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Background and purpose: Magnetic resonance imaging (MRI)-to-computed tomography (CT) synthesis is essential in MRI-only radiotherapy workflows, particularly through deep learning techniques known for their accuracy. However, current supervised methods are limited to specific center's learnings and depend on registration precision. The aim of this study was to evaluate the accuracy of unsupervised and supervised approaches in the context of prostate MRI-to-CT generation for radiotherapy dose calculation. Methods: CT/MRI image pairs from 99 prostate cancer patients across three different centers were used. A comparison between supervised and unsupervised conditional Generative Adversarial Networks (cGAN) was conducted. Unsupervised training incorporates a style transfer method with. Content and Style Representation for Enhanced Perceptual synthesis (CREPs) loss. For dose evaluation, the photon prescription dose was 60 Gy delivered in volumetric modulated arc therapy (VMAT). Imaging endpoint for sCT evaluation was Mean Absolute Error (MAE). Dosimetric endpoints included absolute dose differences and gamma analysis between CT and sCT dose calculations. Results: The unsupervised paired network exhibited the highest accuracy for the body with a MAE at 33.6 HU, the highest MAE was 45.5 HU obtained with unsupervised unpaired learning. All architectures provided clinically acceptable results for dose calculation with gamma pass rates above 94 % (1 % 1 mm 10 %). Conclusions: This study shows that multicenter data can produce accurate sCTs via unsupervised learning, eliminating CT-MRI registration. The sCTs not only matched HU values but also enabled precise dose calculations, suggesting their potential for wider use in MRI-only radiotherapy workflows.
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Understanding the pathophysiology of myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is critical for advancing treatment options. This review explores the novel hypothesis that a herpesvirus infection of endothelial cells (ECs) may underlie ME/CFS symptomatology. We review evidence linking herpesviruses to persistent EC infection and the implications for endothelial dysfunction, encompassing blood flow regulation, coagulation, and cognitive impairment-symptoms consistent with ME/CFS and Long COVID. This paper provides a synthesis of current research on herpesvirus latency and reactivation, detailing the impact on ECs and subsequent systemic complications, including latent modulation and long-term maladaptation. We suggest that the chronicity of ME/CFS symptoms and the multisystemic nature of the disease may be partly attributable to herpesvirus-induced endothelial maladaptation. Our conclusions underscore the necessity for further investigation into the prevalence and load of herpesvirus infection within the ECs of ME/CFS patients. This review offers conceptual advances by proposing an endothelial infection model as a systemic mechanism contributing to ME/CFS, steering future research toward potentially unexplored avenues in understanding and treating this complex syndrome.
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Células Endoteliais , Síndrome de Fadiga Crônica , Infecções por Herpesviridae , Humanos , Células Endoteliais/virologia , Síndrome de Fadiga Crônica/virologia , Síndrome de Fadiga Crônica/fisiopatologia , Herpesviridae/fisiologia , Infecções por Herpesviridae/virologia , Latência Viral , Síndrome de COVID-19 Pós-Aguda/patologia , Síndrome de COVID-19 Pós-Aguda/fisiopatologiaRESUMO
Background and Purpose: Addressing the need for accurate dose calculation in MRI-only radiotherapy, the generation of synthetic Computed Tomography (sCT) from MRI has emerged. Deep learning (DL) techniques, have shown promising results in achieving high sCT accuracies. However, existing sCT synthesis methods are often center-specific, posing a challenge to their generalizability. To overcome this limitation, recent studies have proposed approaches, such as multicenter training . Material and methods: The purpose of this work was to propose a multicenter sCT synthesis by DL, using a 2D cycle-GAN on 128 prostate cancer patients, from four different centers. Four cases were compared: monocenter cases, monocenter training and test on another center, multicenter trainings and a test on a center not included in the training and multicenter trainings with an included center in the test. Trainings were performed using 20 patients. sCT accuracy evaluation was performed using Mean Absolute Error, Mean Error and Peak-Signal-to-Noise-Ratio. Dose accuracy was assessed with gamma index and Dose Volume Histogram comparison. Results: Qualitative, quantitative and dose results show that the accuracy of sCTs for monocenter trainings and multicenter trainings using a seen center in the test did not differ significantly. However, when the test involved an unseen center, the sCT quality was inferior. Conclusions: The aim of this work was to propose generalizable multicenter training for MR-to-CT synthesis. It was shown that only a few data from one center included in the training cohort allows sCT accuracy equivalent to a monocenter study.
