SUELLEN SERAFINI
Projetos de Pesquisa
Unidades Organizacionais
LIM/30 - Laboratório de Investigação em Cirurgia Pediát, Hospital das Clínicas, Faculdade de Medicina
4 resultados
Resultados de Busca
Agora exibindo 1 - 4 de 4
- Analysis of the reversibility of biliary cirrhosis in young rats submitted to biliary obstruction(2018) BRAZ, Maria Julia de Aro; CORBI, Leonardo Ervolino; TANNURI, Ana Cristina Aoun; COELHO, Maria Cecilia Mendonca; GONCALVES, Josiane Oliveira; SERAFINI, Suellen; TANNURI, UenisBackground/purpose: Biliary atresia and other liver biliary obstructions are relevant conditions in pediatric surgery due to their progression to biliary cirrhosis and indication for liver transplantation. It is known that the period during which biliary obstruction persists determines the development of cirrhosis and its reversibility after a biliary drainage procedure. However, no time or histological markers of biliary cirrhosis reversibility have been established. Materials and methods: One hundred and twenty-nine young Wistar rats underwent surgery for ligation of the common bile duct and were maintained until 8 weeks. A part of these animals was submitted to biliary drainage surgery at 2, 3, 4, 5, or 6 weeks after the initial procedure. After cyst formation at the site of obstruction, cystjejunal anastomosis was performed to restore bile flow. After biliary obstruction and drainage, liver samples were collected for histological and molecular analysis of the genes responsible for collagen deposition and fibrosis. Results: The mortality rates were 39.8% and 56.7% after the first and second procedures, respectively. Ductular proliferation (p = 0.001) and collagen deposition increased according to the period under obstruction (p = 0.0001), and both alterations were partially reduced after biliary drainage. There were no significant differences in the values of desmin and alpha-actin according to the period during which the animal remained with biliary obstruction (p = 0.09 and p = 0.3, respectively), although increased values of transforming growth factor beta 1 (TGF beta 1) occurred after 8 weeks (p = 0.000). Desmin levels decreased, and alpha-actin and TGF beta 1 levels increased according to the period under obstruction. The molecular alterations were partially reversed after biliary drainage. Conclusions: The histologic and molecular changes in the liver parenchyma promoted by biliary obstruction in the young animal can be partially reversed by a biliary drainage procedure.
- Is maintenance of the ileocecal valve important to the intestinal adaptation mechanisms in a weaning rat model of short bowel?(2018) BARROS, Guilherme Garcia; TANNURI, Ana Cristina Aoun; ROTONDO, Italo Gerardo; VAISBERG, Vitor Van; SARMENTO, Leandro Silveira; NETO, Cicero Mendes; SERAFINI, Suellen; GONCALVES, Josiane de Oliveira; COELHO, Maria Cecilia Mendonca; TANNURI, UenisPurpose To evaluate the role of maintenance of the ileocecal valve (ICV) in intestinal adaptation mechanisms, in a weaning rat experimental model of short bowel. Methods Forty animals were operated on to produce short bowel syndrome. They were divided into five groups: maintenance (MV) or resection of ICV (RV), kill after 4 days (MV4 and RV4) or 21 days (MV21 and RV21), and a control group (21-day-old rats). Body weights, small bowel and colon lengths and diameters, villus heights, crypt depths, lamina propria and muscle layer thickness, as well as the apoptosis index of villi and crypts and expression of pro-and anti-apoptotic genes, were studied. Results Preservation of the ICV promoted increased weight gain (p = 0.0001) and intestinal villus height after 21 days; crypt depth was higher in comparison to controls. It was verified a higher expression of Ki-67 in bowel villi and crypts (p = 0.018 and p = 0.015, respectively) in RV4 group and a higher expression in bowel villi of MV4 group animals (p = 0.03). The maintenance of ICV promoted late increased expression of the anti-apoptotic gene Bcl-XL in the colon (p = 0.043, p = 0.002, p = 0.01). Conclusion The maintenance of the ICV led to positive changes in this model.
- Are there differences in the growth adaptation processes of growing and mature organism models of short bowel syndrome?(2018) TANNURI, Ana Cristina Aoun; ROTONDO, Italo Geraldo; BARROS, Guilherme Garcia; VAISBERG, Victor Van; MENDES-NETO, Cicero; PAES, Vitor Ribeiro; COELHO, Maria Cecilia Mendonca; GONCALVES, Josiane; SERAFINI, Suellen; TANNURI, UenisOBJECTIVES: The purpose of this study was to present an experimental model of short bowel syndrome (SBS) in weaning rats and to compare the adaptative mechanisms of the remaining bowel in weaning rats and adult animals by means of morphometric, histologic and molecular methods. METHODS: Twenty-four weaning rats were divided into 3 groups of 8 animals, one control group and two short bowel groups (euthanasia after 4 and 21 days), and were compared with similar adult groups. Morphometric evaluations of the animals and histopathological and molecular studies of the remaining bowel were performed. RESULTS: The weight of young rats increased after enterectomy, whereas that of adult rats decreased after enterectomy (p < 0.0001). The ratio of intestinal length/body weight was significantly higher in weaning rats than in adults (p < 0.002), showing that intestinal growth was more intense in weaning rats. Intestinal resection promoted increased thickness of the small bowel lamina propria (p=0.001) and reduced thickness of the colon lamina propria (p=0.04) in weaning rats relative to those in adults. In addition, intestinal resection promoted increased expression of the Bcl-xl gene (antiapoptotic) in adult animals compared with that in weaning rats (p=0.001). CONCLUSION: Morphometric, histological and molecular differences were shown in the adaptation processes of growing and mature organisms.
- Remote Ischemic Preconditioning Is Efficient in Reducing Hepatic Ischemia-Reperfusion Injury in a Growing Rat Model and Does Not Promote Histologic Lesions in Distant Organs(2018) GOMES, P. F. M.; TANNURI, A. C. A.; NOGUEIRA, T. M.; LUAMOTO, L. R.; PAES, V. R.; COELHO, M. C. M.; GONCALVES, J. O.; SERAFINI, S.; TANNURI, U.Objective. Ischemic preconditioning (IPC) was developed to diminish ischemia-reperfusion injury (IRI). There are two main ways of performing it: direct ischemic-preconditioning (DIP) and remote ischemic-preconditioning (RIP). The objectives of this study were to investigate local and systemic effects of DIP and RIP in liver IRI. Methods. Thirty-two weaning rats (50-70 g body weight; 21 days old) were divided into 4 groups: control (C); ischemia followed by reperfusion (IR); DIP followed by ischemia and reperfusion; and RIP followed by ischemia and reperfusion. In the IR group, the vascular pedicles of medial and left lateral liver lobes were clamped for 60 minutes and then unclamped. In the DIP group, a 10-minute cycle of ischemia followed by a 10-minute reperfusion of the same lobes was performed before 60 minutes of ischemia. In the RIP group, three 5-minute cycles of clamping and unclamping of the femoral vessels were performed before liver ischemia. The animals were euthanized 24 hours after the surgical procedures. Results. The serum levels of liver enzymes were significantly lower in the RIP group compared to the control and IR groups and to the DIP group. The scores of histologic hepatic lesions were significantly lower in RIP animals than those of IR animals (P = .002) and similar to the C group animals. The Bax/BCl-xl relation was lower in the DIP group than that in the RIP group (P = .045) and no differences were observed in histologic analyses of kidney, lung, intestine, and heart. Conclusion. In young animals, the beneficial effects of RIP are more evident than those of DIP.