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PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO COORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIOR PROGRAMA DE EXCELENCIA ACADEMICA Este trabalho apresenta a utilização de métodos de equilíbrio limite em conjunto com métodos numéricos pela abordagem probabilística, para avaliação da estabilidade de uma barragem de rejeitos de mineração de ferro situada no quadrilátero ferrífero, no Estado de Minas Gerais. Foram conduzidas análises fazendo uso dos métodos de Bishop Simplificado (1955) e Morgenstern e Price (1965), além de análises numéricas de tensão vs deformação pelo método dos elementos finitos. Os campos de poropressão gerados no modelo numérico em dois momentos distintos da obra foram exportados para os modelos de equilíbrio limite, de forma que ambas análises fossem realizadas em condições piezométricas similares. Para as análises probabilísticas foram adotados os métodos FOSM (First Order Second Moment) e Monte Carlo. São apresentandos os conceitos básicos de análises de estabilidade determinísticas e probabilísticas, abrangendo os métodos de cálculo de FS, fundamentos de probabilidade e estatística e conceitos de modelagem numérica. Este estudo aborda também os princípios construtivos de barragens de rejeito de mineração, além da aplicação dos métodos probabilísticos para avaliação da estabilidade de uma barragem de rejeitos, construída pelo método de jusante. Os resultados indicaram que a consideração de uma superfície de ruptura livre foi fator preponderante na influência dos parâmetros na PR (Probabilidade de Ruptura). Concluiu-se também que os método de cálculo de FS teve maior influência no valor da PR do que as condições piezométricas da fundação. This work presents the use of limit equilibrium (LEM) and numerical methods by the probabilistic approach, in order to evaluate the stability of an iron ore tailings dam located in Minas Gerais s iron quadrangle. LEM analyzes were carried out using the Simplified Bishop (1955) and Morgenstern and Price (1965) methods, in addition to stress vs strain analyzes with the finite element method. The pore pressure fields generated in the numerical model at two distinct construction stages were exported to the limit equilibrium models in order to guarantee that both analyzes were performed on the same piezometric conditions. For the probabilistic analyzes the FOSM (First Order Second Moment) and Monte Carlo methods were applied. The basic concepts of deterministic and probabilistic stability analysis are presented together with the fundamentals of statistics and probability, FoS (Factor of Safety) calculation methods, as well as numerical modeling concepts. This work also addresses the definition and construction principles of tailings dams. This study presents an application of probabilistic methods to assess the stability of a tailings dam built and heightened by the downstream method. The results indicate that the consideration of a free failure surface was the decisive factor to the magnitude of the influence of each parameter on the PF (Probability of Failure). It was also concluded that the FoS calculation methods had a greater influence on the PF than the foundation s piezometric conditions.

Introdução: A fluoresceína sódica (FS) é um corante, do tipo xanteno, utilizado no campo cirúrgico tanto para procedimentos oftalmológicos quanto neurocirúrgicos; neste último caso atualmente sendo aplicado à delimitação de barreira hematoencefálica (BHE) em caso de rompimento desta por diversos tipos de tumores cerebrais, como os gliomas. Objetivo: Realizar uma revisão da literatura sobre os usos clínicos da fluoresceína na prática médica. Método: Foi realizado um levantamento bibliográfico nas bases de dados Scielo e Lilacs com a ferramenta computacional Publish or Perish. Resultados: O uso da fluoresceína sódica se mostrou eficaz no processo de ressecção tumoral total (GTR) dos tumores cerebrais com boa margem de segurança e alta especificidade, graças a seu alto potencial de acúmulo nas regiões de ruptura de BHE e delimitação de região tumoral com precisão. Conclusão: O uso da fluoresceína sódica pode ser empregado tanto na oftalmologia quanto na neurocirurgia.

Early diagnosis of neurofibromatosis is significant to start the multidisciplinary approach of this type of patient. This syndrome may be first identified in pediatric dental care. This study is about a 9-year-old patient who was diagnosed with neurofibromatosis type 1 from a plexiform neurofibroma displayed in the left hemi-maxilla. From the microscopic diagnosis of the lesion the investigation of other related injuries began, according to the diagnostic criteria of the National Institute of Health (NIH), leading to the diagnosis of systemic alterations. The parental awareness about the condition and the establishment of multidisciplinary care are important for the treatment to be more conservative and the patient has fewer complications with better quality of life. The use of the diagnostic criteria in this case shows how methodization is important for reaching more accurate and reliable diagnoses.

