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81.
Christoph Käcker Alexander Marx Katharina Mössinger Frederike Svehla Ulrike Schneider Pancras Cornelis Wilhelmus Hogendoorn Ole Steen Nielsen Stefan Küffer Christian Sauer Cyril Fisher Christian Hallermann Jörg Thomas Hartmann Jean‐Yves Blay Gunhild Mechtersheimer Peter Hohenberger Philipp Ströbel 《Genes, chromosomes & cancer》2013,52(1):93-98
Irradiation is a major causative factor among the small subgroup of sarcomas with a known etiology. The prognosis of radiation‐induced sarcomas (RIS) is significantly worse than that of their spontaneous counterparts. The most frequent histological subtypes include undifferentiated pleomorphic sarcomas, angiosarcomas, and leiomyosarcomas. A high frequency of MYC amplifications in radiation‐induced angiosarcomas, but not in primary angiosarcomas, has recently been described. To investigate whether MYC amplifications are also frequent in RIS other than angiosarcomas, we analyzed the MYC amplification status of 83 RIS and 192 sporadic sarcomas by fluorescence in situ hybridization. We found significantly higher numbers of MYC amplifications in RIS than in sporadic sarcomas (P < 0.0001), especially in angiosarcomas, undifferentiated pleomorphic sarcomas, and leiomyosarcomas. Angiosarcomas were special in that MYC amplifications were particularly frequent and always high level, while other RIS showed low‐level amplifications. We conclude that MYC amplifications are a frequent feature of RIS as a group and may contribute to the biology of these tumors. © 2012 Wiley Periodicals, Inc. 相似文献
82.
Susan Mikkelsen Khoa Manh Dinh Jens Kjrgaard Boldsen Ole Birger Pedersen Gitte Juel Holst Mikkel Steen Petersen Kathrine Agergrd Kaspersen Bjarne Kuno Mller Kaspar Rene Nielsen Helene Martina Paarup Klaus Rostgaard Henrik Hjalgrim Erik Srensen Linda Jenny Handgaard Thomas Folkmann Hansen Karina Banasik Kristoffer Slvsten Burgdorf Henrik Ullum Torben Sigsgaard Christian Erikstrup 《Clinical and translational allergy》2021,11(1)
BackgroundAllergic rhinitis (AR), allergic conjunctivitis (AC), and asthma composing multiple phenotypes and improved understanding of these phenotypes and their respective risk factors are needed.ObjectivesThe objective of this study was to define the prevalence of AR, AC, and asthma and their association with allergen‐specific immunoglobulin E (sIgE) sensitization in a large cohort of blood donors and identify risk factors.MethodsFrom the nationwide population‐based Danish Blood Donor Study, 52,976 participants completed an electronic questionnaire including AR, AC, asthma, allergic predisposition, and childhood residence. Of these, 25,257 were additionally tested for sIgE to inhalation allergens (Phadiatop).ResultsThe prevalence of sIgE sensitization, AR, AC, and asthma was 30%, 19%, 15%, and 9%, respectively. The youngest birth cohorts had the highest prevalence of sIgE sensitization and symptoms of asthma, AR, and AC, and for asthma, they apparently experienced symptoms at an earlier age. The sIgE sensitization was positively associated with male sex. The sIgE seroprevalence was higher in participants with both AR and AC (ARC) than in participants with either AR or AC. Allergic predisposition and sIgE sensitization increased the risk of the diseases, while farm upbringing was associated with reduced prevalence of ARC, however, only in sIgE sensitized participants.ConclusionBirth year, childhood residence, sIgE sensitization, and allergic predisposition were associated with asthma, AR, and AC prevalence. Individuals with self‐reported ARC represent a primarily sIgE‐positive phenotype, while those with either AR or AC represent more diverse phenotypes. 相似文献
83.
