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1.
Emerg Radiol ; 31(1): 1-6, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37994976

RESUMO

PURPOSE: Basilar artery strokes are rare but can have characteristic imaging findings that can often be overlooked. This retrospective study aims to assess radiology residents' ability to identify CT imaging findings of basilar artery occlusion in a simulated call environment. METHODS: The Wisdom in Diagnostic Imaging Emergent/Critical Care Radiology Simulation (WIDI SIM)-a tested and reliable computer-aided emergency imaging simulation-was employed to assess resident readiness for independent radiology call. The simulations include 65 cases of varying complexity, including normal studies, with one case specifically assessing basilar artery stroke. Residents were presented with a single, unique case of basilar artery occlusion in two separate years of testing and were only provided with non-contrast CT images. Residents' free text responses were manually scored by faculty members using a standardized grading rubric, with errors subsequently classified by type. RESULTS: A total of 454 radiology residents were tested in two separate years on the imaging findings of basilar artery occlusion using the Wisdom in Diagnostic Imaging simulation web-based testing platform. Basilar artery occlusion was consistently underdiagnosed by radiology residents being tested for call readiness irrespective of the numbers of years in training. On average, only 14% of radiology residents were able to correctly identify basilar artery occlusion on non-contrast CT. CONCLUSIONS: Our findings underscore a potential gap in radiology residency training related to the detection of basilar artery occlusion, highlighting the potential need for increased educational efforts in this area.


Assuntos
Internato e Residência , Radiologia , Acidente Vascular Cerebral , Humanos , Artéria Basilar/diagnóstico por imagem , Competência Profissional , Radiologia/educação , Estudos Retrospectivos
2.
Emerg Radiol ; 31(5): 653-660, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38969914

RESUMO

INTRODUCTION: The calcaneus is the most commonly fractured tarsal bone. Diagnosis is often challenging due to subtle radiographic changes and requires timely identification to prevent complications, including subtalar arthritis, neurovascular injury, malunion, osteomyelitis, and compartment syndrome. Treatment varies based on fracture type, with non-surgical methods for non-displaced stress fractures and surgical interventions for displaced or intra-articular fractures. METHODS: This study utilized the Wisdom in Diagnostic Imaging Simulation (WIDI SIM) platform, an emergency imaging simulation designed to assess radiology resident preparedness for independent call. During an 8-hour simulation, residents were tested on 65 cases across various imaging modalities of varying complexity, including normal studies. A single, unique case of calcaneal fracture was included within the simulation in four separate years of testing. Cases were assessed using a standardized grading rubric by subspecialty radiology faculty, with errors subsequently classified by type. RESULTS: A total of 1279 residents were tested in five separate years on the findings of calcaneal fractures of 5 different patients. Analysis revealed a consistent pattern of missed diagnoses across all training years, primarily attributed to observational errors. There was limited improvement with training progression as all training years exhibited similar average performance levels. CONCLUSIONS: Calcaneal fractures pose a diagnostic challenge due to their frequent subtle radiographic findings, especially in stress fractures. Simulation-based evaluations using WIDI SIM highlighted challenges in radiology residents' proficiency in diagnosing calcaneal fractures. Addressing these challenges through targeted education and exposure to diverse cases is essential to improve diagnostic accuracy and reduce complications with calcaneal fractures.


Assuntos
Calcâneo , Fraturas Ósseas , Humanos , Calcâneo/lesões , Calcâneo/diagnóstico por imagem , Fraturas Ósseas/diagnóstico por imagem , Internato e Residência , Masculino , Competência Clínica , Radiologia/educação , Treinamento por Simulação , Feminino , Adulto
3.
Emerg Radiol ; 31(2): 187-192, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38340256

