bluuebunny/crossref_metadata_2025 huggingface dataset:
Research and scholarship with impact: a British perspective
Authors: Thomas Rhodri
Published: June 2013

Purpose

This article aims to consider how academics might increase the impact of their research on practitioners.

Design/methodology/approach

The author draws on UK research council guidance and his experience of researching and working with practitioners to inform the discussion.

Findings

Maximising the impact of research on practitioners should not be a requirement. Issues that are critical to enhancing impact are highlighted for those who choose to see this as an important goal.

Originality/value

Research impact is becoming an increasingly prominent goal of research policy in the UK and elsewhere in the world but has not yet generated much discussion in the hospitality and tourism literatures.
Forming a long‐term industry‐university partnership
Authors: Pizam Abraham , Okumus Fevzi , Hutchinson Joe
Published: June 2013

Purpose

The purpose of this paper is to report on how the University of Central Florida's (UCF's) Rosen College of Hospitality Management (RCHM) has established a long‐term and successful partnership with the hospitality and tourism industry in Central Florida.

Design/methodology/approach

A case study approach was followed and the findings and examples reported in this paper were drawn from official documents and the authors' personal experiences.

Findings

The RCHM, one of the leading hospitality and tourism colleges in the world, has established and maintained successful partnerships with hospitality and tourism organizations in the Central Florida region. Over the years, industry partners have committed significant resources to the RCHM. In return, the RCHM has supported the industry by providing trained students and graduates, along with numerous research and consultancy projects. These successful partnerships were accomplished through mutual trust, an understanding of each other's needs and expectations, and successful collaboration between key industry owners/executives and senior administrators of the RCHM and UCF.

Research limitations/implications

This study implies that the establishment of strong partnerships between hospitality and tourism organizations and hospitality colleges requires college administrators to work closely with industry owners/executives to build mutual trust, personal friendships, and a common understanding of industry needs and expectations. Future studies may investigate similar successful industry‐university partnerships.

Practical implications

This study provides examples on how a hospitality college can form long‐term and successful partnerships with hospitality and tourism organizations.

Originality/value

There are few studies that provide evidence of successful partnerships between hospitality colleges and hospitality and tourism organizations.
Views from outside the academy
Authors: Thomas Rhodri
Published: June 2013

Purpose

The purpose of this paper is to gain an insight into the perspectives of a senior policy‐maker on university‐industry partnerships and, especially, on the utilisation of academic research in policy formation and evaluation.

Design/methodology/approach

An informal interview with Dr Leo Jago was undertaken via email. Dr Jago has recently been appointed as the Chief Economist for Tourism and General Manager of Tourism Research Australia (TRA). TRA is the branch of the Australian Government's Department of Resources, Energy and Tourism (RET) that provides statistics, research and analysis to support industry development, policy development and marketing for the Australian tourism industry. Dr Jago was previously a Professor of Tourism and Director of university research centres in Australia and the UK. For six years he was Deputy Chief Executive Officer and Director of Research for the Cooperative Research Centre for Sustainable Tourism (STCRC). He has published widely and is Co‐Editor of the International Journal of Event and Festival Management. Dr Jago also has 18 years' experience of owning and operating small and medium‐sized enterprises (SMEs) in the tourism sector.

Findings

The interview provides valuable lessons for researchers who wish to engage effectively with policy‐makers and other practitioners.

Originality/value

The transcript offers a rare opportunity to garner a more detailed understanding of the values, experiences and practices of this elite interviewee than is usually possible in academic publications.
Managing the tyranny of relevance: linking with industry – but not too much!
Authors: Lashley Conrad
Published: June 2013

Purpose

This paper aims to argue that hospitality educators need to develop courses that move away from the somewhat restricted programmes concerned almost exclusively with subjects deemed to be relevant to hospitality management. A more explicit concern with developing students' intellectual abilities will better serve both the industry and them as individuals. Fundamentally engagement with the study of hospitality through an array of science and social science disciplines will secure a more substantial foundation on which to study for hospitality management.

Design/methodology/approach

The paper reflects a number of pieces of research into the nature of hospitality management education and dominant learning styles on these programmes. It goes on to argue that programmes need to be designed to extend the curriculum beyond immediate management of hospitality business operations.

Findings

The paper argues that program design of hospitality management has tended to be dominated by a kind of tyranny of relevance where content has been almost exclusively focused on preparation for the world of work and careers in the management of hospitality operations. This dominant pragmatic agenda has been further compounded by the predominant activist learning styles of students. Without dismissing the need for programmes to prepare graduates for careers in the industry, it goes on to argue that program content should also aim to prepare participants to be critical thinkers by exposing them to content informed by social science.

Research limitations/implications

The paper advocates streams of study to be built into these programmes informed by social sciences and developing critical thinking.

Practical implications

The paper provides an analytical model to assist program designers and managers in developing participants who are philosophical practitioners.

Originality/value

The paper provides a model for understanding the principles needed to be used in the design of programmes in hospitality
Shifts in morphological and mechanical traits compensate for performance costs of reproduction in a wave‐swept seaweed
Authors: Demes Kyle W. , Harley Christopher D. G. , Anderson Laura M. , Carrington Emily
Published: June 2013

In addition to metabolic costs associated with reproduction, morphological and mechanical changes accompanying reproductive effort can affect an organism's performance. Reproductive effort may have unavoidable costs in plants and plant‐like taxa (i.e. extra mass or drag); however, the extent to which an organism can ameliorate these consequences by additional modifications of shape or tissue properties remains unknown in seaweed and plant taxa.

