Type A Dissection Presenting as a Double Aortic Valve

We report a case of spontaneous aortic root dissection in a middle-aged male without history of recent trauma, mimicking double aortic valve on the echocardiogram which extended to the right brachiocephalic artery. The patient immediately underwent Bentall procedure

An integrated and coordinated approach to preventing recurrent coronary heart disease events in Australia: Policy statement from the Australian Cardiovascular Health and Rehabilitation Association

• Implementing existing knowledge about cardiac rehabilitation (CR) and heart failure management could markedly reduce mortality after acute coronary syndromes and revascularisation therapy. • Contemporary CR and secondary prevention programs are cost-effective, safe and beneficial for patients of all ages, leading to improved survival, fewer revascularisation procedures and reduced rehospitalisation. • Despite the proven benefits attributed to these secondary prevention interventions, they are not well attended by patients. • Modern programs must be flexible, culturally safe, multifaceted and integrated with the patient's primary health care provider to achieve optimal and sustainable benefits for most patients

Differences between patients with ventricular tachycardia and ventricular fibrillation as assessed by signal-averaged electrocardiogram, radionuclide ventriculography and cardiac mapping

AbstractThis study examined 65 patients with ventricular tachycardia or fibrillation late after myocardial infarction to determine whether they differed with respect to duration of ventricular activation in sinus rhythm and left ventricular ejection fraction. Patients with spontaneous ventricular tachycardia had a longer ventricular activation time in sinus rhythm than did patients with spontaneous ventricular fibrillation. This difference was detected with the signal-averaged electrocardiogram (ECG) (tachycardia 181 ± 33 ms, fibrillation 152 ± 23 ms, p < 0.001) and at epicardial mapping (tachycardia 210 ± 17 ms, fibrillation 192 ± 17 ms, p < 0.02). Left ventricular ejection fraction was lower in patients with spontaneous ventricular tachycardia (0.22 ± 0.09) than in patients with spontaneous ventricular fibrillation (0.27 ± 0.09) (p < 0.05).The patients with both spontaneous and inducible ventricular fibrillation had a shorter ventricular activation time on the signal-averaged ECG (129 ± 17 ms) and a higher ejection fraction (0.36 ± 0.05) than did either patients with spontaneous ventricular fibrillation and inducible ventricular tachycardia (158 ± 21 ms and 0.25 ± 0.08, respectively, each p < 0.01) or patients with both spontaneous and inducible ventricular tachycardia (181 ± 33 ms and 0.22 ± 0.09, respectively, each p < 0.001). Of the patients with inducible ventricular tachycardia, presentation with tachycardia rather than fibrillation was associated with a longer ventricular activation time on the signal-averaged ECG (181 ± 33 versus 158 ± 21 ms, p < 0.02) and a longer cycle length of inducible ventricular tachycardia (290 ± 61 versus 259 ± 44 ms, p = 0.05).In conclusion, conduction delay during sinus rhythm and left ventricular dysfunction appear to be greatest in patients with spontaneous and inducible ventricular tachycardia, and least in patients with spontaneous and inducible ventricular fibrillation

Toward Engineering Biosystems With Emergent Collective Functions

Many complex behaviors in biological systems emerge from large populations of interacting molecules or cells, generating functions that go beyond the capabilities of the individual parts. Such collective phenomena are of great interest to bioengineers due to their robustness and scalability. However, engineering emergent collective functions is difficult because they arise as a consequence of complex multi-level feedback, which often spans many length-scales. Here, we present a perspective on how some of these challenges could be overcome by using multi-agent modeling as a design framework within synthetic biology. Using case studies covering the construction of synthetic ecologies to biological computation and synthetic cellularity, we show how multi-agent modeling can capture the core features of complex multi-scale systems and provide novel insights into the underlying mechanisms which guide emergent functionalities across scales. The ability to unravel design rules underpinning these behaviors offers a means to take synthetic biology beyond single molecules or cells and toward the creation of systems with functions that can only emerge from collectives at multiple scales

Toward engineering biosystems with emergent collective functions

Many complex behaviors in biological systems emerge from large populations of interacting molecules or cells, generating functions that go beyond the capabilities of the individual parts. Such collective phenomena are of great interest to bioengineers due to their robustness and scalability. However, engineering emergent collective functions is difficult because they arise as a consequence of complex multi-level feedback, which often spans many length-scales. Here, we present a perspective on how some of these challenges could be overcome by using multi-agent modeling as a design framework within synthetic biology. Using case studies covering the construction of synthetic ecologies to biological computation and synthetic cellularity, we show how multi-agent modeling can capture the core features of complex multi-scale systems and provide novel insights into the underlying mechanisms which guide emergent functionalities across scales. The ability to unravel design rules underpinning these behaviors offers a means to take synthetic biology beyond single molecules or cells and toward the creation of systems with functions that can only emerge from collectives at multiple scales

Depression at Work, Authenticity in Question: Experiencing, Concealing and Revealing

