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Kostas Fasoulas Athanasios Beltsis Taxiarchis Katsinelos Eleni Dimou Mary Arvaniti Anna Charsoula Victor Gourvas Stefanos Atmatzidis Grigoris Chatzimavroudis Panagiotis Katsinelos 《Saudi Journal Of Gastroenterology》2012,18(2):146-148
Mesenteric panniculitis (MP) is a rare inflammatory and fibrotic disease of the mesentery of unknown etiology. It has various clinical and radiological manifestations, posing a diagnostic challenge for clinicians. Its diagnosis is indicated via radiologic imaging and is usually confirmed via peritoneal biopsies. We describe a case of a patient with histopathologically proven MP, in which steroid dependence was successfully managed with colchicine. 相似文献
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Jonathan E. Hickman Niels Andela Kostas Tsigaridis Corinne Galy-Lacaux Money Ossohou Susanne E. Bauer 《Proceedings of the National Academy of Sciences of the United States of America》2021,118(7)
Socioeconomic development in low- and middle-income countries has been accompanied by increased emissions of air pollutants, such as nitrogen oxides [NOx: nitrogen dioxide (NO2) + nitric oxide (NO)], which affect human health. In sub-Saharan Africa, fossil fuel combustion has nearly doubled since 2000. At the same time, landscape biomass burning—another important NOx source—has declined in north equatorial Africa, attributed to changes in climate and anthropogenic fire management. Here, we use satellite observations of tropospheric NO2 vertical column densities (VCDs) and burned area to identify NO2 trends and drivers over Africa. Across the northern ecosystems where biomass burning occurs—home to hundreds of millions of people—mean annual tropospheric NO2 VCDs decreased by 4.5% from 2005 through 2017 during the dry season of November through February. Reductions in burned area explained the majority of variation in NO2 VCDs, though changes in fossil fuel emissions also explained some variation. Over Africa’s biomass burning regions, raising mean GDP density (USD⋅km−2) above its lowest levels is associated with lower NO2 VCDs during the dry season, suggesting that economic development mitigates net NO2 emissions during these highly polluted months. In contrast to the traditional notion that socioeconomic development increases air pollutant concentrations in low- and middle-income nations, our results suggest that countries in Africa’s northern biomass-burning region are following a different pathway during the fire season, resulting in potential air quality benefits. However, these benefits may be lost with increasing fossil fuel use and are absent during the rainy season.Socioeconomic development and population growth in low- and middle-income countries have been widely associated with increased environmental degradation, including rapid increases in emissions of air pollutants (1–3). In contrast, in countries with a high per capita gross domestic product (GDP), various socioeconomic, institutional, and regulatory factors often cause economic growth to be accompanied by reductions of some pollutant emissions, though these emissions may simply be outsourced to lower income countries (4). The relationship between income level and environmental pressure—known as the Environmental Kuznets Curve—has often been conceptualized as an inverted U-shaped curve, but a wide array of functional relationships is possible (3). For emissions of air pollutants, the relationship has generally been described as an inverted U-shaped curve, though carbon dioxide generally does not follow such a curve (3, 5). Some researchers argue that low- and middle-income countries can mitigate or shorten the period of rapid emissions growth that tends to accompany socioeconomic development for at least some pollutants (4). Africa, and sub-Saharan Africa in particular, is characterized by countries with low but growing per capita GDP and rapid population growth, which have been linked to increases in emissions of carbon dioxide and particulate matter (6). As these countries continue their trajectories of economic development, emissions of air pollutants from fossil fuel and biofuel combustion are expected to experience explosive growth (7).Nitrogen dioxide (NO2) is a reactive gas and air pollutant with a lifetime in the atmosphere on the order of hours (8). In the atmosphere, NO2 interconverts rapidly with nitric oxide (NO), and the two species are collectively referred to as NOx. NO2 itself is toxic, is regulated by the US Environmental Protection Agency, and has been associated with premature mortality and asthma [though its direct effects on health are not clear (9) and it may instead function as a proxy for other pollutants, such as ozone and aerosols that have direct health and mortality impacts (10)]. NOx is also a key precursor to the formation of tropospheric ozone (O3), which is damaging to both crop productivity and human health; anthropogenic O3 contributes to roughly half a million premature deaths annually, of which nearly 20,000 are in Africa (11). In addition, NOx is involved in reactions with atmospheric ammonia (NH3) to form nitrate aerosols, which contribute to particulate matter pollution (12) as well as in reactions with volatile organic compounds (VOCs), which form organic nitrates (13). Because of the short lifetime of NO2, and because it can function as an indicator for other pollutants, it can serve as an indicator of overall changes in air quality.NO and NO2 are emitted from a variety of natural