Small intestinal submucosa as a graft to increase rectum diameter.

BACKGROUND: The purpose of our study was to assess the biocompatibility of the porcine small bowel submucosa and its ability to increase the rectal diameter compared with a formal transverse coloplasty. METHODS: We assigned 36 New Zealand male rabbits to four experimental groups: groups C1 and C2 were treated with transverse coloplasty and groups S1 and S2 were treated with a patch of a porcine small intestine submucosa. We killed the animals in the C1 and S1 groups on the 7th postoperative day, and the animals in the C2 and S2 groups on the 30th postoperative day. We evaluated outcomes on the basis of animal survival, clinical course, anastomosis bursting pressures, morphometric examination, and histologic and immunohistochemical assessment. RESULTS: Morphometric examination showed a significant increase in colonic diameter in animals in the S2 group. We found no statistical difference regarding anastomosis bursting pressure between the C1 and S1 groups, and the C2 and S2 groups. On the 30th postoperative day, histologic examination showed total epithelium coverage of the grafts, and the immunohistochemical study showed an organized smooth muscular layer covering the graft. The higher concentration of collagen ticker fiber, type I, was seen in the S2 and C2 groups, but there was no statistical difference between them. CONCLUSIONS: The implanted graft proved superior to transverse coloplasty regarding the increase in distal colon diameter. Remarkable regeneration, marked fibroplasia, and epithelium coverage occurred throughout the graft on the 30th postoperative day.

[Aberrant crypt foci and cancer of the colorectal junction: the correlation between beta-catenin/Ki-67 expression and the occurrence of early microscopic secondary lesions surrounding periphery colorectal cancer]. / Foco de criptas aberrantes e câncer da junção colorretal: análise da presença de lesões precoces microscópicas na periferia do câncer colorretal e correlação com a expressão da beta-catenina e Ki-67.

OBJECTIVE: To evaluate the occurrence of aberrant crypt foci (ACF) in macroscopic normal mucosa surrounding colorectal cancers (CRC); additionally, analyze tumor progression from ACF to CRC by means of beta-catenin and Ki-67 expression. METHODS: Twenty-one surgical specimens showing colorectal junction adenocarcinoma were included. Macroscopic normal mucosa proximal and distal to the primary tumor was sampled at a distance of 1 and 5 cm in both sides. A primary tumor sample was also retrieved. Eventually, ACF's were selected and immunohistochemical analysis of beta-catenin and Ki-67 were carried out. RESULTS: Among all adenocarcinoma samples, the frequency of positive â-catenin nuclear expression was 81%. The Ki-67 expression demonstrated the same percentage of positivity as did beta-catenin. However, the Kappa coefficient showed weak relationship between those two antibodies. Among 20 ACF's analyzed, 13 were located close (1 cm) to the tumor. None of the ACF's demonstrated nuclear expression of beta-catenin or Ki-67. CONCLUSION: Higher concentrations of ACF's were observed in colonic mucosa at a distance of 1 cm compared to samples at 5 cm from the primary CRC. However, we could not demonstrate positive correlation between colonocytes beta-catenin expression and the occurrence of ACF's.

Foco de criptas aberrantes e câncer da junção colorretal: análise da presença de lesões precoces microscópicas na periferia do câncer colorretal e correlação com a expressão da β-catenina e Ki-67 / Aberrant crypt foci and cancer of the colorectal junction: the correlation between β-catenin/Ki-67 expression and the occurrence of early microscopic secondary lesions surrounding periphery colorectal cancer

OBJETIVO: Avaliar a presença de foco de criptas aberrantes (FCA) em mucosa macroscopicamente normal, localizada na periferia de um câncer colorretal (CCR) e correlacionar a progressão tumoral destes FCA para o CCR, por meio da expressão da β-catenina e o Ki-67. MÉTODOS: Utilizou-se 21 espécimes cirúrgicos contendo adenocarcinoma de junção retossigmóide. Foram coletadas amostras localizadas a 1 e 5 cm proximal e distal ao tumor, quando possível, bem como um fragmento da neoplasia. Os FCA foram selecionados. Subseqüentemente foi realizado estudo imunoistoquímico com os anticorpos β-catenina e o Ki-67. RESULTADOS: A expressão nuclear da β-catenina nos adenocarcinomas, revelou freqüência de 81 por cento. O Ki-67 apresentou a mesma freqüência. Apesar disso o coeficiente Kappa revelou fraca concordância entre estes anticorpos. Foram observados 20 FCA, sendo que 13 destes focos localizavam-se nas proximidades do tumor. Nenhum dos FCA apresentou expressão da β-catenina nuclear, tampouco para o Ki-67. CONCLUSÃO: Nas áreas situadas a 1 cm da neoplasia colorretal, foi observada maior concentração de FCA em relação às áreas situadas a 5 cm do tumor. No entanto, não se observou correlação entre a expressão da β-catenina e ki-67 nos colonócitos das criptas aberrantes das áreas estudadas, com as células neoplásicas do adenocarcinoma.

