ABSTRACT Purpose: To evaluate the effect of preoperative intravenous chemotherapy with 5-fluorouracil on liver regeneration in an experimental model of major hepatectomy in rats. Methods: Wistar rats were divided into two groups of 20 animals each and submitted to 70% hepatectomy 24 h after intravenous injection of 5-fluorouracil 20 mg/kg (fluorouracil group, FG) or 0.9% saline (control group, CG). After hepatectomy, each group was subdivided into two subgroups of 10 animals each according to the day of sacrifice (24 h or 7 days). Liver weight during regeneration, liver regeneration rate using Kwon formula, and the immunohistochemical markers proliferating cell nuclear antigen (PCNA) and Ki-67 were used to assess liver regeneration. Results: At early phase (24 h after hepatectomy) it was demonstrated the negative effect of 5-fluorouracil on liver regeneration when assessed by Kwon formula (p < 0.0001), PCNA analysis (p = 0.02). With regeneration process complete (7 days), it was possible to demonstrate the sustained impairment of chemotherapy with 5-fluorouracil on hepatocytes regeneration phenomenon when measured by Kwon formula (p = 0.009), PCNA analysis (p = 0.0001) and Ki-67 analysis (0.001). Conclusions: Preoperative chemotherapy with intravenous 5-fluorouracil negatively affected the mechanisms of liver regeneration after major hepatectomy in rats.

Abstract Purpose: To evaluate the effects of low-frequency electric stimulation on biomechanics following surgical treatment of the Achilles tendon in rats. Methods: Forty-two rats were divided into two groups. One was given electric stimulation and the other was not. All were submitted to Achilles tenotomy and tenorrhaphy performed with a modified Kessler stitch. The experiment group underwent electric stimulation with 2 Hz, a nonpolarized current of 1 mA intensity for 14 days. The animals were euthanized at 2, 4 and 6 weeks for the biomechanical study. Results: The work performed, that is, the tendon’s capacity to absorb energy until rupture, was greater in the electrically stimulated group in the 2nd (p = 0.032) and in the 6th week (p = 0.010). The maximum tension, which is the capacity to support a load, was higher in the treated group in the 2nd (p = 0.030) and the 6th week (p = 024). These results indicate greater resistance of the electrically stimulated tendons. An analysis of the elastic module showed no differences. Conclusion: Low-frequency electric stimulation increased the resistance of the tendons at 2 and 6 weeks of evolution in rats.

RESUMO Racional: As hepatectomias compreendem considerável perda sanguínea e utilização de hemoderivados, o que diretamente estão relacionados com maior morbimortalidade. A hepatectomia hemoconservadora (HH) é modificação da técnica de oclusão vascular seletiva em hepatectomia. Ela pode ser alternativa cirúrgica para evitar ou diminuir o uso de hemoderivados no perioperatório. Objetivo: Avaliar os efeitos da HH sobre o volume globular (VG), concentração de hemoglobina (HB) e sobre a regeneração hepática em ratos. Métodos: Dois grupos de ratos Wistar foram constituídos: controle (n=6) e intervenção (n=6). Os do grupo controle foram submetidos à hepatectomia parcial de Higgins e Anderson e os do grupo Intervenção à HH. VG e HB foram medidos nos dias D0, D1 e D7. A relação peso do fígado/peso do rato foi calculada em D0 e D7. A regeneração hepática foi analisada qualitativamente e quantitativamente. Resultados: Houve diminuição dos níveis de VG e HB nos ratos do grupo controle a partir de D1, atingindo decréscimo de 18% em D7 (p=0,01 e p=0,008 respectivamente); a HH permitiu a manutenção dos níveis de VG e HB nos ratos do grupo intervenção. A HH não alterou a regeneração hepática. Conclusão: HH resultou em níveis maiores de VG e HB pós-operatórios sem alterar a regeneração hepática. Pode-se considerar estes dados como a prova necessária para a translação à pesquisa clinicocirúrgica.

