Publications

Aortic annulus dimensions and leaflet calcification from contrast MSCT predict the need for balloon post-dilatation after TAVI with the Medtronic CoreValve prosthesis

We compared the measurement of aortic leaflet calcification on contrast and non-contrast MSCT and investigated predictors of the need for balloon post-dilatation after TAVI.In 110 patients, who had TAVI with a Medtronic CoreValve prosthesis (MCS) for symptomatic aortic stenosis, calcification of the aortic root was measured on non-contrast MSCT (conventionally) and on contrast MSCT (signal attenuation >450 Houndsfield units). Calcium volume was underestimated on contrast- when compared to non-contrast MSCT: median (IQ-range)=759 (466 to 1295) vs. 2016 (1376 to 3262) and the difference between the two methods increased with higher calcium volumes (correlation coefficient r=0.90). Calcium mass was only slightly underestimated on contrast vs. non-contrast MSCT: median (IQ-range)=441 (268 to 809) vs. 555 (341 to 950) and there was no association between the differences and increasing calcium mass (r=0.17). Balloon post-dilatation was performed for significant aortic regurgitation after TAVI in 11 of 110 patients. When compared to controls, the patients who required balloon post-dilatation had higher aortic leaflet calcium on contrast CT (p<0.01), higher aortic annulus diameters (p<0.01) and higher annulus to prosthesis area ratio (p=0.01). ROC curves demonstrated that aortic root or aortic leaflet calcium measured on either contrast- or non-contrast MSCT showed excellent discrimination for the requirement of balloon post-dilatation (area under ROC >0.80 for all), whereas the discriminatory value of aortic annulus dimensions was moderate (area under ROC=0.69) and that of prosthesis to annulus ratio was poor (area under ROC=0.36).Dense aortic leaflet calcification measured on contrast MSCT discerned well the need for balloon post-dilatation after TAVI with an MCS for significant PAR. Non-contrast MSCT may no longer be needed to quantify aortic root calcium before TAVI.

Serial 2-Dimensional and 3-Dimensional Optical Coherence Tomography Assessment of Overhanging Struts of Drug-Eluting Absorbable Metal Scaffold

No abstract is provided for this article.

How to assess regression of the atherosclerotic plaque

Conference Article| August 01 1993 How to assess regression of the atherosclerotic plaque J. de Feyter Pirn; J. de Feyter Pirn * 1Catheterization Laboratory, Thoraxcenter Bd 432, University Hospital Dijkzigt, Erasmus University Rotterdam, P.O. Box 1738, 3000 DR Rotterdam, The Netherlands *To Whom correspondence should be addressed Search for other works by this author on: This Site PubMed Google Scholar C. Di Mario; C. Di Mario 1Catheterization Laboratory, Thoraxcenter Bd 432, University Hospital Dijkzigt, Erasmus University Rotterdam, P.O. Box 1738, 3000 DR Rotterdam, The Netherlands Search for other works by this author on: This Site PubMed Google Scholar P. W. Serruys; P. W. Serruys 1Catheterization Laboratory, Thoraxcenter Bd 432, University Hospital Dijkzigt, Erasmus University Rotterdam, P.O. Box 1738, 3000 DR Rotterdam, The Netherlands Search for other works by this author on: This Site PubMed Google Scholar J. R. T. C. Roelandt J. R. T. C. Roelandt 1Catheterization Laboratory, Thoraxcenter Bd 432, University Hospital Dijkzigt, Erasmus University Rotterdam, P.O. Box 1738, 3000 DR Rotterdam, The Netherlands Search for other works by this author on: This Site PubMed Google Scholar Biochem Soc Trans (1993) 21 (3): 642–647. https://doi.org/10.1042/bst0210642 Article history Received: March 30 1993 Views Icon Views Article contents Figures & tables Video Audio Supplementary Data Peer Review Share Icon Share Twitter LinkedIn Cite Icon Cite Get Permissions Citation J. de Feyter Pirn, C. Di Mario, P. W. Serruys, J. R. T. C. Roelandt; How to assess regression of the atherosclerotic plaque. Biochem Soc Trans 1 August 1993; 21 (3): 642–647. doi: https://doi.org/10.1042/bst0210642 Download citation file: Ris (Zotero) Reference Manager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentAll JournalsBiochemical Society Transactions Search Advanced Search This content is only available as a PDF. © 1993 Biochemical Society1993 Article PDF first page preview Close Modal You do not currently have access to this content.

