Unintended cardiac irradiation during left-sided breast cancer radiotherapy

Objective: Cardiac irradiation during left-sided breast radiotherapy may lead to
deleterious cardiac side effects. Using image guided radiotherapy, it is possible
to exclude the heart from treatment fields and monitor reproducibility of virtual simulation (VS) fields at treatment delivery using electronic portal imaging (EPI). Retrospectively, we evaluate the incidence of cardiac irradiation at VS and subsequent unintended cardiac irradiation during treatment.

Methods: Patients receiving left-sided radiotherapy to the breast or chest wall,
treated with a glancing photon field technique during a four-month period, were
included. VS images and EPIs during radiotherapy delivery were visually assessed.
The presence of any portion of the heart within the treatment field at VS or during treatment was recorded. Central lung distance and maximum heart distance were recorded.

Results: Of 128 patients, 45 (35.1%) had any portion of the heart within the
planned treatment field. Of these, inclusion of the heart was clinically unavoidable in 25 (55.6%). Of those with no heart included in the treatment fields at VS, 41 (49.4%) had presence of the heart as assessed on EPI during treatment.

Conclusion: Unintended cardiac irradiation during left-sided breast radiotherapy treatment occurs in a sizeable proportion of patients.

Advances in knowledge: Despite the use of three-dimensional computed tomography simulation and cardiac shielding, sizeable proportions of patients receiving left-sided breast cancer radiotherapy have unintended cardiac irradiation.

Where would you turn for help?:Older adults' awareness of community support services

Previous findings on older adults' awareness of community support services (CSSs) have been inconsistent and marred by acquiescence or over-claiming bias. To address this issue, this study used a series of 12 vignettes to describe common situations faced by older adults for which CSSs might be appropriate. In telephone interviews, 1,152 adults aged 50 years and over were read a series of vignettes and asked if they were able to identify a community organization or agency that they may turn to in that situation. They were also asked about their most important sources of information about CSSs. The findings show that, using a vignette methodology, awareness of CSSs is much lower than previously thought. The most important sources of information about CSSs included information and referral sources, the telephone book, doctors' offices, and word of mouth.

Would older adults turn to community support services for help to maintain their independence?

The purpose of this article is to determine whether middle-aged and older adults would identify community support services (CSSs) as a source of assistance for difficulties with the instrumental activities of daily living (IADLs). Furthermore, we determine factors related to the identification of home health and CSSs. Telephone interviews were conducted with 768 adults aged 50 and older. Respondents were presented with a vignette describing a situation where loss of independence is threatened. They were asked what they would do in that situation. Although less than 20% mentioned CSSs, nearly 50% mentioned either a home health or CSS. Findings suggest those less likely to mention a home health or CSS include men, older adults, and the foreign born. In addition, those with less education, functional health limitations, no social support, and a lack of knowledge of where to find information about CSSs mentioned home health or CSSs less often. © The Author(s) 2010.

When care is left to roam: Carers' experiences of grassroots nonprofit services in Ireland

Increasingly countries are turning to nonprofit organisations to provide health and social care, particularly for people with disabilities. Alongside this change, debates continue about how states should manage the relationship with such organisations. Should features of the old-style "welfare" model be retained? Should aspects of the "new public management" model be chosen to measure the impact of the work? Yet others argue that grassroots organisations should form the basis of a service provision system. In the context of these debates, Ireland serves as an interesting case study of the system of care that can emerge when the state operates a "relaxed control" approach. This paper takes the perspectives of users themselves: family carers who are accessing services for a disabled adult child, to examine the effects of this approach on the ground. We show how geography played a central role in shaping these experiences, and discuss how we can learn from the Irish context. Rather than arguing for narrowly defined contractual measures, we conclude by proposing a renewed focus on relationship building with the aim of effective system operation, in the future of care services. © 2010 Elsevier Ltd.

Distinctive Profile of IsomiR Expression and Novel MicroRNAs in Rat Heart Left Ventricle

MicroRNAs (miRNAs) are single-stranded non-coding RNAs that negatively regulate target gene expression through mRNA cleavage or translational repression. There is mounting evidence that they play critical roles in heart disease. The expression of known miRNAs in the heart has been studied at length by microarray and quantitative PCR but it is becoming evident that microRNA isoforms (isomiRs) are potentially physiologically important. It is well known that left ventricular (patho)physiology is influenced by transmural heterogeneity of cardiomyocyte phenotype, and this likely reflects underlying heterogeneity of gene expression. Given the significant role of miRNAs in regulating gene expression, knowledge of how the miRNA profile varies across the ventricular wall will be crucial to better understand the mechanisms governing transmural physiological heterogeneity. To determinine miRNA/isomiR expression profiles in the rat heart we investigated tissue from different locations across the left ventricular wall using deep sequencing. We detected significant quantities of 145 known rat miRNAs and 68 potential novel orthologs of known miRNAs, in mature, mature* and isomiR formation. Many isomiRs were detected at a higher frequency than their canonical sequence in miRBase and have different predicted targets. The most common miR-133a isomiR was more effective at targeting a construct containing a sequence from the gelsolin gene than was canonical miR-133a, as determined by dual-fluorescence assay. We identified a novel rat miR-1 homolog from a second miR-1 gene; and a novel rat miRNA similar to miR-676. We also cloned and sequenced the rat miR-486 gene which is not in miRBase (v18). Signalling pathways predicted to be targeted by the most highly detected miRNAs include Ubiquitin-mediated Proteolysis, Mitogen-Activated Protein Kinase, Regulation of Actin Cytoskeleton, Wnt signalling, Calcium Signalling, Gap junctions and Arrhythmogenic Right Ventricular Cardiomyopathy. Most miRNAs are not expressed in a gradient across the ventricular wall, with exceptions including miR-10b, miR-21, miR-99b and miR-486.

Cheetahs, Acinonyx jubatus, balance turn capacity with pace when chasing prey

Predator–prey interactions are fundamental in the evolution and structure of ecological communities. Our understanding, however, of the strategies used in pursuit and evasion remains limited. Here, we report on the hunting dynamics of the world's fastest land animal, the cheetah, Acinonyx jubatus. Using miniaturized data loggers, we recorded fine-scale movement, speed and acceleration of free-ranging cheetahs to measure how hunting dynamics relate to chasing different sized prey. Cheetahs attained hunting speeds of up to 18.94 m s-1 and accelerated up to 7.5 m s-2 with greatest angular velocities achieved during the terminal phase of the hunt. The interplay between forward and lateral acceleration during chases showed that the total forces involved in speed changes and turning were approximately constant over time but varied with prey type. Thus, rather than a simple maximum speed chase, cheetahs first accelerate to decrease the distance to their prey, before reducing speed 5–8 s from the end of the hunt, so as to facilitate rapid turns to match prey escape tactics, varying the precise strategy according to prey species. Predator and prey thus pit a fine balance of speed against manoeuvring capability in a race for survival.