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991.
992.
Mayra Guerrero Amit Pursnani Akhil Narang Michael Salinger Dee Dee Wang Mackram Eleid Susheel K. Kodali Isaac George Lowell Satler Ron Waksman Christopher U. Meduri Vivek Rajagopal Ignacio Inglessis Igor Palacios Mark Reisman Marvin H. Eng Hyde M. Russell Ashish Pershad Charanjit Rihal 《JACC: Cardiovascular Interventions》2021,14(8):859-872
ObjectivesThe aim of this study was to assess 1-year clinical outcomes among high-risk patients with failed surgical mitral bioprostheses who underwent transseptal mitral valve-in-valve (MViV) with the SAPIEN 3 aortic transcatheter heart valve (THV) in the MITRAL (Mitral Implantation of Transcatheter Valves) trial.BackgroundThe MITRAL trial is the first prospective study evaluating transseptal MViV with the SAPIEN 3 aortic THV in high-risk patients with failed surgical mitral bioprostheses.MethodsHigh-risk patients with symptomatic moderate to severe or severe mitral regurgitation (MR) or severe mitral stenosis due to failed surgical mitral bioprostheses were prospectively enrolled. The primary safety endpoint was technical success. The primary THV performance endpoint was absence of MR grade ≥2+ or mean mitral valve gradient ≥10 mm Hg (30 days and 1 year). Secondary endpoints included procedural success and all-cause mortality (30 days and 1 year).ResultsThirty patients were enrolled between July 2016 and October 2017 (median age 77.5 years [interquartile range (IQR): 70.3 to 82.8 years], 63.3% women, median Society of Thoracic Surgeons score 9.4% [IQR: 5.8% to 12.0%], 80% in New York Heart Association functional class III or IV). The technical success rate was 100%. The primary performance endpoint in survivors was achieved in 96.6% (28 of 29) at 30 days and 82.8% (24 of 29) at 1 year. Thirty-day all-cause mortality was 3.3% and was unchanged at 1 year. The only death was due to airway obstruction after swallowing several pills simultaneously 29 days post-MViV. At 1-year follow-up, 89.3% of patients were in New York Heart Association functional class I or II, the median mean mitral valve gradient was 6.6 mm Hg (interquartile range: 5.5 to 8.9 mm Hg), and all patients had MR grade ≤1+.ConclusionsTransseptal MViV in high-risk patients was associated with 100% technical success, low procedural complication rates, and very low mortality at 1 year. The vast majority of patients experienced significant symptom alleviation, and THV performance remained stable at 1 year. 相似文献
993.
A Cohort Study of Anticholinergic Medication Burden and Incident Dementia and Stroke in Older Adults
Jessica E. Lockery Jonathan C. Broder Joanne Ryan Ashley C. Stewart Robyn L. Woods Trevor T.-J. Chong Geoffrey C. Cloud Anne Murray Jason D. Rigby Raj Shah Elsdon Storey Stephanie A. Ward Rory Wolfe Christopher M. Reid Taya A. Collyer Michael E. Ernst 《Journal of general internal medicine》2021,36(6):1629
BackgroundAnticholinergic medications may increase risk of dementia and stroke, but prospective studies in healthy older people are lacking.ObjectiveCompare risk of incident dementia and stroke by anticholinergic burden among initially healthy older people.DesignProspective cohort study.SettingPrimary care (Australia and USA).Participants19,114 community-dwelling participants recruited for the ASPREE trial, aged 70+ years (65+ if US minorities) without major cardiovascular disease, dementia diagnosis, or Modified Mini-Mental State Examination score below 78/100.MeasurementsBaseline anticholinergic exposure was calculated using the Anticholinergic Cognitive Burden (ACB) score. Dementia was adjudicated using Diagnostic and Statistical Manual of Mental Disorders volume IV criteria, and stroke using the World Health Organization definition.ResultsAt baseline, 15,000 participants (79%) had an ACB score of zero, 2930 (15%) a score of 1–2, and 1184 (6%) a score of ≥ 3 (indicating higher burden). After a median follow-up of 4.7 years and adjusting for baseline covariates, a baseline ACB score of ≥ 3 was associated with increased risk of ischemic stroke (adjusted HR 1.58, 95% CI 1.06, 2.35), or dementia (adjusted HR 1.36, 95% CI 1.01, 1.82), especially of mixed etiology (adjusted HR 1.53, 95% CI 1.06, 2.21). Results were similar for those exposed to moderate/highly anticholinergic medications.LimitationsResidual confounding and reverse causality are possible. Assessment of dose or duration was not possible.ConclusionsHigh anticholinergic burden in initially healthy older people was associated with increased risk of incident dementia and ischemic stroke. A vascular effect may underlie this association. These findings highlight the importance of minimizing anticholinergic exposure in healthy older people.Supplementary InformationThe online version contains supplementary material available at 10.1007/s11606-020-06550-2.KEY WORDS: anticholinergic burden, dementia, stroke, potentially inappropriate medication 相似文献
994.