ABSTRACT Background: Hepatectomies promote considerable amount of blood loss and the need to administrate blood products, which are directly linked to higher morbimortality rates. The blood-conserving hepatectomy (BCH) is a modification of the selective vascular occlusion technique. It could be a surgical maneuver in order to avoid or to reduce the blood products utilization in the perioperative period. Aim: To evaluate in rats the BCH effects on the hematocrit (HT) variation, hemoglobin serum concentration (HB), and on liver regeneration. Methods: Twelve Wistar rats were divided into two groups: control (n=6) and intervention (n=6). The ones in the control group had their livers partially removed according to the Higgins and Anderson technique, while the rats in the treatment group were submitted to BCH technique. HT and HB levels were measured at day D0, D1 and D7. The rate between the liver and rat weights was calculated in D0 and D7. Liver regeneration was quantitatively and qualitatively evaluated. Results: The HT and HB levels were lower in the control group as of D1 onwards, reaching an 18% gap at D7 (p=0.01 and p=0.008, respectively); BCH resulted in the preservation of HT and HB levels to the intervention group rats. BCH did not alter liver regeneration in rats. Conclusion: The BCH led to beneficial effects over the postoperative HT and serum HB levels with no setbacks to liver regeneration. These data are the necessary proof of evidence for translational research into the surgical practice.

RESUMO Racional: A enteroscopia por duplo balão é importante método endoscópico para abordagem do intestino delgado, permitindo o diagnóstico e a terapêutica de afecções com baixa taxa de complicações. Objetivo: Análise de pacientes submetidos à enteroscopia por duplo balão, estabelecendo as indicações para realização do exame e seus achados, analisando a terapêutica realizada e observando as complicações decorrentes do procedimento. Métodos: Estudo retrospectivo de análise de 65 prontuários de pacientes submetidos à enteroscopia por duplo balão. Os dados foram armazenados em planilhas e foi realizada a análise estatística. Resultados: Foram 65 enteroscopias em 50 pacientes, sendo 63,1% mulheres e 36,9% homens, com média de idade de 50,94 anos. A principal indicação foi sangramento intestinal, seguida por dor abdominal e doença de Crohn. A maioria dos procedimentos foi considerada normal, sendo que o achado mais prevalente foram os pólipos, seguido por angioectasias e duodenites. Em 49,2% dos exames foi realizado algum procedimento terapêutico, sendo a biópsia o mais prevalente. Houve apenas um caso de complicação de pancreatite aguda. Conclusão: A enteroscopia por duplo balão é bom e seguro método para a avaliação do intestino delgado, possuindo como principais indicações o sangramento intestinal e a dor abdominal. Possui baixas taxas de complicações e, por meio de suas opções terapêuticas, diminui a necessidade de procedimentos cirúrgicos.

ABSTRACT Background: The double balloon enteroscopy is an important method for the endoscopic approach of the small bowel that provides diagnosis and therapy of this segment’s disorders, with low complication rate. Aim: Analysis of patients undergoing double balloon enteroscopy. The specific objectives were to establish the indications for this method, evaluate the findings by the double balloon enteroscopy, analyze the therapeutic options and the complications of the procedure. Methods: It is a retrospective analysis of 65 patients who underwent double balloon enteroscopy. Results: Sixty-five procedures were performed in 50 patients, 63.1% were women and 36.9% were men. The mean age was 50.94 years. The main indication it was gastrointestinal bleeding, followed by abdominal pain and Crohn’s disease. Most procedures were considered normal. Polyps were the most prevalent finding, followed by angioectasias and duodenitis. In 49.2% of the cases, one or more therapeutic procedures were performed, (biopsy was the most prevalent). There was only one case of acute pancreatitis, which was treated clinically. Conclusion: The enteroscopy is good and safe method for the evaluation of the small bowel, and its main indications are gastrointestinal bleeding and abdominal pain. It has low complications rates and reduces the necessity of surgery.