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Fugit irreparabile tempus: “foge irreparavelmente o tempo" (Virgílio).

ABSTRACT Introduction: Artificial intelligence systems are promising health care technologies, mainly in medical subareas such as pathology, and can be used as support methods for the histological diagnosis of mammary nodules. Objective: This study describes the method and results of the development of artificial intelligence software for the histopathological analysis of mammary nodules. Methods: The software was developed by using two neural networks - Inception and MobileNet. The database used for learning the conditions analyzed (histologically normal breast, fibroadenoma, fibrocystic changes, in situ ductal carcinoma, invasive carcinoma of no special type and invasive lobular carcinoma) was obtained after authorization of the Path Presenter site with 5,298 images. The 2,740 images used for the validation of the system were obtained from the Pathology Institute of Passo Fundo. Results: The present software had sensitivity of 80.5% [95% confidence interval (CI), 71.9%-89.1%] and specificity of 96.1% (95% CI, 94.3%-97.8%) for MobileNet and sensitivity of 73.8% (95% CI, 52.6%-115%) and specificity of 94.7% (CI 95%, 91.7%-97.7%) for Inception. For the differentiation of malignant conditions, it obtained a maximum sensitivity of 78.7% and specificity of 95.8%; for differentiation of benign conditions, the maximum sensitivity was 82.6% and the specificity was 97.4%. Conclusion: The present software presented promising results in the histopathological analysis of mammary nodules. It reinforced the idea that in the future the presence of diagnostic support systems in breast pathologies may play a crucial role in health care.

­­Introdução: A inteligência artificial (IA) está revolucionando a área da saúde. Na oftalmologia, esta tecnologia pode possibilitar diagnósticos mais rápidos e precisos, impedindo a progressão das alterações na visão. Médicos e algoritimosalgoritmos podem ser mais eficientes quando trabalham juntos. Desenvolver um software de IA com alta especificidade e sensibilidade para apoio no diagnóstico de algumas patologias oftalmológicas. Métodos: O software de deep learning foi construído através de redes neurais valendo de duas bases computacionais MobileNet e Inception. Para o treinamento do banco de dados foram utilizadas 2.520 imagens de glaucoma, retinopatia diabética, toxoplasmose ocular, papiledema, descolamento de retina e retina normal. Para a validação foi utilizado 428 imagens patológicas e normais para os cálculos de sensibilidade e de especificidade. Todas as imagens foram cedidas da Sociedade Americana de Especialistas da Retina. Resultados: Os resultados de sensibilidade e especificidade foram no MobileNet de 91% (IC 95%, 89-92%) e 98,5% (IC 95%, 98-99%); no Inception, de 91,4% (IC 95%, 89-93,5%) de 98,4% (IC 95%, 98-98,8%), respectivamente. Não houve diferença significativa entre os dois métodos utilizados. Conclusão: O software apresentou resultados promissores na distinção das condições oftalmológicas pesquisadas.

Introduction: Cutaneous neoplasms are the most common cancers in the world, and have high morbidity rates. A definitive diagnosis can only be obtained after histopathological evaluation of the lesions. Objective: To develop an artificial intelligence program to establish the histopathological diagnosis of cutaneous lesions. Methodology: A deep learning program was built using three neural network architectures: MobileNet, Inception and convolutional networks. A database was constructed using 2732 images of melanomas, basal and squamous cell carcinomas, and normal skin. The validation set consisted of 284 images from all 4 categories, allowing for the calculation of sensitivity and specificity. All images were provided by the Path Presenter website. Results: The sensitivity and specificity of the MobileNet model were 92% (95%CI, 83-100%) and 97% (95%CI, 90-100%), respectively; corresponding figures for the Inception model were 98.3% (95%CI, 86-100%) and 98.8% (95%CI, 98.2-100%); lastly, the sensitivity and specificity of the convolutional network model were 91.6% (95%CI, 73.8-100%) and 95.7% (95%CI, 94.4-97.2%). The maximum sensitivity for the differentiation of malignant conditions was 91%, and specificity was 95.4%. Conclusion: The program developed in the present study can efficiently distinguish between the main types of skin cancer with high sensitivity and specificity.

Ampliam-se o uso e a praticidade dos dispositivos móveis na vida das pessoas, tendo como características aparelhos cada vez mais robustos. Seguindo os avanços de hardware, o surgimento do Android marcou uma nova era na tecnologia móvel, abrindo as portas para novas possibilidades. Este artigo propõe a criação de uma interface personalizada para o Andróid, comparando-a com a versão de fábrica produzida por uma fabricante de renome no ramo de eletrônicos e apresenta as vantagens que podem se seguir em termos de eficiência e uso de recursos sem afetar o desempenho e nem a praticidade no uso do dispositivo.

