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Objective: Pediatric acute liver failure (PALF) is a heterogeneous, rare, and severe condition, which outcome is survival due to liver spontaneous recovery or death. The patients who do not recover may be allocated to liver transplantation, which is the standard treatment. This study aimed to build a prognostic model to support the clinical decision to indicate liver transplantation for patients with PALF in a Brazilian center. Methods: The authors retrospectively analyzed the clinical variables of 120 patients in the liver transplantation program of the 'Children's Institute of the University of São Paulo, Brazil. The authors conducted a univariate analysis of variables associated with survival in PALF. Logistic multivariate analysis was performed to find a prognostic model for the outcome of patients with pediatric acute liver failure. Results: Risk factors were analyzed using univariate analysis. Two prognostic models were built using multiple logistic regression, which resulted in 2 models: model 1(INR/ALT) and model 2 (INR/Total bilirubin). Both models showed a high sensitivity (97.9%/96.9%), good positive predictive value (89.5%/90.4%), and accuracy (88.4%/88.5%), respectively. The receiver operating characteristic was calculated for both models, and the area under the curve was 0.87 for model 1 and 0.88 for model 2. The Hosmer-Lemeshow test showed that model 1 was good. Conclusion: The authors built a prognostic model for PALF using INR and ALT that can contribute to the clinical decision to allocate patients to liver transplantation.

ABSTRACT Objective: To describe the incidence and to analyze risk factors associated with cholestasis in neonates with gastroschisis. Methods: This is a retrospective cohort study in a tertiary single center analyzing 181 newborns with gastroschisis between 2009 and 2020. The following risk factors associated with cholestasis were analyzed: gestational age, birth weight, type of gastroschisis, silo closure or immediate closure, days of parenteral nutrition, type of lipid emulsion, days of fasting, days to reach a full diet, days with central venous catheter, presence of infections, and outcomes. Results: Among the 176 patients evaluated, 41 (23.3%) evolved with cholestasis. In the univariate analysis, low birth weight (p=0.023), prematurity (p

Background: In pediatric liver transplantation, the optimal size of the transplanted liver ranges between 0.8% and 4.0% of the recipient’s weight. Sometimes, the graft weight exceeds this upper limit, characterizing the large-for-size condition potentially associated with reduced blood flow and worsening of ischemia-reperfusion injury. Therefore, it would be beneficial to increase the portal flow through arterialization of the portal vein. Materials and methods: Fifteen pigs underwent large-for-size liver transplants. They were divided into two groups: control (CTRL 6 animals – conventional technique) and arterialization – a shunt was established between the portal vein and the splenic artery (ART 9 animals). Hemodynamic, biochemical, histological, and molecular variables were compared. Results: Arterialization resulted in a significant increase in portal vein pressure but no changes in other hemodynamic variables, as shown in the analysis of variance. It was observed lower ALT values (p = 0.007), with no differences regarding the values of blood pH and lactate (p = 0.54 and p = 0.699 respectively) or histological variables (edema, steatosis, inflammation, necrosis, and IRI – p = 1.0, p = 0.943, p = 0.174, p = 0.832, p = 0.662, respectively). The molecular studies showed significantly increased expression of IL6 after 3 hours of reperfusion (p = 0.048) and decreased expression of ICAM immediately after reperfusion (p = 0.03). The regression analysis suggested a positive influence of portal flow and pressure on biochemical parameters. Conclusion: Arterialization of the portal vein showed no histological, biochemical, or molecular benefits in large-for-size transplantation.

Background 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.

Purpose 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.