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Introduction: For radiotherapy based solely on magnetic resonance imaging (MRI), generating synthetic computed tomography scans (sCT) from MRI is essential for dose calculation. The use of deep learning (DL) methods to generate sCT from MRI has shown encouraging results if the MRI images used for training the deep learning network and the MRI images for sCT generation come from the same MRI device. The objective of this study was to create and evaluate a generic DL model capable of generating sCTs from various MRI devices for prostate radiotherapy. Materials and methods: In total, 90 patients from three centers (30 CT-MR prostate pairs/center) underwent treatment using volumetric modulated arc therapy for prostate cancer (PCa) (60 Gy in 20 fractions). T2 MRI images were acquired in addition to computed tomography (CT) images for treatment planning. The DL model was a 2D supervised conditional generative adversarial network (Pix2Pix). Patient images underwent preprocessing steps, including nonrigid registration. Seven different supervised models were trained, incorporating patients from one, two, or three centers. Each model was trained on 24 CT-MR prostate pairs. A generic model was trained using patients from all three centers. To compare sCT and CT, the mean absolute error in Hounsfield units was calculated for the entire pelvis, prostate, bladder, rectum, and bones. For dose analysis, mean dose differences of D 99% for CTV, V 95% for PTV, Dmax for rectum and bladder, and 3D gamma analysis (local, 1%/1 mm) were calculated from CT and sCT. Furthermore, Wilcoxon tests were performed to compare the image and dose results obtained with the generic model to those with the other trained models. Results: Considering the image results for the entire pelvis, when the data used for the test comes from the same center as the data used for training, the results were not significantly different from the generic model. Absolute dose differences were less than 1 Gy for the CTV D 99% for every trained model and center. The gamma analysis results showed nonsignificant differences between the generic and monocentric models. Conclusion: The accuracy of sCT, in terms of image and dose, is equivalent to whether MRI images are generated using the generic model or the monocentric model. The generic model, using only eight MRI-CT pairs per center, offers robust sCT generation, facilitating PCa MRI-only radiotherapy for routine clinical use.
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Radiation therapy is moving from CT based to MRI guided planning, particularly for soft tissue anatomy. An important requirement of this new workflow is the generation of synthetic-CT (sCT) from MRI to enable treatment dose calculations. Automatic methods to determine the acceptable range of CT Hounsfield Unit (HU) uncertainties to avoid dose distribution errors is thus a key step toward safe MRI-only radiotherapy. This work has analysed the effects of controlled errors introduced in CT scans on the delivered radiation dose for prostate cancer patients. Spearman correlation coefficient has been computed, and a global sensitivity analysis performed following the Morris screening method. This allows the classification of different error factors according to their impact on the dose at the isocentre. sCT HU estimation errors in the bladder appeared to be the least influential factor, and sCT quality assessment should not only focus on organs surrounding the radiation target, as errors in other soft tissue may significantly impact the dose in the target volume. This methodology links dose and intensity-based metrics, and is the first step to define a threshold of acceptability of HU uncertainties for accurate dose planning.