RESUMO

BACKGROUND AND PURPOSE: Suppurative retropharyngeal lymphadenitis is a retropharyngeal space infection almost exclusively seen in the young (4-8 years old) pediatric population. It can be misdiagnosed as a retropharyngeal abscess, leading to unnecessary invasive treatment procedures. This retrospective study aims to assess radiology residents' ability to independently identify CT imaging findings and make a definitive diagnosis of suppurative retropharyngeal lymphadenitis in a simulated call environment. MATERIALS AND METHODS: The Wisdom in Diagnostic Imaging Emergent/Critical Care Radiology Simulation (WIDI SIM) is a computer-aided emergency imaging simulation proven to be a reliable method for assessing resident preparedness for independent radiology call. The simulation included 65 cases across various imaging modalities of varying complexity, including normal studies, with one case specifically targeting suppurative retropharyngeal adenitis identification. Residents' free text responses were manually scored by faculty members using a standardized grading rubric, with errors subsequently classified by type. RESULTS: A total of 543 radiology residents were tested in three separate years on the imaging findings of suppurative retropharyngeal lymphadenitis using the Wisdom in Diagnostic Imaging simulation web-based testing platform. Suppurative retropharyngeal lymphadenitis was consistently underdiagnosed by radiology residents being tested for call readiness irrespective of the numbers of years in training. On average, only 3.5% of radiology residents were able to correctly identify suppurative retropharyngeal lymphadenitis on a contrast-enhanced computed tomography (CT). CONCLUSIONS: Our findings underscore a potential gap in radiology residency training related to the accurate identification of suppurative retropharyngeal lymphadenitis, highlighting the potential need for enhanced educational efforts in this area.


Assuntos
Internato e Residência , Linfadenite , Radiologia , Humanos , Criança , Pré-Escolar , Estudos Retrospectivos , Radiologia/educação , Competência Profissional , Linfadenite/diagnóstico por imagem
4.
Hepatology ; 72(1): 140-154, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-31553806

RESUMO

BACKGROUND AND AIMS: Advances in cancer treatment have improved survival; however, local recurrence and metastatic disease-the principal causes of cancer mortality-have limited the ability to achieve durable remissions. Local recurrences arise from latent tumor cells that survive therapy and are often not detectable by conventional clinical imaging techniques. Local recurrence after transarterial embolization (TAE) of hepatocellular carcinoma (HCC) provides a compelling clinical correlate of this phenomenon. In response to TAE-induced ischemia, HCC cells adapt their growth program to effect a latent phenotype that precedes local recurrence. APPROACH AND RESULTS: In this study, we characterized and leveraged the metabolic reprogramming demonstrated by latent HCC cells in response to TAE-induced ischemia to enable their detection in vivo using dynamic nuclear polarization (DNP) magnetic resonance spectroscopic imaging (MRSI) of 13 carbon-labeled substrates. Under TAE-induced ischemia, latent HCC cells demonstrated reduced metabolism and developed a dependence on glycolytic flux to lactate. Despite the hypometabolic state of these cells, DNP-MRSI of 1-13 C-pyruvate and its downstream metabolites, 1-13 C-lactate and 1-13 C-alanine, predicted histological viability. CONCLUSIONS: These studies provide a paradigm for imaging latent, treatment-refractory cancer cells, suggesting that DNP-MRSI provides a technology for this application.


Assuntos
Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/terapia , Embolização Terapêutica , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/terapia , Imageamento por Ressonância Magnética/métodos , Espectroscopia de Ressonância Magnética , Animais , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Modelos Animais de Doenças , Humanos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Masculino , Ratos , Ratos Wistar
5.
Pediatr Radiol ; 51(5): 773-781, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33442781

RESUMO

BACKGROUND: A resident working under the entrustable professional activity of a graduated independent coverage model must identify nonaccidental trauma and notify clinicians of this concern to facilitate potential removal of the child from harm. The resident's role in identifying child abuse has not previously been studied. OBJECTIVE: The purpose of this study was to assess radiology residents' ability to identify radiographic imaging findings of nonaccidental trauma in a simulated call environment. MATERIALS AND METHODS: The Wisdom in Diagnostic Imaging Emergent/Critical Care Radiology Simulation (WIDI SIM) is a strategically designed computer-aided simulation of an emergency imaging experience that has been rigorously tested and proven to be a reliable means for assessing resident preparedness to competently and independently cover radiology call. The residents are provided with 65 cases of varying difficulty, including normal studies. Those cases include ones that require the resident to accurately identify skeletal findings of nonaccidental trauma. The residents respond using free text that is then scored manually by faculty members utilizing a robust grading rubric. Missed cases are then categorized by observation error and/or interpretative errors. RESULTS: A total of 675 radiology residents were given a case of nonaccidental trauma using the WIDI simulation web-based test platform between 2014 and 2017. Child abuse was consistently underdiagnosed by radiology residents being tested for call readiness irrespective of the numbers of years in training. Correct diagnostic score averages per year ranged from 10% to 79%. In year 1, 71% of residents correctly diagnosed nonaccidental trauma with a total of 101 participants. In year 2, 130 residents participated with only 20% answering correctly. In year 3, there were 201 participants with 79% correctly diagnosing nonaccidental trauma. In year 4, only 10% of 243 residents accurately diagnosed nonaccidental trauma. Residents from various stages of training were tested. Cases used with leading histories provided, accounted for a higher correct call rate. CONCLUSION: Radiology residency programs may be deficient in teaching residents to accurately recognize and report child abuse. This deficiency has potential implications for programs where a radiology attending is not present after hours as it raises the concern that child abuse may be missed by residents taking independent call. These data further question whether graduating radiologists are competent to recognize nonaccidental trauma and demonstrates the need for additional mandatory training during radiology residency.


