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1.
Circulation ; 150(1): 7-18, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38808522

RESUMO

BACKGROUND: Current cardiovascular magnetic resonance sequences cannot discriminate between different myocardial extracellular space (ECSs), including collagen, noncollagen, and inflammation. We sought to investigate whether cardiovascular magnetic resonance radiomics analysis can distinguish between noncollagen and inflammation from collagen in dilated cardiomyopathy. METHODS: We identified data from 132 patients with dilated cardiomyopathy scheduled for an invasive septal biopsy who underwent cardiovascular magnetic resonance at 3 T. Cardiovascular magnetic resonance imaging protocol included native and postcontrast T1 mapping and late gadolinium enhancement (LGE). Radiomic features were computed from the midseptal myocardium, near the biopsy region, on native T1, extracellular volume (ECV) map, and LGE images. Principal component analysis was used to reduce the number of radiomic features to 5 principal radiomics. Moreover, a correlation analysis was conducted to identify radiomic features exhibiting a strong correlation (r>0.9) with the 5 principal radiomics. Biopsy samples were used to quantify ECS, myocardial fibrosis, and inflammation. RESULTS: Four histopathological phenotypes were identified: low collagen (n=20), noncollagenous ECS expansion (n=49), mild to moderate collagenous ECS expansion (n=42), and severe collagenous ECS expansion (n=21). Noncollagenous expansion was associated with the highest risk of myocardial inflammation (65%). Although native T1 and ECV provided high diagnostic performance in differentiating severe fibrosis (C statistic, 0.90 and 0.90, respectively), their performance in differentiating between noncollagen and mild to moderate collagenous expansion decreased (C statistic: 0.59 and 0.55, respectively). Integration of ECV principal radiomics provided better discrimination and reclassification between noncollagen and mild to moderate collagen (C statistic, 0.79; net reclassification index, 0.83 [95% CI, 0.45-1.22]; P<0.001). There was a similar trend in the addition of native T1 principal radiomics (C statistic, 0.75; net reclassification index, 0.93 [95% CI, 0.56-1.29]; P<0.001) and LGE principal radiomics (C statistic, 0.74; net reclassification index, 0.59 [95% CI, 0.19-0.98]; P=0.004). Five radiomic features per sequence were identified with correlation analysis. They showed a similar improvement in performance for differentiating between noncollagen and mild to moderate collagen (native T1, ECV, LGE C statistic, 0.75, 0.77, and 0.71, respectively). These improvements remained significant when confined to a single radiomic feature (native T1, ECV, LGE C statistic, 0.71, 0.70, and 0.64, respectively). CONCLUSIONS: Radiomic features extracted from native T1, ECV, and LGE provide incremental information that improves our capability to discriminate noncollagenous expansion from mild to moderate collagen and could be useful for detecting subtle chronic inflammation in patients with dilated cardiomyopathy.


Assuntos
Cardiomiopatia Dilatada , Matriz Extracelular , Humanos , Cardiomiopatia Dilatada/diagnóstico por imagem , Cardiomiopatia Dilatada/patologia , Matriz Extracelular/patologia , Matriz Extracelular/metabolismo , Feminino , Masculino , Pessoa de Meia-Idade , Adulto , Colágeno/metabolismo , Miocárdio/patologia , Idoso , Fibrose , Imageamento por Ressonância Magnética/métodos , Biópsia , Análise de Componente Principal , Radiômica
2.
Nature ; 571(7766): 565-569, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31316206

RESUMO

Parkinson's disease is a neurodegenerative disorder with motor symptoms linked to the loss of dopaminergic neurons in the substantia nigra compacta. Although the mechanisms that trigger the loss of dopaminergic neurons are unclear, mitochondrial dysfunction and inflammation are thought to have key roles1,2. An early-onset form of Parkinson's disease is associated with mutations in the PINK1 kinase and PRKN ubiquitin ligase genes3. PINK1 and Parkin (encoded by PRKN) are involved in the clearance of damaged mitochondria in cultured cells4, but recent evidence obtained using knockout and knockin mouse models have led to contradictory results regarding the contributions of PINK1 and Parkin to mitophagy in vivo5-8. It has previously been shown that PINK1 and Parkin have a key role in adaptive immunity by repressing presentation of mitochondrial antigens9, which suggests that autoimmune mechanisms participate in the aetiology of Parkinson's disease. Here we show that intestinal infection with Gram-negative bacteria in Pink1-/- mice engages mitochondrial antigen presentation and autoimmune mechanisms that elicit the establishment of cytotoxic mitochondria-specific CD8+ T cells in the periphery and in the brain. Notably, these mice show a sharp decrease in the density of dopaminergic axonal varicosities in the striatum and are affected by motor impairment that is reversed after treatment with L-DOPA. These data support the idea that PINK1 is a repressor of the immune system, and provide a pathophysiological model in which intestinal infection acts as a triggering event in Parkinson's disease, which highlights the relevance of the gut-brain axis in the disease10.