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Próstata , Neoplasias da Próstata , Masculino , Humanos , Próstata/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/radioterapia , Bexiga Urinária , Imageamento por Ressonância Magnética/métodosRESUMO
This study aimed to analyze the molecular characteristics of oral epithelial dysplasia (OED), highlighting the pathways and variants of genes that are frequently mutated in oral squamous cell carcinoma (OSCC) and other cancers. Ten archival OED cases were retrieved for retrospective clinicopathological analysis and exome sequencing. Comparative genomic analysis was performed between high-grade dysplasia (HGD) and low-grade dysplasia (LGD), focusing on 57 well-known cancer genes, of which 10 were previously described as the most mutated in OSCC. HGD cases had significantly more variants; however, a similar mutational landscape to OSCC was observed in both groups. CASP8+FAT1/HRAS, TP53, and miscellaneous molecular signatures were also present. FAT1 is the gene that is most affected by pathogenic variants. Hierarchical divisive clustering showed division between the two groups: "HGD-like cluster" with 4HGD and 2LGD and "LGD-like cluster" with 4 LGD. MLL4 pathogenic variants were exclusively in the "LGD-like cluster". TP53 was affected in one case of HGD; however, its pathway was usually altered. We describe new insights into the genetic basis of epithelial malignant transformation by genomic analysis, highlighting those associated with FAT1 and TP53. Some LGDs presented a similar mutational landscape to HGD after cluster analysis. Perhaps molecular alterations have not yet been reflected in histomorphology. The relative risk of malignant transformation in this molecular subgroup should be addressed in future studies.
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Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Neoplasias Bucais , Humanos , Carcinoma de Células Escamosas/genética , Estudos Retrospectivos , Neoplasias Bucais/genética , Mapeamento Cromossômico , Carcinoma de Células Escamosas de Cabeça e PescoçoRESUMO
Background and Purpose: Acute ischemic stroke (AIS) and depression are the major causes of disability and decreased quality of life worldwide. Psychiatric disorders are common after stroke, especially post-stroke depression (PSD), which affects one-third of survivors. Although frequent, little is known about the real complexity of the pathophysiology and the factors associated with PSD. Methods: This research aimed to provide data about risk factors and predictors of PSD 90 days after AIS. A cohort study was conducted in a tertiary stroke center located in southern Brazil. We interviewed 148 patients with AIS who were consecutively hospitalized between January 2020 and January 2021. The Hospital Anxiety and Depression Scale (HADS) was applied during hospitalization and at follow-up 90 days after AIS. Furthermore, sociodemographic, clinical, and radiological variables were investigated. Predictive factors were assessed using univariate and multivariate linear regression. The impact of the COVID-19 pandemic on the data was also evaluated. Results: The frequency of PSD 90 days after AIS was 33.9%. In-hospital symptoms of depression and anxiety each represented a 2-fold risk for PSD at follow-up. Furthermore, the HADS - anxiety score 90 days after AIS was strongly associated with the HADS - depression value 90 days after stroke (R: .71; B: .56; P < .01). Conclusions: The present study highlighted a noteworthy frequency of PSD 90 days after AIS. Psychiatric variables during hospitalization and in the follow-up appeared to be the leading associated factors with PSD. These data might support the determination of which patients require more psychiatric management.
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Introducción y objetivos El acceso femoral es la vía vascular mayoritariamente utilizada en intervenciones coronarias percutáneas de desobstrucción de oclusiones totales crónicas (ICP-OTC). El objetivo de este estudio fue evaluar la viabilidad y seguridad del acceso radial en un programa de ICP-OTC y su impacto sobre el resultado clínico y angiográfico y la duración de la estancia hospitalaria. Métodos Estudio multicéntrico retrospectivo de cohortes en el que se incluyeron de forma consecutiva 2.550 procedimientos de ICP-OTC con información precisa sobre acceso vascular. Un total de 896 casos se realizaron por acceso radial puro y 1.654 se realizaron con al menos una punción femoral. Se analizaron datos clínicos y angiográficos. Resultados La edad media fue de 66,3±11,4 años. La puntuación Japan-chronic total occlusion (J-CTO) fue similar en ambos grupos (2,7±0,3). El éxito del procedimiento se obtuvo en un 79,6% de los procedimientos, 78,2% y 82,1% en la cohorte transfemoral y transradial respectivamente p=0,02). Las complicaciones intrahospitalarias periprocedimiento se observaron en el 5,1% y el 2,3% (p=0,02), con un menor número de complicaciones vasculares dependientes del sitio de punción (2,3% frente a 0,2%, p=0,009). La duración media del ingreso hospitalario fue significativamente menor en el grupo radial (0,89±1,4 frente a 2,2±3,2 días; p<0,001). Conclusiones Un programa de acceso radial para la ICP-OTC es seguro y efectivo para la mayoría de las oclusiones. La estrategia transradial permite un menor número de complicaciones vasculares y una estancia media más corta sin comprometer la tasa de éxito del procedimiento (AU)
