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101.
Left ventricular diastolic dysfunction as a predictor of the first diagnosed nonvalvular atrial fibrillation in 840 elderly men and women 总被引:25,自引:0,他引:25
Tsang TS Gersh BJ Appleton CP Tajik AJ Barnes ME Bailey KR Oh JK Leibson C Montgomery SC Seward JB 《Journal of the American College of Cardiology》2002,40(9):1636-1644
OBJECTIVES: The objective of this study was to determine whether diastolic dysfunction is associated with increased risk of nonvalvular atrial fibrillation (NVAF) in older adults with no history of atrial arrhythmia. BACKGROUND: Few data exist regarding the relationship between diastolic function and NVAF. METHODS: The clinical and echocardiographic characteristics of patients age > or =65 years who had an echocardiogram performed between 1990 and 1998 were reviewed. Exclusion criteria were history of atrial arrhythmia, stroke, valvular or congenital heart disease, or pacemaker implantation. Patients were followed up in their medical records to the last clinical visit or death for documentation of first AF. RESULTS: Of 840 patients (39% men; mean [+/- SD] age, 75 +/- 7 years), 80 (9.5%) developed NVAF over a mean (+/- SD) follow-up of 4.1 +/- 2.7 years. Abnormal relaxation, pseudonormal, and restrictive left ventricular diastolic filling were associated with hazard ratios of 3.33 (95% confidence interval [CI], 1.5 to 7.4; p = 0.003), 4.84 (95% CI, 2.05 to 11.4; p < 0.001), and 5.26 (95% CI, 2.3 to 12.03; p < 0.001), respectively, when compared with normal diastolic function. After a number of adjustments, diastolic function profile remained incremental to history of congestive heart failure and previous myocardial infarction for prediction of NVAF. Age-adjusted Kaplan-Meier five-year risks of NVAF were 1%, 12%, 14%, and 21% for normal, abnormal relaxation, pseudonormal, and restrictive diastolic filling, respectively. CONCLUSIONS; The presence and severity of diastolic dysfunction are independently predictive of first documented NVAF in the elderly. 相似文献
102.
103.
Tarciso A. F. Velho Peter V. Lovell Samantha R. Friedrich Christopher R. Olson Joshua Miles Paul A. Mueller Hagai Tavori Sergio Fazio Carlos Lois Claudio V. Mello 《Proceedings of the National Academy of Sciences of the United States of America》2021,118(18)
The low-density lipoprotein receptor (LDLR) is key to cellular cholesterol uptake and is also the main receptor for the vesicular stomatitis virus glycoprotein (VSV G). Here we show that in songbirds LDLR is highly divergent and lacks domains critical for ligand binding and cellular trafficking, inconsistent with universal structure conservation and function across vertebrates. Linked to the LDLR functional domain loss, zebra finches show inefficient infectivity by lentiviruses (LVs) pseudotyped with VSV G, which can be rescued by the expression of human LDLR. Finches also show an atypical plasma lipid distribution that relies largely on high-density lipoprotein (HDL). These findings provide insights into the genetics and evolution of viral infectivity and cholesterol transport mechanisms in vertebrates. 相似文献
104.
Hardcastle Cheshire Hausman Hanna K. Kraft Jessica N. Albizu Alejandro O’Shea Andrew Boutzoukas Emanuel M. Evangelista Nicole D. Langer Kailey Van Etten Emily J. Bharadwaj Pradyumna K. Song Hyun Smith Samantha G. Porges Eric DeKosky Steven T. Hishaw Georg A. Wu Samuel S. Marsiske Michael Cohen Ronald Alexander Gene E. Woods Adam J. 《Age (Dordrecht, Netherlands)》2022,44(2):1011-1027
GeroScience - Prior randomized control trials have shown that cognitive training interventions resulted in improved proximal task performance, improved functioning of activities of daily living,... 相似文献
105.
Tixier Emily N. Verheyen Elijah Luo Yuying Grinspan Lauren Tal Du Charles H. Ungaro Ryan C. Walsh Samantha Grinspan Ari M. 《Digestive diseases and sciences》2022,67(3):978-988
Digestive Diseases and Sciences - Severe and fulminant Clostridioides difficile infection (CDI) is associated with significant morbidity and mortality. While fecal microbiota transplantation (FMT)... 相似文献
106.