A.C. van Dijk M.T.B. Truijman B. Hussain T. Zadi G. Saiedie A.A.J. de Rotte M.I. Liem A.F.W. van der Steen M.J.A.P. Daemen P.J. Koudstaal P.J. Nederkoorn J. Hendrikse M.E. Kooi A. van der Lugt 《AJNR. American journal of neuroradiology》2015,36(11):2127
BACKGROUND AND PURPOSE:An important characteristic of vulnerable plaque, intraplaque hemorrhage, may predict plaque rupture. Plaque rupture can be visible on noninvasive imaging as a disruption of the plaque surface. We investigated the association between intraplaque hemorrhage and disruption of the plaque surface.MATERIALS AND METHODS:We selected the first 100 patients of the Plaque At RISK study, an ongoing prospective noninvasive plaque imaging study in patients with mild-to-moderate atherosclerotic lesions in the carotid artery. In carotid artery plaques, disruption of the plaque surface (defined as ulcerated plaques and/or fissured fibrous cap) and intraplaque hemorrhage were assessed by using MDCTA and 3T MR imaging, respectively. We used a χ2 test and multivariable logistic regression to assess the association between intraplaque hemorrhage and disrupted plaque surface.RESULTS:One hundred forty-nine carotid arteries in 78 patients could be used for the current analyses. Intraplaque hemorrhage and plaque ulcerations were more prevalent in symptomatic compared with contralateral vessels (hemorrhage, 38% versus 11%; P < .001; and ulcerations, 27% versus 7%; P = .001). Fissured fibrous cap was more prevalent in symptomatic compared with contralateral vessels (13% versus 4%; P = .06). After adjustment for age, sex, diabetes mellitus, and degree of stenosis, intraplaque hemorrhage was associated with disrupted plaque surface (OR, 3.13; 95% CI, 1.25–7.84) in all vessels.CONCLUSIONS:Intraplaque hemorrhage is associated with disruption of the plaque surface in patients with a carotid artery stenosis of <70%. Serial studies are needed to investigate whether intraplaque hemorrhage indeed increases the risk of plaque rupture and subsequent ischemic stroke during follow-up.The need to identify patients with mild-to-moderate carotid artery stenosis and an increased stroke risk who might benefit from surgical treatment has shifted research interest from assessment of the degree of carotid stenosis to assessment of vulnerable plaque characteristics.1 Vulnerable plaques are atherosclerotic plaques more prone to rupture and are associated with a higher risk for thromboembolism and ischemic stroke.2,3 Intraplaque hemorrhage is an important characteristic of the vulnerable plaque.4 Prevalence of intraplaque hemorrhage has been shown to be higher in symptomatic than in asymptomatic lesions.5 Moreover, the presence of intraplaque hemorrhage in carotid artery disease is associated with an increased risk of cerebral ischemic events.6–8The pathophysiologic mechanism leading to intraplaque hemorrhage is a topic of debate. However, a common viewpoint is that small leaky neovessels in the atherosclerotic plaques are a likely source of intraplaque hemorrhage.5,9,10 The presence of intraplaque hemorrhage is thought to initiate several biologic processes like phagocytosis and local inflammation, leading to the release of proteolytic enzymes, deposition of free cholesterol and subsequently plaque growth, plaque destabilization, and possible plaque rupture.5,9–12 Plaque rupture can be visible on imaging as a disruption of the atherosclerotic plaque surface (plaque ulceration and/or a fissured fibrous cap).13,14 A previous study reported that plaque ulceration on CTA was useful for the prediction of intraplaque hemorrhage on MR imaging in a broad group of symptomatic patients referred for carotid artery imaging.15 Ulcerated plaques themselves are independently associated with an increased risk of ipsilateral ischemic events as well.16,17The aim of the current study was to investigate the association between intraplaque hemorrhage, as assessed on MR imaging, and disruption of the plaque surface, assessed on MDCTA, in symptomatic patients with a carotid artery stenosis of <70%. 相似文献
84.
C. Rothe C. Steen‐Hansen M. H. Madsen L. H. Lundstrøm R. Heimburger K. E. Jensen K. H. W. Lange 《Anaesthesia》2015,70(7):791-796
We have developed a peripheral nerve catheter, attached to a needle, which works like an adjustable suture. We used in‐plane ultrasound guidance to place 45 catheters close to the femoral, saphenous, sciatic and distal tibial nerves in cadaver legs. We displaced catheters after their initial placement and then attempted to return them to their original positions. We used ultrasound to evaluate the initial and secondary catheter placements and the spread of injectate around the nerves. In 10 cases, we confirmed catheter position by magnetic resonance imaging. We judged 43/45 initial placements successful and 42/43 secondary placements successful by ultrasound, confirmed in 10/10 cases by magnetic resonance imaging. 相似文献
85.
Resveratrol reduces the levels of circulating androgen precursors but has no effect on,testosterone, dihydrotestosterone,PSA levels or prostate volume. A 4‐month randomised trial in middle‐aged men
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86.