We investigated mechanical and morphological changes associated with reproduction and how these shifts influence functional performance in the winged kelp, Alaria marginata.

Compared to vegetative blades, reproductive blades were similar in width but were longer and had greater surface area. Reproductive sporophylls were also thicker and less ruffled. Tissue extensibility and breaking stress were not different in reproductive vs. vegetative blades. However, reproductive tissue exhibited greater tensile stiffness, flexural stiffness and force to break.

Reproductive blades experienced greater drag (despite decreased flapping) than did vegetative blades, but did not experience greater size‐specific drag. Tissues cut into experimental blades of the same size and shape experienced greater drag when cut from reproductive tissue suggesting that the change in shape associated with the onset of reproduction ameliorates the cost of increased tissue stiffness. Nonetheless, increased blade breaking force in reproductive individuals resulted in increased blade safety factors (breaking force/drag experienced) in reproductive compared to non‐reproductive sporophylls.

Synthesis: In A. marginata, decreased flexibility and increased surface area are mechanical costs associated with reproduction. Decreased blade ruffliness and increased strength associated with the onset of reproduction in A. marginata ameliorate the concomitant mechanical costs of decreased flexibility and increased size. Shifts in mechanical and morphological traits among plants and plant‐like taxa may allow them to increase reproductive output without decreasing functional performance.
Future Shock or Future Stability?: Generational Change and the Australian Party System
Authors: Martin Aaron , Pietsch Juliet
Published: June 2013

The stability of the Australian two‐party system has been a long‐running feature of Australian politics. But a question outstanding in the literature is how different generations of Australians contribute to the stability of the Australian two‐party system and how this has changed over time. In answering this question, this article sheds light on generational effects and party system change that better informs us about the sources of voting patterns over a long period of time. Further, this article draws on and builds on the international literature on generations and party systems.
Trains, Plains and Automobiles: New South Wales Political Debates (1985) and the Invention of Western Sydney
Authors: Hutchinson Mark
Published: June 2013

There has recently been conjecture as to the decline of the major political traditions and the rise of a more fragmented politics in Australian cities. This paper uses a “slice history” approach to explore the evolving concept of “the West” in Sydney, New South Wales, its place in public debate, and the interplay between centre and periphery during the single “axial” year of 1985. New South Wales Legislative Assembly debates are tabulated, analysed and discussed in the context of larger government programs and public debates. The paper concludes that the concept of “The West”, while of vital political importance in both state and Federal politics, is an elusive term which has been used in unreflective, and often self‐defeating, ways by those tasked with providing the region with services.
Severe drug‐induced anaphylaxis: analysis of 333 cases recorded by theAllergyVigilanceNetwork from 2002 to 2010
Authors: Renaudin J.‐M. , Beaudouin E. , Ponvert C. , Demoly P. , Moneret‐Vautrin D.‐A.
Published: June 2013

Background

A few series of well‐documented cases of severe drug‐induced anaphylaxis (SDA) are available.

Methods

Cases collected by theAllergyVigilanceNetwork from 2002 to 2010 were analyzed for clinical signs, causative drugs, and efficacy of a stepwise approach to diagnosis, using skin tests, laboratory tests, and oral challenges.

Results

Three hundred and thirty‐three cases concerned 300 adults (90.1%) and 33 children (9.9%): 206 females (61.9%) and 127 males (38.1%). Mean age was 42.7 ± 18 years. Anaphylactic shock (76.6%), severe systemic reactions (10.5%), acute laryngeal edema (9%), severe bronchospasm (2.1%), and six fatal cases (1.8%) were recorded. There were 270 cases (81.1%) of ambulatory anaphylaxis. Sixty‐three cases (18.9%) occurred during anesthesia. Hospitalization was required in 94.8% of cases. 23.7% of patients were admitted to an intensive care unit. Epinephrine was used in 57.9% of cases. Eighty‐four drugs were incriminated: antibiotics (49.6%), muscle relaxants, latex and anesthetics (15%), nonsteroidal anti‐inflammatory drugs (10.2%), acetaminophen (3.9%), iodinated or magnetic resonance imaging contrast media (4.2%), immunotherapy and vaccines (3.9%), and other drugs (13%). Among antibiotics, amoxicillin (97 cases), other penicillins (four cases), cephalosporins (41 cases), quinolones (15 cases), and pristinamycin (seven cases) were the most common. The diagnosis of drug hypersensitivity was obtained by skin tests in 72.9%, laboratory tests only in 2.4% of cases, and oral challenges (OCs) only in 3.9% of cases.

