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151.
Mortality and rate of stroke or embolism in atrial fibrillation during long-term follow-up in the embolism in left atrial thrombi (ELAT) study 总被引:3,自引:0,他引:3
Stöllberger C Chnupa P Abzieher C Länger T Finsterer J Klem I Hartl E Wehinger C Schneider B 《Clinical cardiology》2004,27(1):40-46
BACKGROUND: Patients with atrial fibrillation (AF) have a higher mortality and risk of stroke/embolism than patients with sinus rhythm. HYPOTHESIS: The aim of the study was to assess the association of clinical and echocardiographic characteristics with mortality and stroke/embolism and the use of antithrombotic medication in the year 2000 in patients who participated 1990-1995 in the Embolism in Left Atrial Thrombi (ELAT) study. METHODS: The study included 409 outpatients with nonrheumatic AF (62 +/- 12 years, 36% women, 39% intermittent AF). Patients with thrombi received anticoagulation, patients without thrombi aspirin until follow-up in 1995; thereafter, anticoagulation according to clinical risk factors was recommended. Primary events were death and secondary events were stroke/embolism. All patients were contacted during the year 2000. RESULTS: Mean follow-up was 102 months. Mortality was 4%/year; the cause of death was cardiac (n = 84), fatal stroke (n = 26), malignancy (n = 23), sepsis (n = 5), and unknown (n = 24). Multivariate analysis identified age (p < 0.0001), heart failure (p = 0.0013), and reduced left ventricular systolic function (p = 0.0353) as predictors of mortality. Stroke/embolism occurred in 83 patients, with a rate of 3%/year. Multivariate analysis identified age (p = 0.0006) and previous stroke (p = 0.0454) as predictors of stroke/embolism. In the year 2000, 51 (21%) of the 247 surviving patients received no antithrombotic medication, 88 received (36%) oral anticoagulants, 102 (41%) acetylsalicylic acid, and 6 (2%) low-molecular heparin. CONCLUSIONS: Therapy for heart failure and oral anticoagulation in AF should be seriously considered, especially in elderly patients and in those with previous stroke. 相似文献
152.
Schuch Felipe Barreto Bulzing Rugero A. Meyer Jacob López-Sánchez Guillermo F. Grabovac Igor Willeit Peter Vancampfort Davy Caperchione Cristina M. Sadarangani Kabir P. Werneck André O. Ward Philip B. Tully Mark Smith Lee 《Sport Sciences for Health》2022,18(1):155-163
Sport Sciences for Health - The COVID-19 pandemic imposed major changes on daily-life routine worldwide. To the best of our knowledge, no study quantified the changes on moderate to vigorous... 相似文献
153.
The main purpose of this study was to determine if differences in life spans of two different strains of mice are associated with the thiol redox state of their tissues and mitochondria. A comparison, based on amounts of reduced and oxidized glutathione (GSH, GSSG) and reactive protein thiols, was made between short-lived SAM (P8) mice and the longer-lived C57BL/6 mice at 13 months of age. The average life span of the latter mouse strain is approximately 48% longer than the former strain. Analyses of plasma, tissue homogenates and mitochondria of liver, kidney, heart, brain and skeletal muscle indicated that, in general, amounts of GSH and reactive protein sulfhydryls and GSH:GSSG ratios were lower and concentrations of GSSG were higher in the SAM than the C57BL/6 mice. Differences in the redox state between the two strains were more consistent and pronounced in skeletal muscle than in other tissues, and in mitochondria than in their respective tissue homogenates. Overall, the results support the view that the shorter-lived SAM mice exhibit a relatively higher level of oxidative stress than the longer-lived C57BL/6 mice, which is consistent with the predictions of the oxidative stress hypothesis of aging. Intra-species comparisons may be useful for the identification of biochemical characteristics associated with the variations in life spans. 相似文献
154.
155.