and anthropogenic sources. Fossil fuel combustion and anthropogenic alterations to soils through fertilization or livestock management are the primary sources of NOx in many parts of the world. In sub-Saharan Africa (excluding South Africa), fossil fuel combustion and fertilizer use has been considerably lower than elsewhere, and natural soils and biomass burning have historically been more important sources (14). This is true even in Nigeria (15), which experiences substantial emissions of VOCs from the oil and gas industry (16). NOx emissions from Lagos have been shown to be either lower than (15) or comparable to other megacities (17), and NO2 concentrations are generally low during the rainy season, but air quality can become heavily degraded during the biomass burning season (15, 18). However, fossil fuel combustion in the region nearly doubled between 2000 and 2016 (19) and associated emissions of NOx are projected to increase sixfold by 2030 in the absence of regulation, as compared to 2005 levels (7).This increase in fossil fuel combustion is occurring against the backdrop of Africa’s unique, fire-prone savanna ecosystems, home to 70% of the global area burned each year (20). Biomass burning in Africa is estimated to be responsible for NOx emissions of roughly 4 Tg N⋅yr−1, equivalent to about half of all NOx emissions for the continent (21), and one third to half of NOx emissions from biomass burning globally (21–23). The majority of biomass burning in Africa occurs in northern and southern bands of savanna, savanna-forest mosaic, and woodland ecoregions, with a seasonality that follows the migration of the intertropical convergence zone.The early part of the 21st century has been accompanied by a global decline in burned area, with some of the largest declines occurring in Africa’s northern fire band (24). Some of the burned area decline in the northern fire band can be attributed to changes in precipitation that, in turn, affect the quantity and moisture content of available fuels (24–26). However, active anthropogenic suppression of fire has also played an important role (24, 25). Burning is thought to be used as a management strategy—among other uses, humans ignite fires to mineralize nutrients, improve grazing, and reduce fuel loads and the potential for large, uncontrolled fires (27). Increased population density and the introduction of agricultural land into African savanna landscapes—reflecting socioeconomic transitions from traditional nomadic pastoralist lifestyles (28)—have been associated with a sharp decrease in burned area as people either reduce ignition or suppress fires to protect villages and farms, with a reduction in the amount of pasture area to be maintained (25).Unfortunately, sub-Saharan Africa remains a severely understudied region—for example, agricultural soil NO fluxes have only been measured directly for two sites (29, 30), and surface air quality monitoring is extremely limited compared to other parts of the world (31). Remote sensing products provide an important tool for filling some of these data gaps. The short NO2 lifetime in the planetary boundary layer makes it possible to use satellite observations to directly evaluate emissions sources, especially in regions with high temperatures, which tend to shorten the NO2 lifetime, and in relatively polluted regions, where total column densities and surface emissions are highly correlated (ref. 8 and references therein). Although recent remote sensing work has evaluated long-term trends in NO2 concentrations around the world, recent trends in the biomass burning region of northern Africa have not been explicitly evaluated, and the relative impacts of socioeconomic development—the possibility of reduced NOx emissions because of anthropogenic fire suppression and of increasing NOx emissions from growing fossil fuel use—remain unknown. In general, studies on global trends in NO2 tend not to focus on Africa, likely because the regions with the highest NO2 concentrations are in China, Europe, and the United States (e.g., refs. 1, 21). Some earlier studies observed a decline in NO2 VCDs over north equatorial Africa (32, 33), but others did not (34). These and other large-scale studies (e.g., refs. 8, 34, 35) did not identify mechanisms for the observed NO2 dynamics, but rather focused on understanding anthropogenic influences on trends in other regions.Indoor air pollution from biomass combustion for fuel is an important health concern (36). We do not focus on this source. Biofuel combustion is responsible for emissions of 0.6 Tg NO annually across all of Africa (37), which is less than 10% of the magnitude of landscape biomass burning emissions estimated by the Global Fire Emissions Database version 4s [GFED4s (38)] and represents a much smaller proportion of NOx emissions from landscape biomass burning regions during the dry season.Here, we use observations of NO2 by the Ozone Monitoring Instrument [OMI (39)] and burned area from the Moderate Resolution Imaging Spectroradiometer [MODIS (40)] to demonstrate that the recent decline in burned area in the productive savannas of north equatorial Africa—home to over 275 million people—is associated with large declines in tropospheric NO2 VCDs during the biomass burning season from 2005 through 2017, though positive trends explained in part by increasing fossil fuel combustion were observed in other seasons, especially over Nigeria. 相似文献
