ABSTRACT
Solid pseudopapillary tumors of the pancreas are usually described as rare lesionswith low malignant potential and unpredictable behavior. The prognosis may be favorableeven with local or distant dissemination. Despite the steady increase of cases diagnosed,the pathogenesis of this neoplasm remains unclear. We present a case of an incidentaltumor discovered because of an acute abdomen in a postpartum woman without previousevidence of a tumor during the pregnancy.
Subject(s)
Neoplasms, Cystic, Mucinous, and Serous , Pancreatic Neoplasms , PancreasABSTRACT
OBJETIVO: O estresse oxidativo é um importante mecanismo responsável pela disfunção dos enxertos após transplante de fígado (TF). Sabe-se que níveis baixos de Glutationa reduzida (GSH) deixam os enxertos vulneráveis aos danos de reperfusão. O objetivo deste estudo foi avaliar as concentrações de GSH e da Glutationa oxidada (GSSG), os danos hepatocelulares e a função em enxertos ótimos e subótimos após TF. MÉTODOS: Foram realizadas biópsias em 33 pacientes imediatamente antes do implante e duas horas após a reperfusão, permitindo a determinação do GSH, GSSG e o cálculo do índice de stress oxidativo (GSH/GSSG). Foram medidas as transaminases hepáticas e as atividades da Protrombina (TP) e do Fator V para avaliação dos danos hepatocelulares e da função do enxerto, respectivamente. O dano histopatológico foi avaliado através de um índice de cinco parâmetros. RESULTADOS: Houve uma diminuição nos níveis de GSH (p<0.01) 0.323 ± 0.062 ìmol/g to 0.095 ± 0.01 ìmol/g and 0.371 ± 0.052 ìmol/g to 0.183 ± 0.046 ìmol/g) e aumento nos níveis de GSSG (0.172 ± 0.038 ìmol/g to 0.278 ± 0.077 ìmol/g and 0.229 ± 0.048 ìmol/g to 0.356 ± 0.105 ìmol/g) (p<0.05). Houve diminuição do GSH/GSSG (2.23 ± 0.31 to 0.482 ± 0.042 and 2.47 ± 0.32 to 0.593 ± 0.068). Nenhuma diferença entre os grupos ótimo e subótimo foi vista após duas horas de reperfusão. Os escores de danos histopatológicos foram maiores no grupo subótimo (6.46 ± 0.4 vs. 5.39 ± 1.1) (p<0.05) e mostraram correlação com o TP e fator V no grupo Ótimo (p<0.05). A análise multivariada apontou a esteatose como um fator de risco independente para a ocorrência de danos histopatológicos (p<0.05). CONCLUSÃO: Houve uma significativa depleção de GSH e formação de GSSG após a preservação em solução devido a um intenso estresse oxidativo nos enxertos ótimos e subótimos, porém estes níveis não se correlacionaram com a viabilidade dos enxertos.
Subject(s)
Humans , Male , Female , Adult , Middle Aged , Glutathione Disulfide/metabolism , Glutathione/metabolism , Hepatocytes/metabolism , Liver Transplantation/physiology , Oxidative Stress/physiology , Reperfusion Injury/physiopathology , Biopsy , Graft Survival/physiology , Hepatocytes/pathology , Liver Transplantation/pathology , Liver/pathology , Multivariate Analysis , Organ Preservation , Reperfusion Injury/metabolism , Reperfusion Injury/pathology , Statistics, NonparametricABSTRACT
PURPOSE: The oxidative stress is an important mechanism responsible for dysfunction after orthotopic liver transplantation (OLT). Glutathione (GSH) low levels after cold storage render the grafts vulnerable to reperfusion injury. Aim of this study was to evaluate GSH and oxidized glutathione (GSSG) liver concentrations, the hepatocellular injury and function in optimal and suboptimal grafts after human OLT. METHODS: Liver biopsies were taken in 33 patients before the implant and two hours after reperfusion, allowing determination of GSH, GSSG and oxidative stress ratio (GSH/GSSG). Serum transaminases, prothrombin activity (PT) and factor V were measured to evaluate injury and function respectively. Histopathological injury was analyzed by an index of five parameters. RESULTS: There was a decrease in GSH (p<0.01) after reperfusion (0.323 +/- 0.062 ìmol/g to 0.095 +/- 0.01 ìmol/g and 0.371 +/- 0.052 ìmol/g to 0.183 +/- 0.046 ìmol/g) in suboptimal and optimal groups, respectively. An increase of GSSG (p<0.05) occurred after reperfusion (0.172 +/- 0.038 ìmol/g to 0.278 +/- 0.077 ìmol/g and 0.229 +/- 0.048 ìmol/g to 0.356 +/- 0.105 ìmol/g) in suboptimal and optimal groups, respectively. A decrease (p<0.01) occurred in the GSH/GSSG ratio after reperfusion (2.23 +/- 0.31 to 0.482 +/- 0.042 and 2.47 +/- 0.32 to 0.593 +/- 0.068) in suboptimal and optimal groups, respectively. Histopathological injury scores were higher (p<0.05) in the suboptimal group than in optimal (6.46 +/- 0.4 vs. 5.39 +/- 1.1) and showed correlation with PT and factor V in the optimal group (p<0.05). Multivariate analysis pointed steatosis as an independent risk factor to histopathological injury (p<0.05). CONCLUSION: There was a significant GSH depletion and GSSG formation after cold storage and reperfusion due to a similar oxidative stress in optimal and suboptimal grafts, but these levels were not related to graft viability.
