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101.
102.
Vijay R. Baral Gruschen R. Veldtman Arthur M. Yue Abdul Duke John M. Morgan 《Journal of interventional cardiac electrophysiology》2004,11(3):211-215
Ventricular tachycardia (VT) is rarely recognized in patients with congenitally corrected transposition of the great arteries (CCTGA). We describe a 48-year-old woman with CCTGA, systemic atrioventricular valve replacement for Ebsteinoid malformation of the valve, ventricular dysfunction and ventricular tachycardia related to the previous surgical scar. The patient had successful non-contact mapping and radiofrequency ablation of the offending tachycardia substrate. 相似文献
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104.
Dhakshinamurthy Vijay Anand Eric Lim Daniel Darko Paul Bassett David Hopkins David Lipkin Roger Corder Avijit Lahiri 《Journal of the American College of Cardiology》2007,50(23):2218-2225
OBJECTIVES: This study prospectively evaluated the relationship between cardiovascular risk factors, selected biomarkers (high-sensitivity C-reactive protein [hs-CRP], interleukin [IL]-6, and osteoprotegerin [OPG]), and the progression of coronary artery calcification (CAC) in type 2 diabetic subjects. BACKGROUND: Coronary artery calcification is pathognomonic of coronary atherosclerosis. Osteoprotegerin is a signaling molecule involved in bone remodeling that has been implicated in the regulation of vascular calcification and atherogenesis. METHODS: Three hundred ninety-eight type 2 diabetic subjects without prior coronary disease or symptoms (age 52 +/- 8 years, 61% male, glycated hemoglobin [HbA(1)c] 8 +/- 1.5) were evaluated serially by CAC imaging (mean follow-up 2.5 +/- 0.4 years). Progression/regression of CAC was defined as a change > or =2.5 between the square root transformed values of baseline and follow-up volumetric CAC scores. Demographic data, risk factors, glycemic control, medication use, serum hs-CRP, IL-6, and plasma OPG levels were measured at baseline and follow-up. RESULTS: Two hundred eleven patients (53%) had CAC at baseline. One hundred eighteen patients (29.6%) had CAC progression, whereas 3 patients (0.8%) had regression. Age, male gender, hypertension, baseline CAC, HbA(1)c >7, waist-hip ratio, IL-6, OPG, use of beta-blockers, calcium channel antagonists, angiotensin-converting enzyme (ACE) inhibitors, statins, and Framingham/UKPDS (United Kingdom Prospective Diabetes Study) risk scores were univariable predictors of CAC progression. In the multivariate model, baseline CAC (odds ratio [OR] for CAC >400 = 6.38, 95% confidence interval [CI] 2.63 to 15.5, p < 0.001), HbA(1)c >7 (OR 1.95, CI 1.08 to 3.52, p = 0.03), and statin use (OR 2.27, CI 1.38 to 3.73, p = 0.001) were independent predictors of CAC progression. CONCLUSIONS: Baseline CAC severity and suboptimal glycemic control are strong risk factors for CAC progression in type 2 diabetic subjects. 相似文献
105.
Sengupta PP Krishnamoorthy VK Abhayaratna WP Korinek J Belohlavek M Sundt TM Chandrasekaran K Seward JB Tajik AJ Khandheria BK 《The American journal of cardiology》2008,102(3):357-362
Brain (B-type) natriuretic peptide (BNP) and tissue Doppler imaging may distinguish restrictive cardiomyopathy (RCMP) from idiopathic constrictive pericardial disease (CP). However, their comparative efficacy is unknown for patients with CP from secondary causes (e.g., surgery or radiotherapy). We compared the efficacy of tissue Doppler imaging and BNP for differentiation of RCMP (n = 15) and CP (n = 16) were compared. BNP was higher in patients with RCMP than CP (p = 0.008), but the groups overlapped, particularly for BNP <400 pg/ml. BNP was lower with idiopathic CP than secondary CP (139 +/- 50 vs 293 +/- 69 pg/ml; p <0.001) or RCMP (139 +/- 50 vs 595 +/- 499 pg/ml; p <0.001), but not significantly different between those with secondary CP and RCMP (293 +/- 69 vs 595 +/- 499 pg/ml; p = 0.1). Patients with CP and RCMP had less overlap in early diastolic and isovolumic contraction tissue Doppler imaging velocities compared with BNP, with clear separation of groups evident with mean early diastolic annular velocities (averaged from 4 walls). Early diastolic tissue Doppler imaging velocity was superior to BNP for differentiation of CP and RCMP (area under the curve 0.97 vs 0.76, respectively; p = 0.01). In conclusion, mean early diastolic mitral annular velocity correctly distinguished CP from RCMP even when there was a large overlap of BNP between the 2 groups. 相似文献
106.