David L. Leverenz Christopher Henderson Ankoor Shah 《Current allergy and asthma reports》2018,18(8):40
Purpose of Review
The goal of this review is to provide the reader with an updated summary of the cutaneous manifestations of systemic sarcoidosis, with a particular emphasis on the predilection of sarcoidosis for scars, tattoos, and other areas of traumatized skin.Recent Findings
While the mechanism underlying the propensity for traumatized skin to develop sarcoidosis lesions remains unclear, several theories have been proposed including the idea that cutaneous sarcoidosis represents an exuberant, antigen-driven foreign-body response, as well as the theory that traumatized skin represents an immunocompromised district with altered local immune trafficking and neural signaling.Summary
In this review, we present two cases in which the development of cutaneous lesions in scars and tattoos was integral to the diagnosis of systemic sarcoidosis. We then review the various cutaneous manifestations of systemic sarcoidosis, the clinical characteristics and differential diagnosis of scar and tattoo sarcoidosis, the proposed mechanism by which traumatized skin is prone to developing sarcoidosis lesions, and current treatments for cutaneous sarcoidosis.995.
El-Ahdab F Benjamin DK Wang A Cabell CH Chu VH Stryjewski ME Corey GR Sexton DJ Reller LB Fowler VG 《The American journal of medicine》2005,118(3):225-229
PURPOSE: Staphylococcus aureus is a common cause of bacteremia and of native valve infective endocarditis. However, the risk of endocarditis in patients with a prosthetic valve who develop S. aureus bacteremia is unclear. The aim of this study was to define the risk of prosthetic valve endocarditis in patients with S. aureus bacteremia. SUBJECTS AND METHODS: All patients with a prosthetic valve or ring who developed S. aureus bacteremia during the 94-month study period were prospectively evaluated. The modified Duke criteria were used for the diagnosis of endocarditis. Patients were followed up for 12 weeks after the initial diagnosis of S. aureus bacteremia. RESULTS: The overall rate of definite prosthetic valve endocarditis among the study patients was 26/51 (51%). The risk of endocarditis was similar in patients with late (>or=12 months after valve implantation) vs. early S. aureus bacteremia (<12 months after prosthetic valve implantation) (50% vs. 52%, P=1.0), mitral vs. aortic prostheses (62% vs. 48%, P=0.24), and mechanical vs. bioprosthetic valves (62% vs. 44%, P=0.29). The 12-week mortality was higher among patients with definite vs. possible endocarditis (62% vs. 28%, P=0.019). CONCLUSION: In this investigation, approximately half of all patients with prosthetic valves who developed S. aureus bacteremia had definite endocarditis. The risk of endocarditis was independent of the type, location, or age of the prosthetic valve. The mortality of prosthetic valve endocarditis is high. All patients with a prosthetic valve who develop S. aureus bacteremia should be aggressively screened and followed for endocarditis. 相似文献
996.
