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1.
Eur Heart J Suppl ; 26(Suppl 1): i23-i28, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38867874

RESUMO

The identification of ventricular premature complexes during a cardiological evaluation necessitates the implementation of diagnostic processes aimed at discerning the clinical context that may predispose individuals to a high risk of sudden cardiac death. Epidemiological studies reveal that ventricular premature beats occur in approximately 75% of healthy (or seemingly healthy) individuals, as long as there is no evidence of underlying structural heart disease, such as benign idiopathic ventricular extrasystole originating from the right and left ventricular outflow tracts. In the real world, however, ventricular ectopic beats with morphologies very similar to seemingly benign occurrences are not uncommon. They are notable in subjects exhibiting rapid and complex repetitive forms during exercise testing and Holter electrocardiogram. Additionally, these subjects may display more or less extensive scarring signs on cardiac magnetic resonance and may have a family history of cardiomyopathy and/or sudden cardiac death. Therefore, the purpose of this review is to critically analyse the process of evaluating premature ventricular complexes, which is crucial for accurate risk stratification. The latter cannot overlook some inevitable elements, including morphology, origin, complexity, and the associated clinical setting (absence or presence of structural heart disease).

2.
J Cardiovasc Magn Reson ; 26(2): 101047, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38825155

RESUMO

BACKGROUND: Coronary artery wall contrast enhancement (CE) has been applied to non-invasive visualization of changes to the coronary artery wall in systemic lupus erythematosus (SLE). This study investigated the feasibility of quantifying CE to detect coronary involvement in IgG4-related disease (IgG4-RD), as well as the influence on disease activity assessment. METHODS: A total of 93 subjects (31 IgG4-RD; 29 SLE; 33 controls) were recruited in the study. Coronary artery wall imaging was performed in a 3.0 T MRI scanner. Serological markers and IgG4-RD Responder Index (IgG4-RD-RI) scores were collected for correlation analysis. RESULTS: Coronary wall CE was observed in 29 (94 %) IgG4-RD patients and 22 (76 %) SLE patients. Contrast-to-noise ratio (CNR) and total CE area were significantly higher in patient groups compared to controls (CNR: 6.1 ± 2.7 [IgG4-RD] v. 4.2 ± 2.3 [SLE] v. 1.9 ± 1.5 [control], P < 0.001; Total CE area: 3.0 [3.0-6.6] v. 1.7 [1.5-2.6] v. 0.3 [0.3-0.9], P < 0.001). In the IgG4-RD group, CNR and total CE area were correlated with the RI (CNR: r = 0.55, P = 0.002; total CE area: r = 0.39, P = 0.031). RI´ scored considering coronary involvement by CE, differed significantly from RI scored without consideration of CE (RI v. RI´: 15 ± 6 v. 16 ± 6, P < 0.001). CONCLUSIONS: Visualization and quantification of CMR coronary CE by CNR and total CE area could be utilized to detect subclinical and clinical coronary wall involvement, which is prevalent in IgG4-RD. The potential inclusion of small and medium-sized vessel involvements in the assessment of disease activity in IgG4-RD is worthy of further investigation.