Assuntos
Infecções por Enterobacteriaceae/microbiologia , Infecções por Enterobacteriaceae/fisiopatologia , Intestinos/microbiologia , Doença de Parkinson/genética , Doença de Parkinson/microbiologia , Proteínas Quinases/deficiência , Proteínas Quinases/genética , Animais , Apresentação de Antígeno/imunologia , Autoantígenos/imunologia , Axônios/patologia , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/patologia , Citrobacter rodentium/imunologia , Citrobacter rodentium/patogenicidade , Modelos Animais de Doenças , Neurônios Dopaminérgicos/imunologia , Neurônios Dopaminérgicos/patologia , Infecções por Enterobacteriaceae/imunologia , Infecções por Enterobacteriaceae/patologia , Feminino , Intestinos/imunologia , Intestinos/patologia , Levodopa/uso terapêutico , Masculino , Camundongos , Mitocôndrias/imunologia , Mitocôndrias/patologia , Neostriado/imunologia , Neostriado/microbiologia , Neostriado/patologia , Neostriado/fisiopatologia , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/fisiopatologia , Proteínas Quinases/imunologia , Ubiquitina-Proteína Ligases/deficiência , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/imunologia
3.
J Magn Reson Imaging ; 59(1): 179-189, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37052580

RESUMO

BACKGROUND: In cardiac T1 mapping, a series of T1 -weighted (T1 w) images are collected and numerically fitted to a two or three-parameter model of the signal recovery to estimate voxel-wise T1 values. To reduce the scan time, one can collect fewer T1 w images, albeit at the cost of precision or/and accuracy. Recently, the feasibility of using a neural network instead of conventional two- or three-parameter fit modeling has been demonstrated. However, prior studies used data from a single vendor and field strength; therefore, the generalizability of the models has not been established. PURPOSE: To develop and evaluate an accelerated cardiac T1 mapping approach based on MyoMapNet, a convolution neural network T1 estimator that can be used across different vendors and field strengths by incorporating the relevant scanner information as additional inputs to the model. STUDY TYPE: Retrospective, multicenter. POPULATION: A total of 1423 patients with known or suspected cardiac disease (808 male, 57 ± 16 years), from three centers, two vendors (Siemens, Philips), and two field strengths (1.5 T, 3 T). The data were randomly split into 60% training, 20% validation, and 20% testing. FIELD STRENGTH/SEQUENCE: A 1.5 T and 3 T, Modified Look-Locker inversion recovery (MOLLI) for native and postcontrast T1 . ASSESSMENT: Scanner-independent MyoMapNet (SI-MyoMapNet) was developed by altering the deep learning (DL) architecture of MyoMapNet to incorporate scanner vendor and field strength as inputs. Epicardial and endocardial contours and blood pool (by manually drawing a large region of interest in the blood pool) of the left ventricle were manually delineated by three readers, with 2, 8, and 9 years of experience, and SI-MyoMapNet myocardial and blood pool T1 values (calculated from four T1 w images) were compared with conventional MOLLI T1 values (calculated from 8 to 11 T1 w images). STATISTICAL TESTS: Equivalency test with 95% confidence interval (CI), linear regression slope, Pearson correlation coefficient (r), Bland-Altman analysis. RESULTS: The proposed SI-MyoMapNet successfully created T1 maps. Native and postcontrast T1 values measured from SI-MyoMapNet were strongly correlated with MOLLI, despite using only four T1 w images, at both field-strengths and vendors (all r > 0.86). For native T1 , SI-MyoMapNet and MOLLI were in good agreement for myocardial and blood T1 values in institution 1 (myocardium: 5 msec, 95% CI [3, 8]; blood: -10 msec, 95%CI [-16, -4]), in institution 2 (myocardium: 6 msec, 95% CI [0, 11]; blood: 0 msec, [-18, 17]), and in institution 3 (myocardium: 7 msec, 95% CI [-8, 22]; blood: 8 msec, [-14, 30]). Similar results were observed for postcontrast T1 . DATA CONCLUSION: Inclusion of field strength and vendor as additional inputs to the DL architecture allows generalizability of MyoMapNet across different vendors or field strength. EVIDENCE LEVEL: 2. TECHNICAL EFFICACY: Stage 2.


Assuntos
Coração , Miocárdio , Humanos , Masculino , Estudos Retrospectivos , Coração/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Ventrículos do Coração , Reprodutibilidade dos Testes
4.
BMC Anesthesiol ; 24(1): 153, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38649826

RESUMO

BACKGROUND: Regional analgesia techniques are crucial for pain management after cervical spine surgeries. Anesthesiologists strive to select the most effective and least hazardous regional analgesia technique for the cervical region. Our hypothesis is that an intermediate cervical plexus (IC) block can provide adequate postoperative analgesia compared to a cervical erector spinae (ES) block in patients undergoing anterior cervical spine surgery. METHODS: In this double-blind prospective trial, 58 patients were randomly assigned into two equal groups prior to the administration of general anesthesia. Patients in the IC group (n = 29) underwent ultrasound-guided bilateral intermediate cervical plexus block with 15 ml of bupivacaine 0.25% administered to each side. The ES group (n = 29) underwent ultrasound-guided bilateral cervical erector spinae plane blocks with 15 ml of 0.25% bupivacaine administered to each side at the C6 level. The primary outcome was to record the time to the first call for rescue analgesia (nalbuphine), and the secondary outcomes were to measure the performance time, the onset of the sensory block, the intraoperative fentanyl consumption, postoperative pain intensity using VAS, the postoperative total nalbuphine consumption, and postoperative complications such as nausea, vomiting, hypotension, and bradycardia. RESULTS: The performance and onset of sensory block times were significantly shorter in the IC group compared to the ES group. The time to first call for nalbuphine was significantly shorter in the IC group (7.31 ± 1.34 h) compared to the ES group (11.10 ± 1.82 h). The mean postoperative VAS scores were comparable between the two groups at the measured time points, except at 8 h, where it was significantly higher in the IC group, and at 12 h, where it was significantly higher in the ES group. The total nalbuphine consumption was significantly higher in the IC group (33.1 ± 10.13 mg) compared to the ES group (22.76 ± 8.62 mg). CONCLUSIONS: For patients undergoing anterior cervical spine surgery, the intermediate cervical plexus block does not provide better postoperative regional analgesia compared to the cervical erector spinae block. Performance time and onset time were shorter in the IC group, whereas nalbuphine consumption was lower in the ES group. TRIAL REGISTRATION: The trial was registered at clinicaltrials.gov. (NCT05577559, and the date of registration: 13-10-2022).