Conclusions

Three hundred and thirty‐three case reports provided data on drugs involved in severe anaphylaxis. The efficacy of skin tests and poor use of laboratory tests are underlined. Further progress may depend on OCs.
The consequences of not having eosinophils
Authors: Gleich G. J. , Klion A. D. , Lee J. J. , Weller P. F.
Published: June 2013

Several lines of evidence suggest that deficiency of eosinophils is not associated with any characteristic abnormality. Patients lacking eosinophils, in the setting of immunodeficiency or as a consequence of IgG‐mediated eosinophil precursor destruction, do not display any distinguishing abnormalities related to eosinophil reduction. The observation that eosinophil‐deficient mice do not display any distinctive syndrome or failure of their health is evidence that, under ordinary laboratory conditions, the eosinophil does not play a critical role in the well‐being of mammals. Observations that monoclonal antibodies to interleukin‐5 (IL‐5) are well tolerated appear unsurprising in light of these findings. For example, patients with the hypereosinophilic syndrome have received mepolizumab, an anti‐IL‐5 monoclonal antibody, for as long as 6 years and have not developed any characteristic set of adverse events. Safety data for reslizumab, another anti‐IL‐5 monoclonal antibody, and benralizumab, a monoclonal antibody to the IL‐5 receptor α‐chain, are comparatively limited, especially for benralizumab, although reports of administration of these antibodies to humans suggest that they are well tolerated. Thus, data to the present suggest that reduction of eosinophils appears to have no characteristic ill effects on normal health, and monoclonal antibodies that deplete eosinophils have the potential to be widely employed in the treatment of eosinophil‐associated diseases.
In Vitro Shear Stress‐Induced Platelet Activation: Sensitivity of Human and Bovine Blood
Authors: Lu Qijin , Hofferbert Bryan V. , Koo Grace , Malinauskas Richard A.
Published: June 2013

As platelet activation plays a critical role in physiological hemostasis and pathological thrombosis, it is important in the overall hemocompatibility evaluation of new medical devices and biomaterials to assess their effects on platelet function. However, there are currently no widely accepted in vitro test methods to perform this assessment. In an effort to develop effective platelet tests for potential use in medical device evaluation, this study compared the sensitivity of platelet responses to shear stress stimulation of human and bovine blood using multiple platelet activation markers. Fresh whole blood samples anticoagulated with heparin or anticoagulant citrate dextrose, solution A (ACDA) were exposed to shear stresses up to 40 Pa for 2 min using a cone‐and‐plate rheometer model. Platelet activation was characterized by platelet counts, platelet surface P‐selectin expression, and serotonin release into blood plasma. The results indicated that exposure to shear stresses above 20 Pa caused significant changes in all three of the platelet markers for human blood and that the changes were usually greater with ACDA anticoagulation than with heparin. In contrast, for bovine blood, the markers did not change with shear stress stimulation except for plasma serotonin in heparin anticoagulated blood. The differences observed between human and bovine platelet responses suggest that the value of using bovine blood for in vitro platelet testing to evaluate devices may be limited.
On the Origin of the Green Colour of Archaeological Bone Artefacts of the Gallo‐Roman Period
Authors: Ferrand J. , Rossano S. , Rollet Ph. , Allard T. , Cordier P. , Catillon G. , Auxiette G. , Farges F. , Pont S.
Published: June 2013

Recent findings in the city of Reims have lead to the discovery of manufactured bone objects coloured in green throughout their entire volume. In order to discover the intentional nature of the colouration and to propose a colouration mechanism, modern ox bones have been coloured in the laboratory. Bones with a hue similar to that of the archaeological artefacts have been obtained by boiling in an acidic brine in a copper vessel. A combination of infrared spectroscopy, X‐ray diffraction and transmission electron microscope observations did not reveal the speciation of copper, but allowed us to validate the colouration process and to discuss the intentional origin of the colouration.
Vertical Trade Maps
Authors: Ferrarini Benno
Published: June 2013

We develop a method to map global network production and vertical trade. Based on product‐level trade data across a matrix of 75 countries, an index measures the intensity of bilateral vertical trade and a force‐directed algorithm lays it out for visualization as a world map of production networks. Three major hubs in the global networks are identified: theUSA,Germany andChina–Japan. Outside Asia and apart from Mexico, mainly because of its maquiladoras network ties to theUSA, we find that developing countries are not yet fully part of the global production networks.
Wage Effects of Employment Protection Legislation inTaiwan
Authors: Lin Yen‐Ling
Published: June 2013

This study investigates the effects of employment protection on wages. The implementation of employment protection legislation increases employers' firing costs and reduces labor turnover, and, therefore, results in lower wages. Our empirical results show that the implementation ofTaiwan's leads to a reduction in wages, the effects of which varies with the stringency of the law's enforcement. In addition, employment protection can lead to a decrease in wage dispersion, implying the worsening of job matches.
CD27+ B cells from a subgroup of common variable immunodeficiency patients are less sensitive to apoptosis rescue regardless of interleukin-21 signalling
Authors: Clemente A , Pons J , Lanio N , Matamoros N , Ferrer J M
Published: June 2013

Common variable immunodeficiency (CVID) is a primary immunodeficiency characterized by hypogammaglobulinaemia and recurrent infections. Although the underlying cause is unknown, B cells from most CVID patients fail to differentiate to memory or plasma cells. We investigated if increased apoptosis could influence the fate of B cells. For this purpose we activated purified B lymphocytes of CVID patients with a surrogate T-dependent (anti-CD40) or T-independent [cytosine–phosphate–guanosine oligodeoxynucleotides (CpG-ODN) or anti-immunoglobulin (Ig)M)] stimulus with or without interleukin (IL)-21. We found that CD27+ B cells were more sensitive than CD27– B cells to spontaneous apoptosis and less sensitive to rescue from apoptosis. The addition of IL-21 down-modulated the protective effect of all the stimuli on CD27– B cells and the protective effect of CpG-ODN and anti-IgM on CD27+ B cells. In contrast, IL-21 rescued unstimulated CD27– B cells and improved the rescue of anti-CD40-stimulated CD27+ B cells. When we compared patients and controls, mainly CD27+ B cells from MB0 patients were less sensitive to rescue from apoptosis than those from MB1 patients and controls after activation, irrespective of the IL-21 effect. Increased apoptosis during an immune response could result in lower levels of immunoglobulin production in these patients.
Relationship of CD146 expression to activation of circulating T cells: exploratory studies in healthy donors and patients with connective tissue diseases
Authors: Hadjinicolaou A V , Wu L , Fang B , Watson P A , Hall F C , Busch R
Published: June 2013

