Biodistribuição do pertecnetato de sódio após desvio gástrico em Y de Roux (técnica de capella)

O desvio gástrico em Y de Roux é a técnica cirúrgica mais utilizada no tratamento da obesidade mórbida. Esta operação reduz o volume do estômago e o comprimento do intestino delgado, gerando alterações estruturais e metabólicas que podem influenciar no resultado de exames cintilográficos de pacientes operados. Com o objetivo de avaliar a biodistribuição pós-operatória do pertecnetato de sódio (Na99mTc) em órgãos de ratos Wistar submetidos à técnica do bypass (desvio) gástrico em Y de Roux (BGYR), foram utilizados 12 ratos distribuídos aleatoriamente em grupo tratado (n=6), submetido à cirurgia do BGYR e o grupo controle (C; n=6). No 15º dia de pós-operatório foi administrado 0,1 mL via plexo orbital de Na99mTc aos animais dos dois grupos, com atividade radioativa média de 0,66MBq. Após 30 minutos, os ratos foram mortos e retirados fragmentos de tireóide, coração, pulmão, fígado, estômago, rim e fêmur. As amostras foram lavadas com solução salina 0,9%, pesadas e submetidas ao Contador Gama 1470, WizardTM Perkin-Elmer-Finlândia para determinação do percentual de atividade radioativa total por grama (%ATI/g) de cada órgão. Empregou-se o teste t de Student para análise estatística, considerando-se significantes as diferenças das médias quando p<0,05. Redução significante na média de %ATI/g foi observada no fígado, estômago e fêmur dos animais submetidos à cirurgia de BGYR comparada ao grupo controle (p<0,05). Nos demais órgãos não houve diferença estatisticamente significativa entre os grupos. Em conclusão, a cirurgia BGYR em ratos modificou a biodistribuição do Na99mTc em alguns órgãos, podendo ter implicações clínicas na interpretação de exames cintilográficos. Este estudo xi teve um caráter multidisciplinar com a participação de pesquisadores das áreas de Cirurgia Experimental, Farmácia, Radiobiologia, Medicina Nuclear e Estatística

Relação entre estresse oxidativo e oesteopenia diabética em ratas pré-menopausadas

The relationship between lipid peroxidation, antioxidant defense and diabetic osteopenia remains unclear. This study evaluated the relationship between lipid peroxidation index, antioxidant defense parameter and bone metabolism in a premenopausal diabetic model by measurements such as thiobarbituric acid-reactive substances concentration (TBARS) and reduced glutathione (GSH) content in brain homogenates, histomorphometric analysis, biomechanical testing and bone mineral density (BMD). Female Wistar rats with regular estrous cycle were divided into two groups: Group 1: control rats (n = 15) and Group 2: diabetic rats (n = 15). Diabetes mellitus was induced by alloxan and confirmed by glycemia 250 mg/dL. The experimental period understood 1 and 5 after days induction and 45, 75 and 120 days after the installation of diabetes mellitus.The lipid peroxidation index, measured by TBARS concentration, showed a significant increase (p<0.05) in diabetic animals in comparison to animals control. However, the antioxidant parameter, measured by GSH content, was significantly decrease (p<0.05) in diabetic animals. Histomorphometric analysis showed a significant increase (p<0.05) in femoral trabecular separation together with a significant decrease (p<0.05) in trabecular thickness and reduced trabecular bone volume in diabetic rats. Moreover, biomechanical testing and BMD values were significant decrease (p<0.05) in diabetic group. Thus, our results demonstrated that increased lipid peroxidation and altered antioxidant defense could be related to the development of oxidative stress and diabetic osteopenia in premenopausal rats

Influência da esplenectomia na biodistribuição do ácido dimercaptosuccínico-tecnécio-99m (99mTc-DMSA) em ratos Wistar

A esplenectomia é indicada em doenças hematológicas, hiperesplenismo grave, traumas e tem sido causa de importantes alterações metabólicas e imunológicas. O objetivo do presente trabalho é avaliar se a retirada do baço altera a biodistribuição do radiofármaco DMSA Tc99m em ratos Wistar e se há correlação com possíveis alterações da função renal. Foram usados dois grupos: esplenectomia (n=6) e controle (n=6) animais não operados. Após 15 dias, foi administrado 0,1 ml de DMSA-Tc99m via plexo orbital (0,66 MBq). Trinta minutos depois, foram retiradas amostras do rim, coração, pulmão, tireóide, estômago, bexiga, fêmur, sangue. Após pesadas as amostras, foi determinado o percentual de radioatividade/g (% ATI/g) em cada uma delas, com o Wizard Gama Counter Perkin-Elmer . Dosadas uréia e creatinina sérica, hematócrito, plaquetas e leucócitos. Estatística pelo teste t, com significância 0,05. Foi observada redução significante no %ATI/g no rim e sangue (p<0,05) dos animais esplenectomizados, aumento significante (p<0,05) da uréia (88,8±18,6mg/dL) e creatinina (0,56±0,08), comparado aos controles (51,5±1,6 e 0,37±0,02mg/dL, respectivamente) assim como leucocitose, aumento de plaquetas e redução de hematócrito. Em conclusão, a esplenectomia provocou comprometimento da função renal, repercutindo na alteração da captação de DMSA 99mTc pelo rim de ratos. Uma parceria entre a Unidade de Medicina Nuclear da Liga Norteriograndense Contra o Câncer e o Núcleo de Cirurgia Experimental da Universidade Federal do Rio Grande doNorte tornou possível a realização deste trabalho, que contou com a participação de profissionais de diferentes áreas como: Biologia, Biomedicina, Medicina Nuclear, Cirurgia Geral, Bioquímica e Estatística, atestando dessa forma o caráter multidisciplinar do trabalho

