, houve significância estatística entre eles (p<0,001), quando comparados os dias. CONCLUSÃO: O cadexômero iodo apresentou efeito benéfico em todas as fases do processo cicatricial sem citotoxicidade pela absorção do iodo.

Influence of aging on the quality of the skin of white women: the role of collagen / Influência do envelhecimento na qualidade da pele de mulheres brancas: o papel do colágeno

PURPOSE: Evaluate the influence of aging on the quality of the skin of white women, analyzing the dermal collagen. METHODS: Pre-auricular flaps were collected for histological and morphometric analysis of 218 white women who underwent spontaneous facial aesthetic plastic surgery. Picrosirius ultrared stain was used for analysis and quantification of collagen in five age groups (<40 years, 40 to 49 years, 50 to 59 years, 60 to 69 years and 70 to 79 years) . RESULTS: Histological analysis showed changes suggestive of skin aging (fragmentation and disorganization of collagen fibers), especially in patients over 60 years. There were no significant changes in the relationship of age with the thickness of the dermis and epidermis, but there was with the percentage of the collagen I, III and total (p<0.001), which decreased with increasing aging. CONCLUSION: There is reduction in collagen with increasing age, and an increase in its degradation, leading to fragmentation of the fibers.

OBJETIVO: Avaliar a influência do envelhecimento na qualidade da pele de mulheres brancas analisando o colágeno dérmico. MÉTODOS: Realizou-se análise histológica e morfométrica de 218 retalhos pré-auriculares de mulheres brancas que se submeteram espontaneamente à cirurgia estética facial. Foi usada a coloração de Picrosirius Ultrared para analisar e quantificar os colágenos I, III e total em cinco grupos etários (<40 anos, 40 a 49 anos, 50 a 59 anos, 60 a 69 anos e 70 a 79 anos). RESULTADOS: A análise histológica mostrou alterações sugestivas de envelhecimento cutâneo (fragmentação e desorganização das fibras de colágeno), especialmente em pacientes acima de 60 anos. Não houve diferenças significantes entre a idade e a espessura da derme e da epiderme, mas houve diferenças significantes entre as percentagens de colágeno I, III e total (p<0,001) com o aumento da idade. CONCLUSÃO: Existe redução do colágeno com o aumento da idade e um aumento na sua degradação, levando à fragmentação das fibras.

Influence of arterial hypertension on colonic healing in rats / Influência da hipertensão arterial na cicatrização colônica em ratos

PURPOSE: Evaluation of colonic healing in spontaneously hypertensive rats. METHODS: Fifty male, young and inbred rats were used. Twenty-five Wistar Kyoto rats (WKY) as control and twenty-five spontaneously hypertensive rats (SHR) as an experimental group. Colotomy and bowel suture at 2.5 cm from the peritoneal reflection were performed. All animals were allocated randomly into sub-groups for review at the third, seventh and fourteenth days after surgery. We evaluated the concentration of angiotensin II, the burst pressure, epithelialization, the organization of the tunics of the bowel wall, inflammatory response and collagen deposition. RESULTS: The burst pressure, epithelialization, organization of the tunics and collagen deposition was not significant between groups. The inflammatory reaction was more intense in the control group on the third postoperative day (p=0.023) as the experimental group on the remaining time. CONCLUSION: Systemic arterial hypertension in rats did not influence significantly the healing process of colonic anastomoses.

