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1.
Int J Biol Macromol ; 275(Pt 1): 133588, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38960246

RESUMEN

The understanding of cancer immunity and antitumor factors generated by natural polysaccharides is not yet fully comprehended. Polysaccharides, like cashew gum (CG), can exhibit immunomodulatory action and may assist in the antitumor process and side effects relieve. This study aimed to determine the antitumor effect of CG alone or in combination with cyclophosphamide (CTX), and its interactions with immune cells, in a murine melanoma model, using the B16-F10 cell line. Tumor growth inhibition, hematological, histopathological, ELISA, flow cytometry, immunofluorescence, and qRT-PCR analyses were performed to elucidate the antitumor potential, involvement of immune cells, and potential toxic effects. CG showed significant tumor growth inhibition, reaching up to 42.9 % alone and 51.4 % in combination with CTX, with mild toxicity to organs. CG enhanced leukocyte count, even in the presence of CTX. Furthermore, CG influenced the activation of tumor-associated macrophages (TAM), characterized by an increase in Il4, as well as a reduction in Ifng, Il1b, Tgfb, and Il6 gene expression. Nevertheless, these effects did not compromise the antitumor activity of CG. In summary, the combination of CG with CTX is a promising approach for leukopenia, one of the most important side effects of cancer treatment and deserves further investigation.

2.
BMC Med Educ ; 21(1): 248, 2021 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-33926437

RESUMEN

BACKGROUND: With the emergence of the new coronavirus pandemic (COVID-19), distance learning, especially that mediated by information and digital communication technologies, has been adopted in all areas of knowledge and at all levels, including medical education. Imminently practical areas, such as pathology, have made traditional teaching based on conventional microscopy more flexible through the synergies of computational tools and image digitization, not only to improve teaching-learning but also to offer alternatives to repetitive and exhaustive histopathological analyzes. In this context, machine learning algorithms capable of recognizing histological patterns in kidney biopsy slides have been developed and validated with a view to building computational models capable of accurately identifying renal pathologies. In practice, the use of such algorithms can contribute to the universalization of teaching, allowing quality training even in regions where there is a lack of good nephropathologists. The purpose of this work is to describe and test the functionality of SmartPathk, a tool to support teaching of glomerulopathies using machine learning. The training for knowledge acquisition was performed automatically by machine learning methods using the J48 algorithm to create a computational model of an appropriate decision tree. RESULTS: An intelligent system, SmartPathk, was developed as a complementary remote tool in the teaching-learning process for pathology teachers and their students (undergraduate and graduate students), showing 89,47% accuracy using machine learning algorithms based on decision trees. CONCLUSION: This artificial intelligence system can assist in teaching renal pathology to increase the training capacity of new medical professionals in this area.


Asunto(s)
COVID-19 , Educación a Distancia , Inteligencia Artificial , Humanos , Aprendizaje Automático , SARS-CoV-2 , Enseñanza
3.
Artif Intell Med ; 103: 101808, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-32143802

RESUMEN

Glomeruli are histological structures of the kidney cortex formed by interwoven blood capillaries, and are responsible for blood filtration. Glomerular lesions impair kidney filtration capability, leading to protein loss and metabolic waste retention. An example of lesion is the glomerular hypercellularity, which is characterized by an increase in the number of cell nuclei in different areas of the glomeruli. Glomerular hypercellularity is a frequent lesion present in different kidney diseases. Automatic detection of glomerular hypercellularity would accelerate the screening of scanned histological slides for the lesion, enhancing clinical diagnosis. Having this in mind, we propose a new approach for classification of hypercellularity in human kidney images. Our proposed method introduces a novel architecture of a convolutional neural network (CNN) along with a support vector machine, achieving near perfect average results on FIOCRUZ data set in a binary classification (lesion or normal). Additionally, classification of hypercellularity sub-lesions was also evaluated, considering mesangial, endocapilar and both lesions, reaching an average accuracy of 82%. Either in binary task or in the multi-classification one, our proposed method outperformed Xception, ResNet50 and InceptionV3 networks, as well as a traditional handcrafted-based method. To the best of our knowledge, this is the first study on deep learning over a data set of glomerular hypercellularity images of human kidney.