3.
Indian J Radiol Imaging ; 34(3): 460-468, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38912243

RESUMO

Background and Aim Contrast-enhanced ultrasound (CEUS) can reliably identify vulnerable plaques. As atherosclerosis is a systemic disease, we evaluated whether contrast enhancement of carotid plaque (CECP) can predict severe coronary artery disease (CAD) by comparing CECP in patients who have had acute coronary syndromes (ACS) recently with asymptomatic individuals. Settings and Design This case-control study was done at a tertiary care center during 2022. Materials and Methods Fourteen participants were recruited in each group, after screening in-patients for carotid plaques and inclusion and exclusion criteria. Those who had history of ACS were enrolled as cases, while those who did not were enrolled as controls. All these patients underwent grayscale, Doppler, and CEUS examination for characterization of the carotid plaque. For cases, findings on CEUS were also compared with the severity of CAD on catheter coronary angiography. Statistical Analysis Diagnostic parameters including sensitivity, specificity, and diagnostic accuracy were calculated and proportions were compared by using Fisher's exact test. Results Eight out of 28 patients showed CECP. CECP and CAD were positively associated with p -Value of 0.033. Eighty-three percent patients with triple vessel disease and 50% patients with double vessel disease on coronary angiography showed CECP. Sensitivity and specificity of CECP for prediction of CAD were 50 and 92.9%, respectively. Conclusion CECP on CEUS can predict CAD and is a more reliable indicator of severe CAD than plaque characteristics on grayscale and Doppler imaging; making it useful for screening of patients at risk of having CAD.

4.
Sci Total Environ ; 946: 174242, 2024 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-38917896

RESUMO

This paper discusses the influence of the digital economy (DE) on carbon emissions based on evidence at the global level. Specifically, based on the panel data from 80 countries from 2010 to 2020, this paper creates a DE measurement index and uses the System-GMM model to assess the influence of DE on carbon emissions. The results show that: (1) The development of DE significantly promotes carbon emissions reduction. (2) The development of DE significantly promotes carbon emissions reduction through technological advancement, structural optimization, and educational enhancement; (3) Regulatory quality and financial development play a positively moderating role in DE's promoting effect on carbon emissions reduction; (4) DE of European and North American nations have stronger promoting effect on carbon emissions reduction than DE of other countries. Compared to DE of developing countries, DE of developed countries has a stronger promoting effect on carbon emissions reduction. Additionally, this paper also finds that institutional differences can impact the carbon emission reduction effects of DE. Based on the results, this paper suggests that governments globally should promote the development of DE and foster international cooperation to enhance DE's driving role in promoting carbon emissions reduction.

5.
J Med Imaging (Bellingham) ; 11(3): 034501, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38737493

RESUMO

Purpose: Current clinical assessment qualitatively describes background parenchymal enhancement (BPE) as minimal, mild, moderate, or marked based on the visually perceived volume and intensity of enhancement in normal fibroglandular breast tissue in dynamic contrast-enhanced (DCE)-MRI. Tumor enhancement may be included within the visual assessment of BPE, thus inflating BPE estimation due to angiogenesis within the tumor. Using a dataset of 426 MRIs, we developed an automated method to segment breasts, electronically remove lesions, and calculate scores to estimate BPE levels. Approach: A U-Net was trained for breast segmentation from DCE-MRI maximum intensity projection (MIP) images. Fuzzy c-means clustering was used to segment lesions; the lesion volume was removed prior to creating projections. U-Net outputs were applied to create projection images of both, affected, and unaffected breasts before and after lesion removal. BPE scores were calculated from various projection images, including MIPs or average intensity projections of first- or second postcontrast subtraction MRIs, to evaluate the effect of varying image parameters on automatic BPE assessment. Receiver operating characteristic analysis was performed to determine the predictive value of computed scores in BPE level classification tasks relative to radiologist ratings. Results: Statistically significant trends were found between radiologist BPE ratings and calculated BPE scores for all breast regions (Kendall correlation, p<0.001). Scores from all breast regions performed significantly better than guessing (p<0.025 from the z-test). Results failed to show a statistically significant difference in performance with and without lesion removal. BPE scores of the affected breast in the second postcontrast subtraction MIP after lesion removal performed statistically greater than random guessing across various viewing projections and DCE time points. Conclusions: Results demonstrate the potential for automatic BPE scoring to serve as a quantitative value for objective BPE level classification from breast DCE-MR without the influence of lesion enhancement.