OBJETIVO: Avaliar a cicatrização colônica em ratos espontaneamente hipertensos. MÉTODOS: Cinquenta ratos machos, jovens e isogênicos. Vinte e cinco ratos da linhagem Wistar Kyoto (WKY) como controle e vinte e cinco ratos espontaneamente hipertensos (SHR) como grupo experimento. Realizou-se colotomia e colorrafia a 2,5 cm da reflexão peritoneal. Alocaram-se os animais aleatoriamente em sub-grupos para avaliação no terceiro, sétimo e décimo quarto dias de pós-operatório. Foram avaliados a concentração de angiotensina II, a resistência da anastomose à insuflação, a epitelização, a organização das túnicas da parede intestinal, a reação inflamatória e a deposição de colágeno. RESULTADOS: A avaliação da resistência da anastomose, epitelização, organização das túnicas e deposição de colágeno não foi significativa entre os grupos. A reação inflamatória foi mais intensa no grupo controle na avaliação do terceiro dia de pós-operatório (p=0,023) igualando-se ao grupo experimento nos demais tempos. CONCLUSÃO: A hipertensão arterial sistêmica, em ratos, não influenciou de forma significante no processo cicatricial de anastomoses do cólon.

Impact of hypertension in liver regeneration in rats / Repercussão da hipertensão arterial na regeneração hepática em ratos

PURPOSE: To determine the impact of hypertension in liver regeneration, in rats by examining gain in liver mass and the replication of hepatocytes and stellate cells. METHODS: Forty Wistar rats were allocated into two groups of twenty, the control and experiment group. The experiment group animals were submitted to induction of renovascular hypertension. A week later, all the animals underwent a partial hepatectomy. Measurements were taken after 24 hours and seven days, when ten animals in each group were euthanized. Thus, four subgroups were obtained. The livers were excised and sent for histopathological analysis. RESULTS: The control group had a greater gain in liver mass than the experiment group seven days after partial hepatectomy (p=0.0051). The difference in the activate stellate cell count was not statistically significant following analysis after both 24 hours and seven days (p=1.0). A higher number of dividing hepatocytes was observed in the control group seven days after partial hepatectomy (p=0.0014). CONCLUSION: In rats, hypertension had no direct influence on stellate cell replication, but led to a delay in liver mass gain and were shown to be a reduction factor on hepatocyte replication seven7 days after partial hepatectomy.

OBJETIVO: Determinar o impacto da hipertensão arterial sistêmica na regeneração hepática, em ratos, através da análise do ganho de massa hepática e da replicação dos hepatócitos e das células estreladas. MÉTODOS: Alocaram-se 40 ratos Wistar em dois grupos de 20 animais, os grupos controle e experimento. Os do grupo experimento submeteram-se a indução da hipertensão renovascular. Uma semana após, realizou-se hepatectomia parcial em todos os animais. Colheram-se os dados com 24 horas e sete dias, quando dez animais de cada grupo submeteram-se a eutanásia. Assim, obtiveram-se quatro subgrupos. Os fígados foram retirados e enviados para análise histopatológica. RESULTADOS: O grupo controle apresentou maior ganho de massa hepática do que o grupo experimento sete dias após a hepatectomia parcial (p=0,0051). A diferença na contagem das células estreladas ativadas não foi estatisticamente significante nas análises de 24 horas e de sete dias (p=1,0). Um maior número de hepatócitos em divisão foi observado no grupo controle, sete dias após a hepatectomia parcial (p=0,0014). CONCLUSÃO: Em ratos, a hipertensão não teve influência direta sobre a replicação de células estreladas, mas levou ao atraso no ganho de massa hepática e mostrou ser um fator de redução na replicação de hepatócitos sete dias após a hepatectomia parcial.

Rede hemostática: uma alternativa para a prevenção de hematoma em ritidoplastia / Hemostatic net: an alternative for the prevention of hematoma in rhytidoplasty