Assuntos
Bloqueio do Plexo Cervical , Vértebras Cervicais , Dor Pós-Operatória , Ultrassonografia de Intervenção , Humanos , Feminino , Ultrassonografia de Intervenção/métodos , Método Duplo-Cego , Masculino , Dor Pós-Operatória/prevenção & controle , Dor Pós-Operatória/tratamento farmacológico , Pessoa de Meia-Idade , Estudos Prospectivos , Vértebras Cervicais/cirurgia , Bloqueio do Plexo Cervical/métodos , Adulto , Anestésicos Locais/administração & dosagem , Bupivacaína/administração & dosagem , Bloqueio Nervoso/métodos , Músculos Paraespinais/diagnóstico por imagem , Analgésicos Opioides/administração & dosagem , Nalbufina/administração & dosagem , Idoso
5.
J Cardiovasc Magn Reson ; 25(1): 56, 2023 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-37784153

RESUMO

BACKGROUND: Exercise cardiovascular magnetic resonance (Ex-CMR) myocardial tagging would enable quantification of myocardial deformation after exercise. However, current electrocardiogram (ECG)-segmented sequences are limited for Ex-CMR. METHODS: We developed a highly accelerated balanced steady-state free-precession real-time tagging technique for 3 T. A 12-fold acceleration was achieved using incoherent sixfold random Cartesian sampling, twofold truncated outer phase encoding, and a deep learning resolution enhancement model. The technique was tested in two prospective studies. In a rest study of 27 patients referred for clinical CMR and 19 healthy subjects, a set of ECG-segmented for comparison and two sets of real-time tagging images for repeatability assessment were collected in 2-chamber and short-axis views with spatiotemporal resolution 2.0 × 2.0 mm2 and 29 ms. In an Ex-CMR study of 26 patients with known or suspected cardiac disease and 23 healthy subjects, real-time images were collected before and after exercise. Deformation was quantified using measures of short-axis global circumferential strain (GCS). Two experienced CMR readers evaluated the image quality of all real-time data pooled from both studies using a 4-point Likert scale for tagline quality (1-excellent; 2-good; 3-moderate; 4-poor) and artifact level (1-none; 2-minimal; 3-moderate; 4-significant). Statistical evaluation included Pearson correlation coefficient (r), intraclass correlation coefficient (ICC), and coefficient of variation (CoV). RESULTS: In the rest study, deformation was successfully quantified in 90% of cases. There was a good correlation (r = 0.71) between ECG-segmented and real-time measures of GCS, and repeatability was good to excellent (ICC = 0.86 [0.71, 0.94]) with a CoV of 4.7%. In the Ex-CMR study, deformation was successfully quantified in 96% of subjects pre-exercise and 84% of subjects post-exercise. Short-axis and 2-chamber tagline quality were 1.6 ± 0.7 and 1.9 ± 0.8 at rest and 1.9 ± 0.7 and 2.5 ± 0.8 after exercise, respectively. Short-axis and 2-chamber artifact level was 1.2 ± 0.5 and 1.4 ± 0.7 at rest and 1.3 ± 0.6 and 1.5 ± 0.8 post-exercise, respectively. CONCLUSION: We developed a highly accelerated real-time tagging technique and demonstrated its potential for Ex-CMR quantification of myocardial deformation. Further studies are needed to assess the clinical utility of our technique.


Assuntos
Coração , Imagem Cinética por Ressonância Magnética , Humanos , Estudos Prospectivos , Imagem Cinética por Ressonância Magnética/métodos , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Espectroscopia de Ressonância Magnética , Função Ventricular Esquerda
6.
Endocr Regul ; 57(1): 99-105, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37183690

RESUMO

Objective. Chronic kidney disease (CKD), metabolic syndrome (MetS) and insulin resistance (IR) are the major health problems associated with the increasing risk of cardiovascular and cerebrovascular complications. Methods. This cross-sectional study included 209 CKD patients of stage (3-5) on conservative treatment to assess the usage of lipid accumulation product (LAP) and visceral adiposity index (VAI) to predict both MetS and IR in CKD patients. Results. In males, from the anthropometric measurements, LAP was the best predictor of MetS with 94.4% sensitivity and 77.8% specificity. VAI was the next one with 83.3% sensitivity and 69.4% specificity. The same results were obtained in females. The receiver operating characteristic (ROC) curve showed LAP as the best predictor of MetS with the highest 92.6% sensitivity and 60.6% specificity followed by VAI with 83.6% sensitivity and 83.6% specificity. In addition, LAP was a good predictor of IR with more than 70% sensitivity in both males and females. VAI as a predictor of IR showed 62.2% sensitivity in males and 69.9% in females. Conclusion. The present data indicate that both LAP and VAI can serve as predictors of MetS and IR in CKD patients, whereas LAP is the best anthropometric measure to predict MetS and LAP is more sensitive and specific than VAI in IR predicting in both males and females.