6.
Neuroimaging Clin N Am ; 34(2): 225-240, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38604707

RESUMO

The evaluation of unruptured intracranial aneurysms requires a comprehensive and multifaceted approach. The comprehensive analysis of aneurysm wall enhancement through high-resolution MRI, in tandem with advanced processing techniques like finite element analysis, quantitative susceptibility mapping, and computational fluid dynamics, has begun to unveil insights into the intricate biology of aneurysms. This enhanced understanding of the etiology, progression, and eventual rupture of aneurysms holds the potential to be used as a tool to triage patients to intervention versus observation. Emerging tools such as radiomics and machine learning are poised to contribute significantly to this evolving landscape of diagnostic refinement.


Assuntos
Aneurisma Roto , Aneurisma Intracraniano , Humanos , Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Roto/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Fatores de Risco
7.
Br J Soc Psychol ; 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38634756

RESUMO

Using a variant of the hide-and-seek game, we show in three studies that self-enhancement can help or hinder strategic thinking. In this guessing game, one player chooses a number while another player tries to guess it. Each player does this either in a random fashion (throwing a mental die) or by active thinking. The structure of the game implies that guessers benefit from thinking about a number, whereas choosers are disadvantaged. Yet, regardless of their role, respondents prefer to actively think about a number. For choosers, the belief they can outthink the opponent amounts to self-enhancement, whereas for guessers, the same belief can be rationally justified. We discuss the implications of the findings for theories of strategic cognition and applications to real-world contexts.

8.
Sensors (Basel) ; 24(8)2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38676026

RESUMO

This work presents a novel multielectrode array (MEA) to quantitatively assess the dose enhancement factor (DEF) produced in a medium by embedded nanoparticles. The MEA has 16 nanocrystalline diamond electrodes (in a cell-culture well), and a single-crystal diamond divided into four quadrants for X-ray dosimetry. DEF was assessed in water solutions with up to a 1000 µg/mL concentration of silver, platinum, and gold nanoparticles. The X-ray detectors showed a linear response to radiation dose (r2 ≥ 0.9999). Overall, platinum and gold nanoparticles produced a dose enhancement in the medium (maximum of 1.9 and 3.1, respectively), while silver nanoparticles produced a shielding effect (maximum of 37%), lowering the dose in the medium. This work shows that the novel MEA can be a useful tool in the quantitative assessment of radiation dose enhancement due to nanoparticles. Together with its suitability for cells' exocytosis studies, it proves to be a highly versatile device for several applications.


Assuntos
Diamante , Eletrodos , Ouro , Nanopartículas Metálicas , Diamante/química , Nanopartículas Metálicas/química , Ouro/química , Prata/química , Platina/química , Doses de Radiação , Humanos , Raios X , Nanopartículas/química
9.
Eur Radiol ; 2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38683385

RESUMO

OBJECTIVES: To compare the quantitative background parenchymal enhancement (BPE) in women with different lifetime risks and BRCA mutation status of breast cancer using screening MRI. MATERIALS AND METHODS: This study included screening MRI of 535 women divided into three groups based on lifetime risk: nonhigh-risk women, high-risk women without BRCA mutation, and BRCA1/2 mutation carriers. Six quantitative BPE measurements, including percent enhancement (PE) and signal enhancement ratio (SER), were calculated on DCE-MRI after segmentation of the whole breast and fibroglandular tissue (FGT). The associations between lifetime risk factors and BPE were analyzed via linear regression analysis. We adjusted for risk factors influencing BPE using propensity score matching (PSM) and compared the BPE between different groups. A two-sided Mann-Whitney U-test was used to compare the BPE with a threshold of 0.1 for multiple testing issue-adjusted p values. RESULTS: Age, BMI, menopausal status, and FGT level were significantly correlated with quantitative BPE based on the univariate and multivariable linear regression analyses. After adjusting for age, BMI, menopausal status, hormonal treatment history, and FGT level using PSM, significant differences were observed between high-risk non-BRCA and BRCA groups in PEFGT (11.5 vs. 8.0%, adjusted p = 0.018) and SERFGT (7.2 vs. 9.3%, adjusted p = 0.066). CONCLUSION: Quantitative BPE varies in women with different lifetime breast cancer risks and BRCA mutation status. These differences may be due to the influence of multiple lifetime risk factors. Quantitative BPE differences remained between groups with and without BRCA mutations after adjusting for known risk factors associated with BPE. CLINICAL RELEVANCE STATEMENT: BRCA germline mutations may be associated with quantitative background parenchymal enhancement, excluding the effects of known confounding factors. This finding can provide potential insights into the cancer pathophysiological mechanisms behind lifetime risk models. KEY POINTS: Expanding understanding of breast cancer pathophysiology allows for improved risk stratification and optimized screening protocols. Quantitative BPE is significantly associated with lifetime risk factors and differs between BRCA mutation carriers and noncarriers. This research offers a possible understanding of the physiological mechanisms underlying quantitative BPE and BRCA germline mutations.