OBJECTIVE: To evaluate the occurrence of aberrant crypt foci (ACF) in macroscopic normal mucosa surrounding colorectal cancers (CRC); additionally, analyze tumor progression from ACF to CRC by means of β-catenin and Ki-67 expression. METHODS: Twenty-one surgical specimens showing colorectal junction adenocarcinoma were included. Macroscopic normal mucosa proximal and distal to the primary tumor was sampled at a distance of 1 and 5 cm in both sides. A primary tumor sample was also retrieved. Eventually, ACF's were selected and immunohistochemical analysis of β-catenin and Ki-67 were carried out. RESULTS: Among all adenocarcinoma samples, the frequency of positive â-catenin nuclear expression was 81 percent. The Ki-67 expression demonstrated the same percentage of positivity as did β-catenin. However, the Kappa coefficient showed weak relationship between those two antibodies. Among 20 ACF's analyzed, 13 were located close (1 cm) to the tumor. None of the ACF's demonstrated nuclear expression of β-catenin or Ki-67. CONCLUSION: Higher concentrations of ACF's were observed in colonic mucosa at a distance of 1 cm compared to samples at 5 cm from the primary CRC. However, we could not demonstrate positive correlation between colonocytes β-catenin expression and the occurrence of ACF's.

The influence of methylene blue on the healing of intestinal anastomoses subjected to ischemia and reperfusion in rats.

PURPOSE: To investigate the influence of methylene blue, on the healing of intestinal anastomoses subjected to ischemia and reperfusion in rats. METHODS: Forty-five rats divided into the following three groups were used: control (G1); ischemia without methylene blue (G2); and ischemia with methylene blue (G3). A laparotomy was performed and the cranial mesenteric artery isolated. Whereas the cranial artery was temporarily occluded for 45 minutes in groups G2 and G3, prior to enterotomy and intestinal anastomosis, in group G1 the enterotomy and intestinal anastomosis were performed without prior lesion. Afterwards, 2mL of 0.5% methylene blue were instilled in the peritoneal cavities of the animals in group G3, and 2mL of isotonic saline solution in the peritoneal cavities of the animals in group G2. After the reperfusion, an enterectomy and intestinal anastomosis were performed. After the animals had been sacrificed on the seventh day after the operation, the abdominal cavity was examined by resection of a segment of the intestine containing the anastomosis in order to measure its strength and for histopathological examination. RESULTS: Free fluid or abscesses in the peritoneal cavity were rare. When inflammation was analyzed, the group subjected to ischemia without methylene blue had a higher score for mononuclear cells (p=0.021) and granulation tissue (p=0.044). No significant difference was observed in the density of type I or type III collagens. CONCLUSION: The methylene blue did not show beneficial effect on the healing of intestinal anastomoses subjected to ischemia and reperfusion in rats.

The influence of methylene blue on the healing of intestinal anastomoses subjected to ischemia and reperfusion in rats / A influência do azul de metileno na cicatrização de anastomoses intestinais submetidas à isquemia e reperfusão em ratos

PURPOSE: To investigate the influence of methylene blue, on the healing of intestinal anastomoses subjected to ischemia and reperfusion in rats. METHODS: Forty-five rats divided into the following three groups were used: control (G1); ischemia without methylene blue (G2); and ischemia with methylene blue (G3). A laparotomy was performed and the cranial mesenteric artery isolated. Whereas the cranial artery was temporarily occluded for 45 minutes in groups G2 and G3, prior to enterotomy and intestinal anastomosis, in group G1 the enterotomy and intestinal anastomosis were performed without prior lesion. Afterwards, 2mL of 0.5 percent methylene blue were instilled in the peritoneal cavities of the animals in group G3, and 2mL of isotonic saline solution in the peritoneal cavities of the animals in group G2. After the reperfusion, an enterectomy and intestinal anastomosis were performed. After the animals had been sacrificed on the seventh day after the operation, the abdominal cavity was examined by resection of a segment of the intestine containing the anastomosis in order to measure its strength and for histopathological examination. RESULTS: Free fluid or abscesses in the peritoneal cavity were rare. When inflammation was analyzed, the group subjected to ischemia without methylene blue had a higher score for mononuclear cells (p=0.021) and granulation tissue (p=0.044). No significant difference was observed in the density of type I or type III collagens. CONCLUSION: The methylene blue did not show beneficial effect on the healing of intestinal anastomoses subjected to ischemia and reperfusion in rats.