Assuntos
Adiposidade , Resistência à Insulina , Produto da Acumulação Lipídica , Síndrome Metabólica , Insuficiência Renal Crônica , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Antropometria , Doenças Cardiovasculares/complicações , Transtornos Cerebrovasculares/complicações , Estudos Transversais , Síndrome Metabólica/complicações , Síndrome Metabólica/diagnóstico , Insuficiência Renal Crônica/complicações , Curva ROC , Sensibilidade e Especificidade , Prognóstico
7.
Sensors (Basel) ; 23(7)2023 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-37050550

RESUMO

Over the past two decades, there has been a growing demand for generating digital surface models (DSMs) in real-time, particularly for aircraft landing in degraded visual environments. Challenging landing environments can hinder a pilot's ability to accurately navigate, see the ground, and avoid obstacles that may lead to equipment damage or loss of life. While many accurate and robust filtering algorithms for airborne laser scanning (ALS) data have been developed, they are typically computationally expensive. Moreover, these filtering algorithms require high execution times, making them unsuitable for real-time applications. This research aims to design and implement an efficient algorithm that can be used in real-time on limited-resource embedded processors without the need for a supercomputer. The proposed algorithm effectively identifies the best safe landing zone (SLZ) for an aircraft/helicopter based on processing 3D LiDAR point cloud data collected from a LiDAR mounted on the aircraft/helicopter. The algorithm was successfully implemented in C++ in real-time and validated using professional software for flight simulation. By comparing the results with maps, this research demonstrates the ability of the developed method to assist pilots in identifying the safest landing zone for helicopters.

8.
J Magn Reson Imaging ; 55(6): 1812-1825, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-34559435

RESUMO

BACKGROUND: Heart failure patients with preserved ejection fraction (HFpEF) are at increased risk of future hospitalization. Contrast agents are often contra-indicated in HFpEF patients due to the high prevalence of concomitant kidney disease. Therefore, the prognostic value of a noncontrast cardiac magnetic resonance imaging (MRI) for HF-hospitalization is important. PURPOSE: To develop and test an explainable machine learning (ML) model to investigate incremental value of noncontrast cardiac MRI for predicting HF-hospitalization. STUDY TYPE: Retrospective. POPULATION: A total of 203 HFpEF patients (mean, 64 ± 12 years, 48% women) referred for cardiac MRI were randomly split into training validation (143 patients, ~70%) and test sets (60 patients, ~30%). FIELD STRENGTH: A 1.5 T, balanced steady-state free precession (bSSFP) sequence. ASSESSMENT: Two ML models were built based on the tree boosting technique and the eXtreme Gradient Boosting model (XGBoost): 1) basic clinical ML model using clinical and echocardiographic data and 2) cardiac MRI-based ML model that included noncontrast cardiac MRI markers in addition to the basic model. The primary end point was defined as HF-hospitalization. STATISTICAL TESTS: ML tool was used for advanced statistics, and the Elastic Net method for feature selection. Area under the receiver operating characteristic (ROC) curve (AUC) was compared between models using DeLong's test. To gain insight into the ML model, the SHapley Additive exPlanations (SHAP) method was leveraged. A P-value <0.05 was considered statistically significant. RESULTS: During follow-up (mean, 50 ± 39 months), 85 patients (42%) reached the end point. The cardiac MRI-based ML model using the XGBoost algorithm provided a significantly superior prediction of HF-hospitalization (AUC: 0.81) compared to the basic model (AUC: 0.64). The SHAP analysis revealed left atrium (LA) and right atrium (RV) strains as top imaging markers contributing to its performance with cutoff values of 17.5% and -15%, respectively. DATA CONCLUSIONS: Using an ML model, RV and LA strains measured in noncontrast cardiac MRI provide incremental value in predicting future hospitalization in HFpEF. EVIDENCE LEVEL: 3 TECHNICAL EFFICACY: Stage 2.


Assuntos
Insuficiência Cardíaca , Feminino , Insuficiência Cardíaca/diagnóstico por imagem , Hospitalização , Humanos , Imageamento por Ressonância Magnética , Masculino , Prognóstico , Estudos Retrospectivos , Volume Sistólico , Função Ventricular Esquerda
9.
J Cardiovasc Magn Reson ; 24(1): 40, 2022 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-35761339

RESUMO

BACKGROUND: Myocardial scar burden quantified using late gadolinium enhancement (LGE) cardiovascular magnetic resonance (CMR), has important prognostic value in hypertrophic cardiomyopathy (HCM). However, nearly 50% of HCM patients have no scar but undergo repeated gadolinium-based CMR over their life span. We sought to develop an artificial intelligence (AI)-based screening model using radiomics and deep learning (DL) features extracted from balanced steady state free precession (bSSFP) cine sequences to identify HCM patients without scar. METHODS: We evaluated three AI-based screening models using bSSFP cine image features extracted by radiomics, DL, or combined DL-Radiomics. Images for 759 HCM patients (50 ± 16 years, 66% men) in a multi-center/vendor study were used to develop and test model performance. An external dataset of 100 HCM patients (53 ± 14 years, 70% men) was used to assess model generalizability. Model performance was evaluated using area-under-receiver-operating curve (AUC). RESULTS: The DL-Radiomics model demonstrated higher AUC compared to DL and Radiomics in the internal (0.83 vs 0.77, p = 0.006 and 0.78, p = 0.05; n = 159) and external (0.74 vs 0.64, p = 0.006 and 0.71, p = 0.27; n = 100) datasets. The DL-Radiomics model correctly identified 43% and 28% of patients without scar in the internal and external datasets compared to 42% and 16% by Radiomics model and 42% and 23% by DL model, respectively. CONCLUSIONS: A DL-Radiomics AI model using bSSFP cine images outperforms DL or Radiomics models alone as a scar screening tool prior to gadolinium administration. Despite its potential, the clinical utility of the model remains limited and further investigation is needed to improve the accuracy and generalizability.