10.
Sci Total Environ ; 930: 172744, 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38685429

RESUMO

The evaluation of the vulnerability of coupled socio-ecological systems is critical for addressing and preventing the adverse impacts of various environmental hazards and devising strategies for climate change adaptation. The initial step in vulnerability assessment involves exposure assessment, which entails quantifying and mapping the risks posed by multiple environmental hazards, thereby offering valuable insights for the implementation of vulnerability assessment methodologies. Consequently, this study sought to model the exposure of coupled social-ecological systems in mountainous regions to various environmental hazards. By a set of socio-economic, climatic, geospatial, hydrological, and demographic data, as well as satellite imagery, and examining 11 hazards, including droughts, pests, dust storms, winds, extreme temperatures, evapotranspiration, landslides, floods, wildfires, and social vulnerability, this research employed machine learning (ML) techniques and the fuzzy analytical hierarchy process (FAHP). Expert opinions were utilized to guide hazard weighting and calculate the exposure index (EI). Through the precise spatial mapping of EI variations across the socio-ecological systems in mountainous areas, this investigation provides insights into vulnerability to multiple environmental hazards, thereby laying the groundwork for future endeavors in supporting national-level vulnerability assessments aimed at fostering sustainable environments. The findings reveal that social vulnerability and pests receive the highest weighting, while floods and landslides are ranked lower. All hazards demonstrate significant correlations with the EI, with droughts exhibiting the strongest correlation (r > 0.81). Spatial analysis indicates a north-south gradient in forest exposure, with southern regions showing higher exposure hotspots (EI 29.08) compared to northern areas (EI 10.60). Validation based on Area Under Curve (AUC) and Consistency Rate (CR) in FAHP demonstrates robustness, with AUC values exceeding 0.78 and CR values below 0.1. Considering the anticipated intensification of hazards, management strategies should prioritize reducing social vulnerability, restore degraded areas using drought-resistant species, combat pests, and mitigate desertification. By integrating multidisciplinary data and expert opinions, this research contributes to informed decision-making regarding sustainable forest management and climate resilience in mountain ecosystems.

11.
Diagnostics (Basel) ; 14(6)2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38535064

RESUMO

Mitral regurgitation (MR), a primary cause of valvular disease in adults, affects millions and is growing due to an ageing population. Cardiovascular magnetic resonance (CMR) has emerged as an essential tool, offering insights into valvular and myocardial pathology when compared to the primary imaging modality, echocardiography. This review highlights CMR's superiority in high-resolution volumetric assessment and tissue characterization, including also advanced techniques like late gadolinium enhancement imaging, parametric mapping, feature tracking and 4D flow analysis. These techniques provide a deeper understanding of MR's pathophysiology and its effect on cardiac chambers, enabling CMR to surpass echocardiography in predicting hard clinical outcomes and left ventricular (LV) remodelling post mitral valve surgery. Despite its advantages, CMR's application faces limitations like cost, lack of standardization, and susceptibility to arrhythmia artifacts. Nonetheless, as technological advancements continue and new evidence emerges, CMR's role in MR assessment is set to expand, offering a more nuanced and personalized approach to cardiac care. This review emphasizes the need for further research and standardized protocols to maximize CMR's potential in MR management.