The article offers information on the Portuguese Society of Digestive Endoscopy (SPED), which is aimed to promote the development and monitoring of training activities in the field of Digestive Endoscopy.

OBJETIVO: Avaliar a relação entre o padrão de uso da cocaína e a perfusão cerebral de dependentes da substância. MÉTODOS: Estudou-se uma amostra de 30 dependentes de cocaína por meio de tomografia computadorizada por emissão de fóton único (single photon emission computed tomography - SPECT) com hexametil-propileno-amina-oxima, marcada com tecnécio 99 m (99 m-Tc-HMPAO), e comparou-se o padrão de perfusão cerebral com o padrão de consumo da droga. RESULTADOS: Dos dependentes, 80% apresentaram alterações de perfusão cerebral, focais ou difusas, com grau de intensidade variável. Não foram observadas diferenças de perfusão cerebral entre usuários de crack e usuários de cloridrato de cocaína. As alterações tomográficas tampouco permitiram distinguir os dependentes em abstinência dos dependentes na vigência do uso. Não foi possível evidenciar associação entre o relato da quantidade diária de droga utilizada e a perfusão cerebral dos pacientes. Entretanto, foi observada correlação entre o número de meses durante os quais os pacientes consumiram droga e o grau de comprometimento da perfusão cerebral (coeficiente de correlação de Spearman: r=0,45, p

Editorial, v1, n2.

Abstract To discretize reinforced soil structures in plane strain and predict their collapse load, a simple three-node triangular finite element is formulated based on the static theorem of the limit analysis. The element satisfies the equilibrium equations and the mechanical boundary conditions in a weak sense. A modified Mohr-Coulomb yield surface is adopted to describe the reinforced soil behavior from a macromechanics point of view. It is also taken into account the possibility of tension failure of the reinforcement and failure of the reinforcement interface. The stated nonlinear convex optimization problem is cast as second-order cone programming. Numerical examples illustrate the predictive accuracy of the above scheme as well as the efficiency and speed of an interior-point method to reach optimal solutions.

Abstract Hybrid quasi-Trefftz finite elements have been applied with success to the analysis of laminated plates. Two independent fields are approximated by linearly independent, hierarchical polynomials: the stress basis in the domain, adapted from Papkovitch-Neuber solution of Navier equations, and the displacement basis, defined on element surface. The stress field that satisfies the Trefftz constraint a priori for isotropic material is adapted for orthotropic materials, which leads to the term "quasi". In this work, the hexahedral hybrid quasi-Trefftz stress element is applied to the modeling of nonsymmetric laminates and laminated composite plates with geometric discontinuities. The hierarchical p-refinement is exploited.

Abstract A large number of references dealing with the geometric stiffness matrix of the DKT finite element exist in the literature, where nearly all of them adopt an inconsistent form. While such a matrix may be part of the element to treat nonlinear problems in general, it is of crucial importance for linearized buckling analysis. The present work seems to be the first to obtain an explicit expression for this matrix in a consistent way. Numerical results on linear buckling of plates assess the element performance either with the proposed explicit consistent matrix, or with the most commonly used inconsistent matrix.

A healthy 24-year-old woman was admitted to the emergency department with acute hepatitis. She denied traveling, consumption of drugs, herbs, alcohol or medication other than the same oral contraceptive for years. The etiological work-up revealed positive Herpes Simplex Virus (HSV) 1+2 serology (IgG and IgM). Other viral serologies were negative, while Hepatitis E Virus (HEV) serology and viraemia were pending. Liver biopsy showed portal and lobular necroinflammatory activity without specific etiological findings. The remaining work-up was unremarkable. The patient developed jaundice. Acyclovir was started, considering a possible herpetic hepatitis, while waiting for HSV viraemia and immunohistochemistry in the liver biopsy, which later revealed to be negative. Despite therapy, hyperbilirubinemia and liver cytolysis worsened. At this point, HEV serology and viraemia came back positive. Ribavirin was started with rapid clinical and biochemical improvement. Liver enzymes were normal and HEV viraemia was negative after 12 weeks of ribavirin, remaining undetectable 3 months later.

