Quantitative gated blood pool tomographic assessment of regional ejection fraction: Definition of normal limits

AbstractObjective. Our aim was to select a method of analysis for gated blood pool tomography that reduced variability in a group of normal subjects, allowed comparison with normal limit files and displayed results in the bull's-eye format.Background. Abnormalities in left ventricular function may not be accurately detected by measures of global function because hyperkuiesia in normal regions may compensate for abnormal regional function. Gated blood pool tomography acquires threedimensional data and offers advantages over other noninvasive modalities Tor quantitative assessment of global and regional function.Methods. Alternative methods for selecting the ventricular axis, calculating regional ejection fraction and choosing the number of ventricular divisions were studied In 15 normal volunteers to select the combination of parameter that produced the lowest variability in quantitative regional ejection fraction. Methods for quantitative comparison, of regional ejection fraction with normal limit files and for display in the bull's-eye format were also examined.Results. A fixed axis (the geometric center of the ventricle defined for end-diastole and used for end-systole) gave ejection fractions that were significantly higher in the lateral wall versus in the septum, 82 ± 8 (mean ± 1 SD) versus 39 ± 17 (p < 0.001) at the midcavity and 66 ± 11 versus 21 ± 20 (p < 0.001) at the base. A floating axis system (axis defined individually for end-diastole and end-systole and realigned at the center) gave more uniform regional ejection fraction: 63 ±6 versus 64 ± 8 (p = NS) at the midcavity and 44 ± 16 versus 45 ± 15 (p = NS) at the base. The coefficient of variability for regional ejection fraction was consistently lower using a floating axis. Calculating regional ejection fraction by dividing the regional stroke volume by the enddiastollc volume of the region gave a lower coefficient of variability and a more easily understood value than dividing the regional stroke volume by the total end-diastolic volume of the ventricle. Although the variability was lower using five versus nine ventricular divisions, nine regions offer greater spatial resolution. Comparison of regional ejection fraction with normal data identified regions > 2.5 SD below the mean as abnormal. We described the two-dimensional bull's-eye format as a method for displaying the regional three-dimensional data and illustrated abnormalities in patients with prior myocardial infarction.Conclusions. Gated blood pool tomography performed using a floating axis system, regional stroke volume calculation of ejection fraction and nine regions uses all the three-dimensional blood pool data to calculate regional ejection fraction, allow quantitative comparison with normal limit tiles, display the functional data in the two-dimensional bull's-eye format and demonstrate abnormalities in patients with myocardial infarction

Perioperative cardiac events in endovascular repair of complex aortic aneurysms and association with preoperative studies

BackgroundEndovascular repair of complex aortic aneurysms (CAAs) can be performed in high-risk individuals, yet is still associated with significant morbidity, including spinal cord ischemia, cardiac complications, and death. This analysis was undertaken to better define the cardiac risk for CAA.MethodsA prospective database of patients undergoing thoracoabdominal or juxtarenal aortic aneurysm repair with branched and fenestrated endografts was used to retrospectively determine the number of cardiac events, defined as myocardial infarction (MI), atrial fibrillation (AF), and ventricular arrhythmia (VA), that occurred ≤30 days of surgery. Postoperative serial troponin measurements were performed in 266 patients. Any additional available cardiac information, including preoperative echocardiography, physiologic stress tests, and history of cardiac disease, was obtained from medical records. The efficacy of preoperative stress testing and the association of various echo parameters were evaluated in the context of cardiac outcomes using univariable and multivariable logistic regression models.ResultsBetween August 2001 and December 2007, 395 patients underwent endovascular repair of a thoracoabdominal or juxtarenal aortic aneurysm. The incidence of AF, VA, and 30-day cardiac-related death was 9%, 3%, and 2%, respectively. Overall 30-day mortality was 6%. Univariable analysis showed the presence of mitral annulus calcification was associated with MI (odds ratio [OR], 3.5; 95% confidence interval [CI], 0.9-13.8; P = .07). Left atrium cavity area, ejection fraction, left ventricle mass, and left ventricular mass index were univariably associated with the presence of VA. Multivariable analysis showed only the left atrium cavity area was independently associated with VA (OR, 1.2; 95% CI, 1.0-1.5; P = .07). Stress test was done in 179 patients. Negative stress test results occurred in 152 (85%), of whom 9 (6%) sustained an MI during the 30-day perioperative course. MI occurred in 2 of the 27 patients (7%) who had a positive stress test result.ConclusionsEndovascular repair of CAA can be performed in high-risk individuals but is associated with significant cardiac risk. It remains difficult to risk stratify patients using preoperative stress testing. Echo evaluation may help to identify patients who may be more likely to develop ventricular arrhythmias in the postoperative period and thus warrant closer monitoring. Postoperative troponin monitoring of all patients undergoing repair of CAA is warranted given the overall risk of MI