12.
J Environ Manage ; 357: 120713, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38552520

RESUMO

With the continuous advancement of urban renewal, the application of recycled aggregates (RA) is a win-win measure to solve the treatment of construction waste and provide the required building materials. However, the existence of a large amount of old adhesive mortar (OAM) makes it difficult for RA to equivalently replace natural aggregates (NA) due to their higher water absorption and crushing index, as well as a lower apparent density. From the published literature on enhancing RA, the most mature and easiest method for construction is physical enhancement technology. Therefore, through a review of recent related researches, this article summarizes and compares the modification effects of mechanical grinding technology, traditional heating and grinding technology, and microwave heating technology on the physical properties of RA, including water absorption, apparent density, and crushing value. The related modification mechanisms were discussed. Additionally, the impacts of different physical enhancement technologies on the environment and economy effects are assessed from the perspectives of carbon emissions and cost required during processing. Based on multi-criteria analysis, microwave heating technology is more efficient and cleaner, which is the most recommended in the future.


Assuntos
Resíduos Industriais , Reciclagem , Resíduos Industriais/análise , Reciclagem/métodos , Materiais de Construção , Água , Desempenho Físico Funcional
13.
Med Oncol ; 41(5): 95, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38526657

RESUMO

5-Fluorouracil (5-FU) is an anticancer agent belonging to BCS Class III that exhibits poor release characteristics and low retention in the biological system. The main objective of this investigation was to develop a drug delivery system, i.e., Nanostructure Lipid Carriers (NLCs) loaded with 5-FU to prolong its biological retention through 5-FU-loaded NLCs (5-FUNLC) were designed to manipulate physicochemical characteristics and assessment of in vitro and in vivo performance. The developed NLCs underwent comprehensive characterization, including assessments for particle size, zeta potential, morphological evaluation, and FT-IR spectroscopy. Additionally, specific evaluations were conducted for 5-FUNLCs, encompassing analyses for encapsulation efficiency of the drug, release characteristics in PBS at pH 6.8, and stability study. The lipophilic character of 5-FUNLC was confirmed through the measurement of the partition coefficient (log P). 5-FUNLCs were observed as spherical-shaped particles with a mean size of 300 ± 25 nm. The encapsulation efficiency was determined to be 89%, indicating effective drug loading within the NLCs. Furthermore, these NLCs exhibited a sustained release nature lasting up to 3-4 h, indicating their potential for controlled drug release over time. Lipid components were biocompatible with the 5-FU to determine thermal transition temperature and show good stability for 30 days. Additionally, an in vitro hemolysis study that confirmed the system did not cause any destruction to the RBCs during intravenous administration. The drug's gut permeability was assessed utilizing the optimized 5-FUNLC (F2) in comparison to 5-FU through the intestine or gut sac model (in the apical to basolateral direction, A → B). The permeability coefficient was measured as 4.91 × 10-5 cm/h with a significant difference. Additionally, the antioxidant potential of the NLCs was demonstrated through the DPPH method. The NLCs' performance was further assessed through in vivo pharmacokinetic studies on Wistar Rats, resulting in a 1.5-fold enhancement in their activity compared to free 5-FU. These NLCs offer improved drug solubility and sustained release, which collectively contribute to enhanced therapeutic outcomes and modulate bioavailability. The study concludes by highlighting the potential of 5-FUNLC as an innovative and efficient drug delivery system. The findings suggest that further preclinical investigations are warranted, indicating a promising avenue for the development of more effective and well-tolerated treatments for cancer.