Assuntos
Cardiomiopatia Hipertrófica , Aprendizado Profundo , Inteligência Artificial , Cardiomiopatia Hipertrófica/complicações , Cardiomiopatia Hipertrófica/diagnóstico por imagem , Cicatriz/diagnóstico por imagem , Cicatriz/etiologia , Cicatriz/patologia , Meios de Contraste , Feminino , Gadolínio , Humanos , Imagem Cinética por Ressonância Magnética/métodos , Masculino , Valor Preditivo dos Testes
10.
Pediatr Transplant ; 26(1): e14178, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34687584

RESUMO

BACKGROUND: Literature supports equivalent kidney transplant outcomes in adults with systemic lupus erythematosus (SLE) compared with those without SLE. However, there are conflicting and scant data on kidney transplant outcomes, as well as controversy over optimal timing of transplantation, in children and adolescents with SLE. METHODS: Analysis included kidney-only transplant recipients aged 2-21 years from 2000 to 2017 enrolled in the Organ Procurement and Transplant Network (OPTN). The relationship between diagnosis (SLE n = 457, non-SLE glomerular disease n = 4492, and non-SLE non-glomerular disease n = 5605) and transplant outcomes was evaluated. The association between dialysis time and outcomes was analyzed in the SLE group only. RESULTS: In adjusted models, SLE had higher mortality compared with non-SLE glomerular recipients (HR 1.24 CI 1.07-1.44) and non-glomerular recipients (HR 1.42 CI 1.20-1.70). SLE was associated with higher graft failure compared with non-SLE glomerular (HR 1.42 CI 1.20-1.69) and non-glomerular disease (HR 1.67 CI 1.22-2.28). SLE had a higher risk of acute rejection at 1 year compared with non-glomerular disease (HR 1.39 CI 1.03-1.88). There was a decreased risk of delayed graft function compared with non-SLE glomerular disease (HR 0.54, CI 0.36-0.82). There were no significant associations between dialysis time and transplant outcomes in the SLE group. CONCLUSION: SLE in children and adolescents is associated with worse patient and graft survival compared with non-SLE diagnoses. Outcomes in children and adolescents with SLE are not associated with dialysis time. Further studies are needed to assess implications of potential earlier transplantation and shorter time on dialysis prior to transplantation.


Assuntos
Falência Renal Crônica/cirurgia , Transplante de Rim , Lúpus Eritematoso Sistêmico/complicações , Adolescente , Estudos de Casos e Controles , Criança , Pré-Escolar , Bases de Dados Factuais , Função Retardada do Enxerto/epidemiologia , Função Retardada do Enxerto/etiologia , Feminino , Rejeição de Enxerto/epidemiologia , Rejeição de Enxerto/etiologia , Sobrevivência de Enxerto , Humanos , Falência Renal Crônica/etiologia , Falência Renal Crônica/mortalidade , Modelos Logísticos , Masculino , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
11.
Am J Transplant ; 21(7): 2522-2531, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33443778

RESUMO

We compared the outcome of COVID-19 in immunosuppressed solid organ transplant (SOT) patients to a transplant naïve population. In total, 10 356 adult hospital admissions for COVID-19 from March 1, 2020 to April 27, 2020 were analyzed. Data were collected on demographics, baseline clinical conditions, medications, immunosuppression, and COVID-19 course. Primary outcome was combined death or mechanical ventilation. We assessed the association between primary outcome and prognostic variables using bivariate and multivariate regression models. We also compared the primary endpoint in SOT patients to an age, gender, and comorbidity-matched control group. Bivariate analysis found transplant status, age, gender, race/ethnicity, body mass index, diabetes, hypertension, cardiovascular disease, COPD, and GFR <60 mL/min/1.73 m2 to be significant predictors of combined death or mechanical ventilation. After multivariate logistic regression analysis, SOT status had a trend toward significance (odds ratio [OR] 1.29; 95% CI 0.99-1.69, p = .06). Compared to an age, gender, and comorbidity-matched control group, SOT patients had a higher combined risk of death or mechanical ventilation (OR 1.34; 95% CI 1.03-1.74, p = .027).


