246 research outputs found
Investigation of the Cardiovascular Endurance of Dance Majors
Background: College dancers have demonstrated low levels of cardiovascular endurance compared to other athletes, which could be one of the factors that leads to more fatigue and injuries during performance. The effects of an education session on cardiovascular endurance and on college dancers’ attitudes towards cardiovascular exercise outside of dance class have not been previously studied. Purpose: The purpose of this study was to use the accelerated three-minute step test to compare lower level and upper level college dancers’ cardiovascular endurance before and 2 months after an education session emphasizing fitness and exercise. Additionally, assessed were the dancers’ attitudes towards cardiovascular activities outside of dance class and the amount of physical activity that they performed. Subjects: There were 25 subjects, 2 male and 23 female dancers between the ages of 18-30 who were declared as a Bachelor of Fine Arts (BFA) Dance Major or had the intent to declare a BFA Dance Major. Methods: The subjects were divided into the lower level group and the upper level group based on the dance level into which the university dance program placed them. The subjects participated in the accelerated three-minute step test and were grouped into a cardiovascular fitness category based on their heart rate recovery (HRrecovery) ranging from 0 (excellent) to 6 (very poor). The results of the three-minute accelerated step test were presented during an education session along with guidelines to improve cardiovascular endurance. The subjects were retested using the accelerated three-minute step test two months after the education session. The Theory of Planned Behavior (TPB) questionnaire and the International Physical Activity Questionnaire (IPAQ) were administered both before and after the education session. The pre- and post-education results were compared using a 2-way repeated measures ANOVA and post-hoc tests were performed. Results: From the originally recruited 38 subjects, 1 was unable to complete the initial step test and 12 others were unable to complete the second half of the study. A total of 25 dance majors were able to complete the entire study (7 lower level, 18 upper level). Of the initial 37 subjects who completed the step test, only 37.8% were in the recommended fitness categories for dancers of 0-2 (excellent to above average) and 62.2% were in fitness categories 3-6 (average to very poor). Two-factor repeated measures ANOVAs revealed a trend towards a significant interaction between dance level and HRrecovery (F(1)=3.338, P=0.081), and a main effect of time on HRrecovery with HRrecovery before the education session being 117.92± 19.28 bpm and HRrecovery after the education session being 109.64 ± 20.57 bpm (F(1)=4.540, P=0.044). Post hoc t-tests reported that the mean HRrecovery before the education session was similar between the lower level and upper level dancers, but that it was significantly lower for the upper level after the education session (P=0.040). There was no significant interaction of time on the IPAQ (F(1)=0.003, P=0.960), and there was no significant main effect of time (F(1)=0.224, P=0.641), or dance level (F(1)=0.069, P=0.795) on the IPAQ scores. For the TPB Questionnaire, there was a significant main effect of dance level on past behavior with the upper level dancers scoring higher than the lower level dancers (F(1)=5.750, P=0.025). There was no significant interaction of dance level on BMI (F(1)=0.385, P=0.541), but there was a significant main effect of time on BMI (F(1)=0.385, P=0.028). Discussion: At initial testing, almost two-thirds of the subjects had fitness levels that were below the recommendation, indicating that many university dancers have lower cardiovascular endurance and may benefit from increasing it. The subjects showed a statistically significant improvement in their cardiovascular endurance as indicated by their HRrecovery two months after an education session. Specifically, the upper level dancers showed more improvement in their cardiovascular endurance than the lower level dancers. A single education session may be an efficient way to increase college dancers’ cardiovascular endurance, but more research is needed to further evaluate the effects of an education session. Finally, this study continues to support the need for college dance majors to be educated regarding cardiovascular endurance
