1,683 research outputs found

    Slope of the anterior mitral valve leaflet: A new measurement of left ventricular unloading for left ventricular assist devices and systolic dysfunction

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    Left ventricular assist device (LVAD)-supported patients are evaluated routinely with use of transthoracic echocardiography. Values of left ventricular unloading in this unique patient population are needed to evaluate LVAD function and assist in patient follow-up. We introduce a new M-mode measurement, the slope of the anterior mitral valve leaflet (SLAM), and compare its efficacy with that of other standard echocardiographically evaluated values for left ventricular loading, including E/e′ and pulmonary artery systolic pressures. Average SLAM values were determined retrospectively for cohorts of random, non-LVAD patients with moderately to severely impaired left ventricular ejection fraction (LVEF) (<0.35, n=60). In addition, pre- and post-LVAD implantation echocardiographic images of 81 patients were reviewed. The average SLAM in patients with an LVEF <0.35 was 11.6 cm/s (95% confidence interval, 10.4–12.8); SLAM had a moderately strong correlation with E/e′ in these patients. Implantation of LVADs significantly increased the SLAM from 7.3 ± 2.44 to 14.7 ± 5.01 cm/s (n=42, P <0.0001). The LVAD-supported patients readmitted for exacerbation of congestive heart failure exhibited decreased SLAM from 12 ± 3.93 to 7.3 ± 3.5 cm/s (n=6, P=0.041). In addition, a cutpoint of 10 cm/s distinguished random patients with LVEF <0.35 from those in end-stage congestive heart failure (pre-LVAD) with an 88% sensitivity and a 55% specificity. Evaluating ventricular unloading in LVAD patients remains challenging. Our novel M-mode value correlates with echocardiographic values of left ventricular filling in patients with moderate-to-severe systolic function and dynamically improves with the ventricular unloading of an LVAD

    Cardiovascular disease in late survivors of tetralogy of Fallot: A tertiary care center experience

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    Patients with tetralogy of Fallot can survive to late adulthood; however, there are few data on cardiovascular outcomes in this population. We conducted a single-center retrospective analysis of cardiovascular outcomes and risk factors in 208 patients with tetralogy of Fallot to better evaluate the burden of cardiovascular disease in this group. Descriptive statistics were used to determine the prevalence of relevant cardiovascular risk factors and outcomes, including a composite analysis of cardiovascular disease. Rates and mean values from the American Heart Association 2011 Heart Disease and Stroke Statistics Update were used as population estimates for comparison. In tetralogy of Fallot patients, cardiovascular disease prevalence was not different from that found in the general population (40% vs 36%, P=0.3). However, there was significantly more cardiovascular disease in tetralogy of Fallot men aged 20 to 39 years (30% vs 14%, P < 0.05) and in tetralogy of Fallot men aged 40 to 59 years (63% vs 29%, P < 0.0001). This was due to higher prevalence of coronary disease (12% vs 7%, P < 0.05) and heart failure (16% vs 2%, P < 0.0001). In particular, the increased prevalence of heart failure (regardless of pulmonary valve disease) accounts for the frequency of cardiovascular disease in tetralogy of Fallot men aged 20 to 59 years. These data support the need to routinely screen young adult male survivors of tetralogy of Fallot for asymptomatic heart failure. Further studies are needed to determine the incidence, severity, and long-term effects of cardiovascular disease in the adult congenital heart disease population

    Instructional Message Design: Theory, Research, and Practice (Volume 2)

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    Message design is all around us, from the presentations we see in meetings and classes, to the instructions that come with our latest tech gadgets, to multi-million-dollar training simulations. In short, instructional message design is the real-world application of instructional and learning theories to design the tools and technologies used to communicate and effectively convey information. This field of study pulls from many applied sciences including cognitive psychology, industrial design, graphic design, instructional design, information technology, and human performance technology to name just a few. In this book we visit several foundational theories that guide our research, look at different real-world applications, and begin to discuss directions for future best practice. For instance, cognitive load and multimedia learning theories provide best practice, virtual reality and simulations are only a few of the multitude of applications. Special needs learners and designing for online, e-learning, and web conferencing are only some of many applied areas where effective message design can improve outcomes. Studying effective instructional message design tools and techniques has and will continue to be a critical aspect of the overall instructional design process. Hopefully, this book will serve as an introduction to these topics and inspire your curiosity to explore further!https://digitalcommons.odu.edu/distancelearning_books/1003/thumbnail.jp