Han W. Kim Wolfgang G. Rehwald Elizabeth R. Jenista David C. Wendell Peter Filev Lowie van Assche Christoph J. Jensen Michele A. Parker Enn-ling Chen Anna Lisa C. Crowley Igor Klem Robert M. Judd Raymond J. Kim 《JACC: Cardiovascular Imaging》2018,11(12):1758-1769
Objectives
This study introduced and validated a novel flow-independent delayed enhancement technique that shows hyperenhanced myocardium while simultaneously suppressing blood-pool signal.Background
The diagnosis and assessment of myocardial infarction (MI) is crucial in determining clinical management and prognosis. Although delayed enhancement cardiac magnetic resonance (DE-CMR) is an in vivo reference standard for imaging MI, an important limitation is poor delineation between hyperenhanced myocardium and bright LV cavity blood-pool, which may cause many infarcts to become invisible.Methods
A canine model with pathology as the reference standard was used for validation (n = 22). Patients with MI and normal controls were studied to ascertain clinical performance (n = 31).Results
In canines, the flow-independent dark-blood delayed enhancement (FIDDLE) technique was superior to conventional DE-CMR for the detection of MI, with higher sensitivity (96% vs. 85%, respectively; p = 0.002) and accuracy (95% vs. 87%, respectively; p = 0.01) and with similar specificity (92% vs, 92%, respectively; p = 1.0). In infarcts that were identified by both techniques, the entire length of the endocardial border between infarcted myocardium and adjacent blood-pool was visualized in 33% for DE-CMR compared with 100% for FIDDLE. There was better agreement for FIDDLE-measured infarct size than for DE-CMR infarct size (95% limits-of-agreement, 2.1% vs. 5.5%, respectively; p < 0.0001). In patients, findings were similar. FIDDLE demonstrated higher accuracy for diagnosis of MI than DE-CMR (100% [95% confidence interval [CI]: 89% to 100%] vs. 84% [95% CI: 66% to 95%], respectively; p = 0.03).Conclusions
The study introduced and validated a novel CMR technique that improves the discrimination of the border between infarcted myocardium and adjacent blood-pool. This dark-blood technique provides diagnostic performance that is superior to that of the current in vivo reference standard for the imaging diagnosis of MI. 相似文献156.
Controlling the size of nanoscale toroidal DNA condensates with static curvature and ionic strength
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Conwell CC Vilfan ID Hud NV 《Proceedings of the National Academy of Sciences of the United States of America》2003,100(16):9296-9301
The process of DNA condensation into nanometer-scale particles has direct relevance to several fields, including cell biology, virology, and gene delivery for therapeutic purposes. DNA condensation has also attracted the attention of polymer physicists, as the collapse of DNA molecules from solution into well defined particles represents an exquisite example of a polymer phase transition. Here we present a quantitative study of DNA toroids formed by condensation of 3 kb DNA with hexammine cobalt (III). The presence or absence of static loops within this DNA molecule demonstrates the effect of nucleation loop size on toroid dimensions and that nucleation is principally decoupled from toroid growth. A comparison of DNA condensates formed at low ionic strength with those formed in the presence of additional salts (NaCl or MgCl2) shows that toroid thickness is a salt-dependant phenomenon. Together, these results have allowed the development of models for DNA toroid formation in which the size of the nucleation loop directly influences the diameter of the fully formed toroid, whereas solution conditions govern toroid thickness. The data presented illustrate the potential that exists for controlling DNA toroid dimensions. Furthermore, this study provides a set of data that should prove useful as a test for theoretical models of DNA condensation. 相似文献
157.
Adenosine receptors in regulation of dendritic cell differentiation and function 总被引:1,自引:0,他引:1
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Novitskiy SV Ryzhov S Zaynagetdinov R Goldstein AE Huang Y Tikhomirov OY Blackburn MR Biaggioni I Carbone DP Feoktistov I Dikov MM 《Blood》2008,112(5):1822-1831
Differentiation of functional dendritic cells (DCs) critically depends on the microenvironment. DCs differentiate in hypoxic tumor sites and inflamed or damaged tissue. Because local concentrations of adenosine reach high physiologically relevant levels in these conditions, we assessed the expression of adenosine receptors and the effect of their activation on differentiation of human monocytes and mouse peritoneal macrophages and hematopoietic progenitor cells (HPCs) into myeloid DCs. Stimulation of adenosine receptors skews DC differentiation toward a distinct cell population characterized by expression of both DC and monocyte/macrophage cell surface markers. Pharmacologic analysis and experiments with cells from A(2B) adenosine receptor knockout mice identified A(2B) receptor as the mediator of adenosine effects on DCs. Unlike normal myeloid DCs, adenosine-differentiated DCs have impaired allostimulatory activity and express high levels of angiogenic, pro-inflammatory, immune suppressor, and tolerogenic factors, including VEGF, IL-8, IL-6, IL-10, COX-2, TGF-beta, and IDO. They promoted tumor growth if injected into tumors implanted in mice. Using adenosine desaminase knockout animals, we showed that DCs with proangiogenic phenotype are highly abundant under conditions associated with elevated levels of extracellular adenosine in vivo. Adenosine signaling through A(2B) receptor is an important factor of aberrant DC differentiation and generation of tolerogenic, angiogenic, and proinflammatory cells. 相似文献
158.