OBJETIVO: Investigar a influência do azul de metileno, na cicatrização de anastomoses intestinais de ratos submetidas a isquemia e à reperfusão. MÉTODOS: Quarenta e cinco ratos foram divididos em três grupos: controle (G1); isquemia sem azul de metileno (G2) e isquemia com azul de metileno (G3). Foi feita uma laparotomia e a artéria mesentérica cranial isolada. Enquanto a artéria mesentérica cranial foi ocluída por 45 minutos nos grupos G2 e G3, antes da anastomose, no grupo G1 a anastomose foi realizada sem esta lesão prévia. Em seguida 2 mL de azul de metileno 0,5 por cento foi instilado na cavidade peritoneal dos animais do grupo G3, 2 mL de solução salina isotônica na cavidade dos animais do grupo G2. Após a reperfusão uma enterectomia seguida de anastomose foi realizada. Os animais foram submetidos à eutanásia no 7.º dia após a operação, a cavidade abdominal foi examinada e um segmento intestinal que continha a anastomose foi ressecado. Este serviu para a medida de resistência e para exame anátomo-patológico. RESULTADOS: Líquido livre ou abscessos foram raros. A análise da inflamação mostrou que o grupo submetido à isquemia sem azul de metileno apresentou maior score para células mononucleares (p=0,021) e tecido de granulação (0,044). Não se observou diferença significante na análise do colágeno I e III. CONCLUSÃO: O azul de metileno não mostrou efeitos benéficos na cicatrização de anastomoses intestinais submetidas à isquemia e à reperfusão em ratos.

The role of electroanalgesia in patients undergoing coronary artery bypass surgery.

OBJECTIVE: To assess the electroanalgesia as an effective method in the reduction of pain and consequent improvement in lung function in patients undergoing coronary artery bypass graft surgery. METHODS: During the period of one year were studied 30 patients undergoing surgery for treatment of the ischemic coronary disease. After randomization, 15 patients were allocated in the study group (that received electroanalgesia) and 15 patients from the controlled group (placebo). From the 1st until the 5th postoperative day were realized two applications of electroanalgesia or the placebo current, according the group where the patient was allocate. RESULTS: There was a reduction in the levels of pain in the study group compared to the controlled group, evidenced by the value P<0.05; however, there isn't evidence of statistical difference of the spirometric variables between them. CONCLUSION: The group that did electroanalgesia presented reduction in the intensity of postoperative pain, which however did not mean improvement in respiratory function of these patients.

Papel da eletroanalgesia na função respiratória de pacientes submetidos à operação de revascularização do miocárdio / The role of electroanalgesia in patients undergoing coronary artery bypass surgery

OBJETIVO: Avaliar a eletroanalgesia como método eficaz na diminuição da dor e consequente melhora da capacidade pulmonar em pacientes submetidos a operação de revascularização do miocárdio. MÉTODOS: No período de um ano foram estudados 30 pacientes submetidos a operação para tratamento da doença coronariana isquêmica. Após a randomização, 15 pacientes foram alocados no grupo estudo (que receberam eletroanalgesia) e 15 pacientes no grupo controle (placebo). No pré-operatório todos os doentes foram entrevistados e realizaram espirometria. Do primeiro ao quinto dia de pós-operatório foram realizadas duas aplicações diárias de eletroanalgesia ou de corrente placebo, conforme o grupo em que o paciente estivesse alocado, e no quinto dia, nova espirometria. RESULTADOS: Todos os pacientes evoluíram satisfatoriamente, sem complicações inerentes à operação de revascularização do miocárdio. Verificou-se que a cirurgia reduziu os valores espirométricos de ambos os grupos (P= 0,00). Os resultados encontrados demonstraram também redução nos níveis de dor no grupo estudo quando comparado ao grupo controle. Este por sua vez não repercutiu em melhora da função pulmonar como resultado da aplicação da TENS quando comparado ao grupo controle (P>0,05). CONCLUSÃO: O grupo que realizou eletroanalgesia apresentou redução da intensidade da dor pós-operatória o que não implicou, contudo, na melhora da função respiratória de tais pacientes

OBJECTIVE: To assess the electroanalgesia as an effective method in the reduction of pain and consequent improvement in lung function in patients undergoing coronary artery bypass graft surgery. METHODS: During the period of one year were studied 30 patients undergoing surgery for treatment of the ischemic coronary disease. After randomization, 15 patients were allocated in the study group (that received electroanalgesia) and 15 patients from the controlled group (placebo). From the 1st until the 5th postoperative day were realized two applications of eletroanalgesia or the placebo current, according the group where the patient was allocate. RESULTS: There was a reduction in the levels of pain in the study group compared to the controlled group, evidenced by the value P<0.05; however, there isn't evidence of statistical difference of the spirometric variables between them. CONCLUSION: The group that did eletroanalgesia presented reduction in the intensity of postoperative pain, which however did not mean improvement in respiratory function of these patients

Avaliação da exposição e interrupção da nicotina em tempos diferentes na evolução de retalho cutâneo ao acaso de dorso de ratos por meio de fluxometria a laser e de picrosirius / Assessment of the exposure and interruption of nicotine at different times in therats’ dorsum random cutaneous flap evolution by laser flowmetry and picrosirius