The endothelial cell adhesion molecule, CD146, is expressed on ≈ 2% of normal circulating T cells, correlating with T cell activation, endothelial interactions and T helper type 17 (Th17) effector functions. In this study, we have characterized CD146 expression in circulating T cells from healthy controls and patients with stable, well-controlled autoimmune connective tissue diseases (CTDs). In vitro, anti-CD3/anti-CD28 stimulation induced CD146 expression in both CD4 and CD8 T cells. In healthy controls and CTD patients, CD146 was associated with expression of recent and chronic activation markers (CD25+, OX-40+, CD69+, CD27–) and was confined to CD45RO+/RA–/CD28+ populations within the CD4 subset. Except for CD69, these markers were not associated with CD146 in the CD8 subset. Surprisingly, most CTD patients exhibited no T cell hyperactivation ex vivo. In five of five patients with secondary Sjögren's syndrome circulating T cells appeared activated despite therapy, and CD146 up-regulation, associated with activation markers, was observed both on CD4 and CD8 T cells. There was no association between CD146 and putative pro-atherogenic T cell subsets. In conclusion, the relationship of CD146 expression to T cell activation differs between T cell subsets in healthy subjects and correlates with systemic hyperactivity, where present, in patients with CTDs, as exemplified by the patients with secondary Sjögren's syndrome in this study.
Evolution of attachment structures in the highly diverse Acercaria (Hexapoda)
Authors: Friedemann Katrin , Spangenberg Rico , Yoshizawa Kazunori , Beutel Rolf G.
Published: June 2013

Acercaria display an unusually broad array of adhesive devices occurring on different parts of the legs. Attachment structures of all major subgroups are described and illustrated. Nineteen characters of the distal leg region were combined with a data matrix containing 99 additional morphological characters of different body parts. The results of the cladistic analysis are largely congruent with current hypotheses. Zoraptera are not retrieved as close relatives of Acercaria. The monophyly of the entire lineage and of the major subgroups Psocodea, Phthiraptera, and Hemiptera is confirmed. Our data also support the monophyly of Auchenorrhycha and a sister‐group relationship between Thysanoptera and Hemiptera (Condylognatha). In contrast to other lineages of insects, the hairy type of adhesive device is present only in one group within the Acercaria (Heteroptera, Cimicomorpha). The arolium is present in the groundplan but missing in several groups (e.g. Psocodea, Cicadoidea, Aphidoidea). Pretarsal pulvilli evolved several times independently. Tarsal euplantulae and different specialized clasping devices have evolved within Phthiraptera, whereas pretarsal attachment devices are missing in this ectoparasitic group. The potential to modify pretarsal attachment devices in their structural details has probably contributed to the very successful diversification of the predominantly phytophagous Hemiptera.
No Plan B: But is There a ‘Third Way'?
Authors: Matthews Kent
Published: June 2013

This paper reviews the argument for a slowdown in the fiscal consolidation policy of the UK government. It reviews the existing literature and the evidence of the interwar period in the UK where a recovery occurred without a relaxation of the tight fiscal regime of the period. It argues that even in a zero‐lower‐bound, the evidence for a plan B is weak. Given that there may have been significant capacity destruction, the paper suggests a third way that calls for a supply‐side framework that sets the condition for an improvement in long‐term growth and productivity.
The Economics of Minimum Pricing for Alcohol
Authors: Craven Barrie M. , Marlow Michael L. , Shiers Alden F.
Published: June 2013

This article explores a wide range of issues that proponents of setting minimum prices for alcohol must resolve before they can safely claim their proposals improve public health and decrease public health care costs. Problems range from inability to know ‘correct’ prices and why tacking on pricing regulations to markets already taxed makes sense, to various unintended adverse consequences such as generating higher demand for illegal drugs and alcohol. It also remains unclear why advocates would not prefer to raise taxes since this is the typical method that economists propose to correct markets in which harm spills over to innocent parties.
Challenging The Spirit Level: Is There Really a Relationship between Inequality and Obesity?
Authors: Zala Darshan
Published: June 2013

This paper examines the proposition, set out in The Spirit Level, that inequality is associated with high levels of obesity. It reviews existing literature and uses British Household Panel Survey data to study how district‐level and regional‐level income inequality is related to obesity in the UK. This is likely to be the first study of its type that uses individual‐level data that is representative of the UK population. We find little evidence to support policies that reduce income inequality with the aim of reducing obesity levels in the UK.
Does the Lisbon Treaty Effectively Limit the Power of the European Union?
Authors: Ciclet Émilie
Published: June 2013