Dulciene Maria Magalh?es Queiroz Mayuko Saito Gifone Aguiar Rocha Andreia Maria Camargos Rocha Fabrício Freire Melo William Checkley Lúcia Libanez Bessa C. Braga Igor Sim?es Silva Robert H. Gilman Jean E. Crabtree 《Journal of clinical microbiology》2013,51(11):3735-3740
Accurate noninvasive tests for diagnosing Helicobacter pylori infection in very young children are strongly required. We investigated the agreement between the [13C]urea breath test ([13C]UBT) and a monoclonal ELISA (HpSA) for detection of H. pylori antigen in stool. From October 2007 to July 2011, we enrolled 414 infants (123 from Brazil and 291 from Peru) of ages 6 to 30 months. Breath and stool samples were obtained at intervals of at least 3 months from Brazilian (n = 415) and Peruvian (n = 908) infants. [13C]UBT and stool test results concurred with each other in 1,255 (94.86%) cases (kappa coefficient = 0.90; 95% confidence interval [CI] = 0.87 to 0.92). In the H. pylori-positive group, delta-over-baseline (DOB) and optical density (OD) values were positively correlated (r = 0.62; P < 0.001). The positivity of the tests was higher (P < 0.001; odds ratio [OR] = 6.01; 95% CI = 4.50 to 8.04) in Peru (546/878; 62.2%) than in Brazil (81/377; 21.5%) and increased with increasing age in Brazil (P = 0.02), whereas in Peru it decreased with increasing age (P < 0.001). The disagreement between the test results was associated with birth in Brazil and female gender but not with age and diarrhea. Our results suggest that both [13C]UBT and the stool monoclonal test are reliable for diagnosing H. pylori infection in very young children, which will facilitate robust epidemiological studies in infants and toddlers. 相似文献
159.
Igor A. Sobenin Vasily P. Karagodin Alexandra А. Melnichenko Yuri V. Bobryshev Alexander N. Orekhov 《Journal of clinical immunology》2013,33(2):489-495
Recently, it has been shown that increased level of LDL-containing circulating immune complexes (LDL-CIC) possess high diagnostic significance in clinically manifested atherosclerosis, but little is known about its diagnostic and prognostic significance in early atherosclerosis. Two-years prospective study was performed in 98 asymptomatic men aged 40–74. The rate of atherosclerosis progression was estimated by high-resolution B-mode ultrasonography as the increase in intima-media thickness (IMT) of common carotid arteries. The patients with elevated baseline levels of LDL-CIC were characterized by significantly higher levels of total and LDL cholesterol as well as significantly increased mean IMT of common carotid arteries. Among all baseline lipid parameters, only LDL-CIC and LDL cholesterol were contingent with the extent of early carotid atherosclerosis (p?=?0.042 and p?=?0.049, respectively) and had the highest levels of relative risk and odds ratio. During the follow up, significant IMT increase was registered in 53.1 % (n?=?52) patients, IMT significant reduction was observed in 21.4 % (n?=?21) patients. The increased levels of LDL-CIC, total serum cholesterol and LDL cholesterol had similar prognostic significance with the respect of atherosclerosis progression. The normal level of LDL-CIC (below than 16.0 μg/ml) was the only lipid parameter that predicted the absence of carotid atherosclerosis progression for two following years at prognostic value of 78.3 %. The results of the study allow assuming that LDL-CIC level may be employed not only as a marker of early atherosclerosis, but also has a sufficient prognostic value for clinical implications. 相似文献
160.
Neelang Parghi Lakshmi Chennapragada Shira Barzilay Saskia Newkirk Brian Ahmedani Benjamin Lok Igor Galynker 《International journal of methods in psychiatric research》2021,30(1):e1863
ObjectiveThis study explores the prediction of near‐term suicidal behavior using machine learning (ML) analyses of the Suicide Crisis Inventory (SCI), which measures the Suicide Crisis Syndrome, a presuicidal mental state.MethodsSCI data were collected from high‐risk psychiatric inpatients (N = 591) grouped based on their short‐term suicidal behavior, that is, those who attempted suicide between intake and 1‐month follow‐up dates (N = 20) and those who did not (N = 571). Data were analyzed using three predictive algorithms (logistic regression, random forest, and gradient boosting) and three sampling approaches (split sample, Synthetic minority oversampling technique, and enhanced bootstrap).ResultsThe enhanced bootstrap approach considerably outperformed the other sampling approaches, with random forest (98.0% precision; 33.9% recall; 71.0% Area under the precision‐recall curve [AUPRC]; and 87.8% Area under the receiver operating characteristic [AUROC]) and gradient boosting (94.0% precision; 48.9% recall; 70.5% AUPRC; and 89.4% AUROC) algorithms performing best in predicting positive cases of near‐term suicidal behavior using this dataset.ConclusionsML can be useful in analyzing data from psychometric scales, such as the SCI, and for predicting near‐term suicidal behavior. However, in cases such as the current analysis where the data are highly imbalanced, the optimal method of measuring performance must be carefully considered and selected. 相似文献