Sleep characteristics as predictor variables of stress systems markers in insomnia disorder
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Samantha Floam Norah Simpson Emese Nemeth Jennifer Scott‐Sutherland Shiva Gautam Monika Haack 《Journal of sleep research》2015,24(3):296-304
This study investigates the extent to which sleep characteristics serve as predictor variables for inflammatory, hypothalamic–pituitary–adrenal and autonomic systems markers. Twenty‐nine participants with a diagnosis of insomnia disorder based on the Diagnostic Statistical Manual of Mental Disorders, Fifth Edition (age 25.3 ± 1.6 years, insomnia duration 6.6 ± 0.8 years) and 19 healthy control sleepers (age 25.4 ± 1.4 years) underwent a 2‐week at‐home evaluation keeping a sleep diary and wearing an actigraph, followed by a visit to the Research Center to measure blood pressure, and collect blood and urine samples. The actigraphy‐ and diary‐based variables of sleep duration, sleep‐onset latency, wake after sleep onset and sleep fragmentation/number of night‐time awakenings were averaged and entered as dependent variables in regression analyses. Composite scores were calculated for the autonomic (blood pressure, norepinephrine), inflammatory (monocyte counts, interleukin‐6, C‐reactive protein) and hypothalamic–pituitary–adrenal systems (cortisol), and used as predictor variables in regression models. Compared with controls, individuals with insomnia had a shorter sleep duration (P < 0.05), and a higher hypothalamic–pituitary–adrenal and inflammatory composite score (P < 0.05). The higher inflammatory score was mainly due to higher circulating monocytes (P < 0.05), rather than differences in interleukin‐6 or C‐reactive protein. In persistent insomnia disorder, cortisol is upregulated and associated with actigraphy‐ and diary‐based wake after sleep onset, suggesting that wake after sleep onset may serve as a marker to identify individuals at increased risks for disorders associated with a hyperactive hypothalamic–pituitary–adrenal system. The absence of autonomic and pro‐inflammatory changes (interleukin‐6, C‐reactive protein), despite a substantial decrease in actigraphic sleep duration, may relate to a higher resilience to the adverse biological consequences of insomnia in this young age group. 相似文献
107.
De Leon SF Thurston GD Ito K 《American journal of respiratory and critical care medicine》2003,167(8):1117-1123
Many time series studies have found that individuals with primary cardiac conditions were susceptible to the adverse effects associated with increased ambient particle levels. However, the mechanism(s) of these associations is not yet understood. In this study, we evaluate whether individuals with nonrespiratory primary causes of death who also had contributing respiratory causes listed on their death certificates were more affected by air pollution, as compared with those not having contributing respiratory conditions. Short-term associations between ambient particulate matter (10 microm or less in aerodynamic diameter) and mortality were modeled in New York City for the years 1985-1994. It was observed that among those 75 years or more, those with contributing respiratory disease had higher relative risks (95% confidence intervals) calculated per interquartile range, as compared with those without contributing respiratory disease for both circulatory deaths (relative risk = 1.066 [1.027-1.106] versus 1.022 [1.008-1.035]) and cancer deaths (relative risk = 1.129 [1.041-1.225] versus 1.025 [1.000-1.050]). However, this pattern of association was not observed for those who were less than 75 years old. The results of this study suggest that past studies may have underestimated the role of respiratory disease in pollution-mortality associations, especially among older adults. 相似文献
108.
An approach to fertility preservation in prepubertal and postpubertal females: A critical review of current literature
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109.
Borzi RM Mazzetti I Magagnoli G Paoletti S Uguccioni M Gatti R Orlandini G Cattini L Facchini A 《Arthritis and rheumatism》2002,46(12):3201-3211
OBJECTIVE: To evaluate the apoptotic effect of the chemokine growth-related oncogene alpha (GROalpha), which we recently reported to be up-regulated in osteoarthritis (OA) chondrocytes. Chondrocyte apoptosis is considered to be a major determinant of cartilage damage in OA, a disease resulting from the aberrant production of inflammatory mediators (cytokines and chemokines) and effectors (matrix metalloproteinases and reactive oxygen and nitrogen species) by chondrocytes. METHODS: We investigated the apoptotic effect of GROalpha on isolated human cells and on in vitro-cultured cartilage explants by conventional methods (morphology, detection of DNA fragmentation in situ and in solution, exposure of phosphatidylserine) and by analysis of "early" biochemical events (plasma membrane depolarization, activation of caspase 3, and phosphorylation of c-Jun N-terminal kinase/stress-activated protein kinase). RESULTS: We clearly demonstrated that GROalpha was able to initiate a series of morphologic, biochemical, and molecular changes that led to chondrocyte apoptosis. Moreover, we found that additional signals delivered from the extracellular matrix (ECM) were essential in the control of chondrocyte susceptibility to GROalpha-induced apoptosis, since cell death was detected only when cells were stimulated after reestablishment of their proper interactions with the ECM, or in cartilage explant samples with reduced ECM, as indicated by decreased Safranin O staining. CONCLUSION: GROalpha can induce apoptosis in articular chondrocytes, and the induction is dependent upon additional signals from the ECM. These findings are relevant to understanding the pathogenesis of OA, in view of the availability of the GROalpha chemokine in the joint space in the course of this rheumatic disease. 相似文献
110.