Literature on the economic-sociology of illegal markets is progressing convincingly, as scholars identify the need to investigate illegality through the perspective of the market, as well as through ...the perspective of the actor. In this book review essay, two recent publications are reflected upon: The Architecture of Illegal Markets: Towards an Economic Sociology of Illegality in the Economy (Beckert and Dewey, 2017) and Illegal Markets, Violence, and Inequality: Evidence from a Brazilian Metropolis (Daudelin and Ratton, 2018). While the books undertake a different journey through the field of illegal markets, they reach the same theoretical destination, concluding that illegal markets are not homogenous and cannot be boxed into preconceived generalisations.
Surgical resection remains the most important curative treatment for liver tumors; however, it harbors the risk of developing posthepatectomy liver failure. The principal risk is associated with the ...quality and quantity of the future remnant liver. Therefore, preoperative assessment of the future remnant liver is essential in patients scheduled for major liver resection. Technetium-99m mebrofenin hepatobiliary scintigraphy (HBS) in combination with single-photon emission computed tomography/computed tomography is increasingly applied for the quantitative assessment of liver function before major liver surgery. This dynamic quantitative liver function test allows assessment of both total and regional liver function, represented by the hepatic mebrofenin uptake rate, thereby assisting in adequate patient selection. Since routine implementation, it has shown to reduce the risk of posthepatectomy liver failure and has proven to be more valuable than volumetric assessment. To ensure optimal and reproducible results that can be compared across different centers, it is crucial to standardize the methodology and ensure practical applicability of this technique, thereby facilitating external validation and multicenter trials. This article provides an overview of the HBS methodology used at some of the largest HBS centers and covers practical details in the application of HBS for the quantitative scintigraphic assessment of liver function.
Coronary Arterial 18F-Sodium Fluoride Uptake Dweck, Marc R., MD; Chow, Marcus W.L; Joshi, Nikhil V., MD ...
Journal of the American College of Cardiology,
04/2012, Letnik:
59, Številka:
17
Journal Article
Recenzirano
Odprti dostop
Objectives With combined positron emission tomography and computed tomography (CT), we investigated coronary arterial uptake of 18F-sodium fluoride (18F-NaF) and 18F-fluorodeoxyglucose (18F-FDG) as ...markers of active plaque calcification and inflammation, respectively. Background The noninvasive assessment of coronary artery plaque biology would be a major advance particularly in the identification of vulnerable plaques, which are associated with specific pathological characteristics, including micro-calcification and inflammation. Methods We prospectively recruited 119 volunteers (72 ± 8 years of age, 68% men) with and without aortic valve disease and measured their coronary calcium score and 18F-NaF and 18F-FDG uptake. Patients with a calcium score of 0 were used as control subjects and compared with those with calcific atherosclerosis (calcium score >0). Results Inter-observer repeatability of coronary 18F-NaF uptake measurements (maximum tissue/background ratio) was excellent (intra-class coefficient 0.99). Activity was higher in patients with coronary atherosclerosis (n = 106) versus control subjects (1.64 ± 0.49 vs. 1.23 ± 0.24; p = 0.003) and correlated with the calcium score (r = 0.652, p < 0.001), although 40% of those with scores >1,000 displayed normal uptake. Patients with increased coronary 18F-NaF activity (n = 40) had higher rates of prior cardiovascular events (p = 0.016) and angina (p = 0.023) and higher Framingham risk scores (p = 0.011). Quantification of coronary 18F-FDG uptake was hampered by myocardial activity and was not increased in patients with atherosclerosis versus control subjects (p = 0.498). Conclusions 18F-NaF is a promising new approach for the assessment of coronary artery plaque biology. Prospective studies with clinical outcomes are now needed to assess whether coronary 18F-NaF uptake represents a novel marker of plaque vulnerability, recent plaque rupture, and future cardiovascular risk. (An Observational PET/CT Study Examining the Role of Active Valvular Calcification and Inflammation in Patients With Aortic Stenosis; NCT01358513 )
With combined positron emission tomography and computed tomography (CT), we investigated coronary arterial uptake of 18F-sodium fluoride (18F-NaF) and 18F-fluorodeoxyglucose (18F-FDG) as markers of ...active plaque calcification and inflammation, respectively.
The noninvasive assessment of coronary artery plaque biology would be a major advance particularly in the identification of vulnerable plaques, which are associated with specific pathological characteristics, including micro-calcification and inflammation.
We prospectively recruited 119 volunteers (72 ± 8 years of age, 68% men) with and without aortic valve disease and measured their coronary calcium score and 18F-NaF and 18F-FDG uptake. Patients with a calcium score of 0 were used as control subjects and compared with those with calcific atherosclerosis (calcium score >0).
Inter-observer repeatability of coronary 18F-NaF uptake measurements (maximum tissue/background ratio) was excellent (intra-class coefficient 0.99). Activity was higher in patients with coronary atherosclerosis (n = 106) versus control subjects (1.64 ± 0.49 vs. 1.23 ± 0.24; p = 0.003) and correlated with the calcium score (r = 0.652, p < 0.001), although 40% of those with scores >1,000 displayed normal uptake. Patients with increased coronary 18F-NaF activity (n = 40) had higher rates of prior cardiovascular events (p = 0.016) and angina (p = 0.023) and higher Framingham risk scores (p = 0.011). Quantification of coronary 18F-FDG uptake was hampered by myocardial activity and was not increased in patients with atherosclerosis versus control subjects (p = 0.498).