Assuntos
COVID-19 , Transplante de Órgãos , Adulto , Humanos , Terapia de Imunossupressão , SARS-CoV-2 , Transplantados
12.
Magn Reson Med ; 85(3): 1195-1208, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32924188

RESUMO

PURPOSE: Cardiac MR cine imaging allows accurate and reproducible assessment of cardiac function. However, its long scan time not only limits the spatial and temporal resolutions but is challenging in patients with breath-holding difficulty or non-sinus rhythms. To reduce scan time, we propose a multi-domain convolutional neural network (MD-CNN) for fast reconstruction of highly undersampled radial cine images. METHODS: MD-CNN is a complex-valued network that processes MR data in k-space and image domains via k-space interpolation and image-domain subnetworks for residual artifact suppression. MD-CNN exploits spatio-temporal correlations across timeframes and multi-coil redundancies to enable high acceleration. Radial cine data were prospectively collected in 108 subjects (50 ± 17 y, 72 males) using retrospective-gated acquisition with 80%:20% split for training/testing. Images were reconstructed by MD-CNN and k-t Radial Sparse-Sense(kt-RASPS) using an undersampled dataset (14 of 196 acquired views; relative acceleration rate = 14). MD-CNN images were evaluated quantitatively using mean-squared-error (MSE) and structural similarity index (SSIM) relative to reference images, and qualitatively by three independent readers for left ventricular (LV) border sharpness and temporal fidelity using 5-point Likert-scale (1-non-diagnostic, 2-poor, 3-fair, 4-good, and 5-excellent). RESULTS: MD-CNN showed improved MSE and SSIM compared to kt-RASPS (0.11 ± 0.10 vs. 0.61 ± 0.51, and 0.87 ± 0.07 vs. 0.72 ± 0.07, respectively; P < .01). Qualitatively, MD-CCN significantly outperformed kt-RASPS in LV border sharpness (3.87 ± 0.66 vs. 2.71 ± 0.58 at end-diastole, and 3.57 ± 0.6 vs. 2.56 ± 0.6 at end-systole, respectively; P < .01) and temporal fidelity (3.27 ± 0.65 vs. 2.59 ± 0.59; P < .01). CONCLUSION: MD-CNN reduces the scan time of cine imaging by a factor of 23.3 and provides superior image quality compared to kt-RASPS.


Assuntos
Aprendizado Profundo , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Imagem Cinética por Ressonância Magnética , Masculino , Redes Neurais de Computação , Estudos Retrospectivos
13.
J Magn Reson Imaging ; 54(1): 303-312, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33599043

RESUMO

BACKGROUND: Quantification of myocardium scarring in late gadolinium enhanced (LGE) cardiac magnetic resonance imaging can be challenging due to low scar-to-background contrast and low image quality. To resolve ambiguous LGE regions, experienced readers often use conventional cine sequences to accurately identify the myocardium borders. PURPOSE: To develop a deep learning model for combining LGE and cine images to improve the robustness and accuracy of LGE scar quantification. STUDY TYPE: Retrospective. POPULATION: A total of 191 hypertrophic cardiomyopathy patients: 1) 162 patients from two sites randomly split into training (50%; 81 patients), validation (25%, 40 patients), and testing (25%; 41 patients); and 2) an external testing dataset (29 patients) from a third site. FIELD STRENGTH/SEQUENCE: 1.5T, inversion-recovery segmented gradient-echo LGE and balanced steady-state free-precession cine sequences ASSESSMENT: Two convolutional neural networks (CNN) were trained for myocardium and scar segmentation, one with and one without LGE-Cine fusion. For CNN with fusion, the input was two aligned LGE and cine images at matched cardiac phase and anatomical location. For CNN without fusion, only LGE images were used as input. Manual segmentation of the datasets was used as reference standard. STATISTICAL TESTS: Manual and CNN-based quantifications of LGE scar burden and of myocardial volume were assessed using Pearson linear correlation coefficients (r) and Bland-Altman analysis. RESULTS: Both CNN models showed strong agreement with manual quantification of LGE scar burden and myocardium volume. CNN with LGE-Cine fusion was more robust than CNN without LGE-Cine fusion, allowing for successful segmentation of significantly more slices (603 [95%] vs. 562 (89%) of 635 slices; P < 0.001). Also, CNN with LGE-Cine fusion showed better agreement with manual quantification of LGE scar burden than CNN without LGE-Cine fusion (%ScarLGE-cine = 0.82 × %Scarmanual , r = 0.84 vs. %ScarLGE = 0.47 × %Scarmanual , r = 0.81) and myocardium volume (VolumeLGE-cine = 1.03 × Volumemanual , r = 0.96 vs. VolumeLGE = 0.91 × Volumemanual , r = 0.91). DATA CONCLUSION: CNN based LGE-Cine fusion can improve the robustness and accuracy of automated scar quantification. LEVEL OF EVIDENCE: 3 TECHNICAL EFFICACY: 1.


Assuntos
Aprendizado Profundo , Gadolínio , Cicatriz/diagnóstico por imagem , Cicatriz/patologia , Meios de Contraste , Humanos , Aumento da Imagem , Imageamento por Ressonância Magnética , Imagem Cinética por Ressonância Magnética , Miocárdio/patologia , Estudos Retrospectivos
14.
Transpl Infect Dis ; 23(3): e13540, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33259125