Min Yang Najdat B. Nazhat Xurong Jiang Stephen M. Kelsey David R. Blake Adrian C. Newland & Christopher J. Morris 《British journal of haematology》1996,95(2):339-344
It is becoming clear that adriamycin cytotoxicity may be mediated by semiquinone-free radicals derived from the drug itself and reactive oxygen species (ROS). Recent evidence supports the concept that low concentrations of ROS are able to stimulate cell proliferation, and, based on the observation that subtoxic concentrations of adriamycin can also induce cell proliferation, we hypothesize that low concentrations of adriamycin stimulate cell proliferation by a ROS generation mechanism. We have employed spin-trapping and electron spin resonance (ESR) spectroscopy to investigate the nature of the adriamycin-generated ROS. The spin trap 3,5-dibromo-4-nitrosobenzenesulphonate (DBNBS), which is oxidized in the presence of H2 O2 and peroxidase enzymes, was used to produce a characteristic three-line spectrum, and it was found that an identical spectrum was produced by human lymphoblastic leukaemic cells (CCRF-CEM cells) after exposure to adriamycin. We tested our hypothesis further by exposing CCRF-CEM cells to subtoxic concentrations of adriamycin (10−8 , 10−9 and 10−10 M ) and low concentrations of H2 O2 (10−8 , 10−9 and 10−10 M ) and subsequently monitored cell proliferation. We found that low concentrations of both adriamycin and H2 O2 significantly stimulate CCRF-CEM cell proliferation. We therefore conclude that subtoxic concentrations of adriamycin are likely to induce cell proliferation via an H2 O2 mediated mechanism. 相似文献
997.
Holtz TH Marum LH Mkandala C Chizani N Roberts JM Macheso A Parise ME Kachur SP 《Tropical medicine & international health : TM & IH》2002,7(3):220-230
OBJECTIVE: To evaluate the use of insecticide-treated bednets and the effectiveness of social marketing for their distribution. METHODS: Systematic cluster sample survey of 1080 households in 36 census enumeration areas across Blantyre district, Malawi, in February 2000. RESULTS: A total of 672 households had one or more children under 5. Bednet ownership was low (20.5% of households) overall, and significantly lower in rural areas than urban areas (6.4 vs. 29.8%, P=0.001). Only 3.3% of rural children under 5 had slept under a net the previous night, compared with 24.0% of urban children (P < 0.001). When asked why they did not own a net, nearly all (94.9%) caretakers in households without nets stated they had no money to buy them. In multivariate statistical models that controlled for the influence of house structure, urban vs. rural location, gender of the head of household, and the primary caretaker's education, rural children under 5 in households without nets experienced a statistically significant higher prevalence of malaria parasitaemia [RR (risk ratio) 4.9, 95% CI (confidence interval) 2.3-10.5] than children in households with at least one bednet. This was also true for urban children under 5 (RR 2.1, 95% CI 1.0-4.2, P=0.04). CONCLUSION: Social marketing approaches to promoting insecticide-treated nets in Blantyre District may have produced measurable health benefits for children in those households in which residents bought and used the products. Market-based approaches may take years to achieve high levels of coverage and may exaggerate inequities between urban and rural populations. 相似文献
998.
Hong Li Christopher Lelliott Karolina Ploj Martina Verolin-Johansson Björn Carlsson Erik Michaëlsson 《Metabolism: clinical and experimental》2008,57(12):1704-1710
Chronic inflammation and increased visceral adipose tissue (VAT) are key elements of the metabolic syndrome. Both are considered to play a pathogenic role in the development of liver steatosis and insulin resistance. The aim of the present study was to investigate the hypothesis that an inflamed intestine, induced both by diet and chemical irritation, could induce persistent inflammation in VAT. Female C57BL/6JOlaHsd mice were used. In study I, groups of mice (n = 6 per group) were given an obesity-inducing cafeteria diet (diet-induced obesity) or regular chow only (control) for 14 weeks. In study II, colitis in mice (n = 8) was induced by 3% dextran sulfate sodium in tap water for 5 days followed by 21 days of tap water alone. Healthy control mice (n = 8) had tap water only. At the end of the studies, all mice were killed; and blood and tissues were sampled and processed for analysis. Body weight of diet-induced obese mice was greatly increased, with evidence of systemic inflammation, insulin resistance, and liver steatosis. Tissue inflammation indexed by proinflammatory cytokine expression was recorded in liver, mesenteric fat, and proximal colon/distal ileum, but not in subcutaneous or perigonadal fat. In dextran sulfate sodium-induced colitis mice, mesenteric fat was even more inflamed than the colon, whereas a much milder inflammation was seen in liver and subcutaneous fat. The studies showed both diet- and colitis-initiated inflammation in mesenteric fat. Fat depots contiguous with intestine and their capacity for exaggerated inflammatory responses to conditions of impaired gut barrier function may account for the particularly pathogenic role of VAT in obesity-induced metabolic disorders. 相似文献
999.
