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1.
Arq. neuropsiquiatr ; 81(12): 1134-1145, Dec. 2023. tab, graf
Article in English | LILACS-Express | LILACS | ID: biblio-1527905

ABSTRACT

Abstract In recent decades, there have been significant advances in the diagnosis of diffuse gliomas, driven by the integration of novel technologies. These advancements have deepened our understanding of tumor oncogenesis, enabling a more refined stratification of the biological behavior of these neoplasms. This progress culminated in the fifth edition of the WHO classification of central nervous system (CNS) tumors in 2021. This comprehensive review article aims to elucidate these advances within a multidisciplinary framework, contextualized within the backdrop of the new classification. This article will explore morphologic pathology and molecular/genetics techniques (immunohistochemistry, genetic sequencing, and methylation profiling), which are pivotal in diagnosis, besides the correlation of structural neuroimaging radiophenotypes to pathology and genetics. It briefly reviews the usefulness of tractography and functional neuroimaging in surgical planning. Additionally, the article addresses the value of other functional imaging techniques such as perfusion MRI, spectroscopy, and nuclear medicine in distinguishing tumor progression from treatment-related changes. Furthermore, it discusses the advantages of evolving diagnostic techniques in classifying these tumors, as well as their limitations in terms of availability and utilization. Moreover, the expanding domains of data processing, artificial intelligence, radiomics, and radiogenomics hold great promise and may soon exert a substantial influence on glioma diagnosis. These innovative technologies have the potential to revolutionize our approach to these tumors. Ultimately, this review underscores the fundamental importance of multidisciplinary collaboration in employing recent diagnostic advancements, thereby hoping to translate them into improved quality of life and extended survival for glioma patients.


Resumo Nas últimas décadas, houve avanços significativos no diagnóstico de gliomas difusos, impulsionados pela integração de novas tecnologias. Esses avanços aprofundaram nossa compreensão da oncogênese tumoral, permitindo uma estratificação mais refinada do comportamento biológico dessas neoplasias. Esse progresso culminou na quinta edição da classificação da OMS de tumores do sistema nervoso central (SNC) em 2021. Esta revisão abrangente tem como objetivo elucidar esses avanços de forma multidisciplinar, no contexto da nova classificação. Este artigo irá explorar a patologia morfológica e as técnicas moleculares/genéticas (imuno-histoquímica, sequenciamento genético e perfil de metilação), que são fundamentais no diagnóstico, além da correlação dos radiofenótipos da neuroimagem estrutural com a patologia e a genética. Aborda sucintamente a utilidade da tractografia e da neuroimagem funcional no planejamento cirúrgico. Destacaremos o valor de outras técnicas de imagem funcional, como ressonância magnética de perfusão, espectroscopia e medicina nuclear, na distinção entre a progressão do tumor e as alterações relacionadas ao tratamento. Discutiremos as vantagens das diferentes técnicas de diagnóstico na classificação desses tumores, bem como suas limitações em termos de disponibilidade e utilização. Além disso, os crescentes avanços no processamento de dados, inteligência artificial, radiômica e radiogenômica têm grande potencial e podem em breve exercer uma influência substancial no diagnóstico de gliomas. Essas tecnologias inovadoras têm o potencial de revolucionar nossa abordagem a esses tumores. Em última análise, esta revisão destaca a importância fundamental da colaboração multidisciplinar na utilização dos recentes avanços diagnósticos, com a esperança de traduzi-los em uma melhor qualidade de vida e uma maior sobrevida.