Objectives: To analyze late-onset sepsis and to describe the etiological agents in newborns with gastroschisis. Methods: A retrospective cohort, including newborns with gastroschisis whose admissions occurred in the period between January 2012 to December 2018 in a tertiary referral center. Maternal and newborn characteristics, surgical procedures and evolution in hospitalization were verified. A bivariate analysis was performed with patients with proven late-onset neonatal sepsis and according to the simple or complex gastroschisis category, the prevalent microorganisms in positive cultures were identified, statistical tests were carried out and the significance level adopted was p < 0,05. Results are presented in proportions, averages and standard deviation or medians. The level of significance adopted was p < 0.05. Results: 101 newborns were analyzed, 45 (44.5%) were confirmed late-onset sepsis. The median birth weight was 2285+498 grams, and the gestational age was 35.9 +1.74weeks. The incidence of complex gastroschisis was 17.8%, the hospitalization time was 48.2+29.67 days and mortality was 9.9%. The newborns were divided into 2 groups: Group 1: late-onset sepsis (44.6%), and Group 2: no late-onset sepsis. The presence of complex gastroschisis was a factor associated with infection (p < 0.009). Fasting time (p < 0.001), parenteral nutrition time (p < 0.001), time to achieve full diet (p < 0.001), and hospitalization stay (p < 0.001) were higher in group 2. Gram-positive were the most frequent (51.1%), followed by Gram-negative (20%), and fungi (4.4%). Conclusions: Newborns with gastroschisis have a higher risk of evolving with late-onset sepsis, despite this study did not calculate the risk of sepsis statistically, and the main germs detected by cultures were gram-positive bacteria, specifically Staphylococcus epidermidis.

ABSTRACT BACKGROUND: Gastroschisis, especially complex type, prematurity and low birth weight are associated with a worse clinical outcome with higher mortality, higher incidence of sepsis and catheter-related infection, cholestasis, short bowel syndrome, greater number of days to achieve full diet, longer time of parenteral nutrition and longer hospitalization time. OBJECTIVE: To evaluate the growth of preterm newborns with gastroschisis during their hospitalization in the neonatal intensive care unit. METHODS: Descriptive study, based on a retrospective cohort (January 2012 to December 2018), including preterm newborns (gestational age less than 37 weeks) with simple and complex gastroschisis admitted in a tertiary neonatal intensive care unit. The following parameters were analyzed: maternal age, parity, type of delivery, birth weight, gender, gestational age, nutritional adequacy, type of gastroschisis, fasting time, parenteral nutrition time, time until achieving full enteral nutrition, hospitalization time, weight gain and outcome. The results were expressed in percentage, average, and median. RESULTS: A total of 101 newborns with gastroschisis were admitted, of which 59.4% were premature (80.7% of late preterm infants). From the maternal data, the mean age was 21.2 years and 68.3% were primiparous. Regarding childbirth: 80% were cesarean sections. From newborns: the average birth weight was 2137 g, 56.6% were female, the average gestational age was 34.8 weeks, the average weight gain was 20.8 g/day during hospitalization and 83.3% were discharged from the hospital. CONCLUSION: The growth analysis by weight gain (grams/day) during hospitalization in the intensive care unit showed that more than 90% of the sample presented acceptable or adequate weight gain.

Abstract To evaluate the ventricular function of patients with biliary atresia (BA) before and after liver transplantation using two-dimensional speckle tracking. Observational, analytical study with healthy control group, volunteers. We recruited patients from 0 to 18 years old who were candidates for liver transplantation and patients after six months of liver transplantation performed for BA from January 1997 to August 2015 at Children’s Institute of São Paulo University Medical School. The patients were submitted to a complete conventional echocardiographic study. After that, the images were captured for global longitudinal strain (GLS). A blood sample was collected for brain natriuretic peptide (BNP) level. Ejection fraction obtained by Simpson’s method was significantly higher in the hepatic pre-transplantation group (p

ABSTRACT Purpose: To evaluate the caliber of an arterial micro-anastomosis in the young growing animal using a continuous suture technique. Additionally, late morphological changes and blood flows distal to the anastomosis were evaluated. Methods: Seventy-four Wistar rats were submitted to laparotomy to access the aorta for blood flow measurement. The aorta was sectioned using microsurgery technique and an end-to-end anastomosis with continuous suture. After a period of six months to one year, the anastomosis was checked. Results: Regarding the size of the aortas, comparing the pre- and postoperative values, there was an increase of 13.33% in adult animals and 25% in young animals, without any difference in the blood flows. Conclusions: The arteries of young rats show signs of growth at the site of the anastomosis performed with continuous suture.

ABSTRACT Purpose: 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.