Introdução: Os benefícios da interrupção do tabagismo previamente à cirurgia ainda nãoestão bem definidos. Objetivo: Avaliar a influência da interrupção da nicotina em um retalhocutâneo, por meio da fluxometria a laser e com picrosirius. Método: Foram utilizados 56 ratos,divididos em grupos expostos à nicotina 2mg/kg/dia, e a 0,5mg/kg/dia, e somente à soluçãosalina. Os animais foram subdivididos de acordo com o tempo de exposição, em 1 e 2 semanasde interrupção previamente à cirurgia e tratamento ininterrupto até 10 dias do pós-operatório.Após o 10º dia, foram avaliados os retalhos cutâneos do dorso do animal, por meio defluxometria a laser, formação de colágeno, e diferenciação em maduro e imaturo, pelopicrosirius. Resultados: A fluxometria foi maior no controle e nos grupos de baixas doses.A interrupção da droga mostrou aumento da fluxometria somente nos grupos de baixa dose.A proporção de colágeno maduro para imaturo foi inversamente proporcional à dose e aotempo de exposição à droga. Conclusões: A nicotina prejudica a evolução de um retalhocutâneo do dorso de ratos, sendo dependente da dose. O tempo de interrupção altera afluxometria e a proporção de formação de colágeno, quando dada em baixa dose.

Introduction: The benefits of the interruption of the tabagism previously the surgery not yet wellare defined. Objective: The objective of this study was to assess the influence of the interruptionof exposure to nicotine on a cutaneous flap, by laser flowmetry and picrosirius. Method: 56 rats wereused, divided in groups and administred nicotine 2mg/kg/day, 0,5mg/kg/day and just saline solution.Animals were subdivided according to exposure time to the drug, that is, in one and two weeks’interruption prior to surgery, and constant treatment up to ten days after surgical procedure. Theywere organized in seven groups. A cutaneous flap was performed on the animals’ dorsum and onthe tenth day of PO the laser flow measurement and the formation of collagen and its differentiationin mature and immature by picrosirius. Results: The flowmetry was bigger in the control and thegroups of low doses. The interruption of the drug only showed increase of the flowmetry in thegroups of low dose. The ratio of mature colageno for immature was inversely proportional to the doseand the time of exposition to the drug. Conclusion: The nicotine harms the evolution of a remnantcutaneous of the back of rats, being dependent of the dose. The interruption time modifies theflowmetry and the ratio of formation of colageno, when given in low dose.

The protective effect of methylene blue in lungs, small bowel and kidney after intestinal ischemia and reperfusion.

PURPOSE: To study the role of methylene blue as an inhibitor of superoxide production by xanthine oxidase. METHODS: Thirty-two Wistar rats were divided into 2 groups of 16 animals: the control group and the experimental group. All were submitted to a laparotomy for the occlusion of the cranial mesenteric artery during 60 minutes. The reperfusion was confirmed by the pulsation of the artery after the release of the temporary ligature and color change of the intestines. In the animals of the control group, 2 ml of saline were injected in the peritoneal cavity and in the animals of the experimental group, 2 ml of methylene blue were injected in the peritoneal cavity. After reperfusion for 4 hours, the animals were then sacrificed. The lungs were excised from all 32 rats. Simultaneously, the small intestine and kidneys were ressected in 20 animals (10 from the control group and 10 from the experimental group). Samples of the organs were taken to evaluate the action of xanthine-oxidase, for histopathology studies and for characterization of the edema. RESULTS: In the animals of the experimental group, the inflammatory lesion as well as the edema in the lung was greater than in the control group. The intestinal and renal lesions were similar in both groups, but the lung damage was superior to that observed in the intestines and kidneys. . CONCLUSION: Despite similar action of the xanthine oxidase in the control and the experimental group, after intestinal ischemia and reperfusion, the protective effect of methylene blue was observed only in the lungs of the experimental group.

The protective effect of methylene blue in lungs, small bowel and kidney after intestinal ischemia and reperfusion

PURPOSE: To study the role of methylene blue as an inhibitor of superoxide production by xanthine oxidase. METHODS: Thirty-two Wistar rats were divided into 2 groups of 16 animals: the control group and the experimental group. All were submitted to a laparotomy for the occlusion of the cranial mesenteric artery during 60 minutes. The reperfusion was confirmed by the pulsation of the artery after the release of the temporary ligature and color change of the intestines. In the animals of the control group, 2 ml of saline were injected in the peritoneal cavity and in the animals of the experimental group, 2 ml of methylene blue were injected in the peritoneal cavity. After reperfusion for 4 hours, the animals were then sacrificed. The lungs were excised from all 32 rats. Simultaneously, the small intestine and kidneys were ressected in 20 animals (10 from the control group and 10 from the experimental group). Samples of the organs were taken to evaluate the action of xanthine-oxidase, for histopathology studies and for characterization of the edema. RESULTS: In the animals of the experimental group, the inflammatory lesion as well as the edema in the lung was greater than in the control group. The intestinal and renal lesions were similar in both groups, but the lung damage was superior to that observed in the intestines and kidneys. . CONCLUSION: Despite similar action of the xanthine oxidase in the control and the experimental group, after intestinal ischemia and reperfusion, the protective effect of methylene blue was observed only in the lungs of the experimental group.