Although the Lisbon Treaty recognises the necessity to limit the power of the European Union, some of its limitations are poorly expressed. As a result, the European Commission has the possibility to act arbitrarily by expanding Union power. The position of the Commission is pre‐eminent, notably with respect to the drafting of EU measures. Not only can the Commission expand Union power, but it may also favour certain actors at the expense of the principals (Member States and their citizens). Indeed, the Commission may apply definitions of the ‘common European interest’ that go beyond the preferences of the principals.
Validation of Two‐Dimensional Methods for Left Atrial Volume Measurement: A Comparison of Echocardiography with Cardiac Computed Tomography
Authors: Al‐Mohaissen Maha A. , Kazmi Mustapha H. , Chan Kwan Leung , Chow Benjamin J.W.
Published: June 2013

Background

Left atrial volume (LAVol) is an important predictor of cardiovascular outcomes. Different formulas are applied to calculate LAVol using two‐dimensional transthoracic echocardiography (2DTTE) with variable reference values. The objective of the study was to evaluate the accuracy of methods to calculate LAVol by 2DTTE or cardiac computed tomography (CT).

Methods and Results

Overall 177 consecutive patients who underwent both a 2DTTE and retrospective electrocardiogram (ECG)‐gated coronary CT angiography (CTA) within 15 days were included for this study. LA volume measurements were calculated by 2DTTE and 2DCT using the biplane area‐length, biplane Simpson's, prolate‐ellipsoid‐1 and prolate‐ellipsoid‐2 methods. These results were compared with those measured by CT using a volumetric method. There was very good correlation between the CT and echocardiographic measures for LAVol, but significant underestimation of the echocardiographic methods when compared to the reference standard (33.5%, 39.1%, 48.1%, and 53.2% for the biplane area‐length, biplane Simpson's, prolate‐ellipsoid‐1, and prolate‐ellipsoid‐2 methods, respectively). The biplane area‐length method using 2DTTE had the closest volume estimation of all echocardiographic methods to the reference standard (67.6 ± 25.5 mL vs. 106 ± 35.5 mL, r = 0.712). Similarly, the biplane area‐length method using CT most accurately predicted LAVol (103.3 ± 36.0 mL, r = 0.965).

Conclusions

Compared to CT, 2DTTE provides reasonable assessment of LAVol, although all measurement methods underestimate LAVol. For both 2DTTE and CT, the biplane area‐length method appears to provide the most accurate 2D estimate of LAVol.
Impact of Atrioventricular Compliance on Clinical Outcome of Patients Undergoing Successful Percutaneous Balloon Mitral Valvuloplasty
Authors: Mahfouz Ragab A , Elawady Waled , Hossein Ekhlas , Yosri Ahmad
Published: June 2013

Objective

We aimed to assess the impact of atrioventricular compliance (Cn) on the clinical outcome, after successful percutaneous balloon mitral valvuloplasty (PBMV).

Methods and Results

Using Doppler echocardiography Cn was estimated from the equation that has been previously validated. Mitral valve area (MVA), tricuspid annular plane systolic excursion (TAPSE), pulmonary artery pressure (PAP), and degree of tricuspid regurgitation (TR) severity were evaluated before, immediately, and every 6 months with a median duration of 32 months after successful PBMV in 150 consecutive patients. An immediate drop in PAP and significant improvement of right ventricle (RV) function was observed after PBMV. Cn was negatively correlated pre and post‐PBMV, with the degree of pulmonary artery systolic pressure (PAPs), TAPSE (P < 0.0001). Patients with Cn ≤ 3.75 mL/mmHg had higher incidence of adverse outcome (developing atrial fibrillation [AF], worsening RV function, progressive left atrial dilation, and redo intervention). Multivariate regression analysis showed that the Cn was the strongest independent predictor of PAPs and RV function before and after successful PBMV (P < 0.0001). Cn ≤ 3.75 mL/mmHg was the cutoff value for prediction of clinical events at follow‐up.

Conclusions

Atrioventricular compliance was significantly lower in patients with mitral stenosis (MS) with unfavorable outcome after successful PBMV. The RV function and pulmonary hypertension were significantly correlated with the degree of Cn. This suggests a significant role of Cn in patients with MS, providing a good insight for intervention and utilizing Cn as a noninvasive hemodynamic index for risk stratification and proper timing for intervention in patients with MS.
Evaluation of Correlation between Aortic Elastic Parameters and Atrial Electromechanical Abnormalities in Hypertensive Patients
Authors: Sen Omer , Abali Gulcan , Yavuz Bunyamin , Batur Mutafa Kemal
Published: June 2013

Objectives

Arterial hypertension leads to instability and heterogeneity in atrial conduction by these hemodynamic and morphological changes in heart and aorta. These changes can be evaluated by transthoracic echocardiography. The aim of this study was to evaluate the correlation of aortic elastic parameters and atrial electromechanical delay (AEMD) parameters in patients with hypertension.

Methods

Eighty‐one hypertensive patients and 55 control subjects were included in the study. All subjects underwent transthoracic echocardiography for detecting aortic elastic parameters and AEMD parameters.

Results

There was no difference between HT and control groups regarding age and gender. Aortic strain (8.1 ± 4.3% vs. 10.3 ± 5.1%, P = 0.008) and aortic distensibility (0.35 ± 0.18 cm2/dyn vs. 0.45 ± 0.23 cm2/dyn, P = 0.003) were decreased in hypertensive patients than in controls. Intra‐left AEMD (25.5 ± 7.3 vs. 21.8 ± 9.2 P < 0.009) was significantly higher in hypertensive patients compared to control subjects. No statistically significant difference was found in intra‐right AEMD and inter‐AEMD between the groups. There was a positive significant moderate correlation between aortic strain and intra‐left AEMD (r = 0.501, P < 0.001).