Introduction and objectives Transfemoral access is the most frequently used vascular approach in chronic total occlusion percutaneous coronary interventions (CTO-PCI). The aim of this study was to evaluate the safety and feasibility of a transradial access CTO-PCI program and its impact on angiographic and clinical results and length of hospital stay. Methods Retrospective multicenter cohort study including 2550 consecutive CTO-PCI procedures included in a multicenter registry with accurate information on vascular access. A total of 896 procedures were performed as radial-only access while 1654 were performed through at least 1 femoral puncture. Clinical and angiographic data were collected. Results The mean age was 66.3± 11.4 years. The mean Japan-chronic total occlusion score (2.7±0.3) was similar in the 2 groups. Successful revascularization was achieved in 2009 (79.6%) cases, 78.2% and 82.1% in the femoral and radial access cohorts, respectively (P=.002). Periprocedural in-hospital complications were observed in 5.1% and 2.3% (P=.02), with fewer access site-dependant vascular complications in the transradial cohort (2.3% vs 0.2%; P=.009). The mean length of hospital stay was significantly shorter in the transradial access group (0.89±1.4 vs 2.2±3.2 days, P<.001). Conclusions A transradial program for CTO-PCI is safe and effective in most CTO lesions. The transradial strategy has fewer vascular complications and shorter length of hospital stay without compromising the success rate (AU)
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Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Doenças Cardiovasculares , Oclusão Coronária/diagnóstico , Oclusão Coronária/cirurgia , Intervenção Coronária Percutânea , Estudos Retrospectivos , Doença Crônica , Estudos de Coortes , Angiografia Coronária , Estudos de Viabilidade , Artéria Femoral/cirurgia , Artéria Radial/cirurgia , Resultado do TratamentoRESUMO
ME/CFS is a debilitating chronic condition that often develops after viral or bacterial infection. Insight from the study of Long COVID/Post Acute Sequelae of COVID-19 (PASC), the post-viral syndrome associated with SARS-CoV-2 infection, might prove to be useful for understanding pathophysiological mechanisms of ME/CFS. Disease presentation is similar between the two conditions, and a subset of Long COVID patients meet the diagnostic criteria for ME/CFS. Since Long COVID is characterized by significant vascular pathology - including endothelial dysfunction, coagulopathy, and vascular dysregulation - the question of whether or not the same biological abnormalities are of significance in ME/CFS arises. Cardiac abnormalities have for a while now been documented in ME/CFS cohorts, with recent studies demonstrating major deficits in cerebral blood flow, and hence vascular dysregulation. A growing body of research is demonstrating that ME/CFS is accompanied by platelet hyperactivation, anomalous clotting, a procoagulant phenotype, and endothelial dysfunction. Endothelial damage and dysregulated clotting can impair substance exchange between blood and tissues, and result in hypoperfusion, which may contribute to the manifestation of certain ME/CFS symptoms. Here we review the ME/CFS literature to summarize cardiovascular and haematological findings documented in patients with the condition, and, in this context, briefly discuss the potential role of previously-implicated pathogens. Overall, cardiac and haematological abnormalities are present within ME/CFS cohorts. While atherosclerotic heart disease is not significantly associated with ME/CFS, suboptimal cardiovascular function defined by reduced cardiac output, impaired cerebral blood flow, and vascular dysregulation are, and these abnormalities do not appear to be influenced by deconditioning. Rather, these cardiac abnormalities may result from dysfunction in the (autonomic) nervous system. Plenty of recently published studies are demonstrating significant platelet hyperactivity and endothelial dysfunction in ME/CFS, as well as anomalous clotting processes. It is of particular importance to determine to what extent these cardiovascular and haematological abnormalities contribute to symptom severity, and if these two systems can be targeted for therapeutic purposes. Viral reservoirs of herpesviruses exist in ME/CFS, and most likely contribute to cardiovascular and haematological dysfunction directly or indirectly. This review highlights the potential of studying cardiac functioning, the vasculature, and coagulation system in ME/CFS.
