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BACKGROUND AND AIMS: Chronic stress associates with cardiovascular disease, but mechanisms remain incompletely defined. Advanced imaging was used to identify stress-related neural imaging phenotypes associated with atherosclerosis. METHODS: Twenty-seven individuals with post-traumatic stress disorder (PTSD), 45 trauma-exposed controls without PTSD, and 22 healthy controls underwent 18F-fluorodeoxyglucose positron emission tomography/magnetic resonance imaging (18F-FDG PET/MRI). Atherosclerotic inflammation and burden were assessed using 18F-FDG PET (as maximal target-to-background ratio, TBR max) and MRI, respectively. Inflammation was assessed using high-sensitivity C-reactive protein (hsCRP) and leucopoietic imaging (18F-FDG PET uptake in spleen and bone marrow). Stress-associated neural network activity (SNA) was assessed on 18F-FDG PET as amygdala relative to ventromedial prefrontal cortex (vmPFC) activity. MRI diffusion tensor imaging assessed the axonal integrity (AI) of the uncinate fasciculus (major white matter tract connecting vmPFC and amygdala). RESULTS: Median age was 37 years old and 54% of participants were female. There were no significant differences in atherosclerotic inflammation between participants with PTSD and controls; adjusted mean difference in TBR max (95% confidence interval) of the aorta 0.020 (-0.098, 0.138), and of the carotids 0.014 (-0.091, 0.119). Participants with PTSD had higher hsCRP, spleen activity, and aorta atherosclerotic burden (normalized wall index). Participants with PTSD also had higher SNA and lower AI. Across the cohort, carotid atherosclerotic burden (standard deviation of wall thickness) associated positively with SNA and negatively with AI independent of Framingham risk score. CONCLUSIONS: In this study of limited size, participants with PTSD did not have higher atherosclerotic inflammation than controls. Notably, impaired cortico-limbic interactions (higher amygdala relative to vmPFC activity or disruption of their intercommunication) associated with carotid atherosclerotic burden. Larger studies are needed to refine these findings.
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Enfermedades de las Arterias Carótidas , Tomografía de Emisión de Positrones , Trastornos por Estrés Postraumático , Humanos , Femenino , Masculino , Adulto , Trastornos por Estrés Postraumático/fisiopatología , Trastornos por Estrés Postraumático/diagnóstico por imagen , Enfermedades de las Arterias Carótidas/fisiopatología , Enfermedades de las Arterias Carótidas/diagnóstico por imagen , Fluorodesoxiglucosa F18 , Imagen por Resonancia Magnética , Persona de Mediana Edad , Corteza Prefrontal/diagnóstico por imagen , Corteza Prefrontal/fisiopatología , Amígdala del Cerebelo/diagnóstico por imagen , Amígdala del Cerebelo/fisiopatología , Radiofármacos , Estudios de Casos y Controles , Estrés Psicológico/fisiopatología , Estrés Psicológico/complicacionesRESUMEN
Purpose: We describe a method to identify repeatable liver computed tomography (CT) radiomic features, suitable for detection of steatosis, in nonhuman primates. Criteria used for feature selection exclude nonrepeatable features and may be useful to improve the performance and robustness of radiomics-based predictive models. Approach: Six crab-eating macaques were equally assigned to two experimental groups, fed regular chow or an atherogenic diet. High-resolution CT images were acquired over several days for each macaque. First-order and second-order radiomic features were extracted from six regions in the liver parenchyma, either with or without liver-to-spleen intensity normalization from images reconstructed using either a standard (B-filter) or a bone-enhanced (D-filter) kernel. Intrasubject repeatability of each feature was assessed using a paired t-test for all scans and the minimum p-value was identified for each macaque. Repeatable features were defined as having a minimum p-value among all macaques above the significance level after Bonferroni's correction. Features showing a significant difference with respect to diet group were identified using a two-sample t-test. Results: A list of repeatable features was generated for each type of image. The largest number of repeatable features was achieved from spleen-normalized D-filtered images, which also produced the largest number of second-order radiomic features that were repeatable and different between diet groups. Conclusions: Repeatability depends on reconstruction kernel and normalization. Features were quantified and ranked based on their repeatability. Features to be excluded for more robust models were identified. Features that were repeatable but different between diet groups were also identified.