    Gastric bypass and banding equally improve insulin sensitivity and β cell function

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    Bariatric surgery in obese patients is a highly effective method of preventing or resolving type 2 diabetes mellitus (T2DM); however, the remission rate is not the same among different surgical procedures. We compared the effects of 20% weight loss induced by laparoscopic adjustable gastric banding (LAGB) or Roux-en-Y gastric bypass (RYGB) surgery on the metabolic response to a mixed meal, insulin sensitivity, and \u3b2 cell function in nondiabetic obese adults. The metabolic response to meal ingestion was markedly different after RYGB than after LAGB surgery, manifested by rapid delivery of ingested glucose into the systemic circulation, by an increase in the dynamic insulin secretion rate, and by large, early postprandial increases in plasma glucose, insulin, and glucagon-like peptide-1 concentrations in the RYGB group. However, the improvement in oral glucose tolerance, insulin sensitivity, and overall \u3b2 cell function after weight loss were not different between surgical groups. Additionally, both surgical procedures resulted in a similar decrease in adipose tissue markers of inflammation. We conclude that marked weight loss itself is primarily responsible for the therapeutic effects of RYGB and LAGB on insulin sensitivity, \u3b2 cell function, and oral glucose tolerance in nondiabetic obese adults

    The Amyotrophic Lateral Sclerosis M114T PFN1 Mutation Deregulates Alternative Autophagy Pathways and Mitochondrial Homeostasis

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    International audienceMutations in profilin 1 (PFN1) have been identified in rare familial cases of Amyotrophic Lateral Sclerosis (ALS). PFN1 is involved in multiple pathways that could intervene in ALS pathology. However, the specific pathogenic role of PFN1 mutations in ALS is still not fully understood. We hypothesized that PFN1 could play a role in regulating autophagy pathways and that PFN1 mutations could disrupt this function. We used patient cells (lymphoblasts) or tissue (post-mortem) carrying PFN1 mutations (M114T and E117G), and designed experimental models expressing wild-type or mutant PFN1 (cell lines and novel PFN1 mice established by lentiviral transgenesis) to study the effects of PFN1 mutations on autophagic pathway markers. We observed no accumulation of PFN1 in the spinal cord of one E117G mutation carrier. Moreover, in patient lymphoblasts and transfected cell lines, the M114T mutant PFN1 protein was unstable and deregulated the RAB9-mediated alternative autophagy pathway involved in the clearance of damaged mitochondria. In vivo, motor neurons expressing M114T mutant PFN1 showed mitochondrial abnormalities. Our results demonstrate that the M114T PFN1 mutation is more deleterious than the E117G variant in patient cells and experimental models and suggest a role for the RAB9-dependent autophagic pathway in ALS

    Instructional Message Design: Theory, Research, and Practice (Volume 2)

    Get PDF
    Message design is all around us, from the presentations we see in meetings and classes, to the instructions that come with our latest tech gadgets, to multi-million-dollar training simulations. In short, instructional message design is the real-world application of instructional and learning theories to design the tools and technologies used to communicate and effectively convey information. This field of study pulls from many applied sciences including cognitive psychology, industrial design, graphic design, instructional design, information technology, and human performance technology to name just a few. In this book we will visit several foundational theories that guide our research, look at different real-world applications, and begin to discuss directions for future best practice. For instance, cognitive load and multimedia learning theories provide best practice, virtual reality and simulations are only a few of the multitude of applications. Special needs learners and designing for online, e-learning, and web conferencing are only some of many applied areas where effective message design can improve outcomes. Studying effective instructional message design tools and techniques has and will continue to be a critical aspect of the overall instructional design process. Hopefully, this book will serve as an introduction to these topics and inspire your curiosity to explore further
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