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COVID-19 , Síndrome de Fadiga Crônica , Humanos , Síndrome de Fadiga Crônica/etiologia , Síndrome de Fadiga Crônica/diagnóstico , Síndrome de COVID-19 Pós-Aguda , COVID-19/complicações , SARS-CoV-2RESUMO
Abstract Fabry disease (FD) is an X-linked lysosomal storage disorder characterized by reduced or absent activity of the enzyme α-galactosidase A. Due to systemic accumulation of glycolipids, FD phenotype is diverse, and diagnosis may be challenging. Clinical manifestations include small fiber neuropathy, renal dysfunction, cardiac involvement, cerebrovascular disease, among others. In the present study, we describe biopsy proven small fiber neuropathy and subclinical cardiac involvement in two cousins diagnosed with FD secondary to a recently described pathogenic variant, highlighting the importance of diagnostic tools to document organ damage and allow early treatment.
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Abstract This study aimed to analyze the molecular characteristics of oral epithelial dysplasia (OED), highlighting the pathways and variants of genes that are frequently mutated in oral squamous cell carcinoma (OSCC) and other cancers. Ten archival OED cases were retrieved for retrospective clinicopathological analysis and exome sequencing. Comparative genomic analysis was performed between high-grade dysplasia (HGD) and low-grade dysplasia (LGD), focusing on 57 well-known cancer genes, of which 10 were previously described as the most mutated in OSCC. HGD cases had significantly more variants; however, a similar mutational landscape to OSCC was observed in both groups. CASP8+FAT1/HRAS, TP53, and miscellaneous molecular signatures were also present. FAT1 is the gene that is most affected by pathogenic variants. Hierarchical divisive clustering showed division between the two groups: "HGD-like cluster" with 4HGD and 2LGD and "LGD-like cluster" with 4 LGD. MLL4 pathogenic variants were exclusively in the "LGD-like cluster". TP53 was affected in one case of HGD; however, its pathway was usually altered. We describe new insights into the genetic basis of epithelial malignant transformation by genomic analysis, highlighting those associated with FAT1 and TP53. Some LGDs presented a similar mutational landscape to HGD after cluster analysis. Perhaps molecular alterations have not yet been reflected in histomorphology. The relative risk of malignant transformation in this molecular subgroup should be addressed in future studies.
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OBJECTIVES: Ischemic stroke is a remarkable cause of death and disability worldwide. Post-stroke depression (PSD) is the most common psychiatric disturbance after stroke. Despite PSD being a potentially treatable condition, it still requires approaches to improve the early diagnosis. The present study aims to investigate the factors associated and correlated variables associated with PSD during hospitalization. MATERIALS AND METHODS: A retrospective cross-sectional study was conducted in a specialized center of neurology in Santa Catarina, Brazil. 148 patients with acute ischemic stroke hospitalized between January 2020 and February 2021 were included. Sociodemographic, clinical and radiological variables were assessed during hospitalization. The Hospital Anxiety and Depression Scale (HADS) was applied, as well as the National Institute of Health Stroke Scale (NIHSS) and modified Rankin Scale (mRS). Factors associated were investigated through binary logistic regression and continuous variables through correlation tests. RESULTS: The prevalence of PSD during hospitalization was 31.1%. Factors associated with PSD in the acute phase of the stroke were female sex (OR: 2.6; CI 95%: 1.3-5.4; p < 0.01) and post-stroke anxiety during hospitalization (OR: 4.9; CI 95%: 2.3-10.3; p < 0.01). The variables NIHSS, mRS, and stroke area were positively correlated with HADS - depression values. CONCLUSIONS: This research evidenced a high prevalence of PSD in the acute phase of stroke. Despite the study being conducted during the COVID-19 pandemic, the frequency is similar to the non-pandemic periods. The research provided clues to identify and timely treat patients at greater risk of developing PSD during hospitalization.