AIM To compare gallstones removal rate and incidence of bleeding, pancreatitis, use of mechanical lithotripsy, cholangitis and perforation between isolated sphincterotomy vs sphincterotomy associated with balloon dilation of papilla in choledocholithiasis through the meta-analysis of randomized clinical trials. METHODS We conducted a systematic review according to the PRISMA guidelines. Literature search was restricted to randomized controlled trials (RCTs) on MedLine, Cochrane Library, LILACS, and EMBASE database platforms in July 2017. The manual search included references of retrieved articles. We extracted data focusing on outcomes: The primary endpoint was the stones removal rate; Secondary endpoints were rates of pancreatitis, bleeding, use of mechanical lithotripsy (ML), perforation and cholangitis. RESULTS Eleven RCTs with 1824 patients were included. EST was associated with more post-endoscopic retrograde cholangiopancreatography (ERCP) bleeding [FE RD-0.02, CI (-0.03, -0.00), I2 = 33%, P = 0.05] and more need of mechanical lithotripsy in general [RE RD-0.16, CI (-0.25, -0.06), I2 = 90%, P = 0.002] and in subgroup analysis of stones greater than 15 mm [RE RD-0.20, CI (-0.38, -0.02), I2 = 82%, P = 0.003]. Incidence of pancreatitis [FE RD-0.01, CI (-0.03, 0.01), I2 = 0, P = 0.36], cholangitis [FE RD-0.00, CI (-0.01, 0.01), I2 =0, P = 0.97] and perforation [FE RD-0.01, CI (-0.01, 0.00), I2 = 0, P = 0.23] was similar between the groups as well as similar stone removal rates in general [FE RD-0.01, CI (-0.01, 0.04), I2 = 0, P = 0.23] and pooled analysis of stones greater than 15 mm [FE RD-0.02, CI (-0.02, 0.07), I2 = 11%, P = 0.31]. CONCLUSION Through meta-analysis of randomized clinical trials we found that isolated sphincterotomy was associated with more post-ERCP bleeding and more need for mechanical lithotripsy. However, there was no statistical difference in the stone removal rate between isolated sphincterotomy and sphincterotomy associated with balloon dilation in the approach to remove gallstones.

AIM To compare the cannulation success, biochemical profile, and complications of the papillary fistulotomy technique vs catheter and guidewire standard access. METHODS From July 2010 to May 2017, patients were prospectively randomized into two groups: Cannulation with a catheter and guidewire (Group I) and papillary fistulotomy (Group II). Amylase, lipase and C-reactive protein at T0, as well as 12 h and 24 h after endoscopic retrograde cholangiopancreatography, and complications (pancreatitis, bleeding, perforation) were recorded. RESULTS We included 102 patients (66 females and 36 males, mean age 59.11 ± 18.7 years). Group I and Group II had 51 patients each. The successful cannulation rates were 76.5% and 100%, respectively (P = 0.0002). Twelve patients (23.5%) in Group I had a difficult cannulation and underwent fistulotomy, which led to successful secondary biliary access (Failure Group). The complication rate was 13.7% (2 perforations and 5 mild pancreatitis) vs 2.0% (1 patient with perforation and pancreatitis) in Groups I and II, respectively (P = 0.0597). CONCLUSION Papillary fistulotomy was more effective than guidewire cannulation, and it was associated with a lower profile of amylase and lipase. Complications were similar in both groups.

Objectives The aim of the study was to evaluate the role of early endoscopic retrograde cholangiopancreatography (ERCP) in the treatment of acute biliary pancreatitis, in comparison with conservative treatment. Methods Systematic review via databases (MEDLINE [PubMed], Latin-American and Caribbean Health Sciences Literature database, Embase, Cochrane Central, and the [Brazilian] Regional Library of Medicine) is conducted. We analyzed 10 randomized controlled trials (1091 patients). Outcomes were the following: local and systemic adverse events; acute cholangitis; death; length of hospital stay; cost; abdominal pain; and time to a reduction in body temperature. For the meta-analysis, we used risk difference (RD) and mean with standard deviation as measures of variability. Results There was a statistically significant difference between the patients submitted to ERCP in terms of the following: local adverse events (RD, 0.74; 95% confidence interval [CI], 0.55-0.99), time to pain relief and time to a reduction in axillary temperature (RD, -5.01; 95% CI, -6.98 to -3.04, and RD, -1.70; 95 CI%, -2.33 to -1.08, respectively). Patients undergoing ERCP spent less time in hospital (RD, -11.04; 95% CI, -15.15 to -6.93). Cost was lower in the group treated with ERCP. Conclusions Early ERCP decreases local adverse events, shortening the time to pain relief, to a reduction in axillary temperature, hospital stays, and cost in patients with acute biliary pancreatitis.