Asunto(s)
Enfermedades Renales/patología , Glomérulos Renales/patología , Redes Neurales de la Computación , Máquina de Vectores de Soporte , Humanos , Enfermedades Renales/clasificación , Enfermedades Renales/diagnóstico por imagen , Glomérulos Renales/diagnóstico por imagen
4.
J. bras. patol. med. lab ; 49(4): 273-277, Aug. 2013. ilus, tab
Artículo en Inglés | LILACS | ID: lil-697102

RESUMEN

INTRODUCTION: Endoscopic submucosal dissection (ESD) of early neoplasias of the gastrointestinal tract (GIT) has been increasingly applied as an alternative to invasive surgical procedures, with the aim to preserve the patient's organ and quality of life, although it does not allow the histopathological analysis of lymph nodes. Previous studies demonstrated that the presence of neoplastic emboli in lymphatic (lymphatic vascular invasion [LVI]) or blood vessels (blood vascular invasion [BVI]) is considered a positive predictive factor for the occurrence of lymph node metastasis. The assessment of vascular invasion carried out only by routine hematoxylin and eosin staining (HE) may yield both falsepositive and false-negative results. D2-40 is a specific monoclonal antibody to the lymphatic endothelium. Thus, it is useful for identifying LVI and distinguishing if tumor embolization is found in blood or lymphatic vessels. OBJECTIVE: To determine the role of immunohistochemistry (IHC) in the assessment of ESD specimens by comparing the detection of LVI and BVI by HE and IHC with D2-40 and CD34 immunolabeling. METHOD: We conducted the IHC study using D2-40 and CD34 markers (pan-endothelial) in 30 cases of ESD with histological diagnosis of carcinoma in order to assess the presence of LVI and BVI. RESULTS: The detection of LVI was more prevalent than BVI. Three out of six cases with LVI were false-positive by HE and six were false-negative by IHC. Regarding BVI, five cases were identified and one was false-negative by IHC. CONCLUSION: Our results indicated that the histopathological analysis of ESD specimens by exclusively routine HE staining does not allow proper evaluation of BVI or LVI.


INTRODUÇÃO: A dissecção endoscópica da submucosa (DES) de neoplasias precoces do trato gastrointestinal (TGI) tem sido cada vez mais aplicada como alternativa aos procedimentos cirúrgicos invasivos, visando a preservar o órgão e a qualidade de vida do paciente, contudo, não possibilita a avaliação histopatológica de linfonodos. Estudos anteriores demonstraram que a presença de êmbolos neoplásicos, em vasos linfáticos (invasão vascular linfática [IVL]) ou sanguíneos (invasão vascular sanguínea [IVS]), é considerada um fator preditivo positivo para ocorrência de metástase linfonodal. A avaliação da invasão vascular realizada apenas pela coloração de rotina hematoxilina e eosina (HE) pode gerar resultados falso-positivos e falso-negativos. O D2-40 é um anticorpo monoclonal específico para endotélio linfático, sendo, portanto, útil para identificar IVL e distinguir se a embolização tumoral encontra-se em vasos sanguíneos ou linfáticos. OBJETIVO: Determinar o papel do estudo imuno-histoquímico (IHQ) na avaliação de espécimes de DES, comparando a detecção de IVL e IVS, pelo HE e IHQ com marcação por D2-40 e CD34. MÉTODO: Foi realizado estudo IHQ utilizando os marcadores D2-40 e CD34 (pan-endotelial) em 30 casos de produtos de DES com diagnóstico histológico de carcinoma para avaliar a presença de IVL e IVS. RESULTADOS: A detecção de IVL foi maior que a de IVS. Dos seis casos com IVL ao HE, três eram falso-positivos e seis, falso-negativos à IHQ. Em relação à IVS, foram identificados cinco casos falsopositivos e um falso-negativo à IHQ. CONCLUSÃO: Nossos resultados indicaram que a análise histopatológica dos produtos de DES realizando apenas a coloração HE não permite a avaliação adequada da presença de IVS ou IVL.

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