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"Taking stock: a meta-analysis of the virtual public sphere in communication journals"
Large eddy simulation of dispersion of hazardous materials released from a fire accident around a cubical building
The turbulent smoke dispersion from a pool fire around a cubical building is studied using large eddy simulation at a high Reynolds number, corresponding to existing experimental measurements both in laboratory and field test scales. Emphasis of this work is on the smoke dispersion due to two different fuel pool fire accident scenarios, initiated behind the building. For the setup of fire in the first case, crude oil was used with a heat release rate of 7.8 MW, and in the second, diesel oil with a heat release rate of 13.5 MW. It is found that in both fire scenarios, the downstream extent of the toxic zone is approximately the same. This is explained in terms of the fact that the smoke concentration and dispersion are influenced mainly by the convective buoyant forces and the strong turbulence mixing processes within the wake zone of the building. It is suggested that wind is the dominating factor in these accident scenarios, which represent the conditions resulting in the highest toxicity levels
Vascular conditioning prevents adverse left ventricular remodelling after acute myocardial infarction: a randomised remote conditioning study
Aims:
Remote ischemic conditioning (RIC) alleviates ischemia–reperfusion injury via several pathways, including micro-RNAs (miRs) expression and oxidative stress modulation. We investigated the effects of RIC on endothelial glycocalyx, arterial stiffness, LV remodelling, and the underlying mediators within the vasculature as a target for protection.
Methods and results:
We block-randomised 270 patients within 48 h of STEMI post-PCI to either one or two cycles of bilateral brachial cuff inflation, and a control group without RIC. We measured: (a) the perfusion boundary region (PBR) of the sublingual arterial microvessels to assess glycocalyx integrity; (b) the carotid-femoral pulse wave velocity (PWV); (c) miR-144,-150,-21,-208, nitrate-nitrite (NOx) and malondialdehyde (MDA) plasma levels at baseline (T0) and 40 min after RIC onset (T3); and (d) LV volumes at baseline and after one year. Compared to baseline, there was a greater PBR and PWV decrease, miR-144 and NOx levels increase (p 15% (odds-ratio of 3.75, p = 0.029). MiR-144 and PWV changes post-RIC were interrelated and associated with LVESV reduction at follow-up (r = 0.40 and 0.37, p < 0.05), in the single-cycle RIC.
Conclusion:
RIC evokes “vascular conditioning” likely by upregulation of cardio-protective microRNAs, NOx production, and oxidative stress reduction, facilitating reverse LV remodelling
Guidelines On Diabetes, Pre-Diabetes, And Cardiovascular Diseases: Executive Summary.The Task Force on Diabetes and Cardiovascular Diseases of the European Society of Cardiology (ESC) and of the European Association for the Study of Diabetes (EASD).
Guidelines and Expert Consensus documents aim to present
management and recommendations based on all of the
relevant evidence on a particular subject in order to help
physicians to select the best possible management strategies
for the individual patient, suffering from a specific condition,
taking into account not only the impact on outcome, but also
the risk benefit ratio of a particular diagnostic or therapeutic
procedure. The ESC recommendations for guidelines
production can be found on the ESC website†.
In brief, the ESC appoints experts in the field to carry out a
comprehensive and critical evaluation of the use of diagnostic
and therapeutic procedures and to assess the risk–benefit ratio
of the therapies recommended for management and/or prevention
of a given condition. The strength of evidence for or
against particular procedures or treatments is weighed according
to predefined scales for grading recommendations and
levels of evidence, as outlined below. Once the document
has been finalized and approved by all the experts involved
in the Task Force, it is submitted to outside specialists for
review. If necessary, the document is revised once more to
be finally approved by the Committee for Practice Guidelines
and selected members of the Board of the ESC.
The ESC Committee for Practice Guidelines (CPG)
supervises and coordinates the preparation of new
Guidelines and Expert Consensus Documents produced by
Task Forces, expert groups, or consensus panels. The chosen
experts in these writing panels are asked to provide disclosure
statements of all relationships they may have, which
might be perceived as real or potential conflicts of interest.