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Panagiotakos DB Antonogeorgos G Papadimitriou A Anthracopoulos MB Papadopoulos M Konstantinidou M Fretzayas A Priftis KN 《Nutrition, metabolism, and cardiovascular diseases : NMCD》2008,18(9):606-612
Background and aimEating behaviours and obesity status among children have already been evaluated in several studies, with conflicting results. The aim of this study is to assess the correlation of breakfast cereal with childhood obesity.Methods and resultsA representative sample of 700 children (323 male) selected from 18 schools located in Athens greater area were enrolled. Children and their parents completed questionnaires that evaluated dietary habits and physical activity. We also retrieved information about the type of breakfast most frequently consumed. Height and weight of the children was measured and body mass index (BMI) was calculated. Simple and multiple logistic regression methods were used in order to determine the relationship between cereal intake for breakfast and obesity.Some boys (8.6%) and girls (9.0%) were obese, whereas 33.9% of boys and 22.1% of girls were overweight. For boys, the adjusted odds ratio for breakfast cereal intake for being overweight or obese was 0.54 (95% confidence interval (CI): 0.45–1.29), while for girls it was 0.41 (95% CI: 0.21–0.79). Moreover, the odds ratio of overweight/obesity for boys who ate daily breakfast was 0.51 (95% CI: 0.25–1.05), and for girls was 0.27 (95% CI: 0.12–0.64), adjusted for physical activity and other potential confounders.ConclusionThese data provide evidence that breakfast cereal as a most frequent choice, and daily consumption of breakfast, are inversely associated with the prevalence of overweight or obesity in 10–12-year-old children. 相似文献
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Betrosian AP Thireos E Toutouzas K Zabaras P Papadimitriou K Sevastos N 《The American journal of the medical sciences》2004,327(5):250-252
Beriberi, thiamine deficiency, is classified as "dry" (neurologic) or "wet" (cardiovascular) and may be mixed. Deficiency of this vitamin may be nutritional or secondary to alcohol intoxication. In Western societies (occidental beriberi), the disorder is more commonly observed in long-term alcohol abusers. However, it may go undiagnosed because it is relatively uncommon. In some cases (acute cardiovascular beriberi), early treatment with parenteral vitamin B1 is required to prevent the development of low-output state and sudden death. We report a case of occidental beriberi with fatal outcome despite therapy. 相似文献
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A number of studies have shown a high incidence of lung cancer in patients with idiopathic pulmonary fibrosis (9.8 to 38%) compared to control subjects (2 to 6.4%). A similar trend occurs in other entities that affect the interstitial lung compartment, such as systemic sclerosis and sarcoidosis, as well as occupational diseases. The pathogenesis of lung cancer in patients with diffuse pulmonary fibrosis is still unclear. Recent progress in molecular and cellular biology has shed some light on the possible interactions of several types of inflammatory cells, following the deleterious effects of toxic factors leading to alveolitis, and destruction and disorganization of lung parenchyma, which results in fibrosis. Further research in the field would enhance our understanding of the pathogenic mechanisms of cancer development in these patients, and to explain the reason for the different incidence of lung cancer in patients with various interstitial lung diseases. 相似文献
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Efstathios T. Detorakis Kostas Perisinakis Eleni Drakonaki Dimitrios Liakopoulos Antonios Tzedakis Efrosini Papadaki Miltiadis K. Tsilimbaris 《Brachytherapy》2021,20(4):828-834
PurposeBrachytherapy with Ru-106 is widely used for the treatment of intraocular tumors, and its efficacy depends on the accuracy of radioactive plaque placement. Ru-106 plaques are MRI incompatible and create severe metal artifacts on conventional CT scans. Dual-energy CT scans (DECT) may be used to suppress such artifacts. This study examines the possibility of creating fusion images from MRI scans (preoperatively) and DECT scans (with the plaque in place) as a tool for confirming the anatomic accuracy of plaque placement.Methods and MaterialsSix patients with intraocular lesions (5 with choroidal melanoma and 1 with a retinal vasoproliferative lesion) were included. Fusion images of preoperative MRI scans and DECT scans with the plaque in place were created with the Demo version of the ImFusion suite (ImFusion GmbH, Munchen Germany). Clearance margins between the tumor and plaque edge in axial, transverse, and coronal planes as well as the elevation of the posterior plaque edge from the sclera were recorded and associated with the location of the lesion.ResultsPlaque-tumor clearance margins for transverse, sagittal, and coronal planes were higher for anteriorly located lesions (5.13 mm ± 0.11 [5.0–5.2], 5.10 mm ± 0.26 [4.9–5.4], and 5.33 mm ± 0.45 [4.9–5.8] respectively) than for posteriorly located lesions (4.16 mm ± 1.44 [2.5–5.1], 4.13 mm ± 1.42 [2.5–5.1], and 4.2 mm ± 1.21 [2.8–5.0], respectively). The elevation of the posterior plaque edge from the sclera was 0.33 mm ± 0.28 [0–0.5] and 0.63 mm ± 0.60 [0.7–1.2] for posterior and anterior lesions, respectively.ConclusionsFusion images between DECT and MRI scans may be used as a tool to confirm the accuracy of Ru-106 plaque placement in relation with the intraocular tumors in ophthalmic brachytherapy. 相似文献