The long‐term influence of repetitive cellular cardiac rejections on left ventricular longitudinal myocardial deformation in heart transplant recipients
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Tor Skibsted Clemmensen Brian Bridal Løgstrup Hans Eiskjær Søren Høyer Steen Hvitfeldt Poulsen 《Transplant international》2015,28(4):475-484
The aim of the study was to evaluate the long‐term influence of repeated acute cellular rejections on left ventricular longitudinal deformation in heart transplantation (HTX) patients. One hundred and seventy‐eight HTX patients were included in the study. Rejections were classified according to the International Society of Heart and Lung Transplantation (ISHLT) classification (0R–3R). Patients were divided into three groups according to rejection scores (RSs). Group 1: <50% of biopsies with 1R rejection and no ≥2R rejections; Group 2: ≥50% of biopsies with 1R rejection or one biopsy with ≥2R rejection; Group 3: ≥Two biopsies with ≥2R rejections. All patients had a comprehensive echocardiographic examination and coronary angiography. We found significantly decreasing global longitudinal strain (GLS) comparing to rejection groups (GLS group 1: ?16.8 ± 2.4 (%); GLS group 2: ?15.9 ± 3.3 (%); GLS group 3: ?14.5 ± 2.9 (%), P = 0.0003). After excluding patients with LVEF < 50% or vasculopathy, GLS was still significantly reduced according to RS groups (P = 0.0096). Total number of 1R and 2R rejections correlated significant to GLS in a linear regression model. In contrast, we found fractional shortening and LVEF to be unaffected by repeated rejections. In conclusion, repeated cardiac rejections lead to impaired graft function as detected by decreasing magnitude of GLS. In contrast, traditional systolic graft function surveillance by LVEF did not correlate to rejection burden. 相似文献
87.
Robert F Storey Steen Husted Robert A Harrington Stanley Heptinstall Robert G Wilcox Gary Peters Mark Wickens H?kan Emanuelsson Paul Gurbel Peer Grande Christopher P Cannon 《Journal of the American College of Cardiology》2007,50(19):1852-1856
OBJECTIVES: In a substudy of DISPERSE (Dose confIrmation Study assessing anti-Platelet Effects of AZD6140 vs. clopidogRel in non-ST-segment Elevation myocardial infarction)-2, we compared the antiplatelet effects of AZD6140 and clopidogrel and assessed the effects of AZD6140 in clopidogrel-pretreated patients. BACKGROUND: Clopidogrel, in combination with aspirin, reduces cardiovascular events in patients with acute coronary syndromes (ACS). However, patients with poor inhibition of platelet aggregation with clopidogrel may be less well protected. AZD6140 is a reversible oral P2Y(12) receptor antagonist that has been studied in ACS patients in comparison with clopidogrel (DISPERSE-2 study). METHODS: Patients were randomized to receive either AZD6140 90 mg twice a day, AZD6140 180 mg twice a day, or clopidogrel 75 mg once a day for up to 12 weeks in a double-blind, double-dummy design. One-half the patients allocated AZD6140 received a 270-mg loading dose. Patients randomized to receive clopidogrel were given a 300-mg loading dose unless they had already been treated with clopidogrel. Adenosine diphosphate-induced platelet aggregation was assessed by optical aggregometry on day 1 and at 4-week intervals. RESULTS: AZD6140 inhibited platelet aggregation in a dose-dependent fashion and both doses achieved greater levels of inhibition than clopidogrel (e.g., 4 weeks, 4-h postdose [mean (+/-SD)]: clopidogrel 64% [+/-22%], AZD6140 90 mg 79% [+/-22%], AZD6140 180 mg 95% [+/-8%]. AZD6140 also produced further suppression of platelet aggregation in patients previously treated with clopidogrel. CONCLUSIONS: AZD6140 exhibited greater mean inhibition of platelet aggregation than a standard regimen of clopidogrel in ACS patients. In addition, AZD6140 further suppressed platelet aggregation in clopidogrel pretreated patients. 相似文献
88.