Assuntos
Internato e Residência , Radiologia , Humanos , Radiografia , Radiologistas , Radiologia/educação
6.
Genes Dev ; 27(10): 1115-31, 2013 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-23699409

RESUMO

Solid tumors exhibit heterogeneous microenvironments, often characterized by limiting concentrations of oxygen (O2), glucose, and other nutrients. How oncogenic mutations alter stress response pathways, metabolism, and cell survival in the face of these challenges is incompletely understood. Here we report that constitutive mammalian target of rapamycin complex 1 (mTORC1) activity renders hypoxic cells dependent on exogenous desaturated lipids, as levels of de novo synthesized unsaturated fatty acids are reduced under low O2. Specifically, we demonstrate that hypoxic Tsc2(-/-) (tuberous sclerosis complex 2(-/-)) cells deprived of serum lipids exhibit a magnified unfolded protein response (UPR) but fail to appropriately expand their endoplasmic reticulum (ER), leading to inositol-requiring protein-1 (IRE1)-dependent cell death that can be reversed by the addition of unsaturated lipids. UPR activation and apoptosis were also detected in Tsc2-deficient kidney tumors. Importantly, we observed this phenotype in multiple human cancer cell lines and suggest that cells committed to unregulated growth within ischemic tumor microenvironments are unable to balance lipid and protein synthesis due to a critical limitation in desaturated lipids.


Assuntos
Hipóxia Celular , Fibroblastos/metabolismo , Metabolismo dos Lipídeos , Lipídeos/química , Neoplasias/metabolismo , Proteínas/metabolismo , Animais , Antígenos Transformantes de Poliomavirus/metabolismo , Autofagia/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Transformação Celular Neoplásica , Estresse do Retículo Endoplasmático , Endorribonucleases/deficiência , Endorribonucleases/genética , Metabolismo Energético , Fibroblastos/efeitos dos fármacos , Fibroblastos/patologia , Humanos , Neoplasias Renais/metabolismo , Neoplasias Renais/patologia , Metabolismo dos Lipídeos/efeitos dos fármacos , Lipídeos/biossíntese , Lipídeos/sangue , Lipídeos/farmacologia , Alvo Mecanístico do Complexo 1 de Rapamicina , Proteínas de Membrana/deficiência , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Camundongos , Complexos Multiproteicos , Neoplasias/patologia , Oxigênio/metabolismo , Oxigênio/farmacologia , Proteínas Serina-Treonina Quinases/deficiência , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Soro , Serina-Treonina Quinases TOR , Proteína 2 do Complexo Esclerose Tuberosa , Microambiente Tumoral , Proteína Supressora de Tumor p53/deficiência , Proteína Supressora de Tumor p53/genética , Proteínas Supressoras de Tumor/deficiência , Proteínas Supressoras de Tumor/genética , Resposta a Proteínas não Dobradas
7.
Nature ; 513(7517): 251-5, 2014 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-25043030