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COVID-19 , AVC Isquêmico , Acidente Vascular Cerebral , Humanos , Feminino , Masculino , Estudos Transversais , Depressão/epidemiologia , Depressão/etiologia , Depressão/diagnóstico , Estudos Retrospectivos , Pandemias , Fatores de Risco , Acidente Vascular Cerebral/diagnósticoRESUMO
The quality assurance of synthetic CT (sCT) is crucial for safe clinical transfer to an MRI-only radiotherapy planning workflow. The aim of this work is to propose a population-based process assessing local errors in the generation of sCTs and their impact on dose distribution. For the analysis to be anatomically meaningful, a customized interpatient registration method brought the population data to the same coordinate system. Then, the voxel-based process was applied on two sCT generation methods: a bulk-density method and a generative adversarial network. The CT and MRI pairs of 39 patients treated by radiotherapy for prostate cancer were used for sCT generation, and 26 of them with delineated structures were selected for analysis. Voxel-wise errors in sCT compared to CT were assessed for image intensities and dose calculation, and a population-based statistical test was applied to identify the regions where discrepancies were significant. The cumulative histograms of the mean absolute dose error per volume of tissue were computed to give a quantitative indication of the error for each generation method. Accurate interpatient registration was achieved, with mean Dice scores higher than 0.91 for all organs. The proposed method produces three-dimensional maps that precisely show the location of the major discrepancies for both sCT generation methods, highlighting the heterogeneity of image and dose errors for sCT generation methods from MRI across the pelvic anatomy. Hence, this method provides additional information that will assist with both sCT development and quality control for MRI-based planning radiotherapy.
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We have previously demonstrated that platelet-poor plasma (PPP) obtained from patients with Long COVID/Post-Acute Sequelae of COVID-19 (PASC) is characterized by a hypercoagulable state and contains hyperactivated platelets and considerable numbers of already-formed amyloid fibrin(ogen) or fibrinaloid microclots. Due to the substantial overlap in symptoms and etiology between Long COVID/PASC and ME/CFS, we investigated whether coagulopathies reflected in Long COVID/PASC-hypercoagulability, platelet hyperactivation, and fibrinaloid microclot formation-were present in individuals with ME/CFS and gender- and age-matched healthy controls. ME/CFS samples showed significant hypercoagulability as judged by thromboelastography of both whole blood and platelet-poor plasma. The area of plasma images containing fibrinaloid microclots was commonly more than 10-fold greater in untreated PPP from individuals with ME/CFS than in that of healthy controls. A similar difference was found when the plasma samples were treated with thrombin. Using fluorescently labelled PAC-1, which recognizes glycoprotein IIb/IIIa, and CD62P, which binds P-selectin, we observed hyperactivation of platelets in ME/CFS hematocrit samples. Using a quantitative scoring system, the ME/CFS platelets were found to have a mean spreading score of 2.72 ± 1.24 vs. 1.00 (activation with pseudopodia formation) for healthy controls. We conclude that ME/CFS is accompanied by substantial and measurable changes in coagulability, platelet hyperactivation, and fibrinaloid microclot formation. However, the fibrinaloid microclot load was not as great as was previously noted in Long COVID/PASC. Fibrinaloid microclots, in particular, may contribute to many ME/CFS symptoms, such as fatigue, seen in patients with ME/CFS, via the (temporary) blockage of microcapillaries and hence ischemia. Furthermore, fibrinaloid microclots might damage the endothelium. The discovery of these biomarkers represents an important development in ME/CFS research. It also points to possible uses for treatment strategies using known drugs and/or nutraceuticals that target systemic vascular pathology and endothelial inflammation.