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The current standard for measuring coronary artery calcification to determine the extent of atherosclerosis is by calculating the Agatston score from computed tomography (CT). However, the Agatston score disregards pixel values less than 130 Hounsfield Units (HU) and calcium regions less than 1 mm2. Due to this thresholding, the score is not sensitive to small, weakly attenuating regions of calcium deposition and may not detect nascent micro-calcification. A recently proposed metric called the spatially weighted calcium score (SWCS) also utilizes CT but does not include a threshold for HU and does not require elevated signals in contiguous pixels. Thus, the SWCS is sensitive to weakly attenuating, smaller calcium deposits and may improve the measurement of coronary heart disease risk. Currently, the SWCS is underutilized owing to the added computational complexity. To promote translation of the SWCS into clinical research and reliable, repeatable computation of the score, the aim of this study was to develop a semi-automatic graphical tool that calculates both the SWCS and the Agatston score. The program requires gated cardiac CT scans with a calcium hydroxyapatite phantom in the field of view. The phantom allows for deriving a weighting function, from which each pixel's weight is adjusted, allowing for the mitigation of signal variations and variability between scans. With all three anatomical views visible simultaneously, the user traces the course of the four main coronary arteries by placing points or regions of interest. Features such as scroll-to-zoom, double-click to delete, and brightness/contrast adjustment, along with written guidance at every step, make the program user-friendly and easy to use. Once tracing the arteries is complete, the program generates reports, which include the scores and snapshots of any visible calcium. The SWCS may reveal the presence of subclinical disease, which may be used for early intervention and lifestyle changes.
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Calcinosis , Enfermedad de la Arteria Coronaria , Humanos , Calcio , Vasos Coronarios/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Reproducibilidad de los Resultados , Angiografía Coronaria/métodosRESUMEN
BACKGROUND: The optimal treatment of intermediate-risk pulmonary embolism (PE) in hemodynamically stable patients remains unknown. Fibrinolytics reduce the risk of hemodynamic deterioration but increase bleeding risk. DS-1040, an inhibitor of thrombin-activatable fibrinolysis inhibitor, enhanced endogenous fibrinolytic activity without increasing bleeding risk in preclinical studies. OBJECTIVES: To evaluate the tolerability and explore the efficacy of DS-1040 in patients with acute PE. METHODS: In this multicenter, randomized, double-blind, placebo-controlled study, ascending doses of intravenous DS-1040 (20-80 mg) or placebo were added to enoxaparin (1 mg/kg twice daily) in patients with intermediate-risk PE. The primary endpoint was the number of patients with major or clinically relevant nonmajor bleeding. The percentage change in thrombus volume and right-to-left ventricular dimensions, assessed using quantitative computed tomography pulmonary angiography, at baseline and after 12 to 72 hours were used to explore the efficacy of DS-1040. RESULTS: Of 125 patients with all available data, 38 were randomized to placebo and 87 to DS-1040. The primary endpoint occurred in 1 patient in the placebo group (2.6%) and 4 patients who received DS-1040 (4.6%). One subject experienced major bleeding (DS-1040 80 mg group); no fatal or intracranial bleeding occurred. Thrombus volume was 25% to 45% lower after infusion, with no differences between the DS-1040 and placebo groups. There was no difference in the change from baseline right-to-left ventricular dimensions between the DS-1040 and placebo groups. CONCLUSION: In patients with acute PE, adding DS-1040 to standard anticoagulation was not associated with an increase in bleeding but did not improve thrombus resolution or right ventricular dilation.
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Carboxipeptidasa B2 , Embolia Pulmonar , Humanos , Fibrinolíticos/uso terapéutico , Embolia Pulmonar/complicaciones , Anticoagulantes/uso terapéutico , Terapia Trombolítica/efectos adversos , Hemorragia/tratamiento farmacológicoRESUMEN
Severe liver impairment is a well-known hallmark of Ebola virus disease (EVD). However, the role of hepatic involvement in EVD progression is understudied. Medical imaging in established animal models of EVD (e.g., nonhuman primates [NHPs]) can be a strong complement to traditional assays to better investigate this pathophysiological process in vivo and noninvasively. In this proof-of-concept study, we used longitudinal multiparametric magnetic resonance imaging (MRI) to characterize liver morphology and function in nine rhesus monkeys after exposure to Ebola virus (EBOV). Starting 5 days postexposure, MRI assessments of liver appearance, morphology, and size were consistently compatible with the presence of hepatic edema, inflammation, and congestion, leading to significant hepatomegaly at necropsy. MRI performed after injection of a hepatobiliary contrast agent demonstrated decreased liver signal on the day of euthanasia, suggesting progressive hepatocellular dysfunction and hepatic secretory impairment associated with EBOV infection. Importantly, MRI-assessed deterioration of biliary function was acute and progressed faster than changes in serum bilirubin concentrations. These findings suggest that longitudinal quantitative in vivo imaging may be a useful addition to standard biological assays to gain additional knowledge about organ pathophysiology in animal models of EVD. IMPORTANCE Severe liver impairment is a well-known hallmark of Ebola virus disease (EVD), but the contribution of hepatic pathophysiology to EVD progression is not fully understood. Noninvasive medical imaging of liver structure and function in well-established animal models of disease may shed light on this important aspect of EVD. In this proof-of-concept study, we used longitudinal magnetic resonance imaging (MRI) to characterize liver abnormalities and dysfunction in rhesus monkeys exposed to Ebola virus. The results indicate that in vivo MRI may be used as a noninvasive readout of organ pathophysiology in EVD and may be used in future animal studies to further characterize organ-specific damage of this condition, in addition to standard biological assays.
