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991.
Antonio Esposito Anna Palmisano Sofia Antunes Caterina Colantoni Paola Maria Vittoria Rancoita Davide Vignale Francesca Baratto Paolo Della Bella Alessandro Del Maschio Francesco De Cobelli 《Molecular imaging and biology》2018,20(5):816-825
Purpose
Diffuse remodeling of myocardial extra-cellular matrix is largely responsible for left ventricle (LV) dysfunction and arrhythmias. Our hypothesis is that the texture analysis of late iodine enhancement (LIE) cardiac computed tomography (cCT) images may improve characterization of the diffuse extra-cellular matrix changes. Our aim was to extract volumetric extracellular volume (ECV) and LIE texture features of non-scarred (remote) myocardium from cCT of patients with recurrent ventricular tachycardia (rVT), and to compare these radiomic features with LV-function, LV-remodeling, and underlying cardiac disease.Procedures
Forty-eight patients suffering from rVT were prospectively enrolled: 5/48 with idiopathic VT (IVT), 23/48 with post-ischemic dilated cardiomyopathy (ICM), 9/48 with idiopathic dilated cardiomyopathy (IDCM), and 11/48 with scars from a previous healed myocarditis (MYO). All patients underwent echocardiography to assess LV systolic and diastolic function and cCT with pre-contrast, angiographic, and LIE scan to obtain end-diastolic volume (EDV), ECV, and first-order texture parameters of Hounsfield Unit (HU) of remote myocardium in LIE [energy, entropy, HU-mean, HU-median, standard deviation (SD), and mean absolute deviation (MAD)].Results
Energy, HU mean, and HU median by cCT texture analysis correlated with ECV (rho?=?0.5650, rho?=?0.5741, rho?=?0.5068; p?<?0.0005). cCT-derived ECV, HU-mean, HU-median, SD, and MAD correlated directly to EDV by cCT and inversely to ejection fraction by echocardiography (p?<?0.05). SD and MAD correlated with diastolic function by echocardiography (rho?=?0.3837, p?=?0.0071; rho?=?0.3330, p?=?0.0208). MYO and IVT patients were characterized by significantly lower values of SD and MAD when compared with ICM and IDCM patients, independently of LV-volume systolic and diastolic function.Conclusions
Texture analysis of LIE may expand cCT capability of myocardial characterization. Myocardial heterogeneity (SD and MAD) was associated with LV dilatation, systolic and diastolic function, and is able to potentially identify the different patterns of structural remodeling characterizing patients with rVT of different etiology.992.
Sheung-Fat Ko Hon-Kan Yip Chen-Chang Lee Chia-Chang Lee Chia-Hao Su Chung-Cheng Huang Shu-Hang Ng Yi-Ling Chen Min-Chi Chen 《Molecular imaging and biology》2018,20(5):750-760
Purpose
This study aimed to investigate the potential of apparent diffusion coefficient (ADC) for monitoring adipose-derived mesenchymal stem cell (ADMSC) therapy of renal ischemic-reperfusion injury (IRI).Procedures
After baseline magnetic resonance imaging (MRI), 36 Sprague-Dawley rats with bilateral renal IRI were divided equally as groups 1, 2, and 3 (non-treated rats) and groups 4, 5, and 6 (ADMSC-treated rats, with 2 million ADMSCs injected via the tail vein at 6 h after IRI). Groups 1 and 4, 2 and 5, and 3 and 6 were euthanized at days 1, 3, and 7, respectively, after renal MRI. The ratios of ADC at different time points to baseline values in the cortex, outer, and inner stripes of outer medulla (OSOM/ISOM), assessments of monocyte chemoattractant protein-1 (MCP-1), CD68+ cells, tubular cast formation, and degree of fibrosis in three zones over time were compared between the non-treated and ADMSC-treated rats.Results
Among three zones, the differences in cortical ADC and immunohistochemical changes between the non-treated and ADMSC-treated IRI rats over time were less obvious. Compared with the non-treated rats, the ADMSC-treated rats exhibited significantly higher ADC ratios of OSOM and ISOM at days 1 and 3 corresponding to significantly less MCP-1 staining, CD68+ cells, and tubular casts. From day 3 to day 7, coupling with the decrement of MCP-1 and CD68+ cells in IRI kidneys, the effect of cell density on ADC declined. By day 7, the ADMSC-treated rats showed significantly higher ADC ratios of ISOM than the non-treated IRI rats, indicating better recovery, which could be related to significantly fewer tubular casts and marked amelioration of fibrosis.Conclusions
We suggest ADC is a useful in vivo biomarker for monitoring ADMSC therapy of renal IRI.993.