RESUMO

Clear cell renal cell carcinoma (ccRCC), the most common form of kidney cancer, is characterized by elevated glycogen levels and fat deposition. These consistent metabolic alterations are associated with normoxic stabilization of hypoxia-inducible factors (HIFs) secondary to von Hippel-Lindau (VHL) mutations that occur in over 90% of ccRCC tumours. However, kidney-specific VHL deletion in mice fails to elicit ccRCC-specific metabolic phenotypes and tumour formation, suggesting that additional mechanisms are essential. Recent large-scale sequencing analyses revealed the loss of several chromatin remodelling enzymes in a subset of ccRCC (these included polybromo-1, SET domain containing 2 and BRCA1-associated protein-1, among others), indicating that epigenetic perturbations are probably important contributors to the natural history of this disease. Here we used an integrative approach comprising pan-metabolomic profiling and metabolic gene set analysis and determined that the gluconeogenic enzyme fructose-1,6-bisphosphatase 1 (FBP1) is uniformly depleted in over six hundred ccRCC tumours examined. Notably, the human FBP1 locus resides on chromosome 9q22, the loss of which is associated with poor prognosis for ccRCC patients. Our data further indicate that FBP1 inhibits ccRCC progression through two distinct mechanisms. First, FBP1 antagonizes glycolytic flux in renal tubular epithelial cells, the presumptive ccRCC cell of origin, thereby inhibiting a potential Warburg effect. Second, in pVHL (the protein encoded by the VHL gene)-deficient ccRCC cells, FBP1 restrains cell proliferation, glycolysis and the pentose phosphate pathway in a catalytic-activity-independent manner, by inhibiting nuclear HIF function via direct interaction with the HIF inhibitory domain. This unique dual function of the FBP1 protein explains its ubiquitous loss in ccRCC, distinguishing FBP1 from previously identified tumour suppressors that are not consistently mutated in all tumours.


Assuntos
Carcinoma de Células Renais/enzimologia , Frutose-Bifosfatase/metabolismo , Neoplasias Renais/enzimologia , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Carcinoma de Células Renais/genética , Carcinoma de Células Renais/fisiopatologia , Linhagem Celular , Linhagem Celular Tumoral , Proliferação de Células , Progressão da Doença , Células Epiteliais/metabolismo , Frutose-Bifosfatase/química , Frutose-Bifosfatase/genética , Glicólise , Humanos , Neoplasias Renais/genética , Neoplasias Renais/fisiopatologia , Modelos Moleculares , NADP/metabolismo , Estrutura Terciária de Proteína , Suínos
8.
Nature ; 493(7434): 689-93, 2013 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-23334421

RESUMO

Cellular senescence both protects multicellular organisms from cancer and contributes to their ageing. The pre-eminent tumour suppressor p53 has an important role in the induction and maintenance of senescence, but how it carries out this function remains poorly understood. In addition, although increasing evidence supports the idea that metabolic changes underlie many cell-fate decisions and p53-mediated tumour suppression, few connections between metabolic enzymes and senescence have been established. Here we describe a new mechanism by which p53 links these functions. We show that p53 represses the expression of the tricarboxylic-acid-cycle-associated malic enzymes ME1 and ME2 in human and mouse cells. Both malic enzymes are important for NADPH production, lipogenesis and glutamine metabolism, but ME2 has a more profound effect. Through the inhibition of malic enzymes, p53 regulates cell metabolism and proliferation. Downregulation of ME1 and ME2 reciprocally activates p53 through distinct MDM2- and AMP-activated protein kinase-mediated mechanisms in a feed-forward manner, bolstering this pathway and enhancing p53 activation. Downregulation of ME1 and ME2 also modulates the outcome of p53 activation, leading to strong induction of senescence, but not apoptosis, whereas enforced expression of either malic enzyme suppresses senescence. Our findings define physiological functions of malic enzymes, demonstrate a positive-feedback mechanism that sustains p53 activation, and reveal a connection between metabolism and senescence mediated by p53.


Assuntos
Regulação da Expressão Gênica , Malato Desidrogenase (NADP+)/metabolismo , Malato Desidrogenase/metabolismo , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Células 3T3 , Animais , Antibióticos Antineoplásicos/farmacologia , Linhagem Celular , Linhagem Celular Tumoral , Proliferação de Células , Senescência Celular/fisiologia , Doxorrubicina/farmacologia , Técnicas de Silenciamento de Genes , Inativação Gênica , Glucose/metabolismo , Glutamina/metabolismo , Células HCT116 , Humanos , Lipídeos/biossíntese , Malato Desidrogenase/genética , Malato Desidrogenase (NADP+)/genética , Camundongos , NADP/metabolismo , Ligação Proteica/efeitos dos fármacos
9.
Genes Dev ; 24(24): 2784-99, 2010 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-21106670