OBJETIVO: Estudar a ação do azul de metileno como supressor da produção de radicais livres de oxigênio, atuando como receptor alternativo de elétrons na enzima xantina-oxidase. MATERIAIS E MÉTODOS: Foram utilizados 32 ratos Wistar (Rattus norvegicus albinus, Rodentia mammalia) divididos em 2 grupos de 16 animais, os quais foram denominados grupos: experimento e controle. Todos os animais foram submetidos a laparotomia mediana e oclusão da artéria mesentérica cranial por 60 minutos. A reperfusão foi confirmada por meio da verificação do reaparecimento da pulsação da arcada mesentérica. Foi então administrado no grupo experimento 2 ml de azul de metileno 1 por cento intra-peritonealmente, enquanto que no grupo controle o mesmo volume de solução salina isotônica foi administrado pela mesma via. Após 4 horas de reperfusão, os animais foram sacrificados. Os pulmões foram ressecados nos 32 animais do estudo, ao passo que o intestino delgado e os rins em 20 animais (10 ratos do grupo controle e 10 ratos do grupo experimento). Amostras dos órgãos retirados foram obtidas para medição da xantina-oxidase, análise histopatológica e avaliação do edema. RESULTADOS: O dano pulmonar encontrado no grupo controle foi superior ao encontrado no grupo experimento. Observou-se uma maior formação de edema e uma maior atividade inflamatória nos pulmões do grupo controle. O dano intestinal e renal encontrado foi semelhante em ambos os grupos, mas não tão intenso quanto o dano pulmonar. A atividade da xantina-oxidase foi semelhante em ambos os grupos. CONCLUSÃO: A atividade protetora do azul de metileno foi evidenciada nos pulmões, todavia o mesmo efeito não foi demonstrado nos rins nem no intestino delgado.

Effects of venous supercharging in deep inferior epigastric artery perforator flap

PURPOSE: To evaluate the effects of venous supercharging in deep inferior epigastric artery perforator flap in rats. METHODS: 20 Wistar rats were randomized in 2 groups: control group (C), all had flaps raised based on the deep inferior epigastric perforator vessels (DIEP), and experimental group (E), which was identical to group C, except that the contralateral superficial inferior epigastric vein was also kept with the flap. Flow studies using laser Doppler flowmetry where performed daily in the four zones of the flap. On the 7th postoperative day rats were killed and flap survival was determined using digital planimetry. RESULTS: Flow values were presented as a percentage of the baseline flow after incision of the flap edges. The surviving flap area was demonstrated as a percentage of the total flap area. Evaluation by digital planimetry showed that flap survival in group E was higher than in group C (97,38 percent±1,32 percentvs.44,13 percent±4,83 percent, p=0,0006). CONCLUSION: This study shows that venous supercharging of the rat DIEP flap results in greater flap survival.

OBJETIVO: Avaliar o efeito da vascularização venosa ampliada na viabilidade do retalho perfurante da artéria epigástrica profunda em ratos. MÉTODOS: Vinte ratos foram divididos em 2 grupos: controle(C), no qual se realizou o retalho perfurante da artéria epigástrica profunda e experimento(E), no qual se realizou o mesmo retalho e se manteve a veia epigástrica superficial inferior contralateral ao pedículo. Foi realizada determinação diária do fluxo sanguíneo por fluxometria por laser-doppler em quatro quadrantes do retalho previamente estabelecidos e a viabilidade foi determinada, no 7º pós-operatório, através de planimetria. RESULTADOS: A análise do fluxo sangüíneo demonstrou não haver diferença entre o grupo C e E nas médias de fluxo entre as zonas do retalho (Zona I:103,44±8,09vs.84,70±7,98, p=0,114)(Zona II: 109,18±6,99 vs. 113,67±26,89, p=0,401)(Zona III: 89,15±11,11 vs. 106,79±15,93, p=0,599)(Zona IV: 104,43±11,50 vs. 124,90±23,17, p=1,00). A viabilidade do grupo E foi superior do que no grupo C quando determinada por planimetria digital (97,38 por cento±1,32 por cento vs. 44,13 por cento±4,83 por cento, p=0,0006). CONCLUSÃO: Há aumento da viabilidade do retalho DIEP submetidos à supercharging.

Interleukin-6 (IL-6) influence on colonic anastomosis healing in rats

PURPOSE:To observe the effect of pro-inflamatory citokin, Interleukin-6 (IL-6), administration on the healing of colonic anastomosis in rats. METHODS: Thirty Wistar rats were divided into 2 groups of 15 animals each: a control group and an experiment group. The animals of the experiment group were submitted to injection of 500æg/kg of IL-6 Recombinant (Sandoz Phamarceutical®) subcutaneously 24 and 12 hours preceding the surgery, and the control group, were submitted to the injection of saline solution, using the same volume of solution as well as the way of administration. The rats were submitted to an end to end colonic anastomosis, being sacrificed in the 7th post-operative day, the site of the anastomosis was evaluated regarding to the adhesions that was quantified and the presence of complications was observed. The colon containing the anastomosis was submitted to a tensiometric study and a sample were sent for histological studies with HE and Sirius Red dye. RESULTS: The macroscopic and the tensiometric study did not demonstrate any significant differences between the control and experiment group. Regarding the histological evaluation, there was a significant reduction of the chronic inflammatory process in the experiment group (p=0,0209) and a lesser granulation area (p=0,0099). The total amount of collagen was similar in both groups, however, the experimental group showed a predominant area of immature collagen (p=0.009). CONCLUSIONS: The longer persistence of the acute phase of wound healing in the experiment group, as well as a decreased of the mature collagen type I, demonstrating that the IL-6 was harmful to the colonic healing anastomosis in rats.

