Shear-dependent platelet aggregation size

Nonsurgical bleeding is the most frequent complication of left ventricular assist device (LVAD) support. Supraphysiologic shear rates generated in LVAD causes impaired platelet aggregation, which increases the risk of bleeding. The effect of shear rate on the formation size of platelet aggregates has never been reported experimentally, although platelet aggregation size can be considered to be directly relevant to bleeding complications. Therefore, this study investigated the impact of shear rate and exposure time on the formation size of platelet aggregates, which is vital in predicting bleeding in patients with an LVAD. Human platelet-poor plasma (containing von Willebrand factor, vWF) and fluorochrome-labeled platelets were subjected to a range of shear rates (0-10 000 s⁻¹) for 0, 5, 10, and 15 minutes using a custom-built blood-shearing device. Formed sizes of platelet aggregates under a range of shear-controlled environment were visualized and measured using microscopy. The loss of high molecular weight (HMW) vWF multimers was quantified using gel electrophoresis and immunoblotting. An inhibition study was also performed to investigate the reduction in platelet aggregation size and HMW vWF multimers caused by either mechanical shear or enzymatic (a disintegrin and metalloproteinase with a thrombospondin type 1 motif, member 13—ADAMTS13, the von Willebrand factor protease) mechanism under low and high shear conditions (360 and 10 000 s⁻¹). We found that the average size of platelet aggregates formed under physiological shear rates of 360-3000 s⁻¹ (200-300 μm²) was significantly larger compared to those sheared at >6000 s⁻¹ (50-100 μm²). Furthermore, HMW vWF multimers were reduced with increased shear rates. The inhibition study revealed that the reduction in platelet aggregation size and HWM vWF multimers were mainly associated with ADAMTS13. In conclusion, the threshold of shear rate must not exceed >6000 s⁻¹ in order to maintain the optimal size of platelet aggregates to “plug off” the injury site and stop bleeding.     

Exploring the motives of Israeli Jews who were living kidney donors to strangers

Non-directed living donors are individuals who donate a kidney to a recipient with whom they have neither a genetic nor emotional relationship. Israel legalized this type of donation in 2008. After this law was implemented, living donations significantly expanded. The aim of this article was to determine the motivations, characteristics, and perioperative experiences of non-directed living donors in Israel. Three online questionnaires (own questionnaire, Rosenberg Self-Esteem Scale (RSES), Rushton Self-Report Altruism Scale) were distributed to 180 Jewish kidney donors with the help of Matnat Chaim organization. One hundred and fifteen responses were received (69.3% response rate). The motivation for most donors (60%) was a strong willingness to help and a desire to do good. The majority of donors (78.3%) reported their health status as unchanged after donation; however, 16.5% experienced clinical problems (eg, wound infection, more pain than expected), and 5.2% experienced psychological complications. About 18% reported their health to improve after donation. Most (80%) inspired someone else to also become a kidney donor. This study breaks the myth that Jews do not support organ donation. In fact, their high level of altruism and their positive experience with donation has propelled the practice of non-directed donation in Israel.     

In-House Pureed Food Production in Long-Term Care: Perspectives of Dietary Staff and Implications for Improvement

Texture modification of foods to a pureed consistency is a common management approach for older adults with dysphagia. Long-term care (LTC) facilities commonly produce some pureed food in-house. This study investigated challenges and preferred practices associated with the production of pureed food in LTC facilities. Nutrition Managers (n = 27) and cooks (n = 26) from 25 Ontario LTC facilities were recruited for one-on-one, semistructured interviews. Interviews were digitally recorded, transcribed, and analyzed using inductive thematic analysis. Four themes arose from the data to exemplify challenges in production, including (a) difficulty in using standardized recipes, (b) varied interpretation of governmental guidelines, (c) lack of consistency in terminology and texture, and (d) wanting to improve the visual appeal. These challenges were reported to reduce the quality of in-house produced pureed food. Preferred practices to overcome these challenges were also provided by participants, such as involving cooks in pureed recipe improvements and tailoring to the specific needs of residents. Incorporation of these practices into pureed food production may help to shape and improve future practice and pureed food products.     

Reaching a shared understanding of shared decision making in health care: NICE's experience of scoping the shared decision making guideline

NICE's guideline on shared decision making, currently under development, endeavours to support shared decision making as part of routine health care practice. In this article, we summarize our learning to date, gained through the scoping of the guideline, on the key challenges that need to be addressed in the guideline. The production of a scope is the first stage in the development of a NICE guideline, setting the parameters for what will be considered in the guideline. The process for scoping the shared decision making guideline involved discussion with early recruited committee members and engagement with registered stakeholders, through both a workshop and formal consultation. Important, and sometimes divergent, viewpoints about shared decision making were revealed through this process. The key challenges centred on the issues of a need for a common definition of shared decision making, measurability, opportunities, barriers to implementation, and feasibility. Recognizing these challenges aided the refinement of the scope in terms of what the guideline will cover, draft questions and main outcomes for consideration.     

Oncogene cooperation in tumor maintenance and tumor recurrence in mouse mammary tumors induced by Myc and mutant Kras

Most, if not all, cancers are composed of cells in which more than one gene has a cancer-promoting mutation. Although recent evidence has shown the benefits of therapies targeting a single mutant protein, little attention has been given to situations in which experimental tumors are induced by multiple cooperating oncogenes. Using combinations of doxycycline-inducible and constitutive Myc and mutant Kras transgenes expressed in mouse mammary glands, we show that tumors induced by the cooperative actions of two oncogenes remain dependent on the activity of a single oncogene. Deinduction of either oncogene individually, or both oncogenes simultaneously, led to partial or complete tumor regression. Prolonged remission followed deinduction of Kras(G12D) in the context of continued Myc expression, deinduction of a MYC transgene with continued expression of mutant Kras produced modest effects on life extension, whereas simultaneous deinduction of both MYC and Kras(G12D) transgenes further improved survival. Disease relapse after deinduction of both oncogenes was associated with reactivation of both oncogenic transgenes in all recurrent tumors, often in conjunction with secondary somatic mutations in the tetracycline transactivator transgene, MMTV-rtTA, rendering gene expression doxycycline-independent. These results demonstrate that tumor viability is maintained by each gene in a combination of oncogenes and that targeted approaches will also benefit from combination therapies.     

A Retrospective lyrical analysis of songs written by adolescents with anorexia nervosa

Song‐writing plays a central role in music therapy with adolescents. A retrospective lyrical analysis of songs written by adolescents with anorexia nervosa was undertaken in order to identify common themes solicited through song‐writing interventions. Fifteen participants contributed 17 songs, from which 368 lyrical units were identified. A modified content analysis approach was used with each lyrical unit being categorised to one of six themes determined from the literature and clinical experience. The theme of ‘identity’ was used most frequently (28%), with the sub‐theme of ‘exploring new behaviours, positive self‐talk’ being addressed most often (12.5% of total). The dominance of the developmentally important theme of ‘identity’ may reflect the relationship between adolescents, music and identity or may be related to the way in which anorexia nervosa has been theorised to assist the adolescent in managing challenges to the emerging sense of self. Copyright © 2006 John Wiley & Sons, Ltd and Eating Disorders Association.