Introduction: Endoscopic mucosal resection (EMR) is the treatment of choice for non-invasive colorectal flat lesions. When endoscopic piecemeal mucosal resection (EPMR) is performed, endoscopic surveillance is necessary due to the risk of recurrence. The Sydney EMR Recurrence Tool (SERT) is a 0-4 scale that classifies lesions according to size, occurrence of intraprocedural bleeding (IPB) and presence of high-grade dysplasia (HGD). Our goal is to evaluate the applicability of SERT in predicting adenoma recurrence (AR) after EPMR., Methods: This is a retrospective single-centre study with inclusion of lateral spreading lesions ≥20 mm, consecutively resected by EPMR from March 2010 to February 2018, with at least 1 endoscopic re-evaluation., Results: A total of 181 lesions were included, corresponding to 174 patients with a mean age of 68 years and male gender predominance (61%; n = 106). The most frequent location was the ascending colon (34%; n = 62). Lesions were assessed according to Paris Classification (PC): 0-IIa: 39% ( n = 71); 0-IIb: 24% ( n = 43); 0-IIa + Is: 23% ( n = 42); 0-IIa + IIb: 6% ( n = 11); 0-IIa + IIc: 2% ( n = 3). The mean size of the lesions was 33 ± 11 mm, with 25 (14%) being ≥40 mm. IPB occurred in 9 cases (5%), and 44 lesions (24%) displayed HGD. Sixty-six lesions (36.5%) were classified as SMSA (size, morphology, site, and access score) level 4. Adjunctive therapy with argon plasma coagulation (APC) was used in 37% ( n = 67) of cases. The 6-month AR rate was 16% ( n = 29). According to SERT groups, the AR rate was: SERT 0: 12% (14/120); SERT 1: 17% (6/35); SERT 2: 25% (3/12); SERT 3: 30% (3/10); SERT 4: 75% (3/4). Two of the three SERT variables (size ≥40 mm and IPB) were associated with recurrence at 6 months ( p < 0.05). HGD and the remaining tested variables (age, gender, localization, accessibility, PC, use of APC/biopsy forceps and occurrence of delayed bleeding) were not associated with AR. SERT 0 lesions showed an inferior risk of 6-month AR (adjusted OR = 2.62; p = 0.035), with a negative predictive value of 88%. SMSA correlated with SERT ( p < 0.001) and SMSA level 4 was associated with 6-month AR ( p = 0.007). Lesions classified both as SERT 0 and SMSA level <4 had the lowest 6-month recurrence rate (9.2%). The 24-month recurrence rate was 23% ( n = 41). When applying the Kaplan-Meier method, cumulative recurrence was significantly lower in SERT 0 lesions ( p = 0.006, log-rank test)., Discussion/conclusion: Resection of flat colorectal lesions by EPMR has a considerable risk of recurrence, mostly in SERT 1-4 lesions. SERT 0 lesions, especially with SMSA level <4, show a lower risk of recurrent adenoma, which might allow longer intervals to first endoscopic surveillance in the future., Competing Interests: The authors have no conflicts of interest to declare., (Copyright © 2021 by Sociedade Portuguesa de Gastrenterologia. Published by S. Karger AG, Basel.)

Competing Interests: The authors have no conflicts of interest to declare.

Competing Interests: The authors have no conflicts of interest to declare.

Background and Aims: Accurate determination of colonic polyp size is vital to an appropriate surveillance. The main aim of this study was to evaluate variation between the polyp size reported by the endoscopist and its pathological measurement., Methods: A retrospective analysis of all colonic adenomatous polyps resected in a 12-month period was performed at our center. Endoscopic and pathological size for each polyp were compared, and overestimation rates, underestimation rates, and endoscopic-pathological variation (EPV) were calculated., Results: Among the 573 polyps that were included, the mean endoscopic and pathological sizes were 8.00 and 6.66 mm, respectively. The most frequent error, in 62.1%, was overestimation by the colonoscopist. Overestimation and EPV were associated with resection technique (higher in endoscopic mucosal resection and smaller with biopsy forceps) and colonoscopist. They were not associated with years of experience in colonoscopy. Overestimation was more frequent in larger polyps., Conclusions: Our study shows significant discordance between endoscopic and pathological size of colonic polyps with a clear tendency for endoscopic overestimation. Larger polyps are more difficult to accurately assess than smaller ones. This propensity for error was not related to colonoscopist's years of experience and seems to be an individual tendency.

Background: Chronic anal fissure is a frequent and disabling disease, often affecting young adults. Botulinum toxin and lateral internal sphincterotomy are the main therapeutic options for refractory cases. Botulinum toxin is minimally invasive and safer compared with surgery, which carries a difficult post-operative recovery and fecal incontinence risk. The long-term efficacy of Botulinum toxin is not well known., Objective: The aim of this study was to evaluate the long-term efficacy and safety of Botulinum toxin in the treatment of chronic anal fissure., Methods: This was a retrospective study at a single center, including patients treated with Botulinum toxin from 2005 to 2010, followed over at least a period of 5 years. All patients were treated with injection of 25U of Botulinum toxin in the intersphincteric groove. The response was registered as complete, partial, refractory and relapse., Results: Botulinum toxin was administered to 126 patients, 69.8% ( n  = 88) were followed over a period of 5 years. After 3 months, 46.6% ( n  = 41) had complete response, 23.9% ( n  = 21) had partial response and 29.5% ( n  = 26) were refractory. Relapse was observed in 1.2% ( n  = 1) at 6 months, 11.4% ( n  = 10) at 1 year, 2.3% ( n  = 2) at 3 years; no relapse at 5 years. The overall success rate was 64.8% at 5 years of follow-up. Botulinum toxin was well tolerated by all patients and there were no complications., Conclusion: The use of Botulinum toxin to treat patients with chronic anal fissure was safe and effective in long-term follow-up.