Australia and the UK have both introduced policies to protect employees who experience mental illness, including depression. However, a better understanding of the issues workers face (e.g. sense of moral failure) is needed for the provision of appropriate and beneficial support. We analysed 73 interviews from the UK and Australia where narratives of depression and work intersected. Participants encountered difficulties in being (and performing as if) ‘authentic’ at work, with depression contributing to confusions about the self. The diffuse post-1960s imperative to ‘be yourself’ is experienced in conflicting ways: While some participants sought support from managers and colleagues (e.g. sick leave, back to work plans), many others put on a façade in an attempt to perform the ‘well’ and ‘authentic’ employee. We outline the contradictory forces at play for participants when authenticity and visibility are expected, yet moral imperatives to be good (healthy) employees are normative

Post-depositional fracturing and subsidence of pumice flow deposits: Lascar Volcano, Chile

Unconsolidated pyroclastic flow deposits of the 1993 eruption of Lascar Volcano, Chile, have, with time, become increasingly dissected by a network of deeply penetrating fractures. The fracture network comprises orthogonal sets of decimeter-wide linear voids that form a pseudo-polygonal grid visible on the deposit surface. In this work, we combine shallow surface geophysical imaging tools with remote sensing observations and direct field measurements of the deposit to investigate these fractures and their underlying causal mechanisms. Based on ground penetrating radar images, the fractures are observed to have propagated to depths of up to 10 m. In addition, orbiting radar interferometry shows that deposit subsidence of up to 1 cm/year occurred between 1993 and 1996 with continued subsidence occurring at a slower rate thereafter. In situ measurements show that 1 m below the surface, the 1993 deposits remain 5°C to 15°C hotter, 18 years after emplacement, than adjacent deposits. Based on the observed subsidence as well as estimated cooling rates, the fractures are inferred to be the combined result of deaeration, thermal contraction, and sedimentary compaction in the months to years following deposition. Significant environmental factors, including regional earthquakes in 1995 and 2007, accelerated settling at punctuated moments in time. The spatially variable fracture pattern relates to surface slope and lithofacies variations as well as substrate lithology. Similar fractures have been reported in other ignimbrites but are generally exposed only in cross section and are often attributed to formation by external forces. Here we suggest that such interpretations should be invoked with caution, and deformation including post-emplacement subsidence and fracturing of loosely packed ash-rich deposits in the months to years postemplacement is a process inherent in the settling of pyroclastic material

Effects of antiplatelet therapy on stroke risk by brain imaging features of intracerebral haemorrhage and cerebral small vessel diseases: subgroup analyses of the RESTART randomised, open-label trial

Background Findings from the RESTART trial suggest that starting antiplatelet therapy might reduce the risk of recurrent symptomatic intracerebral haemorrhage compared with avoiding antiplatelet therapy. Brain imaging features of intracerebral haemorrhage and cerebral small vessel diseases (such as cerebral microbleeds) are associated with greater risks of recurrent intracerebral haemorrhage. We did subgroup analyses of the RESTART trial to explore whether these brain imaging features modify the effects of antiplatelet therapy

An intervention to promote physical activity and self-management in people with stable chronic heart failure The Home-Heart-Walk study: study protocol for a randomized controlled trial

<p>Abstract</p> <p>Background</p> <p>Chronic heart failure (CHF) is a chronic debilitating condition with economic consequences, mostly because of frequent hospitalisations. Physical activity and adequate self-management capacity are important risk reduction strategies in the management of CHF. The Home-Heart-Walk is a self-monitoring intervention. This model of intervention has adapted the 6-minute walk test as a home-based activity that is self-administered and can be used for monitoring physical functional capacity in people with CHF. The aim of the Home-Heart-Walk program is to promote adherence to physical activity recommendations and improving self-management in people with CHF.</p> <p>Methods/Design</p> <p>A randomised controlled trial is being conducted in English speaking people with CHF in four hospitals in Sydney, Australia. Individuals diagnosed with CHF, in New York Heart Association Functional Class II or III, with a previous admission to hospital for CHF are eligible to participate. Based on a previous CHF study and a loss to follow-up of 10%, 166 participants are required to be able to detect a 12-point difference in the study primary endpoint (SF-36 physical function domain).</p> <p>All enrolled participant receive an information session with a cardiovascular nurse. This information session covers key self-management components of CHF: daily weight; diet (salt reduction); medication adherence; and physical activity. Participants are randomised to either intervention or control group through the study randomisation centre after baseline questionnaires and assessment are completed. For people in the intervention group, the research nurse also explains the weekly Home-Heart-Walk protocol. All participants receive monthly phone calls from a research coordinator for six months, and outcome measures are conducted at one, three and six months. The primary outcome of the trial is the physical functioning domain of quality of life, measured by the physical functioning subscale of the Medical Outcome Study Short Form -36. Secondary outcomes include physical functional capacity measured by the standard six minute walk test, self-management capacity, health related quality of life measured by Medical Outcome Study Short Form -36 and Minnesota Living With Heart Failure Questionnaire, self-efficacy and self-care behaviour.</p> <p>Discussion</p> <p>A self-monitoring intervention that can improve individual's exercise self-efficacy, self-management capacity could have potential significance in improving the management of people with chronic heart failure in community settings.</p> <p>Trial Registration</p> <p>Australian New Zealand Clinical Trial Registry 12609000437268</p