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Ebolavirus , Fiebre Hemorrágica Ebola , Hepatopatías , Animales , Macaca mulatta , Imagen por Resonancia Magnética , Modelos Animales de EnfermedadRESUMEN
Marburg virus (MARV) is a highly virulent zoonotic filovirid that causes Marburg virus disease (MVD) in humans. The pathogenesis of MVD remains poorly understood, partially due to the low number of cases that can be studied, the absence of state-of-the-art medical equipment in areas where cases are reported, and limitations on the number of animals that can be safely used in experimental studies under maximum containment animal biosafety level 4 conditions. Medical imaging modalities, such as whole-body computed tomography (CT), may help to describe disease progression in vivo, potentially replacing ethically contentious and logistically challenging serial euthanasia studies. Towards this vision, we performed a pilot study, during which we acquired whole-body CT images of 6 rhesus monkeys before and 7 to 9 days after intramuscular MARV exposure. We identified imaging abnormalities in the liver, spleen, and axillary lymph nodes that corresponded to clinical, virological, and gross pathological hallmarks of MVD in this animal model. Quantitative image analysis indicated hepatomegaly with a significant reduction in organ density (indicating fatty infiltration of the liver), splenomegaly, and edema that corresponded with gross pathological and histopathological findings. Our results indicated that CT imaging could be used to verify and quantify typical MVD pathogenesis versus altered, diminished, or absent disease severity or progression in the presence of candidate medical countermeasures, thus possibly reducing the number of animals needed and eliminating serial euthanasia. IMPORTANCE Marburg virus (MARV) is a highly virulent zoonotic filovirid that causes Marburg virus disease (MVD) in humans. Much is unknown about disease progression and, thus, prevention and treatment options are limited. Medical imaging modalities, such as whole-body computed tomography (CT), have the potential to improve understanding of MVD pathogenesis. Our study used CT to identify abnormalities in the liver, spleen, and axillary lymph nodes that corresponded to known clinical signs of MVD in this animal model. Our results indicated that CT imaging and analyses could be used to elucidate pathogenesis and possibly assess the efficacy of candidate treatments.
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Enfermedad del Virus de Marburg , Marburgvirus , Humanos , Animales , Enfermedad del Virus de Marburg/diagnóstico por imagen , Enfermedad del Virus de Marburg/patología , Proyectos Piloto , Tomografía Computarizada por Rayos X , Progresión de la Enfermedad , PrimatesRESUMEN
Rationale: There is upper airway inflammation in patients with obstructive sleep apnea (OSA), which reduces with continuous positive airway pressure (CPAP) therapy. Objectives: Validate the use of positron emission tomography (PET)/magnetic resonance imaging (MRI) to quantify metabolic activity within the pharyngeal mucosa of patients with OSA against nasal lavage proteomics and assess the impact of CPAP therapy. Methods: Adults with OSA underwent [18F]-Fluoro-2-deoxy-D-glucose PET/MRI of the neck before and 3 months after initiating CPAP. Nasal lavage samples were collected. Inflammatory protein expression from samples was analyzed using the Olink platform. Upper airway imaging segmentation was performed. Target-to-background ratio (TBRmax) was calculated from target pharyngeal maximum standard uptake values (SUV) and personalized background mean SUV. Most-diseased segment TBRmax was identified per participant at locations with the highest PET avidity. Correlation analysis was performed between baseline TBRmax and nasal lavage proteomics. TBRmax was compared before and after CPAP using linear mixed-effect models. Results: Among 38 participants, the baseline mean age was 46.3 years (standard deviation [SD], 12.5), 21% were female, the mean body mass index was 30.9 kg/m2 (SD, 4.6), and the mean respiratory disturbance index measured by peripheral arterial tonometry was 31 events/h (SD, 16.4). There was a significant positive correlation between pharyngeal mucosa most-diseased segment TBRmax and nasal lavage proteomic inflammation (r = 0.41 [P < 0.001, false discovery rate = 0.002]). Primary analysis revealed a reduction in the most-diseased segment TBRmax after a median of 2.91 months of CPAP therapy (-0.86 [standard error (SE) ± 0.30; P = 0.007]). Stratified analysis by smoking status revealed a significantly decreased most-diseased segment TBRmax after CPAP therapy among never-smokers but not among ever-smokers (-1.01 [SE ± 0.39; P = 0.015] vs. -0.64 [SE ± 0.49; P = 0.201]). Conclusions: CPAP therapy reduces metabolic activity measured by PET/MRI within the upper airway of adults with OSA. Furthermore, PET/MRI measures of upper airway metabolic activity correlate with a noninvasive marker of inflammation (i.e., nasal lavage inflammatory protein expression).