These disclosure forms are kept on file at the European
Heart House, headquarters of the ESC. The Committee is
also responsible for the endorsement of these Guidelines
and Expert Consensus Documents or statements
Assessment of endothelial function by brachial artery flow mediated dilatation in microvascular disease
<p>Abstract</p> <p>Background</p> <p>Cardiac syndrome X is an important therapeutic and diagnostic challenge to physician. Study of Csx patients may help to understand the pathophysiology of coronary microcirculation and to gain an insight on the management of these group patients.</p> <p>Methods</p> <p>We measured the flow mediated dilation of the brachial artery both endothelium dependent and independent vasodilatation by high resolution ultrasound in 30 cardiac syndrome X patients and matched with 30 healthy control subjects.</p> <p>Results</p> <p>Significantly decreased flow mediated dilatation was observed in patients when compared to control (9.42 ± 7.20 vs 21.11 ± 9.16 p < 0.01) but no significant difference was observed between groups in response to nitroglycerin (25.39 ± 6.82 vs 28.87 ± 8.69). Receiver operator characteristic analysis showed that value of < 11.11 had sensitivity of 80%, specificity 86.67%, positive predictive value 76.66%, negative predictive value 83.33%. In total, 46% of subjects had endothelial dysfunction and of them, CSX subjects had higher prevalence (76% vs 16% p < 0.01) than control subjects. Higher mean values of body mass index, systolic blood pressure and diastolic blood pressure was observed in subjects with FMD < 11.11 than > 11.11(p < 0.01). In logistic regression analysis, FMD was significantly associated with systolic blood pressure (Odds ratio 1.122 95% CI 1.053-1.196 p < 0.01) and body mass index (Odds 1.248 95%CI 0.995-1.56 p < 0.05).</p> <p>Conclusions</p> <p>The study suggests impairment of endothelial function in cardiac syndrome X patients. Increased Systolic blood pressure and body mass index may increase the risk of impairment of endothelial function in this group of patients.</p
Guidelines on the management of valvular heart disease: The Task Force on the Management of Valvular Heart Disease of the European Society of Cardiology.
80These guidelines focus on valvular heart disease in adults and adolescents, are
oriented towards management, and will not deal with endocarditis
and congenital valve diseases in adults and
adolescents, since recent guidelines have been produced
by the ESC on these topics. Although valvular heart disease is less common in
industrialized countries than coronary disease, heart
failure, or hypertension, guidelines are needed in this
field for several reasons: valvular heart disease is common and often requires intervention; substantial advances have been made in the understanding
of its pathophysiology; the patient population has changed with a continuous
decline of acute rheumatic fever and an increased
incidence
of degenerative valvular diseases in industrialized
countries. The incidence of endocarditis remains stable and
other causes of valve disease are rare. Because of the predominance
of degenerative valve disease, the two most frequent
valve diseases are now calcific aortic stenosis and
mitral regurgitation. Aortic regurgitation and mitral stenosis have become less common. Diagnosis is now dominated by echocardiography, which
has become the standard to evaluate valve structure and
function. Treatment has not only developed through the continuing
progress in prosthetic valve technology, but has also been
reoriented by the development of conservative surgical