Yvonne W. S. Jauw Dennis F. Heijtel Josée M. Zijlstra Otto S. Hoekstra Henrica C. W. de Vet Danielle J. Vugts Henk M. Verheul Ronald Boellaard Sonja Zweegman Guus A. M. S. van Dongen C. Willemien Menke-van der Houven van Oordt Adriaan A. Lammertsma Marc C. Huisman 《Molecular imaging and biology》2018,20(6):1025-1034
Purpose
Positron emission tomography (PET) with Zirconium-89 (Zr-89)-labeled antibodies can be used for in vivo quantification of antibody uptake. Knowledge about measurement variability is required to ensure correct interpretation. However, no clinical studies have been reported on measurement variability of Zr-89 immuno-PET. As variability due to low signal-to-noise is part of the total measurement variability, the aim of this study was to assess noise-induced variability of Zr-89 -immuno-PET using count-reduced clinical images.Procedures
Data were acquired from three previously reported clinical studies with [89Zr]antiCD20 (74 MBq, n?=?7), [89Zr]antiEGFR (37 MBq, n?=?7), and [89Zr]antiCD44 (37 MBq, n?=?13), with imaging obtained 1 to 6 days post injection (D0–D6). Volumes of interest (VOIs) were manually delineated for liver, spleen, kidney, lung, brain, and tumor. For blood pool and bone marrow, fixed-size VOIs were used. Original PET list mode data were split and reconstructed, resulting in two count-reduced images at 50 % of the original injected dose (e.g., 37 MBq74inj).Repeatability coefficients (RC) were obtained from Bland-Altman analysis on standardized uptake values (SUV) derived from VOIs applied to these images.Results
The RC for the combined manually delineated organs for [89Zr] antiCD20 (37 MBq74inj) increased from D0 to D6 and was less than 6 % at all time points. Blood pool and bone marrow had higher RC, up to 43 % for 37 MBq74inj at D6. For tumor, the RC was up to 42 % for [89Zr]antiCD20 (37 MBq74inj). For [89Zr]antiCD20, (18 MBq74inj), [89Zr]antiEGFR (18 MBq37inj), and [89Zr]antiCD44 (18 MBq37inj), measurement variability was independent of the investigated antibody.Conclusions
Based on this study, noise-induced variability results in a RC for Zr-89-immuno-PET (37 MBq) around 6 % for manually delineated organs combined, increasing up to 43 % at D6 for blood pool and bone marrow, assuming similar biodistribution of antibodies. The signal-to-noise ratio leads to tumor RC up to 42 %.994.
995.
Edward H. Ip Santiago Saldana Thomas A. Arcury Joseph G. Grzywacz Grisel Trejo Sara A. Quandt 《American journal of public health》2015,105(10):e42-e47
Objectives. We recruited 248 farmworker families with preschool-aged children in North Carolina and examined food security indicators over 24 months to identify food security patterns and examine the dynamic of change over time.Methods. Participants in the Niños Sanos study, conducted 2011 to 2014, completed quarterly food security assessments. Based on responses to items in the US Household Food Security Survey Module, we identified different states of food security by using hidden Markov model analysis, and examined factors associated with different states. We delineated factors associated with changes in state by using mixed-effect ordinal logistic regression.Results. About half of the households (51%) consistently stayed in the most food-secure state. The least food-secure state was transient, with only 29% probability of this state for 2 consecutive quarters. Seasonal (vs migrant) work status, having immigration documents (vs not documented), and season predicted higher levels of food security.Conclusions. Heterogeneity in food security among farmworker households calls for tailoring intervention strategies. The transiency and unpredictability of low food security suggest that access to safety-net programs could reduce low food security risk in this population.Farmworkers in the United States experience challenging living conditions and economic insecurity because of low-paying and contingent employment. Although an exact number of farmworkers is not available, estimates place the population at 900 000, plus dependents.1 This includes migrant farmworkers, who establish temporary residences to do farm work, as well as seasonal workers who reside in one place and do farm work during the agricultural season.2 Currently, most farmworkers are Latino and foreign-born,3 which can limit their eligibility and access to food safety-net programs such as the Supplemental Nutrition Assistance Program. In addition, many reside in rural areas where access to healthy food retail stores may be limited by both availability and transportation, although home food production is sometimes possible.4 Together, these create a situation in which farmworker households are likely to experience low food security (resulting from insufficient household resources), but this may be episodic. Children in farmworker households may be particularly vulnerable to the effects of low food security.5Low food security is associated with negative developmental outcomes in infants and toddlers.6 Persistently low food security in early childhood is associated with long-term lower health status.7 For children at school age, this can adversely affect academic performance, weight gain, and social skills.8 With the large population of farmworkers in the United States, food security among their families is an important public health issue.Previous reports of food security for farmworker households have found 20% to 80% to be food insecure.9–14 However, all of these reports have been cross-sectional, and most have used an extended recall period, asking respondents to recall whether their household was food insecure at any time during the past year. Such data provide no information on the duration of food security states or on factors associated with transitions in and out of low food security. Examining food security over time as a dynamic construct is necessary to understand its duration and to develop protective measures for low food security.This repeated-measures study gathered data quarterly for 24 months, and examined different states of food security by using the 18-item US Household Food Security Survey Module.15 Instead of constructing a single score, we used the full item set to form a food security profile. The approach allowed us to delineate several different states of food security within the food security profile, and examine the dynamic of change in food security over the 24-month period. The aims of the study were to (1) describe multiple states of food security of farmworker households, (2) identify factors associated with the different food security states, and (3) delineate the dynamic of change in food security states across a period of 24 months. 相似文献
996.