Cork extracts reduce UV-mediated DNA fragmentation and cell death

Accepted ManuscriptUV radiation is known to induce the premature aging of human skin and to contribute to the occurrence of different skin cancers. High doses of UVA (able to penetrate through the epidermis into the dermis) and/or UVB radiation (only affecting the epidermis) leads to cellular oxidative damage compromising the recovery of the normal functions of the cells. This cellular damage is mainly driven by the generation of reactive oxygen species (ROS) that alter the redox status of the intracellular milieu, affecting the cellular metabolic activity, leading to DNA damage, apoptosis and, consequently, to a drastic decrease in the number of live cells, compromising the function of the skin. A series of polyphenolic fractions were extracted from the outer bark (cork) of Quercus suber L., and tested for their capacity to reduce the cellular damage promoted by the ROS produced during UV exposure. This was evaluated after exposing L929 fibroblasts to UV radiation in the presence and absence of the cork extracts. In all the cases the extracts at the concentration of 75μg/ml demonstrated the capacity to preserve cell metabolic activity and their typical morphology, as well as, to avoid DNA fragmentation after exposure to UV radiation. We were also able to correlate these findings with the intracellular reduction of ROS species and the presence of higher proportions of castalagin and vescalagin in the extracts. Our data proves that cork is a relevant source of antioxidant compounds able to act in the cellular environment, protecting cells against oxidation, reducing the number of ROS species and limiting the negative impact of UV radiation. These extracts can be further exploited in the preparation of anti-UV formulations for skin protection.The authors are grateful to Amorim Cork Composites for providing the cork powder raw material and for the financing by the COMPETE/QREN/EU funding program through the project with acronym BioActiveCork (QREN FCOMP-01-0202-FEDER-005455). Ivo M. Aroso and Mariana T. Cerqueira acknowledge the financial support of FCT through the grants SFRH/BD/42273/2007 and SFRH/BPD/96611/2013, respectively. Funding was also granted from the European Union's Seventh Framework Programme (FP7/2007-2013) under grant agreement no. REGPOT-CT2012-316331-POLARIS and from project "Novel smart and biomimetic materials for innovative regenerative medicine approaches (Ref.: RL1-ABMR-NORTE-01-0124-FEDER-000016)" co-financed by North Portugal Regional Operational Programme (ON.2 and "O Novo Norte"), under the National Strategic Reference Framework (NSRF), through the European Regional Development Fund (ERDF) as appropriate

Resveratrol-loaded octenyl succinic anhydride modified starch emulsions and hydroxypropyl methylcellulose (HPMC) microparticles: Cytotoxicity and antioxidant bioactivity assessment after in vitro digestion

Hydroxypropyl methylcellulose (HPMC)-based microparticles and modified starch emulsions (OSA-MS) were loaded with resveratrol and characterized regarding their physicochemical and thermal properties. Both delivery systems were subject to an in vitro gastrointestinal digestion to assess the bioaccessibility of resveratrol. In addition, cell-based studies were conducted after in vitro digestion and cytotoxicity and oxidative stress were assessed. HPMC-based microparticles displayed higher average sizes (d) and lower polydispersity index (PDI) (d = 948 nm, PDI < 0.2) when compared to OSA-MS-based emulsions (d = 217 nm, PDI < 0.3). Both proved to protect resveratrol under digestive conditions, leading to an increase in bioaccessibility. Resveratrol-loaded HPMC-microparticles showed a higher bioaccessibility (56.7 %) than resveratrol-loaded emulsions (19.7 %). Digested samples were tested in differentiated co-cultures of Caco-2 and HT29-MTX, aiming at assessing cytotoxicity and oxidative stress, and a lack of cytotoxicity was observed for all samples. Results displayed an increasing antioxidant activity, with 1.6-fold and 1.4-fold increases over the antioxidant activity of free resveratrol, for HPMC-microparticles and OSA-MS nanoemulsions, respectively. Our results offer insight into physiological relevancy due to assessment post-digestion and highlight the protection that the use of micro-nano delivery systems can confer to resveratrol and their potential to be used as functional food ingredients capable of providing antioxidant benefits upon consumption.This study was supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UIDB/04469/2020 unit, and by LABBELS – Associate Laboratory in Biotechnology, Bioengineering and Microelectromechanical Systems, LA/P/0029/2020 and LAQV/REQUIMTE (UIDB/50006/2020, UIDP/50006/2020). This work was funded by the SbDtoolBox - Nanotechnology-based tools and tests for Safer-by-Design nanomaterials, with the reference NORTE-01-0145-FEDER-000047, funded by Norte 2020 – North-Regional Operational Program under the PORTUGAL 2020 Partnership Agreement, through the European Regional Development Fund (ERDF). The research also received funding from the European Union's H2020 research and innovation program under the Marie Sklodowska-Curie grant agreement N 778388 (H2020 MSCA-RISE-2017 project Food for Diabetes and Cognition (FODIAC), and grant agreement N 713640 (MSCA-2015-COFUND-FP). Pedro Silva is the recipient of a fellowship (SFRD/BD/130247/2017) supported by Fundação para a Ciência e a Tecnologia, (FCT, Portugal). Ana Isabel Bourbon acknowledges funding by FCT, through the individual scientific employment program contract (2020.03447.CEECIND). We also would like to thank the Advanced Electron Microscopy, Imaging, and Spectroscopy (AEMIS) and the Nanophotonics and Bioimaging Facility (NBI) from INL for their support

