SUELLEN SERAFINI
Projetos de Pesquisa
Unidades Organizacionais
LIM/30 - Laboratório de Investigação em Cirurgia Pediát, Hospital das Clínicas, Faculdade de Medicina
20 resultados
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Agora exibindo 1 - 10 de 20
- 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.
- Impact of Three Methods of Ischemic Preconditioning on Ischemia-Reperfusion Injury in a Pig Model of Liver Transplantation(2022) BELON, Alessandro Rodrigo; TANNURI, Ana Cristina Aoun; MOREIRA, Daniel de Albuquerque Rangel; FIGUEIREDO, Jose Luiz; SILVA, Alessandra Matheus da; SERAFINI, Suellen; GUIMARAES, Raimundo Renato; FARIA, Caroline Silverio; ALEXANDRE, Alcione Sanches de; GONCALVES, Josiane Oliveira; PAES, Vitor Ribeiro; TANNURI, UenisBackground Ischemic preconditioning (IPC), either direct (DIPC) or remote (RIPC), is a procedure aimed at reducing the harmful effects of ischemia-reperfusion (I/R) injury. Objectives To assess the local and systemic effects of DIPC, RIPC, and both combined, in the pig liver transplant model. Materials and methods Twenty-four pigs underwent orthotopic liver transplantation and were divided into 4 groups: control, direct donor preconditioning, indirect preconditioning at the recipient, and direct donor with indirect recipient preconditioning. The recorded parameters were: donor and recipient weight, graft-to-recipient weight ratio (GRWR), surgery time, warm and cold ischemia time, and intraoperative hemodynamic values. Blood samples were collected before native liver removal (BL) and at 0 h, 1 h, 3 h, 6 h, 12 h, 18 h, and 24 h post-reperfusion for the biochemical tests: aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), gamma-glutamyl transferase (GGT), creatinine, BUN (blood urea nitrogen), lactate, total and direct bilirubin. Histopathological examination of liver, gut, kidney, and lung fragments were performed, as well as molecular analyses for expression of the apoptosis-related BAX (pro-apoptotic) and Bcl-XL (anti-apoptotic) genes, eNOS (endothelial nitric oxide synthase) gene, and IL-6 gene related to inflammatory ischemia-reperfusion injury, using real-time polymerase chain reaction (RT-PCR). Results There were no differences between the groups regarding biochemical and histopathological parameters. We found a reduced ratio between the expression of the BAX gene and Bcl-XL in the livers of animals with IPC versus the control group. Conclusions DIPC, RIPC or a combination of both, produce beneficial effects at the molecular level without biochemical or histological changes.
- Is hematoxylin-eosin staining in rectal mucosal and submucosal biopsies still useful for the diagnosis of Hirschsprung disease?(2017) SERAFINI, Suellen; SANTOS, Maria Merces; TANNURI, Ana Cristina Aoun; ZERBINI, Maria Claudia Nogueira; COELHO, Maria Cecilia de Mendonca; GONCALVES, Josiane de Oliveira; TANNURI, UenisBackground: Hematoxylin-eosin (HE) staining of a full-thickness rectal wall fragment is classically used for the diagnosis of Hirschsprung disease (HD). However, this technique requires large fragments for a better diagnosis. Additionally, the histochemical and immunohistochemical methods of staining small fragments of rectal mucosal and submucosal biopsies are not available in all centers. Therefore, the possibility of diagnosing HD through HE staining in these biopsies could be a valuable alternative for centers that do not have more specific techniques. The objectives of the current investigation were to evaluate the concordance of the results obtained by HE staining and the calretinin method with acetylcholinesterase (AChE) activity in fragments of mucosa and submucosa in the diagnosis of HD. Methods: For this study, 50 cases from our laboratory were selected. The tissue material was embedded in paraffin. Sixty levels of each fragment were utilized for HE, and the other 3 levels were used for calretinin. These slides were analyzed under the microscope, photographed and classified as either positive for HD when no ganglion cells were found with nerve trunks present or as negative when ganglion cells were found. The results from reading the slides were compared with those of AChE. Results: Of the 50 cases evaluated by the HE technique, only 5 contradicted the diagnosis based on AChE, with a Kappa value of 0.800 and an accuracy of 90%. In the comparison between calretinin and AChE, 8 cases were discordant, with a Kappa value of 0.676 and an accuracy of 84%. Conclusions: The concordance of results from AChE and HE methods was satisfactory, allowing for the potential use of the HE method for fragments of mucosa and submucosa as a valid alternative in the diagnosis of HD. The immunohistochemical technique of calretinin did not show good agreement with the AChE activity in our study.