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Proteómica , Apnea Obstructiva del Sueño , Adulto , Humanos , Femenino , Persona de Mediana Edad , Masculino , Apnea Obstructiva del Sueño/diagnóstico por imagen , Apnea Obstructiva del Sueño/terapia , Presión de las Vías Aéreas Positiva Contínua/métodos , Imagen por Resonancia Magnética , Inflamación/diagnóstico por imagen , Tomografía de Emisión de PositronesRESUMEN
Healthcare is one of the most critical sectors due to its importance in handling public health. With the outbreak of various diseases, more recently during Covid-19, this sector has gained further attention. The pandemic has exposed vulnerabilities in the healthcare supply chain (HSC). Recent advancements like the adoption of various advanced technologies viz. AI and Industry 4.0 in the healthcare supply chain are turning out to be game-changers. This study focuses on identifying critical success factors (CSFs) for AI adoption in HSC in the emerging economy context. Rough SWARA is used for ranking CSFs of AI adoption in HSC. Results indicate that technological (TEC) factors are the most influential factor that impacts the adoption of AI in HSC in the context of emerging economies, followed by institutional or environmental (INT), human (HUM), and organizational (ORG) dimensions.
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PURPOSE: To further characterize the relationship between obstructive sleep apnea (OSA) and carotid atherosclerosis, we examined the structural and metabolic features of carotid plaque using hybrid 18-F-fluorodeoxyglucose (FDG) Positron Emission Tomography/Magnetic Resonance Imaging (PET/MRI) in the Multi-Ethnic Study of Atherosclerosis (MESA). METHODS: We studied 46 individuals from the MESA-PET and MESA-Sleep ancillary studies. OSA was defined as an apnea hypopnea index [AHI] ≥ 15 events per hour (4% desaturation). PET/MRI was used to measure carotid plaque inflammation (using target-to-background-ratios [TBR]) and carotid wall thickness (CWT). Linear regression was used to assess the associations between OSA, CWT and TBR. RESULTS: The mean age was 67.9 years (SD 8.53) and the mean BMI was 28.9 kg/m2 (SD 4.47). There was a trend toward a higher mean CWT in the OSA (n = 11) vs. non-OSA group (n = 35), 1.51 vs. 1.41 (p = 0.098). TBR did not differ by OSA groups, and there was no significant association between OSA and carotid plaque inflammation (TBR) in adjusted analyses. Although there was a significant interaction between OSA and obesity, there were no statistically significant associations between OSA and vascular inflammation in stratified analysis by obesity. CONCLUSION: Despite a trend toward a higher carotid wall thickness in OSA vs. non-OSA participants, we did not find an independent association between OSA and carotid plaque inflammation using PET/MRI in MESA. Our findings suggest that simultaneous assessments of structural and metabolic features of atherosclerosis may fill current knowledge gaps pertaining to the influence of OSA on atherosclerosis prevalence and progression.
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Aterosclerosis , Enfermedades de las Arterias Carótidas , Placa Aterosclerótica , Síndromes de la Apnea del Sueño , Apnea Obstructiva del Sueño , Humanos , Anciano , Valor Predictivo de las Pruebas , Obesidad , InflamaciónRESUMEN
OBJECTIVE: Recent large-scale randomised trials demonstrate that immunomodulators reduce cardiovascular (CV) events among the general population. However, it is uncertain whether these effects apply to rheumatoid arthritis (RA) and if certain treatment strategies in RA reduce CV risk to a greater extent. METHODS: Patients with active RA despite use of methotrexate were randomly assigned to addition of a tumour necrosis factor (TNF) inhibitor (TNFi) or addition of sulfasalazine and hydroxychloroquine (triple therapy) for 24 weeks. Baseline and follow-up 18F-fluorodeoxyglucose-positron emission tomography/CT scans were assessed for change in arterial inflammation, an index of CV risk, measured as an arterial target-to-background ratio (TBR) in the carotid arteries and aorta. RESULTS: 115 patients completed the protocol. The two treatment groups were well balanced with a median age of 58 years, 71% women, 57% seropositive and a baseline disease activity score in 28 joints of 4.8 (IQR 4.0, 5.6). Baseline TBR was similar across the two groups. Significant TBR reductions were observed in both groups-ΔTNFi: -0.24 (SD=0.51), Δtriple therapy: -0.19 (SD=0.51)-without difference between groups (difference in Δs: -0.02, 95% CI -0.19 to 0.15, p=0.79). While disease activity was significantly reduced across both treatment groups, there was no association with change in TBR (ß=0.04, 95% CI -0.03 to 0.10). CONCLUSION: We found that addition of either a TNFi or triple therapy resulted in clinically important improvements in vascular inflammation. However, the addition of a TNFi did not reduce arterial inflammation more than triple therapy. TRIAL REGISTRATION NUMBER: NCT02374021.