RESUMO

Glucose and glutamine serve as the two primary carbon sources in proliferating cells, and uptake of both nutrients is directed by growth factor signaling. Although either glucose or glutamine can potentially support mitochondrial tricarboxylic acid (TCA) cycle integrity and ATP production, we found that glucose deprivation led to a marked reduction in glutamine uptake and progressive cellular atrophy in multiple mammalian cell types. Despite the continuous presence of growth factor and an abundant supply of extracellular glutamine, interleukin-3 (IL-3)-dependent cells were unable to maintain TCA cycle metabolite pools or receptor-dependent signal transduction when deprived of glucose. This was due at least in part to down-regulation of IL-3 receptor α (IL-3Rα) surface expression in the absence of glucose. Treatment of glucose-starved cells with N-acetylglucosamine (GlcNAc) to maintain hexosamine biosynthesis restored mitochondrial metabolism and cell growth by promoting IL-3-dependent glutamine uptake and metabolism. Thus, glucose metabolism through the hexosamine biosynthetic pathway is required to sustain sufficient growth factor signaling and glutamine uptake to support cell growth and survival.


Assuntos
Glucose/metabolismo , Glutamina/metabolismo , Hexosaminas/biossíntese , Redes e Vias Metabólicas , Acetilglucosamina/farmacologia , Animais , Atrofia , Transporte Biológico , Sobrevivência Celular , Ciclo do Ácido Cítrico , Peptídeos e Proteínas de Sinalização Intercelular/farmacologia , Interleucina-3 , Camundongos , Transdução de Sinais
10.
J Biol Chem ; 291(10): 5157-71, 2016 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-26703469

RESUMO

A network model for the determination of tumor metabolic fluxes from (13)C NMR kinetic isotopomer data has been developed and validated with perfused human DB-1 melanoma cells carrying the BRAF V600E mutation, which promotes oxidative metabolism. The model generated in the bonded cumomer formalism describes key pathways of tumor intermediary metabolism and yields dynamic curves for positional isotopic enrichment and spin-spin multiplets. Cells attached to microcarrier beads were perfused with 26 mm [1,6-(13)C2]glucose under normoxic conditions at 37 °C and monitored by (13)C NMR spectroscopy. Excellent agreement between model-predicted and experimentally measured values of the rates of oxygen and glucose consumption, lactate production, and glutamate pool size validated the model. ATP production by glycolytic and oxidative metabolism were compared under hyperglycemic normoxic conditions; 51% of the energy came from oxidative phosphorylation and 49% came from glycolysis. Even though the rate of glutamine uptake was ∼ 50% of the tricarboxylic acid cycle flux, the rate of ATP production from glutamine was essentially zero (no glutaminolysis). De novo fatty acid production was ∼ 6% of the tricarboxylic acid cycle flux. The oxidative pentose phosphate pathway flux was 3.6% of glycolysis, and three non-oxidative pentose phosphate pathway exchange fluxes were calculated. Mass spectrometry was then used to compare fluxes through various pathways under hyperglycemic (26 mm) and euglycemic (5 mm) conditions. Under euglycemic conditions glutamine uptake doubled, but ATP production from glutamine did not significantly change. A new parameter measuring the Warburg effect (the ratio of lactate production flux to pyruvate influx through the mitochondrial pyruvate carrier) was calculated to be 21, close to upper limit of oxidative metabolism.


Assuntos
Melanoma/metabolismo , Fosforilação Oxidativa , Trifosfato de Adenosina/metabolismo , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Linhagem Celular Tumoral , Ciclo do Ácido Cítrico , Glucose/metabolismo , Glutamina/metabolismo , Humanos , Modelos Teóricos , Mutação de Sentido Incorreto , Oxigênio/metabolismo , Proteínas Proto-Oncogênicas B-raf/genética
11.
Cancer Control ; 23(3): 208-12, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27556660