- A simplified experimental model of large-for-size liver transplantation in pigs(2013) LEAL, Antonio Jose Goncalves; TANNURI, Ana Cristina Aoun; BELON, Alessandro Rodrigo; GUIMARAES, Raimundo Renato Nunes; COELHO, Maria Cecilia Mendonca; GONCALVES, Josiane de Oliveira; SOKOL, Suellen Serafini; MELO, Evandro Sobroza De; OTOCH, Jose Pinhata; TANNURI, UenisOBJECTIVE: The ideal ratio between liver graft mass and recipient body weight for liver transplantation in small infants is unknown; however, if this ratio is over 4%, a condition called large-for-size may occur. Experimental models of large-for-size liver transplants have not been described in the literature. In addition, orthotopic liver transplantation is marked by high morbidity and mortality rates in animals due to the clamping of the venous splanchnic system. Therefore, the objective of this study was to create a porcine model of large-for-size liver transplantation with clamping of the supraceliac aorta during the anhepatic phase as an alternative to venovenous bypass. METHOD: Fourteen pigs underwent liver transplantation with whole-liver grafts without venovenous bypass and were divided into two experimental groups: the control group, in which the weights of the donors were similar to the weights of the recipients; and the large-for-size group, in which the weights of the donors were nearly 2 times the weights of the recipients. Hemodynamic data, the results of serum biochemical analyses and histological examination of the transplanted livers were collected. RESULTS: The mortality rate in both groups was 16.5% (1/7). The animals in the large-for-size group had increased serum levels of potassium, sodium, aspartate aminotransferase and alanine aminotransferase after graft reperfusion. The histological analyses revealed that there were no significant differences between the groups. CONCLUSION: This transplant method is a feasible experimental model of large-for-size liver transplantation.
- Effects of local and remote ischemic postconditioning methods on ischemia-reperfusion injury in a young animal model of acute mesenteric ischemia(2023) ABREU, Mateus Souza; TANNURI, Ana Cristina Aoun; RODRIGUES, Rafael Felipe Goncalves; SILVA, Rafael Jose da; GONCALVES, Josiane de Oliveira; SERAFINI, Suellen; TANNURI, UenisPurpose: Acute mesenteric ischemia (AMI) is a condition in pediatric surgery that ranges from intestine necrosis to death. Ischemic postconditioning (IPoC) methods were developed to reduce the damage caused by revascularization. This study aimed to evaluate the efficacy of these methods in an experimental weaning rat model. Methods: Thirty-two 21-day-old Wistar rats were allocated into four groups according to the surgical procedure performed: control, ischemia-reperfusion injury (IRI), local (LIPoC) and remote IPoC (RIPoC). At euthanasia, fragments of the intestine, liver, lungs, and kidneys were submitted to histological, histomorphometric, and molecular analyses. Results: In the duodenum, intestines, and kidneys histological alterations promoted by IRI were reversed by remote postconditioning method. In the distal ileum, the histomorphometric alterations could be reversed by the postconditioning methods with more evident effects promoted by the remote method. The molecular analysis found that the levels of expression of Bax (proapoptotic) and Bcl-XL (antiapoptotic) genes in the intestine were increased by IRI. These alterations were equally reversed by the postconditioning methods, with more evident effects of the remote method. Conclusion: IPoC methods positively reduced the damage caused by IRI in weaning rats.
- Sepsis and cirrhosis in growing animals: description of a new experimental model and its pathological and immunological reliability(2020) MORAES, Pedro Augusto Dantas de; TANNURI, Ana Cristina Aoun; RIOS, Livio Moreira; PEES, Vitor Ribeiro; GONCALVES, Josiane de Oliveira; SERAFINI, Suellen; TANNURI, UenisOBJECTIVES: In cirrhotic children, infection events and sepsis are more frequent and more severe due to immune dysfunction. The objectives of the current study were therefore to develop an experimental model of infection and sepsis in cirrhotic weaning growing rats, by the use of bile duct ligation (BDL) and cecal ligation and puncture (CLP). Additionally, the correlation of the clinico-histopathological data and serial cytokine levels in septic cirrhotic and non-cirrhotic animals was studied. METHODS: Young Wistar rats of age 21 days and of weight between 70-90 g were divided into 12 groups according to the surgical procedure performed: sham (sacrificed after 2 or 4 weeks), BDL (sacrificed after 2 or 4 weeks), CLP (2- or 4-week old animals sacrificed after 12 or 24 hours), BDL+CLP (2- or 4-week old animals sacrificed after 12 hours). Histopathological studies and determination of serum levels of cytokines IL-1 beta, IL10, and TNF-alpha, for studies of systemic infection, were performed. Murine sepsis scores (MSS) based on the clinical aspects just before euthanasia were also included. RESULTS: A transitory increase in IL-1, IL-10, and TNF-alpha levels was observed, with different patterns according to the groups. Two-hit groups tended to present with higher values of serum cytokines and histopathological scores than their septic non-cirrhotic counterparts. There was a correlation between mortality rate and MSS (p<0.0001). CONCLUSION: The model is feasible and may be utilized in studies on liver cirrhosis and infection in growing animals.