OBJETIVO: Verificar a influência da administração da citocina pró-inflamatória, Interleucina-6 (IL-6), na cicatrização de anastomoses colônicas em ratos. MÉTODOS: Utilizaram-se 30 ratos Wistar, divididos em 2 grupos, controle e experimento, de 15 animais cada. Os animais do grupo experimento receberam nas 24 e 12 horas precedentes a cirurgia, 500æg/kg de IL-6 Recombinante (Sandoz Phamarceutical®) via subcutâneo, os animais do grupo controle, receberam a administração de soro fisiológico nesse mesmo período, pela mesma via. Foram submetidos à anastomose colônica término-terminal. No 7° dia pós-operatório foram realizadas a eutanásia, com quantificação macroscópica das aderências e visualização de complicações. Em seguida realizou-se o estudo tensiométrico, seguido do estudo histológico das lâminas coradas com Hematoxicilina Eosina e Sirius Red. RESULTADOS: O estudo macroscópico e tensiométrico não demonstraram diferenças significativas entre os grupos estudados. Na avaliação histológica, os resultados significativos demonstraram uma diminuição no grupo experimento do processo inflamatório crônico (p=0,0209) e uma menor área de granulação (p=0,0099) presente neste grupo. Na densitometria do colágeno houve um percentual significativamente maior de colágeno imaturo (tipo III) no grupo experimento (70,76 +-9,47), quando comparado ao grupo controle (56,31 +-11,29), p= 0,009. CONCLUSÕES: Os resultados analisados mostraram que houve um maior número de complicações relacionados à persistência da fase aguda da cicatrização no grupo experimento, com manutenção do processo inflamatório agudo neste grupo e que a Interleucina-6, mostrou-se ser prejudicial à cicatrização de anastomoses colônicas em ratos.

Abdominal wall healing in reoperated rats

PURPOSE: Experimental evaluation of the abdominal wall healing in reoperations on the same surgical site, by means of macroscopic analysis, histological and breaking strength studies of the surgical scar. METHODS: Twenty-four rats were selected and divided in 3 groups (G1, G2 and G3). A medium longitudinal laparotomy was performed, followed by laparorrhaphy on two synthesis planes, using an interrupted suture technique. The reoperations were performed in the same way, on the same surgical site. On the first day of the study all the 24 rats were operated, on the 30th day the 16 animals belonging to G2 and G3 were reoperated, and finally, on the 60th day, the 8 rats from G3 were operated for the third and last time. After 30 days of the last laparotomy of each group, euthanasia was performed. Complications such as adhesions were evaluated during the resection of surgical site. The breaking strength study was performed next, followed by the microscopical collagen analysis, using for that histological cuts stained with picrosirius. RESULTS: The adhesions were prevalent in G2 and G3 (16 percent each) when compared to G1. No significant difference was found in the breaking strength study. Statistically significant difference was observed in collagen concentration analysis. It was found higher mature collagen (type I) as well as total collagen concentration in the groups operated more than once (G2 and G3). The highest concentration of mature collagen (p<0,0001) and total collagen (p<0,0021) were found in G3 followed by G2 and G1 (in this sequence). CONCLUSION: The highest mature collagen concentration on the experimental groups, points out the importance of inflammatory activity in the healing process; in the resutures of the abdominal wall the surgical scar maturity is faster acquired than in the primary sutures; in relation to the primary sutures, the resutures of the abdominal wall did not influence in the resistance of the surgical scar.

OBJETIVO: Avaliar experimentalmente o processo cicatricial da parede abdominal após reoperações realizadas com o mesmo acesso cirúrgico, por meio da análise macroscópica e do estudo das características histopatológicas e tensiométricas da cicatriz cirúrgica. MÉTODOS: Vinte e quatro ratos foram selecionados e divididos, igualmente, em três grupos (G1, G2 e G3). A laparotomia consistiu em uma incisão longitudinal mediana. Após obtido o acesso à cavidade abdominal, procedeu-se a síntese da ferida cirúrgica em dois planos através de sutura interrompida. As reoperações foram realizadas pelo mesmo acesso. No primeiro dia do experimento os 24 animais (G1, G2, G3) foram operados, no trigésimo dia 16 animais (G2, G3) foram reoperados e finalmente no sexagésimo dia os 8 animais do G3 foram operados pela terceira e última vez. Decorridos 30 dias da última laparotomia de cada grupo, foi procedida a eutanásia dos animais e ressecção da parede abdominal envolvida no acesso cirúrgico. Durante a ressecção foi realizada a avaliação macroscópica da ferida cirúrgica com avaliação de aderências e de outras possíveis complicações. A peça cirúrgica foi submetida ao estudo tensiométrico e em seguida foi preparada para o estudo histopatológico com lâminas coradas com picrosírius para quantificação e qualificação do colágeno. RESULTADOS: As aderências foram prevalentes nos grupos 2 (16 por cento) e 3 (16 por cento) quando comparadas com o grupo 1. Não houve diferença significante entre os grupos no estudo tensiométrico. O estudo histopatológico demonstrou diferença estatisticamente significativa nas concentrações de colágeno. Houve maior deposição de colágeno maduro (tipo I) e colágeno total nos grupos submetidos a mais de uma laparotomia (G2 e G3). Os animais do G3 apresentaram a maior concentração de colágeno maduro (p<0,0001) e colágeno total (p<0,0021), seguidos dos animais dos grupos 2 e 1 (nessa ordem). CONCLUSÃO: A maior concentração de colágeno maduro...