Temperature development in structural stainless steel sections exposed to fire

Decision making in asthma therapy—what is important in clinical practice?

P1645PCI or CABG in left main coronary artery disease: a comprehensive meta-analysis of adjusted observational studies and randomized controlled trials

No abstract is provided for this article.

The Clinical Consultation

PTCA : an investigational tool and a non-operative treatment of acute ischemia/ edited by Patrick W. Serruys, Rüdiger Simon, Kevin J. Beatt

No abstract is provided for this article.

Kink band propagation in layered structures

Accuracy of reported family histories of essential tremor

We studied the accuracy of reported family histories of essential tremor (ET) by questioning the patients in our clinic and subsequently by mail and phone.For individuals who continued to report a negative family history, we mailed a screening questionnaire to their first-degree relatives to further ascertain the presence of ET. On initial assessment, 67.7% of patients reported a positive family history of ET, but following all assessments, 96.0% of patients had a positive family history. We conclude that a negative family history of ET is often inaccurate, and that ET is primarily a hereditary disease. <b>NEUROLOGY 1996;47: </b> 264-265

Effectiveness of sirolimus-eluting stent implantation for the treatment of coronary artery disease in octogenarians

Sirolimus-eluting stent (SES) implantation has been shown to reduce repeat revascularization in various randomized trials. The present study evaluated the outcomes after SES implantation in 46 octogenarian patients. SES implantation in octogenarians appears to be feasible and is associated with very small subsequent need for repeat target vessel revascularization at 1 year.

Long term outcome after coronary stent implantation: a 10 year single centre experience of 1000 patients

<h3>OBJECTIVE</h3> To describe the long term clinical outcome (up to 11 years) after coronary stenting. <h3>DESIGN</h3> A single centre observational study encompassing 1000 consecutive patients with a first stent implantation (1560 stents) between 1986 and 1996, who were followed for at least one year with a median follow up of 29 months (range 12–132 months). <h3>RESULTS</h3> Up to July 1997 the cumulative incidence of the major adverse cardiac events (MACE) of death, non-fatal acute myocardial infarction, coronary artery bypass grafting, and repeat percutaneous transluminal coronary angioplasty was 8.2%, 12.8%, 13.1%, and 22.4%, respectively. Survival at one, three, and five years was 95%, 91%, and 86%, respectively. Comparison of MACE incidence during the "anticoagulant era" and the "ticlopidine era" revealed significantly improved event free survival with ticlopidine (27% <i>v</i>13%; p &lt; 0.005). Multivariable analyses showed that ejection fraction &lt; 50% (relative risk (RR) 4.1), multivessel disease (RR 3.0), diabetes (RR 2.9), implantation in saphenous vein graft (RR 2.1), indication for unstable angina (RR 1.9), and female sex (RR 1.7) were independent predictors of increased mortality after stenting. Independent predictors of any MACE were multivessel stenting (RR 2.0), implantation in saphenous bypass graft (RR 1.6), diabetes (RR 1.5), anticoagulant treatment (versus ticlopidine and aspirin) (RR 1.5), bailout stenting (RR 1.5), multivessel disease (RR 1.4), and multiple stent implantation (RR 1.5). <h3>CONCLUSIONS</h3> Long term survival and infarct free survival was good, particularly in non-diabetic men with single vessel disease and good ventricular function, who had a single stent implanted in a native coronary artery. A dramatic improvement was observed in event free survival, both early and late, with the replacement of anticoagulation by ticlopidine. This, of course, cannot be separated from improved stent implantation techniques between 1986 and 1995. Ultimately, almost 40% of the patients experienced an adverse cardiac event (mainly repeat intervention) in the long term. New advances in restenosis treatments and in secondary prevention must be directed at this aspect of patient management after stenting.