2.
CienciaUAT ; 17(2): 181-196, ene.-jun. 2023. tab, graf
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1447828

ABSTRACT

RESUMEN La evapotranspiración de referencia (ETo) es una variable hidrológica de gran importancia en el manejo del riego. Su estimación se realiza con la ecuación de Penman-Montieth (PM), que requiere de muchas variables meteorológicas, las cuales, a veces, no se encuentran disponibles. Dado que la ETo es una variable no lineal y compleja, en los últimos años han surgido métodos alternativos para su estimación, como las redes neuronales artificiales (RNA). El objetivo del presente trabajo fue estimar la evapotranspiración de referencia (ETo) usando la ecuación de Penman-Montieth, a fin de desarrollar modelos de redes neuronales artificiales (RNA) que permitan predecir la ETo en regiones con información climatológica limitada, y su vez comparar el desempeño de tres modelos de RNA: FFNN, ERNN y NARX. Se utilizó información diaria durante el periodo 1 de enero de 2007 al 31 de diciembre de 2018, de las estaciones meteorológicas ENP8 y ENP4 de la CDMX. Se realizó un análisis de correlación y el análisis de sensibilidad de Garson para estudiar 2 casos (red estática FFNN y redes dinámicas: ERNN y NARX) usando 3 modelos de RNA: 1) RNA con 6 entradas: radiación solar (Rad), temperatura máxima y mínima (Tmax, Tmin), humedad relativa máxima y mínima (HRmax, HRmin) y velocidad del viento (u); y 2) RNA con 2 entradas (Rad y Tmax). La variable de salida fue la ETo calculada con la ecuación de PM. En todos los casos, las 3 RNA fueron muy parecidas, la diferencia más notable es que las redes dinámicas (ERNN y NARX) requieren de menor número de iteraciones para llegar al desempeño óptimo. Las RNA entrenadas, únicamente con Rad y Tmax como entradas, fueron capaces de predecir la ETo en el largo plazo, durante 440 d, en otra estación meteorológica cercana (ENP4), con eficiencias mayores al 90 %.


ABSTRACT Reference evapotranspiration (ETo) is a hydrological variable of great importance in irrigation management. Its estimation is carried out with the Penman-Montieth (PM) equation that requires many meteorological variables and that are sometimes not available. Since ETo is a nonlinear and complex variable, in recent years alternative methods have emerged for its estimation, such as artificial neural networks (ANN). The objective of this work was to estimate the reference evapotranspiration (ETo) using the Penman-Montieth equation, in order to develop artificial neural network (ANN) models that allow ETo to be predicted in regions with limited climatological information, and in turn to compare the performance of three RNA models: FFNN, ERNN and NARX. Daily informtion was used during the January 1, 2007 to December 31, 2018 period, for the ENP8 and ENP4 meteorological stations in Mexico city. Based on the correlation analysis and the Garson sensitivity analysis, 2 cases were studied for the 3 ANN models: 1) ANN with 6 inputs: solar radiation (Rad), maximum and minimum temperature (Tmax, Tmin), maximum and minimum relative humidity (RHmax, RHmin), and wind speed (u), and 2) RNA with 2 inputs (Rad and Tmax). The output variable was the ETo, calculated with the PM equation. In all cases, the performance of the 3 ANNs was very similar. The most notable difference is that the dynamic networks (ERNN and NARX) require fewer iterations to achieve the optimum performance. ANNs trained only with radiation and maximum temperature as inputs were able to predict a long-term ETo for 440 at another nearby meteorological station (ENP4), with efficiencies greater than 90 %.

3.
Radiol. bras ; 56(1): 42-49, Jan.-Feb. 2023. tab, graf
Article in Portuguese | LILACS-Express | LILACS | ID: biblio-1422525