RESUMO

BACKGROUND: Several studies have shown that transplanting a hepatitis C virus (HCV)-negative recipients with a HCV-positive donor is feasible in a research setting. In February 2018, we began transplanting HCV-negative recipients with HCV-positive donors as standard of care. METHODS: All patients, except those with previously cured HCV and those with cirrhosis, were consented for HCV NAT-positive donor kidneys. After transplantation, patients were tested for HCV RNA until viremic. A direct-acting antiviral (DAA) agent was prescribed based on genotype and insurance approval. Sustained virologic response (SVR) at weeks 4 and 12 was recorded. Renal function and death censored graft survival at 1 year were evaluated and compared to recipients of HCV NAT-negative kidneys. RESULTS: A total of 25 HCV NAT-positive donor kidney transplants from February to October 2018 were performed. All patients received basiliximab and maintained with tacrolimus, mycophenolate mofetil, and prednisone. Median time from viremia to start of DAA was 13 (8-22) days. The most common genotype was 1a (60%), followed by 3a (28%). The most commonly prescribed DAA was ledipasvir/sofosbuvir (56%), followed by velpatasvir/sofosbuvir (32%), and then glecaprevir/pibrentasvir (12%). All patients achieved initial SVR12, except one. One patient had a mixed-genotype infection requiring retreatment to achieve SVR12. Death censored graft survival was 96%. Recipients of HCV NAT-positive organs compared to HCV NAT-negative organs received younger donors (mean 35 ± 8.9 vs 45.1 ± 15.7 years; P < .01) and spent less time on the waitlist (median 479 (93-582) vs 1808 (567-2263) days; P = .02). CONCLUSION: HCV NAT-negative recipients can be safely and successfully transplanted with HCV NAT-positive donor kidneys outside of a research protocol. Access to DAA and timely administration of therapy is important and an insurance approval process within the transplant center can be beneficial to patients. A case of mixed-genotype infection was presented, and although not as common, can be successfully treated. HCV organs can expand the organ pool and should no longer be considered experimental. The use of these organs in HCV-negative recipient's decreases waiting time, have excellent outcomes, and should be considered standard of care.


Assuntos
Hepatite C , Transplante de Rim , Antivirais/uso terapêutico , Hepacivirus , Hepatite C/tratamento farmacológico , Humanos , Doadores de Tecidos
15.
Pediatr Transplant ; 25(4): e14018, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33813782

RESUMO

BACKGROUND: The clinical course of SARS-CoV-2 in the pediatric kidney transplant population is not well described. METHODS: We performed a retrospective cohort study of a pediatric kidney transplant population at a New York transplant center. Baseline characteristics and clinical course of patients with SARS-CoV-2 positivity (Ab or PCR) were described, and comparison between COVID-positive and COVID-negative transplant patients was performed. RESULTS: Twenty-two patients had COVID-19 IgG testing performed, eight of whom also had PCR testing. 23% of our cohort had evidence of COVID-19 infection. Four patients had positive IgG only, and one patient had a positive PCR. All five patients with a positive COVID test were female. Two patients had COVID-19 symptoms, which were mild. Of the symptomatic patients, one had a positive PCR at time of symptoms, while the other had a negative PCR during symptoms but subsequently had positive IgG. As compared to patients with COVID-19 negative results, those with COVID-19 positivity were significantly more likely to have a known COVID-19 exposure, and were also more likely to be female. There was no significant difference in time from transplant between the groups. Those in the COVID-positive group had higher baseline antimetabolite dose and CNI troughs, although these did not reach statistical significance. CONCLUSIONS: Pediatric kidney transplant recipients are at risk for development of COVID-19 infection. While this population may be more at risk for SARS-CoV-2 infection due to their immunosuppressed status, their clinical course appears mild and similar to a healthy pediatric population.


Assuntos
COVID-19/epidemiologia , Transplante de Rim , Complicações Pós-Operatórias/epidemiologia , Adolescente , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Humanos , Estudos Retrospectivos , Adulto Jovem
16.
Pharmacology ; 106(7-8): 409-417, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34082428

RESUMO

INTRODUCTION: Pioglitazone is a thiazolidinedione oral antidiabetic agent. This study aimed to investigate the effects of pioglitazone as insulin sensitizer on ß-arrestin2 signaling in classical insulin target tissues. METHODS: Experiments involved three groups of mice; the first one involved mice fed standard chow diet for 16 weeks; the second one involved mice fed high-fructose, high-fat diet (HFrHFD) for 16 weeks; and the third one involved mice fed HFrHFD for 16 weeks and received pioglitazone (30 mg/kg/day, orally) in the last four weeks of feeding HFrHFD. RESULTS: The results showed significant improvement in the insulin sensitivity of pioglitazone-treated mice as manifested by significant reduction in the insulin resistance index. This improvement in insulin sensitivity was associated with significant increases in the ß-arrestin2 levels in the adipose tissue, liver, and skeletal muscle. Moreover, pioglitazone significantly increased ß-arrestin2 signaling in all the examined tissues as estimated from significant increases in phosphatidylinositol 4,5 bisphosphate and phosphorylation of Akt at serine 473 and significant decrease in diacylglycerol level. CONCLUSION: To the best of our knowledge, our work reports a new mechanism of action for pioglitazone through which it can enhance the insulin sensitivity. Pioglitazone increases ß-arrestin2 signaling in the adipose tissue, liver, and skeletal muscle of HFrHFD-fed mice.


Assuntos
Resistência à Insulina , Insulina/metabolismo , Pioglitazona/farmacologia , beta-Arrestina 2/metabolismo , Tecido Adiposo/efeitos dos fármacos , Tecido Adiposo/metabolismo , Animais , Dieta Hiperlipídica , Modelos Animais de Doenças , Frutose , Hipoglicemiantes/farmacologia , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Camundongos , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/metabolismo , Transdução de Sinais/efeitos dos fármacos
17.
Postgrad Med J ; 97(1152): 667-671, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33246966

RESUMO

The genesis of ketone bodies by organisms is a protective mechanism. This metabolic process helps organisms to survive acute metabolic derangements in times of nutrient deficiency. When prolonged, ketogenesis leads to ketoacidosis, which is a potentially life-threatening metabolic disorder due to the accumulation of keto-acids in the body. The most common cause is diabetic ketoacidosis, though starvation ketoacidosis and alcoholic ketoacidosis are not uncommon. The presentation of all ketoacidotic states is similar-being generally unwell, abdominal pain, rapid and shallow breathing, vomiting and dehydration. Non-diabetic ketoacidotic states are very commonly overlooked due to relative unawareness among the clinicians, leading to misdiagnosis and thereby inappropriate management culminating in added mortality and morbidity. We describe here six cases of alcoholic and starvation ketoacidosis, review the literature currently available and discuss the common pitfalls in managing such cases.