Conclusions

This study demonstrated that intra‐left AEMD was increased in hypertensive patients and aortic elastic parameters was correlated with intra‐left AEMD. These findings may be related to similar structural and functional changes in heart and aorta in hypertension.
Age‐ and Gender‐Dependent Left Ventricular Remodeling
Authors: Gebhard Catherine , Stähli Barbara E. , Gebhard Caroline E. , Tasnady Hanna , Zihler Deborah , Wischnewsky Manfred B. , Jenni Rolf , Tanner Felix C.
Published: June 2013

Background

The effect of age and gender on left ventricular (LV) size, muscle mass, and systolic function as determined by two‐dimensional echocardiography has not yet been investigated in a large population.

Methods

Normal transthoracic two‐dimensional echocardiography studies of 5307 subjects (47% males) performed between March 1990 and December 2011 were analyzed. LV end‐diastolic volume index (LVEDVI), LV muscle mass index (LVMMI), LV ejection fraction (LVEF), and LV fractional shortening (LVFS) were compared in different age groups.

Results

LVMMI increased in females from 66.4 ± 1.3 g/m2 (7–20 years) to 76.3 ± 0.9 g/m2 (60–80 years; P < 0.0001) and in males from 81.9 ± 1.7 g/m2 (7–20 years) to 94.6 ± 1.3 g/m2 (60–80 years; P < 0.0001). LVEDVI decreased in females from 49.8 ± 0.9 mL/m2 (7–20 years) to 42.8 ± 0.6 mL/m2 (60–80 years; P < 0.0001) and in males from 56.6 ± 0.8 mL/m2 (7–20 years) to 49.0 ± 0.7 mL/m2 (60–80 years; P < 0.0001). A significant increase in LVEF was observed with age (P < 0.0001 for both genders), but it was more pronounced in females (62 ± 0.5% [age 7–20 years] vs. 65 ± 0.3% [age 60–80 years]) than in males (62 ± 0.5% [age 7–20 years] vs. 64 ± 0.3% [age 60–80 years]). Similarly, LVFS increased in females from 37.7 ± 0.5% (7–20 years) to 42.4 ± 0.4% (60–80 years; P < 0.001) and in males from 37.3 ± 0.5% (7–20 years) to 39.4 ± 0.5% (60–80 years; P < 0.001).

Conclusions

LVEF, LVFS, and LVMMI increase with advancing age, in particular in females. In contrast, LVEDVI decreases with age. These findings indicate that the LV undergoes a lifelong remodeling.
Altered Mitral Inflow Orifice in Severe Aortic Regurgitation: Real Time Three‐Dimensional Echocardiographic Findings
Authors: Bertrand Philippe B. , Verhaert David , Vandervoort Pieter
Published: June 2013

Mini‐Abstract

We present the case of a young man with severe eccentric aortic regurgitation, obstructing mitral inflow and provoking an audible Austin Flint murmur at clinical examination. Two‐dimensional color Doppler echocardiography depicts the remarkable mechanical interaction between aortic regurgitant jet and anterior mitral leaflet opening. Three‐dimensional transesophageal echocardiography aids in understanding the geometric and hemodynamic consequences of the regurgitant jet and in the genesis of the Austin Flint murmur. This case accentuates the incremental value of three‐dimensional echocardiography when evaluating valvular pathology, and offers more insight in the interaction between aortic regurgitant flow and mitral leaflet dynamics.
Bleeding Risk in Patients with Esophageal Varices Undergoing Transesophageal Echocardiography
Authors: Pantham Ganesh , Waghray Nisheet , Einstadter Douglas , Finkelhor Robert S. , Mullen Kevin D.
Published: June 2013

Background

Bleeding from esophageal varices is a major potential concern during transesophageal echocardiography (TEE) in patients with cirrhosis of the liver. As there are limited data on its risk in these patients, this was retrospectively assessed at our institution.

Methods

The hospital electronic medical record database at our university affiliated teaching hospital was searched for all patients with esophageal varices undergoing TEE from 2000 to 2012 and patient charts were reviewed for procedure‐related bleeding complications.

Results

Twenty‐four patients with esophageal varices were found (18 men, 57 ± 14 years). Nine patients had grade 2 esophageal varices, 15 patients had grade 1 varices, and 12 patients had portal hypertensive gastropathy. Alcoholic liver disease (9) and hepatitis C (8) were the most common etiologies of the cirrhosis with an average MELD score of 15. The most common indication for TEE was for possible endocarditis (15). Medications potentially increasing bleeding risk included warfarin in 2 and aspirin in 7 patients. Twelve patients were taking β‐blockers for portal hypertension. There were no immediate bleeding complications and none of these patients were readmitted with bleeding.