RESUMO

BACKGROUND: Depending on the extent of disease, squamous cell carcinoma (SCC) of the glottis is managed with surgery, radiotherapy (RT), or a combination of these modalities. Patients with advanced disease may receive concomitant chemotherapy in conjunction with definitive or postoperative RT. METHODS: The treatment policies of the University of Florida and patient outcomes are reviewed. RESULTS: The likelihood of cure after RT for carcinoma in situ (Tis) to T2 glottic SCC varies from 70% to 94% depending on tumor stage. Consideration should be given to adding weekly cisplatin for patients with T2b SCC because of the high local recurrence rate after RT alone. The probability of cure is about 65% to 80% for select low-volume (≤ 3.5 cc) T3 to T4 glottic SCC after RT. These patients should be considered for concomitant weekly cisplatin. Higher-volume tumors, particularly those with airway compromise, should be treated with laryngectomy and postoperative RT. CONCLUSION: Definitive RT is an excellent treatment for select patients with laryngeal cancer.


Assuntos
Carcinoma de Células Escamosas/radioterapia , Glote/patologia , Neoplasias Laríngeas/radioterapia , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/cirurgia , Feminino , Humanos , Neoplasias Laríngeas/patologia , Neoplasias Laríngeas/cirurgia , Masculino , Resultado do Tratamento
12.
Proc Natl Acad Sci U S A ; 109(18): 6904-9, 2012 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-22509023

RESUMO

Despite the fact that most cancer cells display high glycolytic activity, cancer cells selectively express the less active M2 isoform of pyruvate kinase (PKM2). Here we demonstrate that PKM2 expression makes a critical regulatory contribution to the serine synthetic pathway. In the absence of serine, an allosteric activator of PKM2, glycolytic efflux to lactate is significantly reduced in PKM2-expressing cells. This inhibition of PKM2 results in the accumulation of glycolytic intermediates that feed into serine synthesis. As a consequence, PKM2-expressing cells can maintain mammalian target of rapamycin complex 1 activity and proliferate in serine-depleted medium, but PKM1-expressing cells cannot. Cellular detection of serine depletion depends on general control nonderepressible 2 kinase-activating transcription factor 4 (GCN2-ATF4) pathway activation and results in increased expression of enzymes required for serine synthesis from the accumulating glycolytic precursors. These findings suggest that tumor cells use serine-dependent regulation of PKM2 and GCN2 to modulate the flux of glycolytic intermediates in support of cell proliferation.


Assuntos
Proliferação de Células , Proteínas/metabolismo , Piruvato Quinase/metabolismo , Serina/biossíntese , Fator 4 Ativador da Transcrição/metabolismo , Animais , Linhagem Celular Tumoral , Glicólise , Humanos , Cinética , Alvo Mecanístico do Complexo 1 de Rapamicina , Camundongos , Modelos Biológicos , Complexos Multiproteicos , Proteínas Serina-Treonina Quinases/metabolismo , Piruvato Quinase/antagonistas & inibidores , Piruvato Quinase/genética , RNA Interferente Pequeno/genética , Transdução de Sinais , Serina-Treonina Quinases TOR
13.
J Imaging Inform Med ; 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38937342

RESUMO

Early and accurate detection of cervical lymph nodes is essential for the optimal management and staging of patients with head and neck malignancies. Pilot studies have demonstrated the potential for radiomic and artificial intelligence (AI) approaches in increasing diagnostic accuracy for the detection and classification of lymph nodes, but implementation of many of these approaches in real-world clinical settings would necessitate an automated lymph node segmentation pipeline as a first step. In this study, we aim to develop a non-invasive deep learning (DL) algorithm for detecting and automatically segmenting cervical lymph nodes in 25,119 CT slices from 221 normal neck contrast-enhanced CT scans from patients without head and neck cancer. We focused on the most challenging task of segmentation of small lymph nodes, evaluated multiple architectures, and employed U-Net and our adapted spatial context network to detect and segment small lymph nodes measuring 5-10 mm. The developed algorithm achieved a Dice score of 0.8084, indicating its effectiveness in detecting and segmenting cervical lymph nodes despite their small size. A segmentation framework successful in this task could represent an essential initial block for future algorithms aiming to evaluate small objects such as lymph nodes in different body parts, including small lymph nodes looking normal to the naked human eye but harboring early nodal metastases.