approaches and the introduction of percutaneous interventional
techniques.openopenVahanian, A; Baumgartner, ; H, ; Bax, ; J, ; Butchart, ; E, ; Dion, ; R, ; Filippatos, ; G, ; Flachskampf, ; F, ; Hall, ; R, ; Iung, ; B, ; Kasprzak, ; J, ; Nataf, ; P, ; Tornos, ; P, ; Torracca, ; L, ; Wenink, ; A, ; Silvia, ; Priori, G.; Blanc, Jean-Jacques; Andrzej, ; Budaj, ; John, ; Camm, ; Veronica, ; Dean, ; Jaap, ; Deckers, ; Kenneth, ; Dickstein, ; John, ; Lekakis, ; Keith, ; Mcgregor, ; Marco, ; Metra, ; João, ; Morais, ; Ady, ; Osterspey, ; Juan, ; Tamargo, ; Luis, José; Zamorano, ; Annalisa, ; Angelini, ; Manuel, ; Antunes, ; Angel, Miguel; Fernandez, Garcia; Christa, ; Gohlke-Baerwolf, ; Gilbert, ; Habib, ; John, ; Mcmurray, ; Catherine, ; Otto, ; Luc, ; Pierard, ; Josè, ; Pomar, L.; Bernard, ; Prendergast, ; Raphael, ; Rosenhek, ; Sousa, Miguel; Uva, ; Juan, ; Tamargo,Vahanian, A; Baumgartner, ; H, ; Bax, ; J, ; Butchart, ; E, ; Dion, ; R, ; Filippatos, ; G, ; Flachskampf, ; F, ; Hall, ; R, ; Iung, ; B, ; Kasprzak, ; J, ; Nataf, ; P, ; Tornos, ; P, ; Torracca, ; L, ; Wenink, ; A, ; Silvia, ; Priori, G.; Blanc, Jean Jacques; Andrzej, ; Budaj, ; John, ; Camm, ; Veronica, ; Dean, ; Jaap, ; Deckers, ; Kenneth, ; Dickstein, ; John, ; Lekakis, ; Keith, ; Mcgregor, ; Marco, ; Metra, Marco; João, ; Morais, ; Ady, ; Osterspey, ; Juan, ; Tamargo, ; Luis, José; Zamorano, ; Annalisa, ; Angelini, ; Manuel, ; Antunes, ; Angel, Miguel; Fernandez, Garcia; Christa, ; Gohlke, Baerwolf; Gilbert, ; Habib, ; John, ; Mcmurray, ; Catherine, ; Otto, ; Luc, ; Pierard, ; Josè, ; Pomar, L.; Bernard, ; Prendergast, ; Raphael, ; Rosenhek, ; Sousa, Miguel; Uva, ; Juan, ; Tamargo
The Dopamine D3 Receptor Knockout Mouse Mimics Aging-Related Changes in Autonomic Function and Cardiac Fibrosis
Blood pressure increases with age, and dysfunction of the dopamine D3 receptor has been implicated in the pathogenesis of hypertension. To evaluate the role of the D3 receptor in aging-related hypertension, we assessed cardiac structure and function in differently aged (2 mo, 1 yr, 2 yr) wild type (WT) and young (2 mo) D3 receptor knockout mice (D3KO). In WT, systolic and diastolic blood pressures and rate-pressure product (RPP) significantly increased with age, while heart rate significantly decreased. Blood pressure values, heart rate and RPP of young D3KO were significantly elevated over age-matched WT, but similar to those of the 2 yr old WT. Echocardiography revealed that the functional measurements of ejection fraction and fractional shortening decreased significantly with age in WT and that they were significantly smaller in D3KO compared to young WT. Despite this functional change however, cardiac morphology remained similar between the age-matched WT and D3KO. Additional morphometric analyses confirmed an aging-related increase in left ventricle (LV) and myocyte cross-sectional areas in WT, but found no difference between age-matched young WT and D3KO. In contrast, interstitial fibrosis, which increased with age in WT, was significantly elevated in the D3KO over age-matched WT, and similar to 2 yr old WT. Western analyses of myocardial homogenates revealed significantly increased levels of pro- and mature collagen type I in young D3KO. Column zymography revealed that activities of myocardial MMP-2 and MMP-9 increased with age in WTs, but in D3KO, only MMP-9 activity was significantly increased over age-matched WTs. Our data provide evidence that the dopamine D3 receptor has a critical role in the emergence of aging-related cardiac fibrosis, remodeling, and dysfunction
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