ABSTRACT

Resumo O adenocarcinoma ductal de pâncreas é uma das neoplasias malignas mais agressivas, com taxas de sobrevivência anuais inferiores a 20%. Os métodos axiais (tomografia computadorizada e ressonância magnética) têm papel fundamental no diagnóstico e estadiamento da doença, por fornecerem adequada resolução anatômica na avaliação de estruturas-chave, principalmente vasculares. O adenocarcinoma ductal de pâncreas é frequentemente descoberto em estágios avançados e sem viabilidade de ressecção cirúrgica, e nesse cenário o desenvolvimento de alternativas terapêuticas minimamente invasivas tem sido ainda mais importante para a mudança de sua história natural. A eletroporação irreversível, procedimento intervencionista que minimiza efeitos deletérios nos tecidos adjacentes, vem se destacando no tratamento de lesões tradicionalmente consideradas irressecáveis. Essa técnica, apesar de ganhar cada vez mais espaço no manejo terapêutico do adenocarcinoma ductal de pâncreas, ainda é pouco familiar aos radiologistas. Neste estudo, buscamos expor, de forma sucinta e didática, os fundamentos da técnica, as principais características de imagem e os critérios de elegibilidade que devem ser considerados para indicação da eletroporação irreversível nessa doença.


Abstract Pancreatic ductal adenocarcinoma is one of the most aggressive malignant neoplasms, with a one-year survival rate below 20%. Axial methods (computed tomography and magnetic resonance imaging) play a fundamental role in the diagnosis and staging of the disease, because they provide adequate anatomical resolution in the assessment of key structures, mainly vascular structures. Pancreatic ductal adenocarcinoma is most often discovered in advanced stages, when surgical resection is no longer feasible. In that scenario, minimally invasive treatment alternatives have been developed in attempts to change the natural history of the disease. Irreversible electroporation, an interventional procedure that minimizes deleterious effects on adjacent tissues, has proven useful for the treatment of tumors traditionally considered unresectable. Despite the growing acknowledgment of this technique as a tool for the management of pancreatic ductal adenocarcinoma, it is still relatively unknown among radiologists. In this study, we sought to provide an overview of the main characteristics and eligibility criteria that must be considered for the indication of irreversible electroporation in cases of pancreatic ductal adenocarcinoma.

4.
Int. braz. j. urol ; 44(3): 642-644, May-June 2018. graf
Article in English | LILACS | ID: biblio-954048

ABSTRACT

ABSTRACT Renal replacement lipomatosis is a condition characterized by varying degrees of renal parenchymal atrophy and perirenal fibrofatty proliferation secondary to chronic inflammation such as xanthogranulomatous pyelonephritis. In severe cases, imaging findings can be misdiagnosed as retroperitoneal liposarcoma.


Subject(s)
Humans , Male , Retroperitoneal Neoplasms/diagnostic imaging , Pyelonephritis, Xanthogranulomatous/diagnosis , Kidney Diseases/diagnostic imaging , Lipomatosis/diagnostic imaging , Liposarcoma/diagnostic imaging , Retroperitoneal Neoplasms/pathology , Pyelonephritis, Xanthogranulomatous/pathology , Radiography, Abdominal , Tomography, X-Ray Computed , Diagnosis, Differential , Kidney Diseases/pathology , Lipomatosis/pathology , Liposarcoma/pathology , Middle Aged
5.
Bol. latinoam. Caribe plantas med. aromát ; 13(6): 527-536, nov.2014. ilus, tab
Article in English | LILACS | ID: lil-795823

ABSTRACT

The chemical constituents of the hexane and methanol extracts obtained from the branch bark of Bursera simaruba (Burseraceae) grown in Querétaro, Mexico, were investigated by GC-MS, HPLC coupled to DAD, and NMR techniques. Seventeen compounds, including terpenoids, flavonoids, phenolic acids, long-chain fatty acids (FA), methyl esters of FA and sucrose, were identified. In addition, an assessment of the antiradical activity of the methanol extract (ME) was also carried out using DPPH, ABTS, FRAP and DPV assays. The DPPH, ABTS and FRAP assays showed a low antioxidant capacity for the ME. This was in accordance with the relatively low quantities of phenols found in the extract. However, according to the differential pulse voltammetry assay (DVP), this extract exhibited an oxidation potential close to those of quercetin and (+)-catechin, two of the flavonoids with recognized good antioxidant power. This indicated that the ME does contain compounds with good antioxidant capacity and suggested that sometimes the most popular methods commonly used might be underestimating the true antioxidant capacities of plant samples and how the DPV is a valuable complementary tool to be taken into consideration when conducting these in vitro assays...


