RESUMO Objetivo: Analisar a incidência e os fatores de risco associados à colestase em recém-nascidos com gastrosquise. Métodos: Estudo de coorte retrospectivo em um único centro terciário, que analisou 181 recém-nascidos com gastrosquise entre 2009 e 2020. Foram examinados os seguintes fatores de risco associados à colestase: idade gestacional, peso ao nascer, tipo de gastrosquise, fechamento com silo ou fechamento imediato, dias de uso nutrição parenteral, tipo de emulsão lipídica, dias de jejum, dias para atingir a dieta completa, dias com cateter venoso central, presença de infecções e desfechos. Resultados: Dos 176 pacientes avaliados, 41 (23,3%) evoluíram com colestase. Baixo peso ao nascer (p=0,023), prematuridade (p<0,001), emulsão lipídica com triglicerídeos de cadeia média e triglicerídeos de cadeia longa (p=0,001) e óbito (p<0,001) foram associados à colestase. Na análise multivariada, os pacientes que receberam emulsão lipídica com óleo de peixe em vez da emulsão diária de triglicérides de cadeia média/triglicérides de cadeia longa (MCT/LCT) apresentaram menor risco de colestase. Conclusões: Nosso estudo mostra que a emulsão lipídica com óleo de peixe está associada a menor risco de colestase em neonatos com gastrosquise, porém este é um estudo retrospectivo, e um estudo prospectivo deve ser realizado para confirmar os resultados. Objetivo recémnascidos recém nascidos Métodos terciário 18 200 2020 gestacional imediato parenteral jejum completa central desfechos Resultados 17 avaliados 4 23,3% 233 23 3 (23,3% p=0,023, p0023 p p=0,023 , 0 023 (p=0,023) p<0,001, p0001 p<0,001 001 p=0,001 (p=0,001 (p<0,001 multivariada médiatriglicérides MCT/LCT MCTLCT MCT LCT (MCT/LCT Conclusões resultados 1 20 202 23,3 2 (23,3 p002 p=0,02 02 (p=0,023 p000 p<0,00 00 p=0,00 (p=0,00 (p<0,00 23, (23, p00 p=0,0 (p=0,02 p<0,0 (p=0,0 (p<0,0 (23 p0 p=0, p<0, (p=0, (p<0, (2 p=0 p<0 (p=0 (p<0 ( p= p< (p= (p< (p

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<0.001), lipid emulsion with medium-chain 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. Objective Methods 18 200 2020 analyzed age nutrition fasting diet catheter infections outcomes Results 17 evaluated 4 23.3% 233 23 3 (23.3% analysis p=0.023, p0023 p p=0.023 , 0 023 (p=0.023) p<0.001, p0001 p<0.001 001 mediumchain longchain long p=0.001 (p=0.001 (p<0.001 triglycerideslong MCT/LCT MCTLCT MCT LCT (MCT/LCT Conclusions However results 1 20 202 23.3 2 (23.3 p002 p=0.02 02 (p=0.023 p000 p<0.00 00 p=0.00 (p=0.00 (p<0.00 23. (23. p00 p=0.0 (p=0.02 p<0.0 (p=0.0 (p<0.0 (23 p0 p=0. p<0. (p=0. (p<0. (2 p=0 p<0 (p=0 (p<0 ( p= p< (p= (p< (p

ABSTRACT Purpose: 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. Conclusions: IPoC methods positively reduced the damage caused by IRI in weaning rats. Purpose AMI (AMI death (IPoC revascularization model Methods Thirtytwo Thirty two 21dayold dayold 21 day old performed control ischemiareperfusion reperfusion IRI, , (IRI) LIPoC (LIPoC RIPoC. RIPoC . (RIPoC) euthanasia liver lungs analyses Results duodenum intestines method ileum proapoptotic (proapoptotic BclXL Bcl XL antiapoptotic (antiapoptotic Conclusions 2 (IRI (RIPoC

Abstract Background: Hirschsprung’s Disease (HD) is characterized by intestinal sub-occlusion and the absence of enteric ganglion cells. A rectal biopsy examination is performed to confirm the diagnosis. In a recent study, we demonstrated that the analysis of 60 sections of rectal mucosa and submucosa stained by H&E may ensure a 90% diagnostic accuracy. Although the need to analyze so many sections makes the process of reading the slides more time-consuming, this encouraged us to study their distribution in the healthy rectal submucosa, to simplify the diagnosis. Objectives: To develop a method that facilitates HD diagnosis by studying the distribution of ganglion cells in the submucosal plexus. Methods: Using the calretinin technique, we studied the distribution of plexuses in 60 fragments of rectal submucosa from 19 cadavers. After the study, the reading method created was used for diagnosis in 47 cases of suspected HD, using H&E staining. The accuracy was verified by comparing the results obtained with H&E to those obtained with the acetylcholinesterase technique, the golden standard in our laboratory. Results: The study of submucosal plexus distribution showed that just by examining the submucosal region every 20 µm, approximately, it is possible to locate a ganglionic plexus, and we have already been able to diagnose HD with 93% accuracy. Conclusion: The study of ganglion cell distribution enabled the creation of a simplified method for reading the slides. The method applied achieved good accuracy and it can be used as an alternative method in HD diagnosis. Background Hirschsprungs Hirschsprung s (HD subocclusion sub occlusion 6 HE H E 90 timeconsuming, timeconsuming time consuming, consuming time-consuming Objectives Methods technique 1 cadavers 4 staining laboratory Results 2 µm approximately 93 Conclusion 9

