Impact of sample history and solvent effects on pathway control in the supramolecular polymerisation of Au(i)-metallopeptide amphiphiles.

We investigate the kinetics of the supramolecular polymerisation of an Au(i)-metallopeptide amphiphile that assembles into exceptionally long and rigid nanofibers. We developed a precise preparation protocol to measure the concentration dependent assembly kinetics which elucidated a nucleation-elongation dominated supramolecular polymerisation process. We show striking differences in the assembly behavior and morphology in aqueous media, even at organic solvent contents as low as 1 vol%, compared to pure buffer.

Values and preferences for oral antithrombotic therapy in patients with atrial fibrillation: physician and patient perspectives.

BACKGROUND: Exploration of values and preferences in the context of anticoagulation therapy for atrial fibrillation (AF) remains limited. To better characterize the distribution of patient and physician values and preferences relevant to decisions regarding anticoagulation in patients with AF, we conducted interviews with patients at risk of developing AF and physicians who manage patients with AF. METHODS: We interviewed 96 outpatients and 96 physicians in a multicenter study and elicited the maximal increased risk of bleeding (threshold risk) that respondents would tolerate with warfarin vs. aspirin to achieve a reduction in three strokes in 100 patients over a 2-year period. We used the probabilistic version of the threshold technique. RESULTS: The median threshold risk for both patients and physicians was 10 additional bleeds (10 P = 0.7). In both groups, we observed large variability in the threshold number of bleeds, with wider variability in patients than clinicians [patient range: 0-100, physician range: 0-50]. We observed one cluster of patients and physicians who would tolerate <10 bleeds and another cluster of patients, but not physicians, who would accept more than 35. CONCLUSIONS: Our findings suggest wide variability in patient and physician values and preferences regarding the trade-off between strokes and bleeds. Results suggest that in individual decision making, physician and patient values and preferences will often be discordant; this mandates tailoring treatment to the individual patient's preferences.

Values and preferences in oral anticoagulation in patients with atrial fibrillation, physicians' and patients' perspectives: protocol for a two-phase study.

BACKGROUND: Oral anticoagulation prevents strokes in patients with atrial fibrillation but, for reasons that remain unclear, less than 40% of all patients with atrial fibrillation receive warfarin. The literature postulates that patient and clinician preferences may explain this low utilization. DESIGN: The proposed research seeks to answer the following questions: i) When assessed systematically, do patients' and clinicians' preferences explain the utilization of warfarin to prevent strokes associated with atrial fibrillation? ii) To what extent do patients' and clinicians' treatment preferences differ? iii) What factors explain any differences that exist in treatment preferences between patients and clinicians? To answer these questions we will conduct a two-phase study of patient and clinician preferences for health states and treatments. In the first phase of this study we will conduct structured interviews to determine their treatment preferences for warfarin vs. aspirin to prevent strokes associated with atrial fibrillation using the probability trade-off technique. In the same interview, we will conduct preference-elicitation exercises using the feeling thermometer to identify the utilities that patients place on taking medication (warfarin and aspirin), and on having a mild stroke, a severe stroke, and a major bleed. In the second phase of the study we will convene focus groups of clinicians and patients to explore their answers to the exercises in the first phase. DISCUSSION: This is a study of patient and clinician preferences for health states and treatments. Because of its clinical importance and our previous work in this area, we will conduct our study in the clinical context of the decision to use antithrombotic agents to reduce the risk of stroke in patients with non-valvular chronic atrial fibrillation.