Assuntos
Dor Abdominal/etiologia , Cetoacidose Diabética/complicações , Cetoacidose Diabética/diagnóstico , Cetoácidos/metabolismo , Adolescente , Adulto , Idoso , Feminino , Humanos , Cetose/diagnóstico , Cetose/etiologia , Masculino , Pessoa de Meia-Idade
18.
J Environ Manage ; 281: 111881, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33401121

RESUMO

We need to produce higher foods even under declining natural resources to feed the projected population of 9 billion by 2050 and to sustain food security and nutrition. Abiotic stress has adversely affected canola crop and oil quality especially in sandy soils. To combat this stress, adaptation at the farm level using new and cost-effective amendments are required. Field trials were conducted in two different climatic zones to determine the efficacy of cane molasses, bagasse ash, sugar beet factory lime, and their compost mixtures to improve soil quality and heat stress-adapting canola. The results showed a significant improvement in bulk density, hydraulic conductivity, organic matter content, and available macronutrients of sandy soil and subsequent canola growth, yield, quality and water productivity due to the application of the tested soil amendments, particularly those mixed with compost. Despite the estimated reduction of yield by 18.5% due to heat stress, application of sugar beet lime and compost mixture not only compensated for this reduction but also increased the seed yield by 27.0%. These findings highlight the value of recycling compost-based sugar crop disposal as a cost-effective technology to boost crop tolerance to abiotic stress, ensuring sustainable agriculture and food security in arid environments.


Assuntos
Brassica napus , Poluentes do Solo , Agricultura , Solo , Poluentes do Solo/análise , Estresse Fisiológico , Açúcares
19.
J Environ Manage ; 277: 111388, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33002812

RESUMO

Land degradation due to soil salinity and sodicity is a serious concern in arid ecosystems. Despite the importance of conservation tillage in carbon sequestration and improving soil properties, its effect on saline-sodic soils under amendment application remains unknown. Therefore, the present study aimed to explore the combined effects of inorganic (sulfuric acid and gypsum) and organic (vermicompost) soil amendments and tillage systems (zero, reduced and deep tillage) on saline-sodic soil properties and wheat productivity. Deep tillage with vermicompost application significantly improved soil physical and chemical properties compared with control. Interestingly, integration between deep tillage and vermicompost decreased soil salinity and sodicity by 37% and 34%, respectively, compared with zero tillage and unamended soils. The application of vermicompost surpassed chemical amendments in the improvement of saline-sodic soils and consequently increased the growth and yield of wheat, provided that deep tillage was used as a suitable tillage system. Although deep tillage reduced soil organic carbon, application of vermicompost not only compensated this reduction, but also significantly increased soil organic carbon. This confirms the potential of combined deep tillage and vermicompost as a method for environmentally reclaiming saline-sodic soils.


Assuntos
Solo , Triticum , Agricultura , Carbono , Sequestro de Carbono , Ecossistema
20.
Environ Geochem Health ; 43(6): 2423-2431, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32926286

RESUMO

Although nickel (Ni) has direct relationship with nitrogen metabolism of plants, the high dose of Ni fertilizer in broad bean plants may affect the nitrogen use efficiency (NUE), impair plant development and even cause Ni pollution in soil. Thus, a pot experiment was set up to study the effect of urea fertilization on N-uptake, root and shoots' Ni content as well as growth of broad bean plants under different levels of Ni, using 15N tracer technique. 15N-labeled urea (5% 15N atom excess) was added at three doses (0, 30 and 60 mg N kg-1 soil). Nickel sulfate (NiSO4) was also applied at three levels (0, 50 and 100 mg Ni kg-1 soil). The experiment was laid out with or without acetic acid in randomized complete block design in three replicates. Treatment with the addition of 60 mg N + 50 mg Ni showed the highest values in dry weights of root and shoots, N-uptake by shoots, nitrogen derived from fertilizer (Ndff %) and NUE % by shoots in both with or without acetic acid solution. Higher rate of Ni addition can decrease shoot and root biomass by inhibiting the ability of the plant to uptake the nitrogen efficiently. However, addition of acetic acid solution induced the improvement of NUE % and Ndff % by shoot and root of broad bean plants. This study provides insight into how to improve plant yield without damaging the soil health and will be helpful to create a better world with sustainable agriculture.


Assuntos
Agricultura/métodos , Fertilizantes , Ureia/farmacologia , Vicia faba/efeitos dos fármacos , Vicia faba/crescimento & desenvolvimento , Ácido Acético/farmacologia , Biomassa , Níquel/farmacocinética , Níquel/farmacologia , Nitrogênio/análise , Nitrogênio/farmacocinética , Isótopos de Nitrogênio/análise , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/crescimento & desenvolvimento , Brotos de Planta/efeitos dos fármacos , Brotos de Planta/crescimento & desenvolvimento
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