BACKGROUND: Even students with previous academic success may face challenges that affect their academic performance. Many medical schools offer programs to students at the risk of academic failure, to ensure that they succeed in the course. OBJECTIVE AND METHODS: In this report we describe a pioneering academic tutoring program developed at a Brazilian medical school and discuss the initial results of the program based on the feedback from tutors and data regarding the progression of students in the medical course. RESULTS: In 2018, 33 students enrolled into the program. Students' performance difficulties were mainly associated with mental health problems and socioeconomic vulnerability. Of the 33 students, 27 (81.8%) were assisted by the Mental Health Support Service and 16 (48.5%) were assisted by the Social Assistance Service. In addition to the planning academic activity class load, tutors were able to assist students in solving socioeconomic issues, carrying out personal support interventions with the promotion of self-esteem, and presenting suggestions for behavioral changes in their routine. For most students (72%), the action plan proposed by the tutors was successful. Eight of the 14 (57%) students in the fourth year progressed to the final two years of in-hospital practical training (internship). CONCLUSIONS: The Academic Tutoring Program showed positive results for most of the students. Close monitoring and tutor intervention allowed students with poor academic performance to overcome the low performance cycle. These important tasks demand time and energy from tutors, and institutional recognition of these professionals is essential for the successful maintenance of the program.

OBJECTIVES: 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, IL-10, 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

OBJECTIVE: To identify the best mode for diagnosing and treating the patients with choledochal cysts. METHODS: A retrospective study was performed with medical records of patients diagnosed with choledochal cysts from January 1994 to December 2017. In all cases, the diagnosis was based on ultrasound examination. All the patients underwent cyst resection and were divided in two groups: bile enteric anastomosis in the high portion of the common hepatic duct or in the dilated lower portion. RESULTS: Eighty-one cases were studied. The age of presentation was 4 y 2 mo ± 4 y 1 mo, and the age for the surgical treatment was 5 y 5 mo ± 4 y 6 mo. In 61 cases, US was the only image examination performed. There were 67 cases of Todani type I (82.7%), 13 cases of type IV (16.0%) and one case of type III (1.2%). Nine patients (29.0%) in the first period and 2 patients (4.0%) in the second period presented with postoperative complications (p=0.016). CONCLUSION: In patients with choledochal cysts, US is the only necessary diagnostic imaging. Performing the bile enteric anastomosis in the lower portion of the common hepatic duct is safer and has a lower risk of complications.

Objective: To describe the incidence and to analyze risk factors associated with cholestasis in neonates with gastroschisis. Methods: This is a retrospective cohort study in a tertiary single center analyzing 181 newborns with gastroschisis between 2009 and 2020. The following risk factors associated with cholestasis were analyzed: gestational age, birth weight, type of gastroschisis, silo closure or immediate closure, days of parenteral nutrition, type of lipid emulsion, days of fasting, days to reach a full diet, days with central venous catheter, presence of infections, and outcomes. Results: Among the 176 patients evaluated, 41 (23.3%) evolved with cholestasis. In the univariate analysis, low birth weight (p=0.023), prematurity (p<0.001), lipid emulsion with mediumchain triglycerides and long-chain triglycerides (p=0.001) and death (p<0.001) were associated with cholestasis. In the multivariate analysis, patients who received lipid emulsion with fish oil instead of medium chain triglycerides/long chain triglycerides (MCT/LCT) emulsion had a lower risk of cholestasis. Conclusions: Our study shows that lipid emulsion with fish oil is associated with a lower risk of cholestasis in neonates with gastroschisis. However, this is a retrospective study and a prospective study should be performed to confirm the results. [ABSTRACT FROM AUTHOR]

Abstract Background 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.

OBJECTIVE: Chronic rejection remains a major cause of graft failure with indication for re-transplantation. The incidence of chronic rejection remains high in the pediatric population. Although several risk factors have been implicated in adults, the prognostic factors for the evolution and reversibility of chronic rejection in pediatric liver transplantation are not known. Hence, the current study aimed to determine the factors involved in the progression or reversibility of pediatric chronic rejection by evaluating a series of chronic rejection cases following liver transplantation. METHODS: Chronic rejection cases were identified by performing liver biopsies on patients based on clinical suspicion. Treatment included maintaining high levels of tacrolimus and the introduction of mofetil mycophenolate. The children were divided into 2 groups: those with favorable outcomes and those with adverse outcomes. Multivariate analysis was performed to identify potential risk factors in these groups. RESULTS: Among 537 children subjected to liver transplantation, chronic rejection occurred in 29 patients (5.4%). In 10 patients (10/29, 34.5%), remission of chronic rejection was achieved with immunosuppression (favorable outcomes group). In the remaining 19 patients (19/29, 65.5%), rejection could not be controlled (adverse outcomes group) and resulted in re-transplantation (7 patients, 24.1%) or death (12 patients, 41.4%). Statistical analysis showed that the presence of ductopenia was associated with worse outcomes (risk ratio=2.08, p=0.01). CONCLUSION: The presence of ductopenia is associated with poor prognosis in pediatric patients with chronic graft rejection.