Yung-Wei Chi Christopher J White T Cooper Woods Corey K Goldman 《Catheterization and cardiovascular interventions》2007,69(3):349-354
OBJECTIVE: To examine duplex ultrasound (US) criteria for carotid in-stent restenosis (ISR). BACKGROUND: Carotid artery stent (CAS) placement is an alternative to surgery for the treatment of carotid stenosis in high surgical risk patients. US is the primary method used to follow carotid stent patency. This study investigates US velocity measurements in carotid ISR. METHODS: Two hundred sixty consecutive patients with CAS placement from June 2000 to June 2004 were followed with serial US. ISR was determined by using the standard US velocity criteria for nonstented carotid artery using peak systolic velocity (PSV), end-diastolic velocity (EDV), and internal carotid artery to common carotid velocity ratio (ICA/CCA ratio). Patients suspected of having carotid ISR > or =50% by US, underwent invasive angiography with stenosis graded by NASCET criteria. Results were compared to patients with nonstented carotid artery stenosis using Two-tailed Student's t-test. RESULTS: PSV and ICA/CCA ratio increased to a greater degree in ISR. In 50-69% stenotic arteries, the mean ICA/CCA ratio was 2.76 +/- 0.7 in the ISR group compared to 2.04 +/- 0.3 in the nonstented carotid group (P < 0.05). In > or =70% stenotic arteries, there were increases in PSV (520 +/- 93 vs. 362 +/- 60, P < 0.05) and ICA/CCA ratio (7.58 +/- 2 vs. 4.51 +/- 1.3, P < 0.05) in ISR versus nonstented carotid arteries, respectively. CONCLUSION: PSV and ICA/CCA ratio in ISR increased to a greater extent for angiographic stenosis > or =50%. PSV 240 cm/sec and ICA/CCA ratio 2.45 are optimal thresholds for > or =50% ISR, and PSV 450 cm/sec and ICA/CCA ratio 4.3 are optimal thresholds for > or =70% ISR. 相似文献
1000.
Lars G Olsson Karl Swedberg Anique Ducharme Christopher B Granger Eric L Michelson John J V McMurray Margareta Puu Salim Yusuf Marc A Pfeffer 《Journal of the American College of Cardiology》2006,47(10):1997-2004
OBJECTIVES: We assessed the risk of adverse cardiovascular (CV) outcomes associated with atrial fibrillation (AF) in the Candesartan in Heart failure-Assessment of Reduction in Mortality and morbidity (CHARM) program, which enrolled patients with chronic heart failure (CHF) and a broad range of ejection fractions (EFs). BACKGROUND: Atrial fibrillation is associated with an increased risk of adverse CV outcomes in patients with CHF and reduced EF. The risk of AF in patients with CHF and preserved left ventricular ejection fraction (PEF) is unknown. METHODS: A total of 7,599 patients with symptomatic CHF were randomized to candesartan or placebo. Patients were divided by baseline EF (< or =40% or >40%) in low or preserved EF groups. Major outcomes were cardiovascular death or hospitalization for worsening heart failure, and all-cause mortality. Median follow-up was 37.7 months. RESULTS: A total of 670 (17%) patients in the low EF group and 478 (19%) in the PEF group had AF at baseline. Atrial fibrillation predicted a high risk of cardiovascular morbidity and mortality regardless of baseline EF. Patients with AF and low EF had the highest absolute risk for adverse CV outcomes. However, AF was associated with greater relative increased risk of the major outcomes in patients with PEF than in patients with low EF: hazard ratio 1.72 (95% confidence interval [CI] 1.45 to 2.06) versus 1.29 (95% CI 1.14 to 1.46), respectively. The same was true for the risk of all-cause mortality. Candesartan was associated with similar treatment effects regardless of baseline rhythm. CONCLUSIONS: Atrial fibrillation is associated with an increased risk of CV outcomes in patients with CHF and either reduced EF or PEF. Candesartan improved outcomes similarly regardless of baseline rhythm. 相似文献