Los constituyentes químicos de los extractos hexánicos y metanólicos de la corteza de ramas de Bursera simaruba (Burseraceae) recolectada en Querétaro, México, fueron investigados mediante las Cromatografías de Gases acoplada a Espectrometría de masas (GC-MS) y de líquidos de alta resolución (HPLC) acoplada a un detector de arreglo de diodos (DAD) (HPLC-DAD) y mediante RMN. Diecisiete compuestos, incluyendo terpenos, flavonoides, ácidos fenólicos, ácidos grasos de cadena larga (AG), ésteres metílicos de AG y la sacarosa fueron identificados. De manera adicional, se determinó la actividad antioxidante del extracto metanólico utilizando los ensayos de DPPH, ABTS, FRAP y DPV (Voltametría de Pulso Diferencial). Los métodos de DPPH, ABTS y FRAP indicaron una baja capacidad antioxidante para este extracto. Esta observación estuvo de acuerdo con las bajas cantidades de fenólicos encontrados en este extracto. Sin embargo, mediante el método DPV, el extracto tuvo un potencial de oxidación cercano a los de la quercetina y la (+)-catequina, dos de los flavonoides con reconocida buna capacidad antioxidante. Estos resultados indican que el extracto sí contiene metabolitos secundarios con buena capacidad antioxidante y sugieren además que los métodos más comunes pueden subestimar la verdadera capacidad antioxidante de extractos de plantas y resalta la importancia del método DPV como complementario a tener en cuenta en estos tipos de estudios in vitro...


Subject(s)
Humans , Antioxidants/pharmacology , Bursera/chemistry , Plant Extracts/pharmacology , Plant Extracts/chemistry , Antioxidants/chemistry , Chromatography, High Pressure Liquid , Electrochemical Techniques , Phenols/analysis , Gas Chromatography-Mass Spectrometry , Terpenes/analysis
6.
Rev. méd. Chile ; 138(10): 1272-1275, oct. 2010. tab
Article in Spanish | LILACS | ID: lil-572939

ABSTRACT

Background: Tuberculous spondylodiscitis is relatively uncommon but represents the most common location of osseous tuberculosis. Aim: To describe clinical features, imaging studies and laboratory tests to establish the diagnosis in a group of patients living in Cádiz (Spain). Material and Methods: Retrospective analysis of medical records of patients with tuberculous spondylodiscitis diagnosed between 2000 and 2009. The diagnosis was based on microorganism recovery from vertebral samples obtained by imaging guided biopsies. Results: Six patients with positive Mycobac-terium tuberculosis cultures from vertebral samples, were identified (10 percent of extra-pulmonary tuberculosis). In only 2 patients the Ziehl-Nielsen stain was positive, and histology was compatible in 4 cases. Four patients were females, their mean age was 54.3 years and the mean duration of symptoms was 7.3 months. Three patients had lumbar location and a positive Mantoux test. A soft tissue abscess was present in 4 cases. None of these patients had neurological complications. The treatment with four tuberculostatic agents (isoniazid, rifampicin, pyrazinamide and ethambutol) was effective in 5 patients. Conclusions: Tuberculous spondylodiscitis may become a serious disease due to diagnostic and treatment delays. The main examinations to establish diagnosis are magnetic resonance imaging and biopsy with microbiological culture. Generally, antituberculous therapy is effective in this clinical situation.


Subject(s)
Adult , Aged , Aged, 80 and over , Female , Humans , Male , Discitis/diagnosis , Tuberculosis, Spinal/diagnosis , Antitubercular Agents/therapeutic use , Discitis/drug therapy , Retrospective Studies , Spain , Tuberculosis, Spinal/drug therapy
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