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Background: This study represents an additional case of a rare entity and complication of COVID-19. Purpose: To further describe COVID's association with acute hemorrhagic leukoencephalopathy (AHL), a variant of acute disseminated encephalomyelitis. Besides, subsequent neuropsychological evaluation is described. Methods: The present case report describes clinical, laboratory, radiological, and electroencephalographic characteristics of AHL triggered by COVID-19, in addition to outcomes in the neuropsychological findings. Results: Radiologic findings of demyelinating lesions in supratentorial white matter permeated by multiple hemorrhagic foci supported the diagnostic of AHL, reinforced by clinical improvement after corticosteroid therapy. Conclusions: There are few similar cases previously reported, and this case highlights the early diagnosis and prompt treatment looking forward to better outcomes in AHL. Further studies are needed to elucidate the involved pathophysiological mechanisms.
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BACKGROUND: COVID-19 pandemic directly impacted the request for hospital care and medical assistance for several diseases worldwide, as occurred with acute ischemic stroke. The present study sought to compare the incidence and severity of acute ischemic stroke (AIS), in addition to sociodemographic, clinical, and radiological characteristics of patients hospitalized in the prepandemic (2018-2019) and pandemic (2020-2021) eras. METHODS: An incidence case-control, observational, and analytical research was carried out in the Stroke Unit of Hospital Governador Celso Ramos, Florianopolis, Santa Catarina, Brazil, including 171 patients admitted with acute ischemic stroke from April 2018 to April 2019 (prepandemic era) and 148 patients between January 2020 and January 2021 (during pandemic). RESULTS: The mean incidence of AIS hospital admissions was significantly lower in the pandemic period (CI 95%, 0.2 to 5.6; p = 0.04), being lower in the lockdown periods and when the incidence of new COVID-19 cases increased. Besides, referring to AIS severity, the mean areas of AIS were larger during the pandemic period (p < 0.01), especially in August, September, December, and January (p < 0.05). Sociodemographic and clinical variables did not show any difference between the two periods of the study. CONCLUSIONS: Hospital admissions for AIS decreased in the COVID-19 pandemic, mostly during months of higher incidences of new COVID-19 cases. When the incidence of admissions diminished, an increase in the severity of AIS was observed, characterized by larger areas. These findings might contribute to other similar referral centers in managing public policies related to stroke.
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COVID-19 , AVC Isquêmico , Acidente Vascular Cerebral , Brasil/epidemiologia , Controle de Doenças Transmissíveis , Humanos , AVC Isquêmico/epidemiologia , Pandemias , Estudos Retrospectivos , Fatores de Risco , SARS-CoV-2 , Acidente Vascular Cerebral/epidemiologiaRESUMO
PURPOSE: In radiotherapy, MRI is used for target volume and organs-at-risk delineation for its superior soft-tissue contrast as compared to CT imaging. However, MRI does not provide the electron density of tissue necessary for dose calculation. Several methods of synthetic-CT (sCT) generation from MRI data have been developed for radiotherapy dose calculation. This work reviewed deep learning (DL) sCT generation methods and their associated image and dose evaluation, in the context of MRI-based dose calculation. METHODS: We searched the PubMed and ScienceDirect electronic databases from January 2010 to March 2021. For each paper, several items were screened and compiled in figures and tables. RESULTS: This review included 57 studies. The DL methods were either generator-only based (45% of the reviewed studies), or generative adversarial network (GAN) architecture and its variants (55% of the reviewed studies). The brain and pelvis were the most commonly investigated anatomical localizations (39% and 28% of the reviewed studies, respectively), and more rarely, the head-and-neck (H&N) (15%), abdomen (10%), liver (5%) or breast (3%). All the studies performed an image evaluation of sCTs with a diversity of metrics, with only 36 studies performing dosimetric evaluations of sCT. CONCLUSIONS: The median mean absolute errors were around 76 HU for the brain and H&N sCTs and 40 HU for the pelvis sCTs. For the brain, the mean dose difference between the sCT and the reference CT was <2%. For the H&N and pelvis, the mean dose difference was below 1% in most of the studies. Recent GAN architectures have advantages compared to generator-only, but no superiority was found in term of image or dose sCT uncertainties. Key challenges of DL-based sCT generation methods from MRI in radiotherapy is the management of movement for abdominal and thoracic localizations, the standardization of sCT evaluation, and the investigation of multicenter impacts.