This paper presents model-based information-theoretic methods to quantify the complexity of tumor microvasculature, taking into account shape, textural, and structural irregularities. The proposed techniques are completely automated, and are applicable to optical slices (3-D) or projection images (2-D). Improvements upon the prior literature include: (i) measuring local (vessel segment) as well as global (entire image) vascular complexity without requiring explicit segmentation or tracing; (ii) focusing on the vessel boundaries in the complexity estimate; and (iii) added robustness to image artifacts common to tumor microvasculature images. Vessels are modeled using a family of super-Gaussian functions that are based on the superquadric modeling primitive common in computer vision. The superquadric generalizes a simple ellipsoid by including shape parameters that allow it to approximate a cylinder with elliptical cross-sections (generalized cylinder). The super-Gaussian is obtained by composing a superquadric with an exponential function giving a form that is similar to a standard Gaussian function but with the ability to produce level sets that approximate generalized cylinders. Importantly, the super-Gaussian is continuous and differentiable so it can be fit to image data using robust non-linear regression. This fitting enables quantification of the intrinsic complexity of vessel data vis-a-vis the super-Gaussian model within a minimum message length (MML) framework. The resulting measures are expressed in units of information (bits). Synthetic and real-data examples are provided to illustrate the proposed measures. 相似文献
107.
Dale Maharaj Michael Ramdass Andrew Perry Vijay Naraynsingh 《The International journal of angiology》2003,12(2):143-144
Axillary vein thrombosis, or Paget von Schroetter syndrome, is a rare clinical condition. It is associated with several thrombogenic states and numerous sporting activities involving excessive use of the arm. We report one such case associated with exotic dancing. In societies where dancing involves excessive arm movement, the physician must be aware of this condition to permit early diagnosis and effective treatment. 相似文献
108.
Akhil Kapoor Vanita Noronha Vijay M. Patil Nandini Menon Amit Joshi George Abraham Kumar Prabhash 《Medicine》2021,100(13)
Immune checkpoint inhibitors (ICIs) are rapidly being incorporated as treatment option either alone or in combination with chemotherapy in most of the solid tumors. Since there is very limited data of ICI in patients with poor performance status (PS) from the real world settings, we performed a retrospective audit of patients who received ICI and report the analysis based on ECOG PS of these patients.This study is a retrospective audit of a prospectively collected database of patients receiving ICIs for advanced solid tumors in any line between August 2015 and November 2018 at Tata Memorial Hospital, Mumbai, India. All statistical calculations were performed using SPSS statistical software for windows version 20.0.A total of 155 patients who received ICIs during the specified period were evaluated for this study. Baseline ECOG PS 0–1 (n = 103, 66.4%) patients was associated with median OS 9.1 (95% CI [confidence interval], 4.4-NR) months when compared to ECOG 2–4 (n = 52, 33.5%) which had a median OS of 2.9 (95% CI; 1.8–5.5) months (HR, 1.7, 95% CI, 1.1–2.7, log rank P = .017). The disease control rate for the poor PS group was 34.6%. However, 27.3% patients (95% CI: 20.3–34.3) were still alive at 1 year. Median OS in patients with PS 2 was 3.7 months (95% CI: 0–11.6) as compared to 1.8 months (95% CI: 0.2–3.4) for those with PS 3–4 (HR-2.0; 95% CI: 1.0–3.9, P = .041). The tolerance to ICIs was good with no grade 3/4 toxicities in 44 (84.6%) patients.Immune checkpoint inhibitors are a safe and effective therapeutic option even in solid tumor patients with poor performance status. 相似文献
109.
As one targeting strategy of prodrug delivery, gene-directed enzyme prodrug therapy (GDEPT) promises to realize the targeting through its three key features in cancer therapy—cell-specific gene delivery and expression, controlled conversion of prodrugs to drugs in target cells, and expanded toxicity to the target cells’ neighbors through bystander effects. After over 20 years of development, multiple GDEPT systems have advanced into clinical trials. However, no GDEPT product is currently marketed as a drug, suggesting that there are still barriers to overcome before GDEPT becomes a standard therapy. In this review, we first provide a general introduction of this prodrug targeting strategy. Then, we utilize the four most thoroughly studied systems to illustrate components, mechanisms, preclinical and clinical results, and further development directions of GDEPT. These four systems are herpes simplex virus thymidine kinase/ganciclovir, cytosine deaminase/5-fluorocytosine, cytochrome P450/oxazaphosphorines, and nitroreductase/CB1954 system. Later, we focus our discussion on bystander effects including local and distant bystander effects. Lastly, we discuss carriers that are used to deliver genes for GDEPT including virus carriers and non-virus carriers. Among these carriers, the stem cell-based gene delivery system represents one of the newest carriers under development, and may brought about a breakthrough to the gene delivery issue of GDEPT.KEY WORDS: bystander effects, gene delivery, gene-directed enzyme, prodrug, stem cell-based targeting 相似文献
110.
Jones Brian E. Allegretti Andrew S. Pose Elisa Mara Kristin C. Ufere Nneka N. Avitabile Emma Shah Vijay H. Kamath Patrick S. Gins Pere Simonetto Douglas A. 《Digestive diseases and sciences》2022,67(2):697-707
Digestive Diseases and Sciences - Acute kidney injury is seen in approximately 30% of patients with severe alcohol-associated hepatitis (AH) and is associated with increased mortality. Controversy... 相似文献