Biodistribuição do pertecnetato de sódio após cirurgia do Switch Duodenal

The biliopancretic diversion with duodenal switch is one of the mixing techniques used in the treatment of morbid obesity. The duodenal switch reduces the stomach capacity and leaves only 50-100 cm of small intestine for nutrition and absorption. The surgery produces hormonal, structural and biochemical changes, which can influence on the result of scintigraphic examinations in operated patients. With the objective of evaluate the postoperative biodistribution of sodium pertechnetate (Na99mTcO4) in brain, thyroid, heart, lung, liver, spleen, kidney, stomach, duodenum, pancreas, small intestine, bladder, muscle and bone of Wistar rats. The rats were randomly allocated into 3 groups of 7 rats each: the duodenal switch group (DS), the control group (C) and the sham group (S). They were operated under anesthesia and aseptic technique. In the tenth postoperative day, 0.1mL of sodium pertechnetate was injected via orbital plexus. After 30 min the animals were killed with overdose of anesthetic and samples of liver, spleen, pancreas, stomach, duodenum, small intestine, thyroid, lung, heart, kidney, bladder, muscle, bone and brain were harvested, washed with saline and weighed. The detention of radioactivity was made using the automatic Gamma Counter Wizard, PerkinElmer and the percentage of activity per gram of tissue (%ATI/g) was calculated. There was no early or late mortality in either rats groups. The values of percent radioactivity per gram of tissue (%ATI/g), showed no significant difference in liver, stomach, small bowel, duodenum, kidney, heart, bladder, bone and brain, when compared the DS rats with sham and controls rats. A postoperative significant increase in mean %ATI/g levels was observed in spleen, pancreas and muscle in group DS rats, as compared to group S and C rats (p<0.05). In the lung there was an increase and in thyroid a decrease in mean %ATI/g of DS rats, when compared to sham rats (p>0.05). In conclusion, the biliopancreatic diversion with duodenal switch in rats modified the biodistribution of sodium pertechnetate in thyroid, lung, pancreas, spleen and muscle. The study had the participation of the departments and laboratories researches, as Nucleus of Experimental Surgery, Department of Surgery, Laboratory of Radiobiology, Department of Pathology and Service of Nuclear Medicine, certifying the character of a multidisciplinary research

Biodistribuição do pertecnetato de sódio (Na99mTcO4) em ratos submetidos à ressecção extensa de intestino delgado

Massive resection of the small intestine results in short bowel syndrome with anti-absorptive effect and repercussions on the metabolism. Morphologic and functional evaluation may be necessary in order to control wrapped organs. Scintigraphy an examination with little invading and no biologic damage can be used. The purpose were to assess the biodistribution of sodium pertecnetate in organs of rats subjected to massive resection of the small intestine, the intestinal adaptation of the remnant intestinal mucosa and weight curve evaluation in the postoperative period. Twenty-one Wistar rats were randomly allocated into three groups (n = 7). The operated group named short bowel (SB) after anesthetized was subjected to massive resection of the small intestine; the control group (C), and sham group (SHAM). On the 30th postoperative day, 0.l mL of sodium pertechnetate was injected into the venous orbital plexus. After 30 minutes, the rats were killed with an overdose of anesthetic, and fragments of the liver, spleen, pancreas, stomach, duodenum, small intestine, thyroid, lung, heart, kidney, bladder, muscle, femur and brain were harvested. The percentage of radioactivity per gram of tissue (%ATI/g) was determined using Gama Counter WizardTM 1470, PerkinElmer to all samples. Biopsies of 3 cm remaining jejunum were removed to histological analyses. Analysis of variance (ANOVA) and the Tukey test for multiple comparisons were used, considering p<0.05 as significant. The study had the participation of some departments and laboratories, as Nucleus of Experimental Surgery, Department of Surgery, Laboratory of Radiobiology, Department of Pathology and Service of Nuclear Medicine, certifying the character of a multidisciplinary research. The results were no significant differences in %ATI/g of the sodium pertechnetate in the organs of the groups studied (p>0.05). An increase in the weight of the SB rats was observed after the second postoperative week. The jejunal mucosal thickness of the SB rats was significantly greater than that of C and sham rats (p<0.05. The biodistribution of sodium pertechnetate was not affected by massive intestinal resection in rats. An adaptive response by the intestinal mucosa probably contributed to the reversion of weight loss and the biodistribution of sodium pertechnetate was not affected by the surgery