John E. Pachankis 《Archives of sexual behavior》2015,44(7):1843-1860
Developing and deploying separate treatments for separate conditions seems ill-suited to intervening upon the co-occurring, and possibly functionally similar, psychosocial conditions facing gay and bisexual men. This article argues for the need to create transdiagnostic interventions that reduce multiple syndemic conditions facing gay and bisexual men at the level of their shared source in minority stress pathways. This article first reviews psychosocial syndemic conditions affecting gay and bisexual men, then suggests pathways that might link minority stress to psychosocial syndemics based on recent advancements in emotion science, psychiatric nosology, and cognitive-affective neuroscience, and finally suggests cross-cutting psychosocial treatment principles to reduce minority stress?syndemic pathways among gay and bisexual men. Because minority stress serves as a common basis of all psychosocial syndemic conditions reviewed here, locating the pathways through which minority stress generates psychosocial syndemics and employing overarching treatment principles capable of simultaneously alleviating these pathways will ultimately create a transdiagnostic approach to improving gay and bisexual men’s health. Clinical research and training approaches are suggested to further validate the pathways suggested here, establish the efficacy of treatment approaches tied to those pathways, and generate effective methods for disseminating a transdiagnostic minority stress treatment approach for gay and bisexual men’s psychosocial syndemic health. 相似文献
997.
Robert J. Zeglin 《Archives of sexual behavior》2015,44(7):1979-1990
HIV affects over 1.2 million people in the United States; a substantial number are men who have sex with men (MSM). Despite an abundance of literature evaluating numerous social/structural and individual risk factors associated with HIV for this population, relatively little is known regarding the individual-level role of masculinity in community-level HIV transmission risk. To address this gap, the current analysis systematically reviewed the masculinity and HIV literature for MSM. The findings of 31 sources were included. Seven themes were identified: (1) number of partners, (2) attitudes toward condoms, (3) drug use, (4) sexual positioning, (5) condom decision-making, (6) attitudes toward testing, and (7) treatment compliance. These factors, representing the enactment of masculine norms, potentiate the spread of HIV. The current article aligns these factors into a masculinity model of community HIV transmission. Opportunities for counseling interventions include identifying how masculinity informs a client’s cognitions, emotions, and behaviors as well as adapting gender-transformative interventions to help create new conceptualizations of masculinity for MSM clients. This approach could reduce community-level HIV incidence. 相似文献
998.
Pascal James Imperato 《Journal of community health》2015,40(3):581-596
In 1947, a smallpox outbreak occurred in New York City with a total of twelve cases and two deaths. In order to contain this outbreak, the New York City Department of Health launched a mass immunization campaign that over a period of some 60 days vaccinated 6.35 million people. This article examines in detail the epidemiology of this outbreak and the measures employed to contain it. In 1976, a swine influenza strain was isolated among a few recruits at a US Army training camp at Fort Dix, New Jersey. It was concluded at the time that this virus possibly represented a re-appearance of the 1918 influenza pandemic influenza strain. As a result, a mass national immunization program was launched by the federal government. From its inception, the program encountered a myriad of challenges ranging from doubts that it was even necessary to the development of Guillain-Barré paralysis among some vaccine recipients. This paper examines the planning for and implementation of the swine flu immunization program in New York City. It also compares it to the smallpox vaccination program of 1947. Despite equivalent financial and personnel resources, leadership and organizational skills, the 1976 program only immunized approximately a tenth of the number of New York City residents vaccinated in 1947. The reasons for these marked differences in outcomes are discussed in detail. 相似文献
999.
Gabriella Nosso Brunella Capaldo Sara Cocozza Olga Vaccaro 《Clinical Case Reports》2015,3(12):1030-1033
We show the long‐term efficacy and safety of modified biliopancreatic diversion for the treatment of LPL‐deficiency. How this option compares with gene therapy is difficult to evaluate due to limited experience. Surgery may be the first option in patients in whom medical therapy is ineffective and gene therapy not applicable. 相似文献
1000.
Silvia Udali Annalisa Castagna Michela Corbella Andrea Ruzzenente Sara Moruzzi Filippo Mazzi Tommaso Campagnaro Domenica De Santis Antonia Franceschi Patrizia Pattini Rossella Gottardo Oliviero Olivieri Luigi Perbellini Alfredo Guglielmi Sang‐Woon Choi Domenico Girelli Simonetta Friso 《European journal of clinical investigation》2018,48(2)