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Antirreumáticos , Arteritis , Artritis Reumatoide , Enfermedades Cardiovasculares , Humanos , Femenino , Persona de Mediana Edad , Masculino , Antirreumáticos/efectos adversos , Enfermedades Cardiovasculares/prevención & control , Enfermedades Cardiovasculares/inducido químicamente , Factor de Necrosis Tumoral alfa , Factores de Riesgo , Artritis Reumatoide/diagnóstico por imagen , Artritis Reumatoide/tratamiento farmacológico , Artritis Reumatoide/inducido químicamente , Metotrexato/uso terapéutico , Factores Inmunológicos/uso terapéutico , Factores de Riesgo de Enfermedad Cardiaca , Arteritis/inducido químicamente , Arteritis/tratamiento farmacológico , Resultado del TratamientoRESUMEN
Purpose: We propose a method to identify sensitive and reliable whole-lung radiomic features from computed tomography (CT) images in a nonhuman primate model of coronavirus disease 2019 (COVID-19). Criteria used for feature selection in this method may improve the performance and robustness of predictive models. Approach: Fourteen crab-eating macaques were assigned to two experimental groups and exposed to either severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) or a mock inoculum. High-resolution CT scans were acquired before exposure and on several post-exposure days. Lung volumes were segmented using a deep-learning methodology, and radiomic features were extracted from the original image. The reliability of each feature was assessed by the intraclass correlation coefficient (ICC) using the mock-exposed group data. The sensitivity of each feature was assessed using the virus-exposed group data by defining a factor R that estimates the excess of variation above the maximum normal variation computed in the mock-exposed group. R and ICC were used to rank features and identify non-sensitive and unstable features. Results: Out of 111 radiomic features, 43% had excellent reliability ( ICC > 0.90 ), and 55% had either good ( ICC > 0.75 ) or moderate ( ICC > 0.50 ) reliability. Nineteen features were not sensitive to the radiological manifestations of SARS-CoV-2 exposure. The sensitivity of features showed patterns that suggested a correlation with the radiological manifestations. Conclusions: Features were quantified and ranked based on their sensitivity and reliability. Features to be excluded to create more robust models were identified. Applicability to similar viral pneumonia studies is also possible.
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Non-invasive positron emission tomography (PET) of vascular inflammation and atherosclerotic plaque by identifying increased uptake of 18F-fluordeoxyglucose (18F-FDG) is a powerful tool for monitoring disease activity, progression, and its response to therapy. 18F-FDG PET/computed tomography (PET/CT) of the aorta and carotid arteries has become widely used to assess changes in inflammation in clinical trials. However, the recent advent of hybrid PET/magnetic resonance (PET/MR) scanners has advantages for vascular imaging due to the reduction in radiation exposure and improved soft tissue contrast of MR compared to CT. Important for research and clinical use is an understanding of the scan-rescan repeatability of the PET measurement. While this has been studied for PET/CT, no data is currently available for vascular PET/MR imaging. In this study, we determined the scan-rescan measurement repeatability of 18F-FDG PET/MR in the aorta and carotid arteries was less than 5%, comparable to similar findings for 18F-FDG PET/CT.
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Fluorodesoxiglucosa F18 , Tomografía Computarizada por Tomografía de Emisión de Positrones , Humanos , Inflamación/diagnóstico por imagen , Imagen por Resonancia Magnética , Tomografía de Emisión de Positrones/métodos , Radiofármacos , Tomografía Computarizada por Rayos X/métodosRESUMEN
PURPOSE: To develop a novel non-invasive technique to quantify upper airway inflammation using positron emission tomography/magnetic resonance imaging (PET/MRI) in patients with obstructive sleep apnea (OSA). METHODS: Patients with treatment naïve moderate-to-severe OSA underwent [18F]-fluoro-2-deoxy-D-glucose (FDG) PET/MRI. Three readers independently performed tracings of the pharyngeal soft tissue on MRI. Standardized uptake values (SUV) were generated from region of interest (ROI) tracings on corresponding PET images. Background SUV was measured from the sternocleidomastoid muscle. SUV and target-to-background (TBR) were compared across readers using intraclass correlation coefficient (ICC) analyses. SUV from individual image slices were compared between each reader using Bland-Altman plots and Pearson correlation coefficients. All tracings were repeated by one reader for assessment of intra-reader reliability. RESULTS: Five participants completed our imaging protocol and analysis. Median age, body mass index, and apnea-hypopnea index were 41 years (IQR 40.5-68.5), 32.7 kg/m2 (IQR 28.1-38.1), and 30.7 event per hour (IQR 19.5-48.1), respectively. The highest metabolic activity regions were consistently localized to palatine or lingual tonsil adjacent mucosa. Twenty-five ICC met criteria for excellent agreement. The remaining three were TBR measurements which met criteria for good agreement. Head-to-head comparisons revealed strong correlation between each reader. CONCLUSIONS: Our novel imaging technique demonstrated reliable quantification of upper airway FDG avidity. This technology has implications for future work exploring local airway inflammation in individuals with OSA and exposure to pollutants. It may also serve as an assessment tool for response to OSA therapies.
