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691.
ObjectivesThe authors sought to study the impact of diet and lifestyle intervention on changes in atherosclerotic plaque volume and composition.BackgroundLifestyle and diet modification are the leading strategies to manage coronary artery disease; however, their direct impact on atherosclerosis remains unknown. Coronary plaque composition is related to the risk of future cardiovascular events independent of stenosis severity and can be conveniently evaluated with computed tomography angiography (CTA).MethodsWe enrolled 92 patients (41% women; mean age 60 ± 7.7 years) with nonobstructive (<70% stenosis) coronary atherosclerosis identified by CTA. Participants were randomized (1:1) to either the DISCO (Dietary Intervention to Stop Coronary Atherosclerosis in Computed Tomography) intervention group (systematic follow-up by a dietitian to adhere to the Dietary Approaches to Stop Hypertension nutrition model together with optimal medical therapy [OMT]) or the control group (OMT alone). In all patients, CTA was repeated after 66.9 ± 13.7 weeks. The outcome was change (Δ) in atheroma volume and plaque composition. Based on atherosclerotic tissue attenuation ranges in Hounsfield units (HU), the following components of coronary plaque were distinguished: dense calcium (>351 HU), fibrous plaque (151 to 350 HU), and fibrofatty plaque combined with necrotic core (-30 to 150 HU), referred to as noncalcified plaque.ResultsPercent atheroma volume increased in the control arm (Δ = +1.1 ± 3.4%; p = 0.033) versus no significant change in the experimental arm (Δ = +1.0% ± 4.2%; p = 0.127; intergroup p = 0.851). There was a reduction in noncalcified plaque in both the experimental arm (Δ = ?51.3 ± 79.5 mm3 [?1.7 ± 2.7%]; p < 0.001) and the control arm (Δ = ?21.3 ± 57.7 [?0.7 ± 1.9%]; p = 0.018), which was greater in the DISCO intervention group (intergroup p = 0.045). No differences in fibrous component or dense calcium changes were observed between the groups.ConclusionsControlled diet and lifestyle intervention together with OMT may slow the progression of atherosclerosis and reduce noncalcified plaque volume compared to OMT alone. (Dietary Intervention to Stop Coronary Atherosclerosis in Computed Tomography [DISCO-CT]; NCT02571803)  相似文献   
692.
To assess the anatomical background and significance of incomplete invasive coronary angiography (ICA) and to evaluate the value of coronary computed tomography angiography (CTA) in this scenario. The current study is an analysis of high volume center experience with prospective registry of coronary CTA and ICA. The target population was identified through a review of the electronic database. We included consecutive patients referred for coronary CTA after ICA, which did not visualize at least one native coronary artery or by-pass graft. Between January 2009 and April 2013, 13,603 diagnostic ICA were performed. There were 45 (0.3 %) patients referred for coronary CTA after incomplete ICA. Patients were divided into 3 groups: angina symptoms without previous coronary artery by-pass grafting (CABG) (n = 11,212), angina symptoms with previous CABG (n = 986), and patients prior to valvular surgery (n = 925). ICA did not identify by-pass grafts in 21 (2.2 %) patients and in 24 (0.2 %) cases of native arteries. The explanations for an incomplete ICA included: 11 ostium anomalies, 2 left main spasms, 5 access site problems, 5 ascending aorta aneurysms, and 2 tortuous take-off of a subclavian artery. However, in 20 (44 %) patients no specific reason for the incomplete ICA was identified. After coronary CTA revascularization was performed in 11 (24 %) patients: 6 successful repeat ICA and percutaneous intervention and 5 CABG. Incomplete ICA constitutes rare, but a significant clinical problem. Coronary CTA provides adequate clinical information in these patients.  相似文献   
693.
An athlete’s performance depends not only on the shoes they wear but also on the surface used in sports facilities. In addition, it can significantly contribute to reducing injuries, which are easy to get during sports competitions. In the present study, we wanted to investigate whether recycled styrene butadiene rubber (SBR) and ethylene propylene diene monomer (EPDM) could be used in the production of sports surfaces. For this purpose, we designed three different sports surfaces: (1) SBR covered with a thin EPDM spray layer on the top, (2) clean EPDM, and (3) bottom SBR layer with the top layer of EPDM. The test program of these surfaces included in its scope: shock absorption, vertical deformation, tensile strength, abrasion resistance, and slip resistance tests. Our research also involved the influence of the substrate under surface, temperature, and surface conditions. Presented results show that both materials, in the right proportions, can be used in the production of sports surfaces.  相似文献   
694.
