Fluorescence resonance energy transfer (FRET) provides a powerful means to study protein conformational changes. However, the incorporation of an exogenous FRET pair into a protein could lead to undesirable structural perturbations of the native fold. One of the viable strategies to minimizing such perturbations is to use non-natural amino acid based FRET pairs. Previously we have shown that p-cyanophenylalanine (Phe CN ) and tryptophan (Trp) constitute such a FRET pair, useful for monitoring protein folding-unfolding transitions. Herein, we further show that 7-azatryptophan (7AW) and 5-hydroxytryptophan (5HW) can also serve as a FRET acceptor to Phe CN , and the resultant FRET pairs offer certain advantages over Phe CN -Trp. For example, the fluorescence spectrum of 7AW is sufficiently separated from that of Phe CN , making it straightforward to decompose the FRET spectrum into donor and acceptor contributions. Moreover, we show that Phe CN , Trp and 7AW can be used together to form a multi-FRET system, allowing more structural information to be extracted from a single FRET experiment. The applicability of these FRET systems is demonstrated in a series of studies wherein they are employed to monitor the urea-induced unfolding transitions of the villin headpiece subdomain (HP35), a designed ββα motif (BBA5), and the human Pin1 WW domain.

The structure and function of the Influenza A M2 proton channel have been the subject of intensive investigations in recent years because of its critical role in the life cycle of the Influenza virus. Using a truncated version of the M2 proton channel (i.e., M2TM) as a model, here we show that fluctuations in the fluorescence intensity of a dye reporter that arise from both fluorescence quenching via the mechanism of photoinduced electron transfer (PET) by an adjacent tryptophan (Trp) residue and local motions of the dye molecule can be used to probe the conformational dynamics of membrane proteins. Specifically, we find that the dynamics of the conformational transition between the N-terminally-open and C-terminally-open states of the M2TM channel occur on a timescale of about 500 μs and that binding of either amantadine or rimantadine does not inhibit the pH-induced structural equilibrium of the channel. These results are consistent with the direct occluding mechanism of inhibition which suggests that the antiviral drugs act by sterically occluding the channel pore.

Intergenerational programs are an authentic way to engage elders in meaningful activity and report benefits to both elders and youth. The Avondale Intergenerational Design Challenge (AVID) randomly assigned small teams of technology students aged 13 to 15 years (total N = 59) to 1 of 24 aged care residents with a range of cognitive impairment. Students met with the resident 4 times over 15 weeks and ultimately crafted a personalized item for them. Students showed no change in self-reported attitudes to elders, empathy, or self-esteem post-AVID or at 3-month follow-up, compared to a 3-month within-subject control period pre-AVID. Compared to usual lifestyle activities, residents showed significant improvements in self-reported positive affect and negative affect after student visits and were observed to be significantly more engaged during visits, especially residents with greater cognitive impairment. The personal and guided nature of intergenerational programs may be especially effective in engaging elders with cognitive impairment in meaningful activity.

Introduction Millions of American patients have a disability, and their health care outcomes depend on the attitudes of their health care providers towards persons with disabilities. Overly negative health care provider attitudes lead to significant misunderstandings about what it means to have a disability, inappropriate assumptions, and poor care. However, very few medical schools teach about disability. Methods We developed a preclinical medical student curriculum that addresses the complexity of disability, focusing on health care disparities and bias. Our curriculum was designed with significant input from people with disabilities and was constructed from their perspective. In addition to didactic and discussion sessions on disability history, models of disability, and health disparities, we include a discussion panel with community members who have a disability. Results The curriculum has been effective at promoting discussion and is well received by students. When rating the relevance to future clinical practice, students gave the curriculum an average of 3.9 on a 5-point Likert scale (1 = poor , 5 = excellent ). The majority of students commented that the community involvement in the session was the most meaningful aspect. Discussion It is possible to integrate community-driven discussions on the social context of disability into traditional medical school preclinical curricula, and students find it valuable to their education.

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