- 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.
- Cardiac and renal effects of liver cirrhosis in a growing animal model(2021) TANNURI, Ana Cristina Aoun; CHAVEZ, Leiliane Somoggi; GUIMARAES, Juliana Xavier; GONCALVES, Josiane de Oliveira; SERAFINI, Suellen; SOUZA, Gabriela Carvalho de; MALHEIROS, Denise Maria Avancini Costa; PAES, Vitor Ribeiro; TANNURI, UenisPurpose: To assess the biochemical, histological, histomorphometric and molecular effects of biliary duct ligation (BDL) induced liver cirrhosis in the heart and kidneys. Methods: Thirty-two weaning rats (21 days old, 50-70 g) underwent BDL and were divided in four groups (euthanasia after two, four, six, and eight weeks, respectively) and compared to control groups. Results: The animals' hearts of group 3 were bigger than those of the control group (p=0.042), including thinner right ventricle wall, decreased internal diameter of ventricles, and increased perivascular collagen deposition in left ventricle, as well as increased interstitial collagen in right ventricle after six weeks. In the kidneys of groups 3 and 4, bilirubin impregnation in the tubules, hydropic degeneration, loss of nuclei and lack of plasmatic membrane limits were noted. Nitric oxide synthase (NOS) gene expressions were higher in group 1 (p=0.008), and endothelial nitric oxide synthase (eNOS) gene expressions were elevated in all experimental groups (p=0.008, p=0.001, p=0.022, and p=0.013, respectively). In the heart, a decreased expression of eNOS in group 1 (p=0.04) was observed. Conclusions: Liver cirrhosis leads to histological and histomorphometric alterations in the heart and kidneys, with changes in the NOS and eNOS gene expressions, that may suggest a role in the associated myocardial and renal manifestations.
- Adaptation Processes of the Remaining Jejunum or Ileum after Extensive Intestinal Resection(2022) MUSSOLINO, Affonso Flavio Jorge; TANNURI, Ana Cristina Aoun; GONCALVES, Josiane de Oliveira; SERAFINI, Suellen; TANNURI, UenisPurpose To compare the adaptation processes of the remaining jejunum or ileum after extensive intestinal resection in a growing animal model. Materials and Methods Forty 21-day old rats were divided into four groups: JG: remaining jejunum group - ileal enterectomy; IG: ileum remaining group - jejunum enterectomy; SHAM: sham-operated group - open-and-close laparotomy; and NO: non-operated animals. Results After 3 weeks, JG and IG animals had decreased weights comparing to SHAM and NO animals (p = 0.017 and p = 0.005, respectively). The histomorphometric analysis showed that in JG animals the villi were higher than in SHAM, NO, and IG animals (p = 0.007, p = 0.008, and p = 0.01), the depth of crypts in JG and IG animals was greater than in NO and SHAM animals (p = 0.03, p = 0.002, and p = 0.003 respectively), and muscle layer thickness of the jejunum of JG animals had values greater than SHAM and NO animals (p = 0.01 and p = 0.02, respectively). The Ki-67 expression in the ileum was higher in comparison with the jejunum (p = 0.014). The pro-apoptotic gene (Bax) expression was decreased in JG animals compared to IG, SHAM, and NO animals (p = 0.013, p = 0.024, and p = 0.021). The anti-apoptotic gene (Bcl-XL) expression was decreased in JG animals in comparison to IG and NO animals (p = 0.002 and p = 0.046) although it was increased in the colon of IG animals in comparison to JG, SHAM, and NO animals (p = 0.002, p = 0.001, and p = 0.001, respectively). The Bax/Bcl-XL ratio was higher in JG than in IG animals (p = 0.011). Conclusion Adaptive responses seemed to be more effective in the ileum than in the jejunum.