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Fluorodesoxiglucosa F18 , Apnea Obstructiva del Sueño , Adulto , Anciano , Humanos , Inflamación , Imagen por Resonancia Magnética , Persona de Mediana Edad , Tomografía de Emisión de Positrones , Reproducibilidad de los ResultadosRESUMEN
The procurement of food grains from farmers is one of the biggest challenges under the COVID-19 outbreak due to country-wise lockdowns. The present study aims to reconfigure the existing food grain supply chain network. The study advances the extant literature by proposing a novel mathematical model that considers the government guidelines issued to procure food grains from farmers under the COVID-19 situation. The model includes personal distancing, a key parameter relevant in the COVID-19 crisis, and has remained unaddressed in the existing literature. The proposed model is tested in India. The effect of different parameters like personal distancing cost, carbon emission cost, fixed cost, and transportation cost is also investigated under a given set of procurement centers. Finally, the procurement schedule for each procurement center is generated, which is especially useful for managing its activities and is also helpful to farmers to streamline the process. Results indicate that the proposed model is highly effective under pandemic emergencies like the current COVID-19 crisis. Policymakers and the government will find this model helpful in drafting relevant policies regarding food grain procurement under emergencies such as the COVID-19 outbreak. The distribution segment of the supply chain network is not part of the present research work. In future studies, this part could be then added to the whole of the procurement process, and both procurement and distribution can be assessed together again.
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Credit risk imposes itself as a significant barrier of agriculture 4.0 investments in the supply chain finance (SCF) especially for Small and Medium-sized Enterprises. Therefore, it is important for financial service providers (FSPs) to differentiate between low- and high-quality SMEs to accurately forecast the credit risk. This study proposes a novel hybrid ensemble machine learning approach to forecast the credit risk associated with SMEs' agriculture 4.0 investments in SCF. Two core approaches were used, i.e., Rotation Forest algorithm and Logit Boosting algorithm. Key variables influencing the credit risk of agriculture 4.0 investments in SMEs were identified and evaluated using data collected from 216 agricultural SMEs, 195 Leading Enterprises and 104 FSPs operating in African agriculture sector. Besides the classical measures of credit risk assessment without involving SCF, the findings indicate that current ratio, financial leverage, profit margin on sales and growth rate of the agricultural SME are the upmost important variables that SCF actors need to focus on, in order to accurately and optimistically forecast and alleviate credit risk. The output of our study provides useful guidelines for SMEs, as it highlights the conditions under which they would be seen as creditworthy by FSPs. On the other hand, this study encourages the wide application of SCF in financing agriculture 4.0 investments. Due to the model's performance, credit risk forecasting accuracy is improved, which results in future savings and credit risk mitigation in agriculture 4.0 investments of SMEs in SCF.
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PURPOSE: Visceral adipose tissue (VAT) is proinflammatory and is associated with cardiovascular (CV) disease. We investigated the relationship between obstructive sleep apnea (OSA) and visceral adipose tissue (VAT) metabolic activity in a pilot group of patients using positron-emission tomography/magnetic resonance imaging (PET/MRI) with 18F-fluorodeoxyglucose (FDG) tracer as a novel marker of adipose tissue inflammation. PATIENTS AND METHODS: We analyzed patients from an ongoing study, recruiting those with newly diagnosed, untreated OSA (Respiratory Disturbance Index [RDI] ≥ 5), using home sleep apnea testing (WatchPAT-200 Central-Plus). PET/MRI scans were acquired before continuous positive airway pressure (CPAP)-initiation, and after 3 months of CPAP therapy. Adipose tissue metabolic activity (18F-FDG-uptake) was measured using standardized uptake values (SUV) within the adipose tissue depots. The primary outcome was VAT SUVmean, and secondary outcomes included VAT volume, and subcutaneous adipose tissue (SAT) volume/SUVmean. Reproducibility and reliability of outcome measures were analyzed using intraclass correlation coefficients (ICC). Multivariable linear regression was used to evaluate the association between OSA and primary/secondary outcomes. RESULTS: Our analytical sample (n = 16) was 81% male (mean age 47 ± 15 years, mean BMI of 29.9 ± 4.8kg/m2). About 56% had moderate to severe OSA (mean RDI 23 ± 6 events/hour), and 50% were adherent to CPAP. We demonstrated excellent inter/intra-rater reliability and reproducibility for the primary and secondary outcomes. Patients with moderate-to-severe OSA had a higher VAT SUV mean compared to those with mild OSA (0.795 ± 0.154 vs 0.602 ± 0.19, p = 0.04). OSA severity was positively associated with VAT SUVmean (primary outcome), adjusted for age and BMI (B [SE] = 0.013 ± 0.005, p = 0.03). Change in VAT volume was inversely correlated with CPAP adherence in unadjusted analysis (B [SE] = -48.4 ± 18.7, p = 0.02). CONCLUSION: Derangements in VAT metabolic activity are implicated in adverse cardiometabolic outcomes and may be one of the key drivers of CV risk in OSA. Our results are hypothesis-generating, and suggest that VAT should be investigated in future studies using multi-modal imaging to understand its role as a potential mediator of adverse cardiometabolic risk in OSA.