Abstract Objective: Surgical treatment of anorectal malformations (ARMs) and Hirschsprung's disease (HD) leads to alterations in bowel habits and fecal incontinence, with consequent quality of life impairment. The objectives were to create and validate a Questionnaire for the Fecal Incontinence Index (FII) based on the Holschneider score, as well as a Questionnaire for the Assessment of Quality of Life Related to Fecal Incontinence in Children and Adolescents (QQVCFCA), based on the Fecal Incontinence Quality of Life. Methods: The questionnaires were applied to 71 children submitted to surgical procedure, in two stages. Validity was tested by comparing the QQVCFCA and a generic quality of life questionnaire (SF-36), and between QQVCFCA and the FII. A group of 59 normal children was used as control. Results: At two stages, 45.0% (32/71) and 42.8% (21/49) of the patients had fecal incontinence. It was observed that the QQVCFCA showed a significant correlation with the SF-36 and FII (Pearson's correlation 0.57), showing that the quality of life is directly proportional to improvement in fecal incontinence. Quality of life in patients with fecal incontinence is still globally impaired, when compared with control subjects (p

. Background and Objectives: Cirrhosis is a liver disease that causes about one million deaths annually worldwide. The estimated cirrhosis prevalence ranges from 4.5−9.5% in the general population. Up to 40% of cirrhotic patients are asymptomatic and may be diagnosed late. Studies have described the importance of the functions of the liver and autonomic nervous system (ANS) and their relationship. There is limited information available on non-alcoholic cirrhosis and heart rate variability (HRV), which is a measure of the ANS. This study aimed to evaluate cardiac autonomic modulation through HRV in non-alcoholic cirrhosis individuals reported in previous observational and clinical trial studies. Materials and Methods: We performed a systematic review according to the Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) statement using the Medline, Scopus, and Web of Science electronic databases. Five studies were identified and reviewed. Results: HRV was decreased in patients with non-alcoholic cirrhosis, even in the first stage. Conclusions: HRV could be used as a complementary method to improve both the diagnosis and prognosis of non-alcoholic cirrhosis.

OBJECTIVES: 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

OBJECTIVE: The prognosis of patients with biliary atresia undergoing Kasai portoenterostomy is related to the timing of the diagnosis and the indication for the procedure. The purpose of the present study is to present a practical flowchart based on 257 children who underwent Kasai portoenterostomy. METHODS: We conducted a retrospective cohort study of patients who underwent Kasai portoenterostomy between 1981 and 2016. RESULTS: During the first period (1981 to 2009), 230 infants were treated, and the median age at the time of surgery was 84 days; jaundice was resolved in 77 patients (33.5%). During the second period, from 2010 to 2016, a new diagnostic approach was adopted to shorten the wait time for portoenterostomy; an ultrasonography examination suggestive of the disease was followed by primary surgical exploration of the biliary tract without complementary examination or liver biopsy. Once the diagnosis of biliary atresia was confirmed, a portoenterostomy was performed during the same surgery. During this period, 27 infants underwent operations; the median age at the time of surgery was 66 days (p

OBJECTIVE: The aim of this study was to summarize the experience of a tertiary center in treating hepatoblastoma for the last 21 years. PATIENTS AND METHODS: Fifty-eight cases were included. The tumor extent and prognosis were assessed using the PRETEXT system. The following data were analyzed: age at diagnosis, comorbidities, prematurity, treatment modalities, histopathological findings, surgical details and complications, treatment outcomes, chemotherapy schedules, side effects and complications. Treatment outcomes included the occurrence of local or distant recurrence, the duration of survival and the cause of death. The investigation methods were ultrasonography, CT scan, serum alpha-fetoprotein level measurement and needle biopsy. Chemotherapy was then planned, and the resectability of the tumor was reevaluated via another CT scan. RESULTS: The mean numbers of neoadjuvant cycles and postoperative cycles of chemotherapy were 6±2 and 1.5±1.7, respectively. All children except one were submitted for surgical resection, including 50 partial liver resections and 7 liver transplantations. Statistical comparisons demonstrated that long-term survival was associated with the absence of metastasis ( p= 0.04) and the type of surgery (resection resulted in a better outcome than transplantation) ( p= 0.009). No associations were found between vascular invasion, incomplete resection, histological subtype, multicentricity and survival. The overall 5-year survival rate of the operated cases was 87.7%. CONCLUSION: In conclusion, the experience of a Brazilian tertiary center in the management of hepatoblastoma in children demonstrates that long survival is associated with the absence of metastasis and the type of surgery. A multidisciplinary treatment involving chemotherapy, surgical resection and liver transplantation (including transplantations using tissue from living donors) led to good outcomes and survival indexes.