Relationship between monocyte-derived macrophage phagocytosis and airway inflammation in stable COPD

Despite increased numbers o f alveolar macrophages (mΦ) in stable COPD patients, lower airway bacterial colonisation (LABC) is often seen. We investigated the relationship between LABC status, airway inflammation & monocyte-derived mΦ (MDMs) phagocytosis. Whole blood & sputa were collected from stable COPD patients. MDMs were cultured & phagocytosis of fluorescently-labeled inert beads, or heat-killed Haemophilus influenzae (HI) & Streptococcus pneumoniae (SP) measured. Sputa were analysed by qPCR for HI, SP & Moraxella catarrhalis & airway cytokines by ELISA. Clinical characteristics are shown in Table 1. 19/40 patients had evidence of LABC on qPCR & had significantly higher levels of IL-8 and IL-1β, but not MPO, than non-LABC patients. There was a trend towards increasing airway inflammation with increasing bacterial load. Phagocytosis of HI & SP, but not beads, significantly increased with increasing airway IL-8 & IL-1β (Figure 1). There was no significant relationship between airway MPO and phagocytosis of any prey. Higher levels of airway IL-8 and IL-1β are associated with increased phagocytic response by MDMs to HI & SP but not beads. Higher bacterial loads seen in LABC patients may increase airway inflammation & this may in turn influence phagocytic ability.

S52 Association of microtubule instability with defective phagocytosis in COPD

<h3></h3> Acute exacerbations of COPD are the commonest cause of acute medical admissions in the UK and ∼50% are associated with bacterial infection. Alveolar macrophages (AM) normally clear inhaled bacteria but defective phagocytosis may lead to chronic colonisation and increased exacerbations. Monocyte-derived macrophages (MDM), used to model AM, were obtained from COPD, smoking and healthy subjects. MDM phagocytosis of fluorescently-labelled polystyrene beads, <i>Haemophilus influenzae</i> (HI) or <i>Streptococcus pneumoniae</i> (SP) was measured by fluorimetry. MDM derived from all subjects showed equivalent ability to phagocytose beads, however, COPD and smoker MDM showed significantly reduced phagocytosis of bacteria. Phagocytosis of HI was reduced by 28% and 48% in COPD and smoker MDM respectively, compared to healthy, while SP phagocytosis was reduced by 32% and 52% in COPD and smoker MDM respectively, compared to healthy (Abstract S52 table 1). Having identified defective bacterial phagocytosis in smoker and COPD MDM, the next step was to elucidate the underlying mechanism. Cytoskeletal rearrangement was investigated, with COPD MDM showing significantly reduced phagocytosis of bacteria in comparison to healthy after pre-incubation with nocodazole (microtubule disruptor). Microtubules are involved in membrane trafficking of the phagolysosome and microtubule stability is necessary for effective phagocytosis. Tubulin is acetylated to form stable microtubules and is deacetylated by HDAC6 and Sirt2. COPD MDM showed reduced levels of acetylated tubulin compared to healthy MDM. Pre-incubation with epothilone B (10 nm) a microtubule stabiliser, improved HI phagocytosis in COPD MDM by 20% (p&lt;0.05) and SP phagocytosis in smoker MDM by 40%. Levels of acetylated tubulin increased on exposure to bacteria alone in healthy and smoker MDM but not in COPD MDM. Pre-incubation with epothilone B was associated with significantly increased levels of acetylated tubulin in COPD cells. No significant differences were seen in the expression of HDAC6 or Sirt2 in COPD compared to healthy cells. MDM from smoking and COPD subjects show reduced phagocytosis of common respiratory bacterial pathogens. Acetylation of microtubules appears to be reduced in COPD, whereas, increasing tubulin acetylation is associated with improvements in phagocytosis, which may allow for targeted development of future therapies to treat colonisation and prevent exacerbations of COPD.