14.
Curr Probl Diagn Radiol ; 53(1): 22-26, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37690966

RESUMO

RATIONALE AND OBJECTIVES: This study explores the implementation and efficacy of an online, interactive, case-based radiology education tool, Wisdom in Diagnostic Imaging (WIDI) Case-Based Intro to Radiology (CBIR). We hypothesize that the WIDI CBIR platform would enhance radiology teaching, foster critical thinking, and provide a comprehensive curriculum in imaging interpretation and utilization. MATERIALS AND METHODS: A focus group consisting of 1 undergraduate, 7 medical students, 9 physician assistant students, and 3 PhD students participated in this study. We tested 3 different teaching methods: a didactic approach without WIDI, a proctored didactic approach using WIDI, and a flipped classroom approach using WIDI. An online survey was conducted to assess student preference and feedback on these methods and the use of WIDI in their curriculum. RESULTS: Most students preferred the proctored didactic approach with WIDI. They reported that the platform complemented their curriculum and encouraged critical thinking. The modules covered adequate clinical and imaging details and enhanced their skills in imaging interpretation. Despite the limitations of a small sample size and reliance on self-reported outcomes, this study indicates that the WIDI platform could be integrated into PA and medical school curricula throughout the US, offering a standardized radiology curriculum. CONCLUSION: The UF WIDI appears to be a promising tool for modernizing radiology education, improving imaging interpretation skills, and enhancing appropriate imaging selection among nonradiologist medical learners. WIDI offers case-based education in imaging use, workflow, search-pattern selection, and interpretation of common radiological findings, potentially bridging the gap in radiology education. Further research and larger studies are required to assess the long-term impact on performance and clinical practice.


Assuntos
Instrução por Computador , Educação de Graduação em Medicina , Radiologia , Estudantes de Medicina , Humanos , Currículo , Radiologia/educação , Radiografia , Avaliação Educacional , Educação de Graduação em Medicina/métodos
15.
Semin Roentgenol ; 58(2): 158-169, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37087136

RESUMO

There are many impactful applications of artificial intelligence (AI) in the electronic radiology roundtrip and the patient's journey through the healthcare system that go beyond diagnostic applications. These tools have the potential to improve quality and safety, optimize workflow, increase efficiency, and increase patient satisfaction. In this article, we review the role of AI for process improvement and workflow enhancement which includes applications beginning from the time of order entry, scan acquisition, applications supporting the image interpretation task, and applications supporting tasks after image interpretation such as result communication. These non-diagnostic workflow and process optimization tasks are an important part of the arsenal of potential AI tools that can streamline day to day clinical practice and patient care.


Assuntos
Inteligência Artificial , Radiologia , Humanos , Fluxo de Trabalho , Radiologia/métodos
16.
Expert Rev Anticancer Ther ; 23(12): 1265-1279, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38032181

RESUMO

INTRODUCTION: Artificial intelligence (AI) has the potential to transform oncologic care. There have been significant developments in AI applications in medical imaging and increasing interest in multimodal models. These are likely to enable improved oncologic care through more precise diagnosis, increasingly in a more personalized and less invasive manner. In this review, we provide an overview of the current state and challenges that clinicians, administrative personnel and policy makers need to be aware of and mitigate for the technology to reach its full potential. AREAS COVERED: The article provides a brief targeted overview of AI, a high-level review of the current state and future potential AI applications in diagnostic radiology and to a lesser extent digital pathology, focusing on oncologic applications. This is followed by a discussion of emerging approaches, including multimodal models. The article concludes with a discussion of technical, regulatory challenges and infrastructure needs for AI to realize its full potential. EXPERT OPINION: There is a large volume of promising research, and steadily increasing commercially available tools using AI. For the most advanced and promising precision diagnostic applications of AI to be used clinically, robust and comprehensive quality monitoring systems and informatics platforms will likely be required.


Assuntos
Inteligência Artificial , Neoplasias , Humanos , Diagnóstico por Imagem , Oncologia , Previsões , Cuidados Paliativos , Neoplasias/diagnóstico por imagem , Neoplasias/terapia
17.
Semin Roentgenol ; 58(2): 152-157, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37087135

RESUMO

Health informatics and artificial intelligence (AI) are expected to transform the healthcare enterprise and the future practice of radiology. There is an increasing body of literature on radiomics and deep learning/AI applications in medical imaging. There are also a steadily increasing number of FDA cleared AI applications in radiology. It is therefore essential for radiologists to have a basic understanding of these approaches, whether in academia or private practice. In this article, we will provide an overview of the field and familiarize the readers with the fundamental concepts behind these approaches.