Assuntos
Portadores de Fármacos , Nanoestruturas , Ratos , Animais , Liberação Controlada de Fármacos , Portadores de Fármacos/química , Fluoruracila , Preparações de Ação Retardada , Disponibilidade Biológica , Ratos Wistar , Espectroscopia de Infravermelho com Transformada de Fourier , Hemólise , Lipídeos , Nanoestruturas/química , Permeabilidade
14.
Magn Reson Imaging ; 109: 256-263, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38522623

RESUMO

PURPOSE: Joint bright- and black-blood MRI techniques provide improved scar localization and contrast. Black-blood contrast is obtained after the visual selection of an optimal inversion time (TI) which often results in uncertainties, inter- and intra-observer variability and increased workload. In this work, we propose an artificial intelligence-based algorithm to enable fully automated TI selection and simplify myocardial scar imaging. METHODS: The proposed algorithm first localizes the left ventricle using a U-Net architecture. The localized left cavity centroid is extracted and a squared region of interest ("focus box") is created around the resulting pixel. The focus box is then propagated on each image and the sum of the pixel intensity inside is computed. The smallest sum corresponds to the image with the lowest intensity signal within the blood pool and healthy myocardium, which will provide an ideal scar-to-blood contrast. The image's corresponding TI is considered optimal. The U-Net was trained to segment the epicardium in 177 patients with binary cross-entropy loss. The algorithm was validated retrospectively in 152 patients, and the agreement between the algorithm and two magnetic resonance (MR) operators' prediction of TI values was calculated using the Fleiss' kappa coefficient. Thirty focus box sizes, ranging from 2.3mm2 to 20.3cm2, were tested. Processing times were measured. RESULTS: The U-Net's Dice score was 93.0 ± 0.1%. The proposed algorithm extracted TI values in 2.7 ± 0.1 s per patient (vs. 16.0 ± 8.5 s for the operator). An agreement between the algorithm's prediction and the MR operators' prediction was found in 137/152 patients (κ= 0.89), for an optimal focus box of size 2.3cm2. CONCLUSION: The proposed fully-automated algorithm has potential of reducing uncertainties, variability, and workload inherent to manual approaches with promise for future clinical implementation for joint bright- and black-blood MRI.


Assuntos
Meios de Contraste , Gadolínio , Humanos , Estudos Retrospectivos , Cicatriz/diagnóstico por imagem , Inteligência Artificial , Miocárdio/patologia , Imageamento por Ressonância Magnética/métodos
15.
Gastroenterol Rep (Oxf) ; 12: goae002, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38419722

RESUMO

Background: Accurate preoperative evaluation of fistula-in-ano can guide the choice of surgical procedure and may improve healing rates. This prospective study aimed to evaluate the accuracy of conventional 3D transperineal ultrasound (3D-TPUS) compared with SonoVue (SVE)-enhanced 3D-TPUS for the detection and classification of anal fistula. Methods: In this prospective study, 3D-TPUS reconstructions were performed before and after SVE enhancement in 60 patients with fistula-in-ano who intended to undergo surgery at the Department of Anorectal Surgery, Qilu Hospital, Cheeloo College of Medicine, Shandong University (P. R. China) between January 2021 and October 2021. Accuracies of anal fistula classification, complexity classification, detection of anal fistula branches, and detection of internal opening between 3D-TPUS and SVE 3D-TPUS were compared based on a reference standard-intraoperative findings. Results: This study enrolled 60 patients (mean age, 37.1 ± 11.4 years; mean follow-up, 9 ± 3 months). Intraoperative findings showed that the fistula type was intersphincteric in 23 patients (38.3%), trans-sphincteric in 35 (58.3%; 12 high and 23 low), and suprasphincteric in 2 (3.3%). Moreover, 68 internal openings were found. Compared with the accuracy of 3D-TPUS, that of SVE 3D-TPUS was similar in fistula classification [95.0% (57/60) vs 96.7% (58/60), P = 0.392], but significantly higher in internal opening evaluation [80.9% (55/68) vs 97.1% (66/68), P = 0.001], complexity classification [85.0% (51/60) vs 98.3% (59/60), P = 0.018], and detection of fistula branches [70.4% (19/27) vs 92.6% (25/27), P = 0.031]. Conclusions: SVE 3D-TPUS may be a useful examination for patients with perianal fistulae because of its high accuracy and consistency with intraoperative findings, especially in complex fistula-in-ano and difficult cases.