Interleukin-6 (IL-6) influence on colonic anastomosis healing in rats.

PURPOSE: To observe the effect of pro-inflamatory citokin, Interleukin-6 (IL-6), administration on the healing of colonic anastomosis in rats. METHODS: Thirty Wistar rats were divided into 2 groups of 15 animals each: a control group and an experiment group. The animals of the experiment group were submitted to injection of 500microg/kg of IL-6 Recombinant (Sandoz Phamarceutical(R)) subcutaneously 24 and 12 hours preceding the surgery, and the control group, were submitted to the injection of saline solution, using the same volume of solution as well as the way of administration. The rats were submitted to an end to end colonic anastomosis, being sacrificed in the 7th post-operative day, the site of the anastomosis was evaluated regarding to the adhesions that was quantified and the presence of complications was observed. The colon containing the anastomosis was submitted to a tensiometric study and a sample were sent for histological studies with HE and Sirius Red dye. RESULTS: The macroscopic and the tensiometric study did not demonstrate any significant differences between the control and experiment group. Regarding the histological evaluation, there was a significant reduction of the chronic inflammatory process in the experiment group (p=0,0209) and a lesser granulation area (p=0,0099). The total amount of collagen was similar in both groups, however, the experimental group showed a predominant area of immature collagen (p=0.009). CONCLUSIONS: The longer persistence of the acute phase of wound healing in the experiment group, as well as a decreased of the mature collagen type I, demonstrating that the IL-6 was harmful to the colonic healing anastomosis in rats.

Abdominal wall healing in reoperated rats.

PURPOSE: Experimental evaluation of the abdominal wall healing in reoperations on the same surgical site, by means of macroscopic analysis, histological and breaking strength studies of the surgical scar. METHODS: Twenty-four rats were selected and divided in 3 groups (G1, G2 and G3). A medium longitudinal laparotomy was performed, followed by laparorrhaphy on two synthesis planes, using an interrupted suture technique. The reoperations were performed in the same way, on the same surgical site. On the first day of the study all the 24 rats were operated, on the 30th day the 16 animals belonging to G2 and G3 were reoperated, and finally, on the 60th day, the 8 rats from G3 were operated for the third and last time. After 30 days of the last laparotomy of each group, euthanasia was performed. Complications such as adhesions were evaluated during the resection of surgical site. The breaking strength study was performed next, followed by the microscopical collagen analysis, using for that histological cuts stained with picrosirius. RESULTS: The adhesions were prevalent in G2 and G3 (16% each) when compared to G1. No significant difference was found in the breaking strength study. Statistically significant difference was observed in collagen concentration analysis. It was found higher mature collagen (type I) as well as total collagen concentration in the groups operated more than once (G2 and G3). The highest concentration of mature collagen (p<0,0001) and total collagen (p<0,0021) were found in G3 followed by G2 and G1 (in this sequence). CONCLUSION: The highest mature collagen concentration on the experimental groups, points out the importance of inflammatory activity in the healing process; in the resutures of the abdominal wall the surgical scar maturity is faster acquired than in the primary sutures; in relation to the primary sutures, the resutures of the abdominal wall did not influence in the resistance of the surgical scar.

Effects of venous supercharging in deep inferior epigastric artery perforator flap.

PURPOSE: To evaluate the effects of venous supercharging in deep inferior epigastric artery perforator flap in rats. METHODS: 20 Wistar rats were randomized in 2 groups: control group (C), all had flaps raised based on the deep inferior epigastric perforator vessels (DIEP), and experimental group (E), which was identical to group C, except that the contralateral superficial inferior epigastric vein was also kept with the flap. Flow studies using laser Doppler flowmetry where performed daily in the four zones of the flap. On the 7th postoperative day rats were killed and flap survival was determined using digital planimetry. RESULTS: Flow values were presented as a percentage of the baseline flow after incision of the flap edges. The surviving flap area was demonstrated as a percentage of the total flap area. Evaluation by digital planimetry showed that flap survival in group E was higher than in group C (97,38%+/-1,32%vs.44,13%+/-4,83%, p=0,0006). CONCLUSION: This study shows that venous supercharging of the rat DIEP flap results in greater flap survival.