AHA/ACC Guidelines for Preventing Heart Attack and Death in Patients With Atherosclerotic Cardiovascular Disease: 2001 Update: A Statement for Healthcare Professionals From the American Heart Association and the American College of Cardiology

"Since the original publication (in 1995) of the American Heart Association (AHA) consensus statement on secondary prevention, which was endorsed by the American College of Cardiology (ACC), important evidence from clinical trials has emerged that further supports the merits of aggressive risk reduction therapies for patients with atherosclerotic cardiovascular disease. As noted in that statement, aggressive risk factor management clearly improves patient survival, reduces recurrent events and the need for interventional procedures, and improves the quality of life for these patients. The compelling evidence from recent clinical trials was the impetus to revise the 1995 guidelines (Table). As examples, the many lipid reduction trials have generated significant changes in the National Heart, Lung, and Blood Institute’s Adult Treatment Panel III report. This report further defined target cholesterol levels, expanded indications for drug treatment, and initiated therapy earlier. Accumulating β-blocker data have resulted in broader indications for a larger patient group. The Heart Outcomes Prevention Evaluation (HOPE) trial has demonstrated the benefit of ACE inhibitor therapy in high-risk patients with cardiovascular disease without a history of an acute event. Further data from ongoing trials should provide insight into the potential benefits of treating lower risk patients with combined therapies. The Clopidogrel versus Aspirin in Patients at Risk of Ischemic Events (CAPRIE) trial has provided evidence for clopidogrel benefit in certain patients. Diabetes management recommendations have been updated to include recent guidelines from the American Diabetes Association for risk factor management of diabetics and the growing body of evidence showing diabetics at high risk for cardiovascular events. The Heart and Estrogen/progestin Replacement Study (HERS) documented that hormone replacement therapy is ineffective for secondary prevention. The writing group revising this document also considered other important trials and reports, and they are included in the selected reading list.

Depression in medical students: insights from a longitudinal study

Background: Factors associated with depression of medical students are poorly understood. The purpose of this study is to determine the prevalence of depression in medical students, its change during the course, if depression persists for affected students, what are the factors associated with depression and how these factors change over time. Methods: A prospective, longitudinal observational study was conducted at the Medical School of the University of Minho, Portugal, between academic years 2009-2010 to 2012-2013. We included students who maintained their participation by annually completing a questionnaire including Beck Depression Inventory (BDI). Anxiety and burnout were assessed using the State Trait Anxiety Inventory and Maslach Burnout Inventory. Surveys on socio-demographic variables were applied to evaluate potential predictors, personal and academic characteristics and perceived difficulties. ANOVA with multiple comparisons were used to compare means of BDI score. The medical students were organized into subgroups by K-means cluster analyses. ANOVA mixed-design repeated measurement was performed to assess a possible interaction between variables associated with depression. Results: The response rate was 84, 92, 88 and 81% for academic years 2009-2010, 2010-2011,2011-2012 and 2012/2013, respectively. Two hundred thirty-eight medical students were evaluated longitudinally. For depression the prevalence ranged from 21.5 to 12.7% (academic years 2009/2010 and 2012/2013). BDI scores decreased during medical school. 19.7% of students recorded sustained high BDI over time. These students had high levels of trait-anxiety and choose medicine for anticipated income and prestige, reported more relationship issues, cynicism, and decreased satisfaction with social activities. Students with high BDI scores at initial evaluation with low levels of trait-anxiety and a primary interest in medicine as a career tended to improve their mood and reported reduced burnout, low perceived learning problems and increased satisfaction with social activities at last evaluation. No difference was detected between men and women in the median BDI score over time. Conclusions: Our findings suggest that personal factors (anxiety traits, medicine choice factors, relationship patterns and academic burnout) are relevant for persistence of high levels of BDI during medical training. Medical schools need to identity students who experience depression and support then, as early as possible, particularly when depression has been present over time.info:eu-repo/semantics/publishedVersio

Measurement of the W-boson mass in pp collisions at √s=7 TeV with the ATLAS detector

A measurement of the mass of the W boson is presented based on proton–proton collision data recorded in 2011 at a centre-of-mass energy of 7 TeV with the ATLAS detector at the LHC, and corresponding to 4.6 fb−1 of integrated luminosity. The selected data sample consists of 7.8×106 candidates in the W→μν channel and 5.9×106 candidates in the W→eν channel. The W-boson mass is obtained from template fits to the reconstructed distributions of the charged lepton transverse momentum and of the W boson transverse mass in the electron and muon decay channels, yielding mW=80370±7 (stat.)±11(exp. syst.) ±14(mod. syst.) MeV =80370±19MeV, where the first uncertainty is statistical, the second corresponds to the experimental systematic uncertainty, and the third to the physics-modelling systematic uncertainty. A measurement of the mass difference between the W+ and W−bosons yields mW+−mW−=−29±28 MeV