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STUDY OBJECTIVES: Short sleep duration (SD) is associated with cardiovascular disease. We investigated the relationship between objective SD and subclinical atherosclerosis employing hybrid positron emission tomography/magnetic resonance imaging with 18F-FDG tracer in the MESA cohort. METHODS: We utilized data from Multi-Ethnic Study of Atherosclerosis-SLEEP and Multi-Ethnic Study of Atherosclerosis-PET ancillary studies. SD and sleep fragmentation index (SFI) were assessed using 7-day actigraphy. The primary and secondary outcomes were carotid inflammation, defined using target-to-background ratios, and measures of carotid wall remodeling (carotid wall thickness), summarized by SD category. Multivariable linear regression was performed to assess the association between SD and SFI with the primary/secondary outcomes, adjusting for several covariates including apnea-hypopnea index, and cardiovascular disease risk. RESULTS: Our analytical sample (n = 58) was 62% female (mean age 68 ± 8.4 years). Average SD was 5.1 ± 0.9 hours in the short SD group (≤ 6 h/night, 31%), and 7.1 ± 0.8 hours in the normal SD group (69%). Prevalence of pathologic vascular inflammation (maximal target-to-background ratio > 1.6) was higher in the short SD group (89% vs 53%, P = .01). Those with short SD had a higher maximal target-to-background ratio (1.77 vs 1.71), although this was not statistically significant (P = .39). Carotid wall thickness was positively associated with SFI even after adjusting for covariates (Beta [standard error] = 0.073 ± [0.032], P = .03). CONCLUSIONS: Prevalence of pathologic vascular inflammation was higher among those who slept ≤ 6 hours, and vascular inflammation was higher among those with a SD of ≤ 6 hours. Interestingly, SFI was positively associated with carotid wall thickness even after adjustment for covariates. Our results are hypothesis generating but suggest that both habitual SD and SFI should be investigated in future studies as potential risk factors for subclinical atherosclerosis. CITATION: Kundel V, Reid M, Fayad Z, et al. Sleep duration and vascular inflammation using hybrid positron emission tomography/magnetic resonance imaging: results from the Multi-Ethnic Study of Atherosclerosis. J Clin Sleep Med. 2021;17(10):2009-2018.
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Aterosclerosis , Anciano , Aterosclerosis/diagnóstico por imagen , Femenino , Fluorodesoxiglucosa F18 , Humanos , Inflamación/diagnóstico por imagen , Espectroscopía de Resonancia Magnética , Masculino , Persona de Mediana Edad , Tomografía de Emisión de Positrones , SueñoRESUMEN
STUDY OBJECTIVES: Evaluate the association between obstructive sleep apnea (OSA), coronary artery calcium (CAC) density, and cardiovascular events in the Multi-Ethnic Study of Atherosclerosis (MESA). METHODS: We analyzed 1,041 participants with nonzero CAC scores who had polysomnography and CAC density data from the fifth examination of the Multi-Ethnic Study of Atherosclerosis. OSA was defined as apnea-hypopnea index ≥ 15 events/h. Multivariable linear regression models were used to evaluate the independent association between OSA and CAC density. Additionally, we evaluated the impact of OSA on associations of CAC measures with incident cardiovascular disease events by testing for interaction in Cox proportional hazard regression models. RESULTS: Our analytical sample was 45% female with a mean age of 70.6 +/- 9 years. Of this sample, 36.7% (n = 383/1041) had OSA (apnea-hypopnea index ≥ 15 events/h). OSA was inversely and weakly associated with CAC density (ß = -0.09; 95% CI, -0.17 to -0.02; P = .014) and remained significantly associated after controlling for traditional cardiovascular risk factors (ß = -0.08; 95% CI, -0.16 to 0; P = .043). However, this inverse association was attenuated after controlling for body mass index (ß = -0.05; 95% CI, -0.13 to 0.02; P = .174). The mean follow-up period for cardiovascular disease events was 13.3 +/- 2.8 years. Additionally, exploratory analysis demonstrated that CAC density was independently and inversely associated with cardiovascular disease events only in the non-OSA subgroup (apnea-hypopnea index ≤ 15 events/h) (hazard ratio, 0.509; 95% CI, 0.323-0.801); P = .0035). CONCLUSIONS: OSA was associated with lower CAC density, but this association was attenuated by body mass index. Further, increased CAC density was associated with a reduced risk of cardiovascular disease events only in individuals within the non-OSA group in exploratory analysis. CITATION: Newman SB, Kundel V, Matsuzaki M, et al. Sleep apnea, coronary artery calcium density, and cardiovascular events: results from the Multi-Ethnic Study of Atherosclerosis. J Clin Sleep Med. 2021;17(10):2075-2083.