Identification of Hibernating Myocardium: Comparative Accuracy of Myocardial Contrast Echocardiography, Rest-Redistribution Thallium-201 Tomography and Dobutamine Echocardiography
AbstractObjectives. We sought to evaluate the comparative accuracy of myocardial contrast echocardiography (MCE), quantitative rest-redistribution thallium-201 (Tl-201) tomography and low and high dose (up to 40 μg/kg body weight per min) dobutamine echocardiography (DE) in identifying myocardial hibernation.Background. Myocardial contrast echocardiography can assess myocardial perfusion and may therefore be useful in predicting myocardial hibernation. However, its accuracy in comparison to myocardial perfusion scintigraphy and to that of high dose DE remains to be investigated.Methods. Eighteen patients (aged [±SD] 57 ± 10 years) with stable coronary artery disease and ventricular dysfunction underwent the above three modalities before coronary revascularization. Myocardial contrast echocardiography was achieved with intracoronary Albunex. Rest echocardiographic and Tl-201 studies were repeated ≥6 weeks after revascularization.Results. Of 109 revascularized segments with severe dysfunction, 46 (42%) improved. Left ventricular ejection fraction increased from 38 ± 14% to 45 ± 13% at follow-up (p = 0.003). Rest Tl-201 uptake and the ratio of peak contrast intensity of dysfunctional to normal segments with MCE were higher (p < 0.01) in segments that recovered function compared with those that did not. Myocardial contrast echocardiography, thallium scintigraphy and any contractile reserve during DE had a similar sensitivity (89% to 91%) with a lower specificity (43% to 66%) for recovery of function. A biphasic response during DE was the most specific (83%) and the least sensitive (68%) (p < 0.01). The best concordance with MCE was Tl-201 (80%, kappa 0.57). Changes in ejection fraction after revascularization related significantly to the number of viable dysfunctional segments by all modalities (r = 0.54 to 0.65).Conclusions. In myocardial hibernation, methods evaluating rest perfusion (MCE, Tl-201) or any contractile reserve have a similar high sensitivity but a low specificity for predicting recovery of function. A limited contractile reserve (biphasic response) increases the specificity of DE. Importantly, the three techniques identified all patients who had significant improvement in global ventricular function.(J Am Coll Cardiol 1997;29:985–93)© 1997 by the American College of Cardiolog
Eosinophilic myocarditis mimicking acute coronary syndrome secondary to idiopathic hypereosinophilic syndrome: a case report
<p>Abstract</p> <p>Introduction</p> <p>Eosinophilic myocarditis is a rare form of myocarditis. It is characterized pathologically by diffuse or focal myocardial inflammation with eosinophilic infiltration, often in association with peripheral blood eosinophilia. We report a case of eosinophilic myocarditis secondary to hypereosinophilic syndrome.</p> <p>Case presentation</p> <p>A 74-year-old Caucasian woman with a history of asthma, paroxysmal atrial fibrillation, stroke and coronary artery disease presented to the emergency department of our hospital with chest pain. Evaluations revealed that she had peripheral blood eosinophilia and elevated cardiac enzymes. Electrocardiographic findings were nonspecific. Her electrocardiographic finding and elevated cardiac enzymes pointed to a non-ST-elevated myocardial infarction. Echocardiogram showed a severe decrease in the left ventricular systolic function. Coronary angiogram showed nonobstructive coronary artery disease. She then underwent cardiac magnetic resonance imaging, which showed neither infiltrative myocardial diseases nor any evidence of infarction. This was followed by an endomyocardial biopsy which was consistent with eosinophilic myocarditis. Hematologic workup regarding her eosinophilia was consistent with hypereosinophilic syndrome. After being started on steroid therapy, her peripheral eosinophilia resolved and her symptoms improved. Her left ventricular ejection fraction, however, did not improve.</p> <p>Conclusion</p> <p>Eosinophilic myocarditis can present like an acute myocardial infarction and should be considered in the differential diagnosis of acute coronary syndrome in patients with a history of allergy, asthma or acute reduction of the left ventricular function with or without peripheral eosinophilia.</p
The Aid paradigm for poverty reduction: Does it make sense?