Assuntos
Inteligência Artificial , Radiologia , Humanos , Radiologistas , Radiologia/métodos , Radiografia , Previsões
18.
Proc Natl Acad Sci U S A ; 106(51): 21660-5, 2009 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-19995986

RESUMO

Tumor cells are metabolically reprogrammed to fuel cell proliferation. Most transformed cells take up high levels of glucose and produce ATP through aerobic glycolysis. In cells exhibiting aerobic glycolysis, a significant fraction of glucose carbon is also directed into de novo lipogenesis and nucleotide biosynthesis. The glucose-responsive transcription factor carbohydrate responsive element binding protein (ChREBP) was previously shown to be important for redirecting glucose metabolism in support of lipogenesis in nonproliferating hepatocytes. However, whether it plays a more generalized role in reprogramming metabolism during cell proliferation has not been examined. Here, we demonstrated that the expression of ChREBP can be induced in response to mitogenic stimulation and that the induction of ChREBP is required for efficient cell proliferation. Suppression of ChREBP resulted in diminished aerobic glycolysis, de novo lipogenesis, and nucleotide biosynthesis, but stimulated mitochondrial respiration, suggesting a metabolic switch from aerobic glycolysis to oxidative phosphorylation. Cells in which ChREBP was suppressed by RNAi exhibited p53 activation and cell cycle arrest. In vivo, suppression of ChREBP led to a p53-dependent reduction in tumor growth. These results demonstrate that ChREBP plays a key role both in redirecting glucose metabolism to anabolic pathways and suppressing p53 activity.


Assuntos
Anabolizantes/metabolismo , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/fisiologia , Proliferação de Células , Glucose/farmacologia , Animais , Sequência de Bases , Ciclo Celular , Linhagem Celular Tumoral , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Humanos , Masculino , Camundongos , Camundongos Nus , RNA Interferente Pequeno , Transplante Heterólogo , Proteína Supressora de Tumor p53/metabolismo
19.
Am J Otolaryngol ; 33(4): 447-54, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22185685

RESUMO

PURPOSE: The aim of the study was to update the experience treating cutaneous squamous cell and basal cell carcinomas of the head and neck with incidental or clinical perineural invasion (PNI) with radiotherapy (RT). MATERIALS AND METHODS: From 1965 to 2007, 216 patients received RT alone or with surgery and/or chemotherapy. RESULTS: The 5-year overall, cause-specific, and disease-free survivals for incidental and clinical PNIs were 55% vs 54%, 73% vs 64%, and 67% vs 51%. The 5-year local control, local-regional control, and freedom from distant metastases for incidental and clinical PNIs were 80% vs 54%, 70% vs 51%, and 90% vs 94%. On univariate and multivariate (P = .0038 and .0047) analyses, clinical PNI was a poor prognostic factor for local control. The rates of grade 3 or higher complication in the incidental and clinical PNI groups were 16% and 36%, respectively. CONCLUSIONS: Radiotherapy plays a critical role in the treatment of this disease. Clinical PNI should be adequately irradiated to include the involved nerves to the skull base.


Assuntos
Carcinoma Basocelular/patologia , Carcinoma de Células Escamosas/patologia , Neoplasias do Sistema Nervoso Periférico/patologia , Neoplasias Cutâneas/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Basocelular/terapia , Carcinoma de Células Escamosas/terapia , Terapia Combinada , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Estadiamento de Neoplasias , Prognóstico , Modelos de Riscos Proporcionais , Neoplasias Cutâneas/terapia , Taxa de Sobrevida
20.
European J Pediatr Surg Rep ; 10(1): e98-e101, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35911496

RESUMO

A 10-year-old male presented with symptoms in his right shoulder indicative of adhesive capsulitis. Radiographic films did not demonstrate any osseous abnormalities. Magnetic resonance imaging demonstrated the presence of an eccentric lesion within the coracoid process consistent with an osteoid osteoma. Six months after surgical removal the patient is back to full activities. For the pediatric population, surgeons must always consider diagnoses that could alter a patient's growth or result in long-term disability. In particular, an atypical presentation of musculoskeletal disease in a pediatric patient presenting with a disease that typically is seen in the older population warrants further workup.

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