Asunto(s)
Aterosclerosis , Enfermedades Cardiovasculares , Enfermedad de la Arteria Coronaria , Apnea Obstructiva del Sueño , Anciano , Aterosclerosis/complicaciones , Aterosclerosis/epidemiología , Calcio , Enfermedades Cardiovasculares/epidemiología , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Enfermedad de la Arteria Coronaria/epidemiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Factores de Riesgo , Apnea Obstructiva del Sueño/complicaciones , Apnea Obstructiva del Sueño/epidemiologíaRESUMEN
Individuals with rheumatoid arthritis (RA) are at increased risk for atherosclerotic cardiovascular disease (ASCVD) events relative to the general population, potentially mediated by atherosclerotic plaques that are more inflamed and rupture prone. We sought to address whether RA immunomodulators reduce vascular inflammation, thereby reducing ASCVD risk, and whether such reduction depends on the type of immunomodulator. The TARGET (Treatments Against RA and Effect on 18-Fluorodeoxyglucose [18 F-FDG] Positron Emission Tomography [PET]/Computed Tomography [CT]) trial (NCT02374021) will enroll 150 patients with RA with active disease and an inadequate response to methotrexate. Participants will be randomized to add either a tumor necrosis factor (TNF) inhibitor (etanercept or adalimumab) or sulfasalazine and hydroxychloroquine to their background methotrexate. Participants will undergo full-body 18 F-FDG-labelled PET scanning at baseline and after 6 months. Efficacy and safety evaluations will occur every 6 weeks, with therapy modified in a treat-to-target approach. The primary outcome is the comparison of change in arterial inflammation in the wall of the aorta and carotid arteries between the randomized treatment groups, specifically, the change in the mean of the maximum target-to-background ratio of arterial 18 F-FDG uptake in the most diseased segment of either the aorta and carotid arteries. A secondary analysis will compare the effects of achieving low disease activity or remission with those of moderate to high disease activity on vascular inflammation. The TARGET trial will test, for the first time, whether RA treatments reduce arterial inflammation and whether such reduction differs according to treatment strategy with either TNF inhibitors or a combination of nonbiologic disease-modifying antirheumatic drugs.
RESUMEN
BACKGROUND AND AIMS: Electronic cigarette (EC) use is popular among youth, touted as a safer alternative to smoking and promoted as a tool to aid in smoking cessation. EC cardiovascular safety however is not well established. The aim of this study was to examine cardiovascular consequences of EC use by evaluating their effect on the entire atherosclerotic cascade in young adults using noninvasive combined positron emission tomography (PET)/magnetic resonance imaging (MR) and comparing EC use with age matched smokers of traditional cigarettes and nonsmoking controls. METHODS: Carotid PET/MR was applied to look at vascular inflammation (18-fluorodeoxyglucose (FDG)-PET) and plaque burden (multi-contrast MR of vessel wall) from 60 18-30 year-old subjects (20 electronic cigarette users, 20 traditional smokers and 20 nonsmokers). RESULTS: Groups were reasonably well balanced in terms of age, gender, demographics, cardiovascular risk and most biomarkers. There were no differences in vascular inflammation as measured by 18-FDG-PET target to background ratios (TBR) between EC users, traditional cigarette smokers and nonsmokers. However, measures of carotid plaque burden - wall area, normalized wall index, and wall thickness - measured from MR were significantly higher in both traditional smokers and EC users than in nonsmokers. CONCLUSIONS: Young adult EC users, smokers and nonsmokers in our study did not exhibit vascular inflammation as defined by 18-F-FDG-PET TBR max, but smokers and EC users had significantly more carotid plaque burden compared to matched nonsmokers. Results could indicate that vaping does not cause an increase in vascular inflammation as measured by FDG-PET.