INTRODUÇÃO: Hematoma é a complicação pós-operatória mais frequente em ritidoplastia. Sua ocorrência aumenta a morbidade e prejudica a recuperação. Pontos de adesão internos para fechamento das áreas descoladas em abdominoplastias evitam o surgimento de seroma. Baseados neste princípio, e com o objetivo de reduzir o número de pacientes com hematomas em ritidoplastia, foi desenvolvida tática cirúrgica análoga em que se confecciona uma rede hemostática de pontos contínuos e transfixantes de náilon 4-0, englobando a pele e o SMAS-platisma. MÉTODO: Foram incluídos no estudo 366 pacientes consecutivos, submetidos a ritidoplastia de pelo menos o terço médio da face, entre julho de 2009 e setembro de 2011. O grupo A, incluindo os primeiros 120 pacientes avaliados retrospectivamente, foi considerado controle. O grupo B foi constituído pelos demais 246 pacientes, operados com a tática cirúrgica proposta e avaliados prospectivamente. Observaram-se as incidências de hematoma, isquemia e necrose nas primeiras 72 horas de pós-operatório. RESULTADOS: No grupo A, 17 (14,2%) pacientes apresentaram hematoma, enquanto no grupo B não houve nenhum caso. A tática cirúrgica não aumentou significativamente a ocorrência de isquemia: 11 (9,2%) pacientes no grupo A e 16 (6,5%) no grupo B tiveram essa complicação (P < 0,3964). Também não houve alteração significativa na incidência de necrose, complicação observada em 3 (2,5%) pacientes do grupo A e em 4 (1,6%) do grupo B (P < 0,4298). CONCLUSÕES: A rede hemostática é método eficaz na prevenção de hematomas precoces em ritidoplastias. Essa tática cirúrgica não levou a aumento significativo da incidência de isquemia e necrose.

BACKGROUND: Hematoma is the most common postoperative complication of rhytidoplasty. Its occurrence increases morbidity and impairs recovery. Internal sutures to close detached areas are used in abdominoplasty to prevent seromas. Taking this into account and in order to reduce the number of patients with hematomas post rhytidoplasty, we have developed a similar surgical procedure in which a hemostatic net is made of continuous nylon 4-0 transfixing stitches to include the skin and the superficial musculoaponeurotic system-platysma. METHODS: A total of 366 patients who underwent rhytidoplasty of at least the middle third of the face between July 2009 and September 2011 were included in the study. Group A was identified as the control group; it included the first 120 patients assessed retrospectively. The remaining 246 patients, who underwent the surgical procedure here proposed and who were evaluated prospectively formed group B. We observed the incidence of hematoma, ischemia, and necrosis in the first 72 postoperative hours. RESULTS: In group A, 17 (14.2%) patients developed hematomas, whereas none occurred in group B. The surgical procedure did not significantly increase the occurrence of ischemia: 11 (9.2%) patients in group A and 16 (6.5%) in group B had this complication (P < 0.3964). There was also no significant increase in the incidence of necrosis, which was observed in 3 (2.5%) patients in group A and 4 (1.6%) in group B (P < 0.4298). CONCLUSIONS: The hemostatic net is an efficient method for the prevention of early hematomas following rhytidoplasty. This surgical procedure did not result in a significant increase in the incidence of ischemia and necrosis.

Cicatrização da parede abdominal após hepatectomia parcial / Healing of the abdominal wall after parcial hepatectomy

OBJETIVO: Avaliar a cicatrização da ferida incisional da parede abdominal de ratos hepatectomizados quanto à concentração de colágeno, reação inflamatória e angiogênese. MÉTODOS: Utilizaram-se 48 ratos distribuídos aleatoriamente para laparotomia com e sem hepatectomia. As cicatrizes foram estudadas no 3º, 7º e 14º dia de pós-operatório. Analisou-se a densidade do colágeno por método histoquímico e a angiogênese por método imunohistoquímico. RESULTADOS: A análise do colágeno total mostrou menor concentração no plano da pele e da tela subcutânea, nas cicatrizes abdominais do grupo experimento (p3=0,011; p7=0,004 e p14=0,008). A densidade de colágeno I foi inferior no grupo hepatectomizado, principalmente no 3º dia, tanto na pele e tela subcutânea (p=0,038) quanto no plano aponeurótico (p=0,026). Houve menor concentração de colágeno III nos dois planos estudados, embora não significante. A resposta inflamatória foi semelhante em todos os tempos, nos dois grupos. Verificou-se que a angiogênese desenvolveu-se mais precocemente no grupo controle (p3=0,005 e p7=0,012) e mais tardiamente no grupo experimento (p14=0,048). CONCLUSÃO: A hepatectomia leva ao atraso do processo cicatricial, interferindo na síntese do colágeno e na angiogênese.