16.
Intern Med ; 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38346744

RESUMO

Objective Although magnetic resonance imaging (MRI) is the gold standard for evaluating abnormal myocardial fibrosis and extracellular volume (ECV) of the left ventricular myocardium (LVM), a similar evaluation has recently become possible using computed tomography (CT). In this study, we investigated the diagnostic accuracy of a new 256-row multidetector CT with a low tube-voltage single energy scan and deep-learning-image reconstruction (DLIR) in detecting abnormal late enhancement (LE) in LVM. Methods We evaluated the diagnostic performance of CT for detecting LE in LVM and compared the results with those of MRI as a reference. We also measured the ECV of the LVM on CT and compared the results with those on MRI. Patients or Materials We analyzed 50 consecutive patients who underwent cardiac CT, including a late-phase scan and MRI, within three months of suspected cardiomyopathy. All patients underwent 256-slice CT (Revolution CT Apex; GE Healthcare) with a low tube-voltage (70 kV) single energy scan and DLIR for a late-phase scan. Results In patient- and segment-based analyses, the sensitivity, specificity, and accuracy of detection of LE on CT were 94% and 85%, 100% and 95%, and 96% and 93%, respectively. The ECV of LVM per patient on CT and MRI was 33.0% ±6.2% and 35.9% ±6.1%, respectively. These findings were extremely strongly correlated, with a correlation coefficient of 0.87 (p <0.0001). The effective radiation dose on late-phase scanning was 2.4±0.9 mSv. Conclusion The diagnostic performance of 256-row multislice CT with a low tube voltage and DLIR for detecting LE and measuring ECV in LVM is credible.

17.
Magn Reson Imaging ; 108: 40-46, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38309379

RESUMO

INTRODUCTION: Cardiac magnetic resonance imaging (MRI), including late gadolinium enhancement (LGE), plays an important role in the diagnosis and prognostication of ischemic and non-ischemic myocardial injury. Conventional LGE sequences require patients to perform multiple breath-holds and require long acquisition times. In this study, we compare image quality and assessment of myocardial LGE using an accelerated free-breathing sequence to the conventional standard-of-care sequence. METHODS: In this prospective cohort study, a total of 41 patients post Coronavirus 2019 (COVID-19) infection were included. Studies were performed on a 1.5 Tesla scanner with LGE imaging acquired using a conventional inversion recovery rapid gradient echo (conventional LGE) sequence followed by the novel accelerated free-breathing (FB-LGE) sequence. Image quality was visually scored (ordinal scale from 1 to 5) and compared between conventional and free-breathing sequences using the Wilcoxon rank sum test. Presence of per-segment LGE was identified according to the American Heart Association 16-segment myocardial model and compared across both conventional LGE and FB-LGE sequences using a two-sided chi-square test. The perpatient LGE extent was also evaluated using both sequences and compared using the Wilcoxon rank sum test. Interobserver variability in detection of per-segment LGE and per-patient LGE extent was evaluated using Cohen's kappa statistic and interclass correlation (ICC), respectively. RESULTS: The mean acquisition time for the FB-LGE sequence was 17 s compared to 413 s for the conventional LGE sequence (P < 0.001). Assessment of image quality was similar between both sequences (P = 0.19). There were no statistically significant differences in LGE assessed using the FB-LGE versus conventional LGE on a per-segment (P = 0.42) and per-patient (P = 0.06) basis. Interobserver variability in LGE assessment for FB-LGE was good for per-segment (= 0.71) and per-patient extent (ICC = 0.92) analyses. CONCLUSIONS: The accelerated FB-LGE sequence performed comparably to the conventional standard-of-care LGE sequence in a cohort of patients post COVID-19 infection in a fraction of the time and without the need for breath-holding. Such a sequence could impact clinical practice by increasing cardiac MRI throughput and accessibility for frail or acutely ill patients unable to perform breath-holding.