Enxerto de submucosa porcina no tratamento de lesões duodenais em cães / Porcine submucosa graft for the treatment of duodenal injuries in dogs

OBJETIVO: Avaliar a biocompatibilidade e a eficiência da SID (submucosa de intestino delgado) porcina, quando usada como enxerto para reparar lesões duodenais. MÉTODOS: O estudo experimental foi realizado em oito cães. Um segmento da parede da segunda porção do duodeno foi ressecada e a lesão foi reparada com um enxerto de submucosa de intestino delgado porcina. No 120° dia de pós-operatório os animais foram submetidos a eutanásia e o segmento do duodeno com o enxerto foi retirado para avaliações macroscópica e microscópica. RESULTADOS: Não houve infecção, deiscência da sutura ou fístula. O estudo microscópico revelou completa re-epitelização em 75 por cento dos casos, com proliferação fibroblástica moderada em 87,5 por cento dos casos. CONCLUSÃO: A SID porcina é um enxerto eficaz para reparo de lesões com perda de substância em duodeno de cães.

[Comparative study of the biocompatibility of the porcine intestinal submucosa and bovine pericardium used as grafts in the inferior cava vein of dogs]. / Estudo comparativo da biocompatibilidade da submucosa intestinal porcina e pericárdio bovino usados como enxertos na veia cava de cães.

PURPOSE: To compare the biocompatibility of the bovine pericardium and the small intestine submucosa (SIS) when used to repair a created defect in the inferior vena cava of dogs. METHODS: Sixteen male mongrel dogs were submitted to a midline laparotomy incision. An elliptical segment (1.5 x 3.0 cm) of the inferior vena cava, below the renal veins, was excised. In 8 dogs, the A group, a patch of porcine small bowel submucosa was used to repair the defect. In the 8 remaining dogs, the B group, a bovine pericardium was implanted in the vena cava. On the 30th post-operative day an ultrasound was performed in order to identify stenosis. The euthanasia was accomplished in the 40th post-operative day. Stenosis of the vein was observed in 1 dog of A group and in 2 of the B group. RESULTS: Partial thrombosis with collateral circulation was evidenced in 1 dog of the bovine pericardium group. A moderated chronic inflammatory process was evidenced in both groups. Microscopic evaluation, regarding endothelization of the implant, collagen deposition, smooth muscle growth, was similar in both groups. CONCLUSION: SIS proved to be a functional graft patch for possessing local vena cava remodeling and its biocompatibility was similar to bovine pericardium.

[Porcine submucosa graft for the treatment of duodenal injuries in dogs]. / Enxerto de submucosa porcina no tratamento de lesões duodenais em cães.

PURPOSE: To evaluate the biocompatibility and effectiveness of porcine SIS (small intestinal submucosa), when used as a patch to repair a defect on the anterior duodenal wall. METHODS: The experimental study was performed in 8 dogs. A segment of the anterior duodenal wall was removed and the defect was repaired with a patch of porcine intestinal submucosa. On the 120th post operative day the animals were sacrificed and the segment of duodenum containing the patch was removed to a macroscopic and microscopic evaluation. RESULTS: There was no infection, suture dehiscence or fistula. The microscopic evaluation showed complete re-epithelization in 75% of the cases, with moderate fibroblastic proliferation in 87.5% of the cases. CONCLUSION: The porcine SIS used as a patch acts as a tissue substitute for repairing induced lesions in duodenal wall of dogs.

Estudo comparativo da biocompatibilidade da submucosa intestinal porcina e pericárdio bovino usados como enxertos na veia cava de cães / Comparative study of the biocompatibility of the porcine intestinal submucosa and bovine pericardium used as grafts in the inferior cava vein of dogs

OBJETIVO: Comparar a biocompatibilidade entre submucosa de intestino delgado (SID) porcino e o pericárdio bovino como enxerto no reparo de lesões criadas na veia cava inferior de cães. MÉTODOS: Dezesseis cães foram submetidos a laparotomia. Após a abertura da cavidade abdominal a veia cava foi identificada e em seguida procedeu-se com a retirada de um segmento elíptico de 1,5X3cm de sua parede anterior. Em 8 animais o defeito foi reparado com SID porcino (grupo A) e nos 8 animais restantes o defeito foi reparado com pericárdio bovino (grupo B).No 30º dia de P.O. realizou-se uma ultra-sonografia e a eutanásia foi realizada no 40ºdia de pós-operatório. RESULTADOS: Observou-se estenose da veia cava em 1 cão do grupo do grupo A e em 2 animais do grupo B além de trombose em 1 cão desse mesmo grupo. A análise microscópica revelou um processo inflamatório crônico moderado em ambos os grupos. A endotelizacão do enxerto, regeneracão de fibras musculares lisas e depósito de colágeno também foi similar nos 2 grupos estudados. CONCLUSAO: A SID provou ser um excelente substrato para a regeneracão vascular quando implantado em veia cava superior, contudo os resultados encontrados não diferem daqueles observados com o uso de pericárdio bovino.