18F-NaF is a promising new approach for the assessment of coronary artery plaque biology. Prospective studies with clinical outcomes are now needed to assess whether coronary 18F-NaF uptake represents a novel marker of plaque vulnerability, recent plaque rupture, and future cardiovascular risk. (An Observational PET/CT Study Examining the Role of Active Valvular Calcification and Inflammation in Patients With Aortic Stenosis; NCT01358513).
The pathophysiology of aortic stenosis is incompletely understood, and the relative contributions of valvular calcification and inflammation to disease progression are unknown.
Patients with aortic ...sclerosis and mild, moderate, and severe stenosis were compared prospectively with age- and sex-matched control subjects. Aortic valve severity was determined by echocardiography. Calcification and inflammation in the aortic valve were assessed by 18F-sodium fluoride (18F-NaF) and 18F-fluorodeoxyglucose (18F-FDG) uptake with the use of positron emission tomography. One hundred twenty-one subjects (20 controls; 20 aortic sclerosis; 25 mild, 33 moderate, and 23 severe aortic stenosis) were administered both 18F-NaF and 18F-FDG. Quantification of tracer uptake within the valve demonstrated excellent interobserver repeatability with no fixed or proportional biases and limits of agreement of ±0.21 (18F-NaF) and ±0.13 (18F-FDG) for maximum tissue-to-background ratios. Activity of both tracers was higher in patients with aortic stenosis than in control subjects (18F-NaF: 2.87±0.82 versus 1.55±0.17; 18F-FDG: 1.58±0.21 versus 1.30±0.13; both P<0.001). 18F-NaF uptake displayed a progressive rise with valve severity (r(2)=0.540, P<0.001), with a more modest increase observed for 18F-FDG (r(2)=0.218, P<0.001). Among patients with aortic stenosis, 91% had increased 18F-NaF uptake (>1.97), and 35% had increased 18F-FDG uptake (>1.63). A weak correlation between the activities of these tracers was observed (r(2)=0.174, P<0.001).
Positron emission tomography is a novel, feasible, and repeatable approach to the evaluation of valvular calcification and inflammation in patients with aortic stenosis. The frequency and magnitude of increased tracer activity correlate with disease severity and are strongest for 18F-NaF.
http://www.clinicaltrials.gov. Unique identifier: NCT01358513.
18F-Sodium fluoride (18F-NaF) and 18F-fluorodeoxyglucose (18F-FDG) are promising novel biomarkers of disease activity in aortic stenosis. We compared 18F-NaF and 18F-FDG uptake with histological ...characterization of the aortic valve and assessed whether they predicted disease progression.
Thirty patients with aortic stenosis underwent combined positron emission and computed tomography using 18F-NaF and 18F-FDG radiotracers. In 12 patients undergoing aortic valve replacement surgery (10 for each tracer), radiotracer uptake (mean tissue/
=0.65; P=0.04) and osteocalcin (r=0.68; P=0.03) immunohistochemistry. There was no significant correlation between 18F-FDG uptake and CD68 staining (r=-0.43; P=0.22). After 1 year, aortic valve calcification increased from 314 (193-540) to 365 (207-934) AU (P<0.01). Baseline 18F-NaF uptake correlated closely with the change in calcium score (r=0.66; P<0.01), and this improved further (r=0.75; P<0.01) when 18F-NaF uptake overlying computed tomography-defined macrocalcification was excluded. No significant correlation was noted between valvular 18F-FDG uptake and change in calcium score (r=-0.11; P=0.66).
18F-NaF uptake identifies active tissue calcification and predicts disease progression in patients with calcific aortic stenosis.
URL: http://www.clinicaltrials.gov. Unique identifier: NCT01358513.
Depletion of monocytes reduces LPS-induced lung inflammation in mice, suggesting monocytes as potential therapeutic targets in acute lung injury.
To investigate whether depletion of circulating blood ...monocytes has beneficial effects on markers of systemic and pulmonary inflammation in a human model of acute lung inflammation.
A total of 30 healthy volunteers were enrolled in a randomized controlled trial. Volunteers inhaled LPS at baseline, and were randomized to receive active mononuclear cell depletion by leukapheresis, or sham leukapheresis, in a double-blind fashion (15 volunteers per group). Serial blood counts were measured, bronchoalveolar lavage (BAL) was performed at 9 hours, and (18)Ffluorodeoxyglucose positron emission tomography at 24 hours. The primary endpoint was the increment in circulating neutrophils at 8 hours.
As expected, inhalation of LPS induced neutrophilia and an up-regulation of inflammatory mediators in the blood and lungs of all volunteers. There was no significant difference between the depletion and sham groups in the mean increment in blood neutrophil count at 8 hours (6.16 × 10(9)/L and 6.15 × 10(9)/L, respectively; P = 1.00). Furthermore, there were no significant differences in BAL neutrophils or protein, positron emission tomography-derived measures of global lung inflammation, or cytokine levels in plasma or BAL supernatant between the study groups. No serious adverse events occurred, and no symptoms were significantly different between the groups.
These findings do not support a role for circulating human monocytes in the early recruitment of neutrophils during LPS-mediated acute lung inflammation in humans.
Conclusion 18F-NaF is a marker of active calcification and disease progression in patients with aortic stenosis with major potential for assessing novel therapeutic strategies.
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