OBJECTIVE: Intestinal ischemia-reperfusion injury occurs in several clinical conditions and after intestinal transplantation. The aim of the present study was to investigate the phenomena of apoptosis and cell proliferation in a previously described intestinal ischemia-reperfusion injury autograft model using immunohistochemical markers. The molecular mechanisms involved in ischemia-reperfusion injury repair were also investigated by measuring the expression of the early activation genes c-fos and c-jun, which induce apoptosis and cell proliferation. MATERIALS AND METHODS: Thirty adult male Wistar rats were subjected to surgery for a previously described ischemia-reperfusion model that preserved the small intestine, the cecum and the ascending colon. Following reperfusion, the cecum was harvested at different time points as a representative segment of the intestine. The rats were allocated to the following four subgroups according to the reperfusion time: subgroup 1: 5 min; subgroup 2: 15 min; subgroup 3: 30 min; and subgroup 4: 60 min. A control group of cecum samples was also collected. The expression of c-fos, c-jun and immunohistochemical markers of cell proliferation and apoptosis (Ki67 and TUNEL, respectively) was studied. RESULTS: The expression of both c-fos and c-jun in the cecum was increased beginning at 5 min after ischemia-reperfusion compared with the control. The expression of c-fos began to increase at 5 min, peaked at 30 min, and exhibited a declining tendency at 60 min after reperfusion. A progressive increase in c-jun expression was observed. Immunohistochemical analyses confirmed these observations. CONCLUSION: The early activation of the c-fos and c-jun genes occurred after intestinal ischemia-reperfusion injury, and these genes can act together to trigger cell proliferation and apoptosis.

OBJECTIVE: In most cases of pediatric liver transplantation, the clinical scenario of large-for-size transplants can lead to hepatic dysfunction and a decreased blood supply to the liver graft. The objective of the present experimental investigation was to evaluate the effects of ischemic preconditioning on this clinical entity. METHODS: Eighteen pigs were divided into three groups and underwent liver transplantation: a control group, in which the weights of the donors were similar to those of the recipients, a large-for-size group, and a large-for-size + ischemic preconditioning group. Blood samples were collected from the recipients to evaluate the pH and the sodium, potassium, aspartate aminotransferase and alanine aminotransferase levels. In addition, hepatic tissue was sampled from the recipients for histological evaluation, immunohistochemical analyses to detect hepatocyte apoptosis and proliferation and molecular analyses to evaluate the gene expression of Bax (pro-apoptotic), Bcl-XL (anti-apoptotic), c-Fos and c-Jun (immediate-early genes), ischemia-reperfusion-related inflammatory cytokines (IL-1, TNF-alpha and IL-6, which is also a stimulator of hepatocyte regeneration), intracellular adhesion molecule, endothelial nitric oxide synthase (a mediator of the protective effect of ischemic preconditioning) and TGF-beta (a pro-fibrogenic cytokine). RESULTS: All animals developed acidosis. At 1 hour and 3 hours after reperfusion, the animals in the large-for-size and large-for-size + ischemic preconditioning groups had decreased serum levels of Na and increased serum levels of K and aspartate aminotransferase compared with the control group. The molecular analysis revealed higher expression of the Bax, TNF-alpha, I-CAM and TGF-beta genes in the large-for-size group compared with the control and large-for-size + ischemic preconditioning groups. Ischemic preconditioning was responsible for an increase in c-Fos, IL-1, IL-6 and e-NOS gene expression. CONCLUSION: Ischemia-reperfusion injury in this model of large-for-size liver transplantation could be partially attenuated by ischemic preconditioning.

In the last 25 years, liver transplantation in children has become an effective, definitive, and universally accepted treatment for terminal liver diseases. Long-term survival exceeds 80% and improves each year as the result of constant technical advancements and improvements in immediate postoperative intensive care and clinical control.