Increased sensitivity of the cough reflex in progressive systemic sclerosis patients with interstitial lung disease

Cough is a common presenting symptom of interstitial lung disease (ILD). The aim of this study was to examine the cough reflex in patients with progressive systemic sclerosis (PSS), with and without associated ILD. The cough reflex to inhalation of chloride deficient solutions and capsaicin was determined in patients with PSS with associated ILD (n=12), compared to patients with PSS without ILD (n=12). In addition, patients with a chronic dry cough (n=12) and healthy subjects (n=10) without cough were studied. Cough responses to inhalation of isotonic solutions containing 150, 75, 37.5 and 0 mM Cl- ions and of capsaicin (0.9-500 mM) were measured. PSS patients with ILD reported a significantly higher cough score than PSS patients without ILD (p<0.03). ILD patients coughed more than those without ILD to Cl- of 37.5 and 0 mM (19.1+/-5.0 vs 6.2+/-1.9 coughs x min(-1) (p<0.03), and 29.2+/-5.0 vs 14.1/-4.1 coughs x min(-1) (p<0.04), respectively). The log concentration of capsaicin causing two or five coughs was lower in PSS with ILD compared to PSS without ILD (0.74+/-0.15 mM vs 2.12+/-0.26 mM; p<0.002). Patients with chronic dry cough had a similar degree of response to low-chloride and capsaicin solutions as patients with PSS and ILD, whilst healthy controls had a similar degrees of response to PSS patients. There is an increased cough reflex in patients with interstitial lung disease, which may represent sensitization of airway sensory nerves. This may be the basis for the chronic dry cough in patients with interstitial lung disease.

Resveratrol, an extract of red wine, inhibits lipopolysaccharide induced airway neutrophilia and inflammatory mediators through an NF‐κB‐independent mechanism

Consumption of a naturally occurring polyphenol, resveratrol, in particular through drinking moderate amounts of red wine, has been suggested to be beneficial to health. A plethora of in vitro studies published demonstrate various anti-inflammatory actions of resveratrol. The aim of this research was to determine whether any of these anti-inflammatory effects translate in vivo in a rodent model of LPS induced airway inflammation. Resveratrol reduced lung tissue neutrophilia to a similar magnitude as that achieved by treatment with budesonide. This was associated with a reduction in pro-inflammatory cytokines and prostanoid levels. Interestingly, the reduction did not appear to be due to an impact on NF-kappaB activation or the expression of the respective genes as suggested by various in vitro publications. These results suggest that resveratrol may possess anti-inflammatory properties via a novel mechanism. Elucidation of this mechanism may lead to potential new therapies for the treatment of chronic inflammation.

Local buckling and ultimate strength of slender elliptical hollow sections in compression

The local buckling behaviour and ultimate cross-sectional strength of tubular elliptical profiles in compression is examined in this study through numerical modelling. The numerical models were first validated against previous experimental data with good agreement observed, enabling an extensive parametric study to be performed. A total of 270 elliptical sections were simulated in order to examine the influence of cross-section aspect ratio, geometric imperfections and local slendernesses. The obtained ultimate capacities, load–deformation responses and failure modes are discussed. It was found that for lower cross-section aspect ratios the behaviour of the elliptical hollow sections (EHS) was similar to that of cylindrical shells across a number of metrics; however, as the aspect ratio increased, more plate-like stable postbuckling behaviour was observed. Imperfection sensitivity was found to decrease with increasing slenderness and aspect ratio. The influence of the shape of the initial imperfection on the strengths of the EHS columns was also assessed and was found to be generally limited. Finally, a design method has been proposed for Class 4 EHS members that reflects the reduction in capacity due to local buckling with increasing slenderness, but also recognises the improved postbuckling stability with increasing aspect ratio; the proposals were shown to provide safe and accurate predictions for the strengths of the EHS columns with nondimensional local slendernesses up to 2.5 and aspect ratios from 1.1 to 5.0.

Neuropeptides and asthma