Assuntos
COVID-19 , Meios de Contraste , Humanos , Gadolínio , Estudos Prospectivos , Respiração , Imageamento por Ressonância Magnética/métodos , Miocárdio/patologia , COVID-19/diagnóstico por imagem
18.
Radiol Case Rep ; 19(3): 1157-1161, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38259718

RESUMO

Assessment of myocardial viability in patients with myocardial infarction is critical to identify residual ischemic tissue in areas of reduced function and to determine the need for revascularization. We present the case of an 80-year-old man with chest pain and a history of hypertension. Initial evaluation revealed abnormal electrocardiogram findings, and subsequent studies suggested chronic anteroseptal myocardial infarction with reduced cardiac function. Dual-energy cardiac computed tomography was performed to evaluate the coronary arteries and myocardium. Late iodine enhancement images obtained by dual-energy computed tomography showed mixed plaques and severe proximal left anterior descending artery stenosis. Conventional late iodine enhancement imaging was inconclusive, prompting extracellular volume fraction analysis using iodine density imaging. Extracellular volume fraction assessment indicated viable anterior myocardium, leading to successful coronary revascularization. Follow-up demonstrated improved wall motion and ejection fraction. Our study highlights the utility of late iodine enhancement with dual-energy computed tomography in assessing myocardial viability as a noninvasive alternative to magnetic resonance imaging, particularly in patients with contraindications to magnetic resonance imaging. This approach aids in treatment planning, evaluation of efficacy and determination of prognosis in cases of ischemic heart disease.

19.
Brain Sci ; 14(1)2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38248283

RESUMO

Concussion may affect sport performance capabilities related to the visual perception of environmental events, rapid decision-making, and the generation of effective movement responses. Immersive virtual reality (VR) offers a means to quantify, and potentially enhance, the speed, accuracy, and consistency of responses generated by integrated neural processes. A cohort of 24 NCAA Division I male wrestlers completed VR assessments before and after a 3-week VR training program designed to improve their perceptual-motor performance. Prior to training, the intra-individual variability (IIV) among 40 successive task trials for perceptual latency (i.e., time elapsed between visual stimulus presentation and the initiation of movement response) demonstrated strong discrimination between 10 wrestlers who self-reported a history of concussion from 14 wrestlers who denied ever having sustained a concussion (Area Under Curve ≥ 0.750 for neck, arm, and step movements). Natural log transformation improved the distribution normality of the IIV values for both perceptual latency and response time (i.e., time elapsed between visual stimulus presentation and the completion of movement response). The repeated measures ANOVA results demonstrated statistically significant (p < 0.05) pre- and post-training differences between groups for the IIV in perceptual latency and the IIV in response time for neck, arm, and step movements. Five of the six IIV metrics demonstrated a statistically significant magnitude of change for both groups, with large effect sizes. We conclude that a VR assessment can detect impairments in perceptual-motor performance among college wrestlers with a history of concussion. Although significant post-training group differences were evident, VR training can yield significant performance improvements in both groups.

20.
Methods Mol Biol ; 2753: 331-338, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38285348

RESUMO

Aqueous extracts from green seaweeds Chaetomorpha antennina and Ulva flexuosa (SWE) had considerable impacts on the growth and development of tomato plants; it was evident that SWE could be widely applied as agricultural biostimulants as one among a promising strategy of sustainable agriculture. With a higher probability of SWE to replace synthetic agrochemicals, we describe a procedure here to perform an ecotoxicological assessment of liquid SWE on the earthworm, Eudrilus eugeniae Kinb with respect to their growth, survivability, and reproduction.


Assuntos
Clorófitas , Oligoquetos , Alga Marinha , Animais , Verduras , Agricultura
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