Medulloblastoma spreads by leptomeningeal dissemination rather than by infiltration that characterizes other CNS tumors, eg, gliomas. This study represents an initial attempt to identify both the molecules that mediate medulloblastoma adhesion to leptomeninges and the pathways that are key to survival and proliferation of tumor following adhesion. As a first step in molecule identification, we produced adhesion of D283 medulloblastoma cells to the extracellular matrix (ECM) of H4 glioma cells in vitro. Within this context, D283 cells preferentially expressed the alpha9 and beta1 integrin subunits; antibody and disintegrin blockade of alpha9 and beta1 binding eliminated the adhesion. The H4 ECM was enriched in tenascin, a binding partner for the alpha9beta1 integrin heterodimer. Purified tenascin-C supported D283 cell adhesion. The adhesion was blocked by antibodies to alpha9 and beta1 integrin. In vivo data were similar; immunohistochemistry of primary human medulloblastomas with leptomeningeal extension demonstrated increased expression of alpha9 and beta1 integrins as well as tenascin at the interface of brain and leptomeningeal tumor. These data suggest that tumor-cell expressions of alpha9 and beta1 integrins in combination with extracellular tenascin are necessary for medulloblastoma adhesion to the leptomeninges. As a first step in the identification of pathways that mediate survival and proliferation of tumor following adhesion, we demonstrated that adhesion to H4 ECM was associated with survival and proliferation of D283 cells as well as activation of the MAPK pathway in a growth factor deficient environment. Antibody blockade of alpha9 and beta1 integrin binding that eliminated adhesion also eliminated the in vitro survival benefit. These data suggest that adhesion of medulloblastoma to the meninges is necessary for the survival and proliferation of these tumor cells at the secondary site.  相似文献   
695.
The aim of the study is to verify the hypothesis that genetic polymorphisms are associated with the predisposition to all malignancies. Using as a model breast cancers from the homogenous Polish population (West Pomeranian region) after stratification of 977 patients by age at diagnosis (under 51 years and above 50 years) and by tumour pathology (ductal cancers––low and high grade, lobular cancers, ER-positive/negative) we tested this hypothesis. Altogether 20 different groups of breast cancer cases have been analyzed. The results were compared to a group of unaffected controls that were matched by age, sex, ethnicity and geographical location and originated from families without cancers of any site among relatives. Molecular alterations selected for analyses included those which have been previously recognized as being associated with breast cancer predisposition. Statistically significant differences between the breast cancer cases and controls were observed in 19 of the 20 analyzed groups. Genetic changes were present in more than 90% of the breast cancer patients in 18 of 20 groups. The highest proportion of cases with constitutional changes—99.3% (139/140) was observed for lobular cancers. The number and type of genetic marker and/or the level of their association with the specific cancer predisposition was different between groups. Markers associated with majority of groups included: BRCA1, CHEK2, p53, TNRnTT, FGFRnAA, XPD CC/AA and XPD GG. Some markers appeared to be group specific and included polymorphisms in CDKN2A, CYP1B1, M3K nAA, and RS67. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   
696.
BackgroundThe rapid diagnostics tests for SARS‐CoV‐2 antigen vary in their sensitivities, and moreover, genomic mutations may further affect the performance of the assays. We aimed to evaluate the analytical performance of an automated antigen assay and compare its sensitivity in Delta‐ and Omicron‐variant positive clinical samples.Material and methodsThe analytical performance of an automated mariPOC SARS‐CoV‐2 antigen test was evaluated on a population of community‐dwelling subjects with mild respiratory symptoms or being asymptomatic investigated by the RT‐qPCR Allplex™ SARS‐CoV‐2 assay. The sensitivity and specificity of the antigen test were evaluated on prospective 621 nasopharyngeal swabs along with oropharyngeal swabs. The sensitivity regarding variants determined by the Allplex™ SARS‐CoV‐2 Variant assays was analysed in additional, retrospective 158 Delta and 59 Omicron samples.ResultsThe overall sensitivity of the antigen test in prospective samples was 77.9% (113/145; 95% confidence interval [CI] 70.3–84.4) with the specificity of 99.8% (95% CI 98.8–100). Regarding the variant, the sensitivity was higher in Omicron‐variant samples, 93.2% (55/59; 95% CI 83.5–98.1), compared to Delta‐variant samples, 71.5% (113/158; 95% CI 63.8–78.4; p = .001).ConclusionIn community‐dwelling subjects with mild respiratory symptoms or being asymptomatic, the automated mariPOC SARS‐CoV‐2 antigen test showed high sensitivity over 98.0% in subgroup samples with cycle threshold (Ct) values < 25. Regarding the variant, the antigen test sensitivity was higher in the Omicron‐variant samples compared to the Delta‐variant samples. The analytical performance of the antigen test can differ between the SARS‐CoV‐2 variants, and a re‐evaluation should be performed for new circulating lineages.  相似文献   
697.
The reinforcement of asphalt layers with geosynthetics has been used for several decades, but proper evaluation of the influence of these materials on pavement fatigue life is still a challenging task. The presented study investigates a novel approach to the reinforcement of asphalt layers using a new type of geogrid composite, in which square or hexagonal polypropylene stiff monolithic paving grid with integral junctions is bonded to polypropylene non-woven paving fabric. The laboratory fatigue tests were performed on large asphalt concrete beams reinforced with the new type of geocomposite. Unreinforced samples were used as reference. Test results were analysed in several aspects, including the standardised approach based on stiffness reduction, but also using energy dissipation. The effect of reinforcement on pavement fatigue life was also estimated. Based on the obtained final results of fatigue life calculations, it can be concluded that the evaluated geogrid composites have an evident positive effect on pavement performance and have a significant potential to extend the overall pavement life, especially in the case of hexagonal grid.  相似文献   
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