Conclusions

TEE can be performed without serious bleeding risk in patients with grade 1 or 2 esophageal varices.
Coronary Flow Reserve and Myocardial Performance Index in Newly Diagnosed Diabetic Patients
Authors: Kalkan Gülhan Yüksel , Gür Mustafa , Şahin Durmuş Yıldıray , Baykan Ahmet Oytun , Elbasan Zafer , Kuloğlu Osman , Kıvrak Ali , Türkoğlu Caner , Arık Osman Ziya , Çayli Murat
Published: June 2013

Background

Patients with diabetes mellitus (DM) are at high risk of left ventricular (LV) dysfunction. A reduction of coronary flow reserve (CFR) has been demonstrated in diabetic patients without coronary artery stenosis. In this study, we investigated the association between LV myocardial diastolic and systolic functions and the CFR in newly diagnosed diabetic patients in the absence of coronary artery disease.

Method

We studied 88 patients (mean age 49 ± 10 years) with newly diagnosed DM and 40 healthy control subjects (mean age 50 ± 9 years). All subjects underwent transthoracic echocardiography. The myocardial performance index (MPI) was determined by using pulsed‐wave Doppler. The CFR was calculated as the hyperemic to resting coronary diastolic peak velocities ratio.

Results

Patients with diabetes had significantly longer mitral E‐wave deceleration time and higher MPI value than control group (P = 0.023 and P < 0.001, respectively). The mean CFR was lower in diabetic patients compared with controls (P = 0.001). The MPI was significantly correlated with CFR (r = −0.371, P < 0.001), LV ejection fraction (r = −0.274, P = 0.018) E/A ratio (r = −0.244, P = 0.024), and glycosylated hemoglobin (HbA1c) (r = 0.476, P < 0.001). Multivariate regression analysis showed that MPI was independently associated with CFR (β = −0.292, P < 0.0001) and HbA1c level (β = 0.372, P < 0.0001).

Conclusions

The MPI was independently associated with CFR in newly diagnosed diabetic patients. The decrease in CFR may cause LV systolic and diastolic dysfunction in asymptomatic diabetic patients.
Spontaneous Echo Contrast at a Large Inter‐Atrial Septal Aneurysm
Authors: Pratap Pravin , Foster Mariah M. , Labovitz Arthur J. , Chae Sanders H.
Published: June 2013

Mini‐Abstract

A 75‐year‐old woman presented with typical atrial flutter. Prior to ablation, a transesophageal echocardiogram demonstrated significant spontaneous echo contrast (SEC) at the site of a large inter‐Atrial septal aneurysm (ASA). After ablation of the arrhythmia, recovery of her left ventricular function, and 3 months of therapeutic anticoagulation with warfarin, she continued to have significant SEC at the site of her ASA, implicating the ASA as the source for the SEC.
Modulation of presynaptic Ca2+ currents in frog motor nerve terminals by high pressure
Authors: Aviner Ben , Gradwohl Gideon , Moore Homer J. , Grossman Yoram
Published: June 2013

Presynaptic Ca2+‐dependent mechanisms have already been implicated in depression of evoked synaptic transmission by high pressure (HP). Therefore, pressure effects on terminal Ca2+ currents were studied in Rana pipiens peripheral motor nerves. The terminal currents, evoked by nerve or direct stimulation, were recorded under the nerve perineurial sheath with a loose macropatch clamp technique. The combined use of Na+ and K+ channel blockers, [Ca2+]o changes, voltage‐dependent Ca2+ channel (VDCC) blocker treatments and HP perturbations revealed two components of presynaptic Ca2+ currents: an early fast Ca2+ current (ICaF), possibly carried by N‐type (CaV2.2) Ca2+ channels, and a late slow Ca2+ current (ICaS), possibly mediated by L‐type (CaV1) Ca2+ channels. HP reduced the amplitude and decreased the maximum (saturation level) of the Ca2+ currents, ICaF being more sensitive to pressure, and may have slightly shifted the voltage dependence. HP also moderately diminished the Na+ action current, which contributed to the depression of VDCC currents. Computer‐based modeling was used to verify the interpretation of the currents and investigate the influence of HP on the presynaptic currents. The direct HP reduction of the VDCC currents and the indirect effect of the action potential decrease are probably the major cause of pressure depression of synaptic release.
Multiple episodes of sodium depletion in the rat: a remodeling of the electrical properties of median preoptic nucleus neurons
Authors: Voisin Aurore N. , Mouginot Didier , Drolet Guy
Published: June 2013

In rat brain, the detection and integration of chemosensory and neural signals are achieved, inter alia, by the median preoptic nucleus (MnPO) during a disturbance of the hydromineral balance. This is allowed through the presence of the sodium (Na+) sensor neurons. Interestingly, enkephalins and mu‐opioid receptors (μ‐ORs) are known for their role in ingestive behaviors and have previously been shown to regulate the excitability of MnPO neurons following a single Na+ depletion. However, little is known about the role of these μ‐ORs in the response enhancement following repeated Na+ challenge. Therefore, we used whole‐cell recordings in acute brain slices to determine neuronal plasticity in the electrical properties of the MnPO Na+ sensor‐specific neuronal population following multiple Na+ depletions. Our results show that the population of Na+ sensor neurons was represented by 80% of MnPO neurons after a single Na+ depletion and was reduced after three Na+ depletions. Interestingly, the subpopulation of Na+ sensors responding to D‐Ala2,N‐MePhe4,Gly‐ol‐enkephalin (DAMGO), a specific μ‐OR agonist, represented 11% of MnPO neurons after a single Na+ depletion and the population doubled after three Na+ depletions. Moreover, Na+ sensor neurons displayed modifications in the discharge pattern distribution and shape of calcium action potentials after three Na+ depletions but these changes did not occur in Na+ sensors responding to DAMGO. Thus, the reinforced μ‐OR functionality in Na+ sensors might take place to control the neuronal hyperexcitability and this plasticity in opioid‐sensitive and Na+ detection MnPO networks might sustain the enhanced salt ingestion induced by repeated exposure to Na+ depletion.
Turnover and availability of soil organic carbon under differentMediterranean land‐uses as estimated by13Cnatural abundance
Authors: Novara A. , Gristina L. , Kuzyakov Y. , Schillaci C. , Laudicina V. A. , La Mantia T.
Published: June 2013