Mari Botti BA GDACP DipN RN MRCNA Betty Williamson RN CCRN Kate Steen RN CCRN B.App.Sci. MRCNA Jo McTaggart RN CCRN Elizabeth Reid RN CCRN 《Heart & lung : the journal of critical care》1998,27(6):360
OBJECTIVES: To determine the effectiveness of pressure bandaging in reducing bleeding and bruising in patients undergoing coronary angiography and to investigate the contribution that pressure bandages make to patient discomfort after angiography.DESIGN: A prospective multicenter, randomized study.SETTING: Three university hospitals in Melbourne, Australia.PATIENTS: One thousand seventy-five patients undergoing coronary angiography were randomized to receive a pressure bandage (N = 556) or no bandage (N = 519) after manual compression of the right femoral artery puncture site.RESULTS: Patients without pressure bandages had a higher incidence of bleeding (P < 0.05) and bled earlier (mean 2.4 hours; SD 3.6 hours) after catheter removal (P < 0.001) than patients with bandages (mean 5.3 hours; SD 3.8 hours). The incidence of bleeding in patients without pressure bandages was 6.7%. The incidence and extent of bruising was the same for both groups. Patients with pressure bandages experienced a higher incidence of back (P < 0.05), groin (P < 0.001), and leg pain (P < 0.001), nausea (P < 0.05), and urinary difficulty (P < 0.01).CONCLUSIONS: In view of the associated increase in patient discomfort and the delay in time of onset of bleeding, pressure bandages should not be used routinely in the management of patients after coronary angiography, especially in the context of early discharge from the hospital. 相似文献
89.
Magnus Edner Vernon V. S. Bonarjee Dennis W. T. Nilsen Jens Berning Steen Carstensen Kenneth Caidahl 《Clinical cardiology》1996,19(7):543-548
Background and hypothesis: Although the angiotensin-converting enzyme inhibitor enalapril has recently been shown to reduce mortality and the need for hospitalization in patients with left ventricular dysfunction and congestive heart failure, this drug was found to have no significant impact on short-term mortality after acute myocardial infarction (AMI) in the CONSENSUS II trial. The effect of enalapril initiated early after AMI on clinical and echocardiographic determinants of left ventricular (LV) function was studied in a subset of patients from CONSENSUS II Methods: Symptoms and signs of heart failure were classified as NYHA and dyspnea classes. Echocardiography included LV end-systolic volumes (ESV) and end-diastolic volumes (EDV), as well as ejection fraction (EF). wall motion index (WMI), and mitral flow indices. In all, 428 patients were included and followed for an average of 5.1 months by serial examinations, starting 2–5 days after myocardial infarction (MI) and repeated after 1 month and at the completion of the study. Results: There was no beneficial effect of enalapril on clinically determined function. Changes (i.e. changes in NYHA class) in the functional status remained correlated with changes in echocardiographic determinants throughout the study in patients belonging to the placebo group: EDV index (r=0.36, p = 0.002, ESV index (r = 0.49, p < 0.001), EF (r = -0.41, p < 0.001), and WMI (r=0.29, p = 0.008). In a stepwise logistic regression model, the best baseline parameters to predict NYHA class at final visit in all patients were age (p = 0.014) and ESV index (p = 0.001). Conclusion: Enalapril treatment for an average period of 5.1 months following MI resulted in no clinically significant beneficial effects on NYHA and dyspnea class. Changes in clinical function class were correlated with changes in echocardiographic determinants in placebo-treated patients, but not in patients given enalapril. 相似文献
90.
Shiwen Yuan Per Blomström Steen Pehrson S Bertil Olsson 《The International Journal of Cardiac Imaging》1991,7(3-4):193-205
Noninvasive localization of the accessory pathway (AP) in patients with the Wolff-Parkinson-White syndrome and of the site of origin of ventricular tachycardia (VT) is reviewed. 12-lead electrocardiography (ECG) is the most readily available method for localization of both the AP and the site of VT origin. Many published ECG criteria are introduced. The application of body surface potential mapping, vectocardiography, nuclear phase imaging, echocardiography, computed tomography, nuclear magnetic resonance, and signal-averaged ECG in the localization of these arrhythmogenic substrates is also described. We believe that ECG is the most sensitive noninvasive method for AP localization as well as being convenient and simple; it may be used as the only noninvasive method for the initial evaluation. The left lateral AP, which occurs with an incidence of more than 40%, could be localized preoperatively by noninvasive methods only. For localization of the site of VT origin, none of the noninvasive methods is accurate enough for guiding the surgical and catheter-mediated ablative therapies so far.Abbreviations AP
accessory pathway
- ARVD
arrhythmogenic right ventricular dysplasia
- BSPM
body surface potential mapping
- LFW
left free wall
- LAW
left anterior wall
- LLW
left lateral wall
- LPW
left posterior wall
- LPS
left posteroseptal
- NMR
nuclear magnetic resonance
- PS
posteroseptal
- RFW
right free wall
- RAS
right anteroseptal
- RAW
right anterior wall
- RLW
right lateral wall
- RPW
right posterior wall
- RPS
right posteroseptal
- VPB
ventricular premature beats 相似文献