YesWhilst thinking on economic policy for development has undergone many shifts with the perceived weak results of earlier adjustment reforms a new donor consensus has emerged based around the central themes of economic growth, good governance and social development. This paper examines the logic behind this new Aid paradigm and discusses the empirical evidence to support it. A nuanced story is revealed with country circumstances playing a critical role and particular interventions varying in impact across countries. For example, growth does not always lead to gains for the poor that match the national average; public expenditure needs to be targeted to achieve social development but effective targeting is difficult; governance reform may be critical but there is no simple governance blueprint and the corruption-growth association need not always be negative
Prasugrel versus Clopidogrel for Acute Coronary Syndromes without Revascularization
peer reviewedBACKGROUND: The effect of intensified platelet inhibition for patients with unstable angina or myocardial infarction without ST-segment elevation who do not undergo revascularization has not been delineated. METHODS: In this double-blind, randomized trial, in a primary analysis involving 7243 patients under the age of 75 years receiving aspirin, we evaluated up to 30 months of treatment with prasugrel (10 mg daily) versus clopidogrel (75 mg daily). In a secondary analysis involving 2083 patients 75 years of age or older, we evaluated 5 mg of prasugrel versus 75 mg of clopidogrel. RESULTS: At a median follow-up of 17 months, the primary end point of death from cardiovascular causes, myocardial infarction, or stroke among patients under the age of 75 years occurred in 13.9% of the prasugrel group and 16.0% of the clopidogrel group (hazard ratio in the prasugre
Identifying patients with multidrug-resistant tuberculosis who may benefit from shorter durations of treatment.
ObjectiveStudying treatment duration for rifampicin-resistant and multidrug-resistant tuberculosis (MDR/RR-TB) using observational data is methodologically challenging. We aim to present a hypothesis generating approach to identify factors associated with shorter duration of treatment.Study design and settingWe conducted an individual patient data meta-analysis among MDR/RR-TB patients restricted to only those with successful treatment outcomes. Using multivariable linear regression, we estimated associations and their 95% confidence intervals (CI) between the outcome of individual deviation in treatment duration (in months) from the mean duration of their treatment site and patient characteristics, drug resistance, and treatments used.ResultsOverall, 6702 patients with successful treatment outcomes from 84 treatment sites were included. We found that factors commonly associated with poor treatment outcomes were also associated with longer treatment durations, relative to the site mean duration. Use of bedaquiline was associated with a 0.51 (95% CI: 0.15, 0.87) month decrease in duration of treatment, which was consistent across subgroups, while MDR/RR-TB with fluoroquinolone resistance was associated with 0.78 (95% CI: 0.36, 1.21) months increase.ConclusionWe describe a method to assess associations between clinical factors and treatment duration in observational studies of MDR/RR-TB patients, that may help identify patients who can benefit from shorter treatment
Profiling the HER3/PI3K Pathway in Breast Tumors Using Proximity-Directed Assays Identifies Correlations between Protein Complexes and Phosphoproteins
The identification of patients for targeted antineoplastic therapies requires accurate measurement of therapeutic targets and associated signaling complexes. HER3 signaling through heterodimerization is an important growth-promoting mechanism in several tumor types and may be a principal resistance mechanism by which EGFR and HER2 expressing tumors elude targeted therapies. Current methods that can study these interactions are inadequate for formalin-fixed, paraffin-embedded (FFPE) tumor samples.Herein, we describe a panel of proximity-directed assays capable of measuring protein-interactions and phosphorylation in FFPE samples in the HER3/PI3K/Akt pathway and examine the capability of these assays to inform on the functional state of the pathway. We used FFPE breast cancer cell line and tumor models for this study. In breast cancer cell lines we observe both ligand-dependent and independent activation of the pathway and strong correlations between