Soil organic matter (SOM) is an important factor in ecosystem stability and productivity. This is especially the case for Mediterranean soils suffering from the impact of human degradation as well as harsh climatic conditions. We used the carbon (C) exchange resulting fromC3‐C4andC4‐C3vegetation change under field conditions combined with incubations under controlled conditions to evaluate the turnover and availability of soil organicCunder different land‐uses. The 40‐year succession ofHyparrenia hirtaL. (C4photosynthesis) after more than 85 years of olive tree (Olea europaeaL.;C3photosynthesis) growth led to the exchange of 54% of soil organic C fromC3toC4forms. In contrast, 21 years of vine (Vitis viniferaL.) growing afterH. hirtadecreased the organic C content to 57%. Considering this exchange and decrease as well as the periods after the land‐use changes, we calculated the mean residence time (MRT) of soil C of different ages. TheMRTof C under grassland dominated byH. hirtawas about 19 years, but was 180 years under the vineyard. The rates of C accumulation under theH. hirtagrassland were about 0.36 Mg C ha−1 year−1. In contrast, the rates ofClosses after conversion from natural grassland to a vineyard were 1.8 times greater and amounted to 0.65 Mg C ha−1 year−1. We conclude that changes of land use from naturalMediterranean grassland to a vineyard lead to very largeClosses that cannot be compensated for over the same periods.
Noninvasive determination of atrial fibrillation cycle length by atrial colour tissue Doppler imaging in horses
Authors: Decloedt A. , de Clercq D. , van der Vekens N. , Verheyen T. , van Loon G.
Published: June 2013

Reasons for performing study

Atrial fibrillation cycle length (AFCL) is an indicator of atrial electrical remodelling during atrial fibrillation (AF).

Objectives

To compare AFCL measured invasively from an intra‐atrial electrogram (AFCLEGM) with AFCL measured noninvasively by atrial colour tissue Doppler imaging (AFCLTDI).

Study design

Prospective descriptive clinical study.

Methods

Measurements were performed in 31 episodes of AF or flutter in 29 horses (588 ± 61 kg bwt, 9 ± 3 years old) admitted for transvenous electrical cardioversion. The AFCLEGM was measured from an intracardiac electrogram using a bipolar sensing/pacing electrode inserted into the right atrium. The AFCLTDI was measured from atrial colour tissue velocity curves in the following 5 regions: 1) left atrial free wall from a right parasternal 4‐chamber view, 2) left atrial free wall from a short‐axis view, 3) left atrial free wall from a left parasternal long‐axis view, 4) interatrial septum, and 5) right atrial dorsal wall near the tuberculum intervenosum. The AFCLEGM and AFCLTDI from the 5 regions were compared using a one‐way repeated‐measures ANOVA with Bonferroni correction for multiple comparisons and calculation of the Bland‐Altman mean bias and limits of agreement of AFCLEGM and AFCLTDI.

Results

The AFCLEGM was 161 ± 18 ms in 29 AF episodes. Two horses showed atrial flutter and had an AFCLEGM of 244 and 324 ms. The mean bias between AFCLTDI and AFCLEGM ranged from ‐18 to +9 ms depending on the atrial wall region. The AFCLTDI was significantly shorter in the left atrial free wall from the right parasternal 4‐chamber view and short‐axis view than in the other regions (P<0.001).

Conclusions

Tissue Doppler imaging allows noninvasive measurement of AFCL in horses with AF and is able to identify spatial differences within the equine atria. Atrial fibrillation cycle length is an indicator of atrial electrical remodelling and is an important parameter to study AF pathophysiology or the effect of antiarrhythmic drugs.
Structure and mechanism of non‐histone protein acetyltransferase enzymes
Authors: Friedmann David R. , Marmorstein Ronen
Published: June 2013

Post‐translational modification of proteins is ubiquitous and mediates many cellular processes, including intracellular localization, protein–protein interactions, enzyme activity, transcriptional regulation and protein stability. While the role of phosphorylation as a key post‐translational modification has been well studied, the more evolutionarily conserved post‐translational modification acetylation has only recently attracted attention as a key regulator of cellular events. Protein acetylation has been largely studied in the context of its role in histone modification and gene regulation, where histones are modified by histone acetyltransferases to promote transcription. However, more recent acetylomic and biochemical studies have revealed that acetylation is mediated by a broader family of protein acetyltransferases. The recent structure determination of several protein acetyltransferases has provided a wealth of molecular information regarding structural features of protein acetyltransferases, their enzymatic mechanisms, their mode of substrate‐specific recognition and their regulatory elements. In this review, we briefly describe what is known about non‐histone protein substrates, but mainly focus on a few recent structures of protein acetyltransferases to compare and contrast them with histone acetyltransferases to better understand the molecular basis for protein recognition and modification by this family of protein modification enzymes.