Refactoring and performance analysis of the main CNN architectures: using false negative rate minimization to solve the clinical images melanoma detection problem.

BACKGROUND: Melanoma is one of the deadliest tumors in the world. Early detection is critical for first-line therapy in this tumor pathology and it remains challenging due to the need for histological analysis to ensure correctness in diagnosis. Therefore, multiple computer-aided diagnosis (CAD) systems working on melanoma images were proposed to mitigate the need of a biopsy. However, although the high global accuracy is declared in literature results, the CAD systems for the health fields must focus on the lowest false negative rate (FNR) possible to qualify as a diagnosis support system. The final goal must be to avoid classification type 2 errors to prevent life-threatening situations. Another goal could be to create an easy-to-use system for both physicians and patients. RESULTS: To achieve the minimization of type 2 error, we performed a wide exploratory analysis of the principal convolutional neural network (CNN) architectures published for the multiple image classification problem; we adapted these networks to the melanoma clinical image binary classification problem (MCIBCP). We collected and analyzed performance data to identify the best CNN architecture, in terms of FNR, usable for solving the MCIBCP problem. Then, to provide a starting point for an easy-to-use CAD system, we used a clinical image dataset (MED-NODE) because clinical images are easier to access: they can be taken by a smartphone or other hand-size devices. Despite the lower resolution than dermoscopic images, the results in the literature would suggest that it would be possible to achieve high classification performance by using clinical images. In this work, we used MED-NODE, which consists of 170 clinical images (70 images of melanoma and 100 images of naevi). We optimized the following CNNs for the MCIBCP problem: Alexnet, DenseNet, GoogleNet Inception V3, GoogleNet, MobileNet, ShuffleNet, SqueezeNet, and VGG16. CONCLUSIONS: The results suggest that a CNN built on the VGG or AlexNet structure can ensure the lowest FNR (0.07) and (0.13), respectively. In both cases, discrete global performance is ensured: 73% (accuracy), 82% (sensitivity) and 59% (specificity) for VGG; 89% (accuracy), 87% (sensitivity) and 90% (specificity) for AlexNet.

Experiencia formadora con cuatro guías de buenas prácticas clínicas de la registered nurses' association of ontario

El presente artículo trata sobre la implementación de cuatro guías elaboradas por la Registered Nurses' Association of Ontario (Canadá) en la enseñanza de pregrado de la Carrera de Enfermería de la Universidad de Chile, proceso que se enmarca en el primer convenio establecido entre la Universidad de Chile y esta asociación. El acuerdo instaurado entre ambas instituciones promovió la incorporación de las guías: Valoración y Selección de Accesos Vasculares, Atención a las Familias, Establecimiento de Relación Terapéutica, y Valoración y Manejo del Dolor, al plan de formación de la Carrera de Enfermería, proceso liderado por docentes asesores de cada una de las guías a través de diversas estrategias pedagógicas y didácticas, demostrando un aporte significativo de este material al aprendizaje de los estudiantes de enfermería de la institución académica.

This article describes the implementation of four guidelines developed by the Registered Nurses' Association of Ontario for undergraduate nursing education at the Universidad de Chile, a process that is part of the first agreement reached between the University of Chile and the Registered Nurses' Association of Ontario. The agreement established between both institutions helped incorporate the following guidelines: Assessment and Selection of Vascular Accesses, Family Care, Establishment of Therapeutic Relationship, and Assessment and Management of Pain, into the training plan of the nursing program, a process led by the faculty advisors of each of the guidelines through various pedagogical and didactic strategies, demonstrating a significant contribution of this material to the learning process of the nursing students.

Este artigo trata da implementação de quatro guias desenvolvidas pela Associação de Enfermeiros Registrados de Ontário (Canadá) para a educação de enfermagem de graduação na Universidade do Chile, um processo que faz parte do primeiro acordo estabelecido entre Universidade do Chile e a Associação de Enfermeiros Registrados de Ontário. O acordo assinado entre as duas instituições promoveu a incorporação das seguintes guias: Avaliação e Seleção de Acessos Vasculares, Cuidado Familiar, Estabelecimento de Relacionamento Terapêutico e Avaliação e Gerenciamento da Dor, ao plano de treinamento do programa de enfermagem, um processo conduzido pelos orientadores de cada uma das guias através de várias estratégias pedagógicas e didáticas, demonstrando uma contribuição significativa deste material para o aprendizado dos estudantes de enfermagem.

Hypertensive Nephropathy: Unveiling the Possible Involvement of Hemichannels and Pannexons.

Hypertension is one of the most common risk factors for developing chronic cardiovascular diseases, including hypertensive nephropathy. Within the glomerulus, hypertension causes damage and activation of mesangial cells (MCs), eliciting the production of large amounts of vasoactive and proinflammatory agents. Accordingly, the activation of AT1 receptors by the vasoactive molecule angiotensin II (AngII) contributes to the pathogenesis of renal damage, which is mediated mostly by the dysfunction of intracellular Ca2+ ([Ca2+]i) signaling. Similarly, inflammation entails complex processes, where [Ca2+]i also play crucial roles. Deregulation of this second messenger increases cell damage and promotes fibrosis, reduces renal blood flow, and impairs the glomerular filtration barrier. In vertebrates, [Ca2+]i signaling depends, in part, on the activity of two families of large-pore channels: hemichannels and pannexons. Interestingly, the opening of these channels depends on [Ca2+]i signaling. In this review, we propose that the opening of channels formed by connexins and/or pannexins mediated by AngII induces the ATP release to the extracellular media, with the subsequent activation of purinergic receptors. This process could elicit Ca2+ overload and constitute a feed-forward mechanism, leading to kidney damage.