Abstract 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 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: Incisional hernias are more frequent in adults than in children. It is hypothesized that a more efficient healing process in pediatric patients could explain this difference in incidence. Certain elements of healing such as neovascularization, degree of inflammation, percentage of mature and immature collagen, the proliferation of fibroblasts, and expression of certain genes could explain why healing in children is more efficient when compared to the adult and elderly populations. Materials and methods: Seventy-one rats of 3 different age groups (weaning, adult, and old) underwent surgery with 3 different incisions (vertical, oblique, and horizontal). During the procedure, the skin and abdominal wall of the animal were sectioned and only the skin was sutured to mimic incisional hernia in the animals. Four weeks after surgery, the rats were euthanized, their skin was removed, and the extent of scar tissue formed in the muscle opening was measured. In addition, samples of the scar tissue were collected for histological, immunohistochemical, and molecular analyzes. Nine rats served as controls. Results: Shorter-length hernias were formed in weaning rats when compared to old ones when the surgical incision was horizontal (p = 0.03). There was a greater proliferation of fibroblasts in rats in the younger age groups, regardless of the type of incision. The Lox gene was more expressed in weaning rats with vertical and oblique incisions. Conclusions: These differences could explain the better healing and lower incidence of hernias in the pediatric population, although this aspect requires further studies.

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.

Resumo O objetivo deste estudo foi relatar o uso de lock de etanol na profilaxia infecciosa de cateteres venosos de longa permanência em recém-nascidos com disfunção intestinal grave e dependentes de nutrição parenteral total e prolongada, internados em um Centro de Terapia Intensiva Neonatal (nível terciário) entre 2015 e 2020. Das 914 admissões, seis (0,65%) recém-nascidos preencheram os critérios de inclusão. A mediana da idade da passagem do cateter foi de 121,5 dias, sendo dois cateteres PowerPicc (PICC Power Sinergy™, São Paulo), um cateter Groshong (Groshong™ Central Venous Catheter BD, São Paulo) e três cateteres de silicone, todos tunelizados. O tempo de permanência apresentou mediana de 182,5 dias. Cinco pacientes apresentaram pelo menos um episódio de infecção associada ao cateter venoso central, sendo isolados agentes Gram-positivos, negativos e fungos. A mediana de dias de internação foi de 555, e a mortalidade, 33,3%. O lock de etanol não apresentou efeitos colaterais e foi relativamente eficaz na prevenção de infecções relacionadas ao cateter venoso central.

Abstract The aim of this study was to report on use of ethanol lock in long-term catheters in newborns with severe intestinal dysfunction, dependent on total and prolonged parenteral nutrition, in a Neonatal Intensive Care Center (tertiary level), between 2015 and 2020. Six infants (0.65%) out of the 914 admitted during the period met the inclusion criteria. The median age at catheter placement was 121.5 days. Two Powerpicc (PICC Power Sinergy™, São Paulo), one Groshong (Groshong™ Central Venous Catheter BD, São Paulo), and three silicone catheters were used, all tunneled, and the median dwell duration was 182.5 days. Four patients had at least one episode of infection related to the central venous catheter, and Gram-positive, Gram-negative, and fungal agents were isolated. The median length of hospital stay was 555 days and mortality was 33.3%. The ethanol lock did not cause any side effects and was relatively effective in preventing infections related to the central venous catheter.

RESUMO CONTEXTO: Gastrosquise, principalmente o tipo complexo, prematuridade e baixo peso ao nascer estão associados a um pior desfecho clínico com maior mortalidade, maior incidência de sepse e infecção relacionada ao cateter, colestase, síndrome do intestino curto, maior número de dias para atingir dieta plena, maior tempo de nutrição parenteral e maior tempo de internação. OBJETIVO: Avaliar o crescimento de recém-nascidos pré-termo com gastrosquise durante sua internação na unidade de terapia intensiva neonatal. MÉTODOS: Estudo descritivo, baseado em uma coorte retrospectiva (janeiro de 2012 a dezembro de 2018), incluindo recém-nascidos pré-termo (idade gestacional inferior a 37 semanas) com gastrosquise simples e complexa, admitidos em uma unidade de terapia intensiva neonatal de nível terciário. Foram analisados: idade materna, paridade, tipo de parto, peso de nascimento, gênero, idade gestacional, adequação nutricional, tipo de gastrosquise, tempos de jejum, de nutrição parenteral, até atingir nutrição enteral plena e de internação, ganho de peso e desfecho. Os resultados estão expressos em porcentagem, médias e medianas. RESULTADOS: Foram admitidos 101 recém-nascidos com gastrosquise, dos quais 59,4% eram prematuros (80,7% prematuros tardios). Dos dados maternos, a idade média foi de 21,2 anos e 68,3% eram primigestas. Com relação ao parto: 80% foram cesarianas. Dos recém-nascidos: o peso médio de nascimento foi de 2137 g, 56,6% eram do sexo feminino, a idade gestacional média foi de 34,8 semanas, o ganho médio de peso de 20,8 g/dia durante a internação e 83,3% receberam alta hospitalar. CONCLUSÃO: A análise do crescimento por meio de ganho de peso (gramas/dia) durante a internação na unidade de terapia intensiva mostrou que mais de 90% da amostra apresentou ganho aceitável ou adequado de peso.

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 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.

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.

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<0.0001). CONCLUSION: The model is feasible and may be utilized in studies on liver cirrhosis and infection in growing animals.