Acute ischemia of the rectum or anal canal resulting in necrosis is extremely uncommon because both the rectum and the anal canal have excellent blood supplies. We present a case with spontaneous necrosis of the anal canal without rectal involvement. Surgical debridement was accomplished, and the recovery was uneventful. The patient was elderly, with probable atherosclerotic arterial disease, and presented with hypotension. Due to the lack of other precipitating factors, the hypoperfusion hypothesis seems to be the most suitable in this case. To the best of our knowledge, no similar cases have been reported in the literature on this subject., Competing Interests: No potential conflict of interest relevant to this article was reported.

Background and Aims: A recent review of economic studies relating to gastric cancer revealed that authors use different tests to estimate utilities in patients with and without gastric cancer. Our aim was to determine the utilities of gastric premalignant conditions and adenocarcinoma with a single standardized health measure instrument., Methods: Cross-sectional nationwide study of patients undergoing upper endoscopy (n=1,434) using the EQ-5D-5L quality of life (QoL) questionnaire., Results: According to EQ-5D-5L, utilities in individuals without gastric lesions were 0.78 (95% confidence interval: 0.76-0.80), with gastric premalignant conditions 0.79 (0.77-0.81), previously treated for gastric cancer 0.77 (0.73-0.81) and with present cancer 0.68 (0.55-0.81). Self-reported QoL according to the visual analogue scale (VAS) for the same groups were 0.67 (0.66-0.69), 0.67 (0.66-0.69), 0.62 (0.59-0.65) and 0.62 (0.54-0.70) respectively. Utilities were consistently lower in women versus men (no lesions 0.71 vs. 0.78; premalignant conditions 0.70 vs. 0.82; treated for cancer 0.72 vs. 0.78 and present cancer 0.66 vs. 0.70)., Conclusion: The health-related QoL utilities of patients with premalignant conditions are similar to those without gastric diseases whereas patients with present cancer show decreased utilities. Moreover, women had consistently lower utilities than men. These results confirm that the use of a single standardized instrument such as the EQ-5D-5L for all stages of the gastric carcinogenesis cascade is feasible and that it captures differences between conditions and gender dissimilarities, being relevant information for authors pretending to conduct further cost-utility analysis.

Introduction: Acute lower gastrointestinal bleeding (ALGIB) is a common event, which consumes considerable human and economic resources. Its incidence is expected to rise in the coming years due to an increasing aging population., Patients and Methods: Multicentric prospective analysis of patients was carried out with ALGIB in 13 Portuguese hospitals from April 2008 to May 2009, using a protocol designed by the French Association Nationale des Hépato-Gastroentérologues des Hôpitaux Généraux. Statistical analysis was carried out with SPSS 16.0., Results: In a total of 371 hemorrhagic events in 364 patients (51.4% men, mean age: 72 years), 28.4% patients showed hemodynamic instability and 54.2% were under single/combined medication with antiaggregants/NSAIDs/heparin/anticoagulants; blood transfusion was administered in 34.8% of patients. Sigmoidoscopy was the first endoscopic procedure performed in 61.3% of patients and rectal enema was the first method of bowel preparation in 67.3% of them. Endoscopic hemostasis was performed in 22.2% of all cases with efficacy ranging from 84.6 to 96.2%. Most frequent diagnoses were ischemic colitis (23.7%), diverticulosis (20.8%), and colorectal malignancies (12.4%). Surgery was needed in 8% of patients, and global mortality rate was 2.2%. Risk factors for poor outcome on multivariate analysis were heparin use before bleeding (hazards ratio: 10.6; 95% confidence interval: 0.94-119.48) and in-hospital bleeding (hazards ratio: 5.6; 95% confidence interval: 1.01-19.70)., Conclusion: ALGIB seems to occur frequently in Portugal with a low mortality rate. Previous heparin use and in-hospital bleeding are associated with worse prognosis. Our management relies on early endoscopic examinations, which are highly available, safe, and accurate. A successful endoscopic therapeutic approach was possible in one fifth of the patients.