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Aprendizado Profundo , Imageamento por Ressonância Magnética , Estudos Multicêntricos como Assunto , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador , Tomografia Computadorizada por Raios XRESUMO
Pathogenic germline variants in DMD gene, which encodes the well-known cytoskeletal protein named dystrophin, are associated with a wide range of dystrophinopathies disorders, such as Duchenne muscular dystrophy (DMD, severe form), Becker muscular dystrophy (BMD, mild form) and intermediate muscular dystrophy (IMD). Muscle biopsy, immunohistochemistry, molecular (multiplex ligation-dependent probe amplification (MLPA)/next-generation sequencing (NGS) and Sanger methods) and in silico analyses were performed in order to identify alterations in DMD gene and protein in a patient with a clinical manifestation and with high creatine kinase levels. Herein, we described a previously unreported intronic variant in DMD and reduced dystrophin staining in the muscle biopsy. This novel DMD variant allele, c.9649+4A>T that was located in a splice donor site within intron 66. Sanger sequencing analysis from maternal DNA showed the presence of both variant c.9649+4A>T and wild-type (WT) DMD alleles. Different computational tools suggested that this nucleotide change might affect splicing through a WT donor site disruption, occurring in an evolutionarily conserved region. Indeed, we observed that this novel variant, could explain the reduced dystrophin protein levels and discontinuous sarcolemmal staining in muscle biopsy, which suggests that c.9649+4A>T allele may be re-classified as pathogenic in the future. Our data show that the c.9649+4A>T intronic sequence variant in the DMD gene may be associated with an IMD phenotype and our findings reinforce the importance of a more precise diagnosis combining muscle biopsy, molecular techniques and comprehensive in silico approaches in the clinical cases with negative results for conventional genetic analysis.
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Distrofina , Distrofia Muscular de Duchenne , Distrofina/genética , Testes Genéticos , Humanos , Íntrons/genética , Distrofia Muscular de Duchenne/genética , Mutação , FenótipoRESUMO
BACKGROUND: Anxiety and depressive symptoms are prevalent in patients with refractory mesial temporal lobe epilepsy related to hippocampal sclerosis (MTLE-HS) before and after anterior temporal lobectomy (ATL). AIMS: (1) To follow the levels of anxiety and depressive symptoms long-term after ATL among patients with refractory MTLE-HS; (2) To identify pre- and postsurgical variables associated with the levels of anxiety and depressive symptoms after surgery. METHODS: We compared the levels of anxiety and depressive symptoms determined by the Hospital Anxiety and Depression Scale (HADS) before and long after ATL (mean 104â¯months, range 70-130) in 41 consecutive patients refractory MTLE-HS. The last follow-up was between September 2018 and March 2020. We also determined pre- and postsurgical variables independently associated with the HADS scores after surgery. RESULTS: The scores of HADS and its subdomains related to anxiety and depression decreased significantly (pâ¯<â¯0.01) after ATL. After multiple linear regressions, the HADS-Anxiety scores before surgery (Bâ¯=â¯0.47, CI 95% 0.20 to 0.75, pâ¯=â¯0.001) and at follow-up after surgery (Bâ¯=â¯0.07, CI 0.00 to 0.14, pâ¯=â¯0.05) remain independently and positively associated with HADS-Anxiety scores after surgery. The HADS-Depression scores after surgery were independently positively associated with HADS-Depression scores before surgery (Bâ¯=â¯0.39, CI 95% 0.10 to 0.76, pâ¯=â¯0.01) and worse seizure control after surgery (Bâ¯=â¯1.55, CI 95% 0.23 to 2.87, pâ¯=â¯0.02). CONCLUSION: Anxiety and depressive symptoms in patients with MTLE-HS significantly improved after ATL. Presurgical levels of anxiety and depressive symptoms, respectively, were positively associated with the postsurgical levels of those symptoms. Length of follow-up is associated with anxiety, and worse seizure control is associated with depressive symptoms after ATL. The results have implications for the surgical management of MTLE-HS patients.