OBJECTIVE: To evaluate the wound healing of the abdominal wall incision in hepatectomized rats as for the concentration of collagen, inflammatory reaction and angiogenesis. METHODS: We used 48 rats randomly assigned to laparotomy with or without hepatectomy. The scars were studied in the 3rd, 7th and 14th postoperative days. We analyzed the density of collagen by the histochemical method and angiogenesis, by immunohistochemistry. RESULTS: The analysis showed a lower total collagen concentration in skin and subcutaneous tissue in the abdominal scars of the experiment group (p3 = 0.011, p7 = 0.004 and p14 = 0.008). The density of collagen I was lower in the hepatectomy group, especially in the third day, in the skin, subcutaneous tissue (p = 0.038) and in the aponeurotic plane (p = 0.026). There was a lower concentration of collagen III in the two abdominal wall layers studied, although not statistically significant. The inflammatory response was similar at all times in both groups. It was found that angiogenesis was developed earlier in the control group (p3 = 0.005 and p7 = 0.012) and later in the experimental group (p14 = 0.048). CONCLUSION: Hepatectomy leads to a delay in the healing process, interfering with collagen synthesis and angiogenesis.

Avaliação do uso tópico do metronidazol no processo de cicatrização de feridas: um estudo experimental / Evaluation of topical metronidazole in the healing wounds process: an experimental study

OBJETIVO: Avaliar a ação do metronidazol em solução a 4 por cento, tópico, em feridas com cicatrização por segunda intenção em ratos. MÉTODOS: Fez-se feridas circulares com dois centímetros de diâmetro no dorso de ratos e estudou-se a cicatrização em 3, 7, 14 e 21 dias. A contração da ferida e a epitelização periférica foram avaliadas por planimetria digital e os miofibroblastos pela imunoistoquímica com a-SMA. RESULTADOS: Não houve diferença entre os grupos em relação à contração ferida. Nas feridas tratadas com metronidazol a epitelização periférica precoce foi evidente no 3°dia (p<0,001) e não houve diferenças nos demais períodos. No grupo controle, o número de miofibroblastos foi maior no 7° dia (p=0,003) e no 14° dia (p=0,001), e no grupo experimento, foi sugestivamente maior no 3° dia (p=0,06). CONCLUSÃO: O metronidazol, solução a 4 por cento, na dose de 50mg/kg/dia, aplicado de forma tópica nas feridas com cicatrização por segunda intenção, facilita a epitelização periférica precoce, não interfere na contração da ferida e atrasa o aparecimento dos miofibroblastos.

OBJECTIVE: To assess the efficacy of topical a 4 percent metronidazole solution in wounds healing by secondary intention in rats. METHODS: We made circular wounds two inches in diameter at the back of rats and studied healing at 3, 7, 14 and 21 days. The wound contraction and epithelialization were assessed by peripheral digital planimetry and myofibroblasts by immunohistochemistry with a-SMA. RESULTS: There was no difference between groups regarding wound contraction. In wounds treated with metronidazole peripheral epithelialization was evident early on day 3 (p <0.001) and there were no differences in other periods. In the control group, the number of myofibroblasts was higher on day 7 (p = 0.003) and day 14 (p = 0.001) and in the experimental group it was suggestively higher on day 3 (p = 0.06). CONCLUSION: Metronidazole 4 percent solution at a dose of 50 mg/kg applied topically to wounds healing by secondary intention facilitates early peripheral epithelialization, does not interfere with wound contraction and delays the appearance of myofibroblasts.