measured activation of key analytes. When selected cell lines are treated with HER2 inhibitors, we not only observe the expected molecular effects based on mechanism of action knowledge, but also novel effects of HER2 inhibition on key targets in the HER receptor pathway. Significantly, in a xenograft model of delayed tumor fixation, HER3 phosphorylation is unstable, while alternate measures of pathway activation, such as formation of the HER3PI3K complex is preserved. Measurements in breast tumor samples showed correlations between HER3 phosphorylation and receptor interactions, obviating the need to use phosphorylation as a surrogate for HER3 activation.This assay system is capable of quantitatively measuring therapeutically relevant responses and enables molecular profiling of receptor networks in both preclinical and tumor models
First divertor physics studies in Wendelstein 7-X
The Wendelstein 7-X (W7-X) optimized stellarator fusion experiment, which went into operation in 2015, has been operating since 2017 with an un-cooled modular graphite divertor. This allowed first divertor physics studies to be performed at pulse energies up to 80 MJ, as opposed to 4 MJ in the first operation phase, where five inboard limiters were installed instead of a divertor. This, and a number of other upgrades to the device capabilities, allowed extension into regimes of higher plasma density, heating power, and performance overall, e.g. setting a new stellarator world record triple product. The paper focuses on the first physics studies of how the island divertor works. The plasma heat loads arrive to a very high degree on the divertor plates, with only minor heat loads seen on other components, in particular baffle structures built in to aid neutral compression. The strike line shapes and locations change significantly from one magnetic configuration to another, in very much the same way that codes had predicted they would. Strike-line widths are as large as 10 cm, and the wetted areas also large, up to about 1.5 m(2), which bodes well for future operation phases. Peak local heat loads onto the divertor were in general benign and project below the 10 MW m(-2) limit of the future water-cooled divertor when operated with 10 MW of heating power, with the exception of low-density attached operation in the high-iota configuration. The most notable result was the complete (in all 10 divertor units) heat-flux detachment obtained at high-density operation in hydrogen
HER2-enriched subtype and novel molecular subgroups drive aromatase inhibitor resistance and an increased risk of relapse in early ER+/HER2+ breast cancer
BACKGROUND: Oestrogen receptor positive/ human epidermal growth factor receptor positive (ER+/HER2+) breast cancers (BCs) are less responsive to endocrine therapy than ER+/HER2- tumours. Mechanisms underpinning the differential behaviour of ER+HER2+ tumours are poorly characterised. Our aim was to identify biomarkers of response to 2 weeks’ presurgical AI treatment in ER+/HER2+ BCs. METHODS: All available ER+/HER2+ BC baseline tumours (n=342) in the POETIC trial were gene expression profiled using BC360™ (NanoString) covering intrinsic subtypes and 46 key biological signatures. Early response to AI was assessed by changes in Ki67 expression and residual Ki67 at 2 weeks (Ki672wk). Time-To-Recurrence (TTR) was estimated using Kaplan-Meier methods and Cox models adjusted for standard clinicopathological variables. New molecular subgroups (MS) were identified using consensus clustering. FINDINGS: HER2-enriched (HER2-E) subtype BCs (44.7% of the total) showed poorer Ki67 response and higher Ki672wk (p<0.0001) than non-HER2-E BCs. High expression of ERBB2 expression, homologous recombination deficiency (HRD) and TP53 mutational score were associated with poor response and immune-related signatures with High Ki672wk. Five new MS that were associated with differential response to AI were identified. HER2-E had significantly poorer TTR compared to Luminal BCs (HR 2.55, 95% CI 1.14–5.69; p=0.0222). The new MS were independent predictors of TTR, adding significant value beyond intrinsic subtypes. INTERPRETATION: Our results show HER2-E as a standardised biomarker associated with poor response to AI and worse outcome in ER+/HER2+. HRD, TP53 mutational score and immune-tumour tolerance are predictive biomarkers for poor response to AI. Lastly, novel MS identify additional non-HER2-E tumours not responding to AI with an increased risk of relapse
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