Precision proteoform design for 4R tau isoform selective templated aggregation.

Prion-like spread of disease-specific tau conformers is a hallmark of all tauopathies. A 19-residue probe peptide containing a P301L mutation and spanning the R2/R3 splice junction of tau folds and stacks into seeding-competent fibrils and induces aggregation of 4R, but not 3R tau. These tau peptide fibrils propagate aggregated intracellular tau over multiple generations, have a high ß-sheet content, a colocalized lipid signal, and adopt a well-defined U-shaped fold found in 4R tauopathy brain-derived fibrils. Fully atomistic replica exchange molecular dynamics (MD) simulations were used to compute the free energy landscapes of the conformational ensemble of the peptide monomers. These identified an aggregation-prohibiting ß-hairpin structure and an aggregation-competent U-fold unique to 4R tauopathy fibrils. Guided by MD simulations, we identified that the N-terminal-flanking residues to PHF6, which slightly vary between 4R and 3R isoforms, modulate seeding. Strikingly, when a single amino acid switch at position 305 replaced the serine of 4R tau with a lysine from the corresponding position in the first repeat of 3R tau, the seeding induced by the 19-residue peptide was markedly reduced. Conversely, a 4R tau mimic with three repeats, prepared by replacing those amino acids in the first repeat with those amino acids uniquely present in the second repeat, recovered aggregation when exposed to the 19-residue peptide. These peptide fibrils function as partial prions to recruit naive 4R tau-ten times the length of the peptide-and serve as a critical template for 4R tauopathy propagation. These results hint at opportunities for tau isoform-specific therapeutic interventions.

What do I eat? Impact of an interactive teaching method for improving pharmacy students' diabetes nutrition knowledge and comfort in providing nutrition counseling.

BACKGROUND AND PURPOSE: Didactic approaches for instructing students about diabetes nutrition and self-management have been described previously in the pharmacy education literature. There is a need for diabetes nutrition active learning approaches that can be incorporated into the advanced pharmacy practice experience (APPE) setting so students can apply previous didactic learning in a real world setting. The goal was to add to students' knowledge of diabetes nutrition thereby increasing their comfort in discussing nutrition with patients. EDUCATIONAL ACTIVITY AND SETTING: The nutrition tour activity was implemented in the APPE setting and involved pharmacy students on ambulatory and inpatient rotations. The nutrition tour included several active learning exercises such as evaluation of nutrition labels and development of a day-long carbohydrate-consistent meal plan to encourage student engagement and application of information. Student pre- and post-activity survey data was collected two weeks before and two weeks after the tour to assess retention of knowledge of diabetes nutrition and comfort in diabetes nutrition education. Changes in knowledge and comfort were assessed using t-tests. FINDINGS: Fifty-five pharmacy students participated in the nutrition tour with 45 completing the pre-activity survey and 40 completing the post-activity survey. Comparison of student pre- and post-activity survey scores identified statistically significant increases in both total nutrition knowledge (p < 0.001) and student comfort in counseling on diabetes nutrition (p < 0.001). DISCUSSION AND SUMMARY: A diabetes nutrition tour guided by a pharmacy preceptor for APPE students was associated with increased diabetes nutrition knowledge and comfort in educating on diabetes nutrition.

"Pimping" in Pharmacy Education: A Survey and Comparison of Student and Faculty Views.

BACKGROUND: "Pimping" is an informal teaching technique that is widely used in medical education. Pimping is characterized by questioning the learner with the intent of reinforcing clinical hierarchy. To date, there are no studies of the use of pimping in pharmacy education. OBJECTIVES: To describe the use of pimping as a teaching method in pharmacy education and to compare student and faculty perceptions of this technique. METHODS: Faculty and fourth-year PharmD (P4) students from 2 colleges of pharmacy were invited to participate in a survey about experiences and perceptions of pimping. Faculty and P4 surveys each contained up to 17 items to assess personal experiences, utilization, perceived risks and benefits, and preferences regarding the role of the technique in pharmacy education. RESULTS: The response rate was 49.5% (159 of 321). Of faculty, 74.1% reported they had been pimped in their training, but less than half (45.8%) use pimping themselves. Similarly, 73.7% of students reported that they had been pimped at some time in their pharmacy education. Students nearly equally viewed their experiences as positive (35.3%) versus negative (38.2%). Responses were similar between faculty and students recommending that the method should be avoided entirely ( P = .259), used sparingly ( P = .072), or used consistently ( P = .309). Perceived benefits and risks of pimping were similar between faculty and students, but there were many differences in rationales offered by faculty versus students' perceived rationales. CONCLUSION: Pimping is common in pharmacy education and its use is controversial. The perceived rationale for use of pimping differs, which may undermine student/faculty relationships.

Assessment of the acquisition of executive function during the transition from adolescence to adulthood in male and female mice.

Executive functions (EF) reached full maturity during the transition from adolescence to adulthood. Human studies provide important information about adolescent developmental trajectories; however, little remains known about the neural circuits underlying the acquisition of mature EF. Ethical and technical considerations with human subjects limit opportunities to design experimental studies that allows for an in-depth understanding of developmental changes in neural circuits that regulate cognitive maturation. Preclinical models can offer solutions to this problem. Unfortunately, current rodent models of adolescent development have inherent flaws that limit their translational value. For instance, females are often omitted from studies, preventing the assessment of potential sex-specific developmental trajectories. Furthermore, it remains unclear whether cognitive developmental changes in rodents are similar to those observed in humans. Here, we tested adolescent and adult male and female mice in a neurocognitive battery of assays. Based on this approach, we assessed mice performances within distinct subdomains of EF, and observed similarities with human developmental trajectories. Furthermore, the sex-specific cognitive changes we observed were paralleled by molecular and neural activity changes demonstrating that our approach can be used in future research to assess the contribution of precise neural circuits to adolescent cognitive maturation.

The 5.5 protein of phage T7 inhibits H-NS through interactions with the central oligomerization domain.

The 5.5 protein (T7p32) of coliphage T7 (5.5(T7)) was shown to bind and inhibit gene silencing by the nucleoid-associated protein H-NS, but the mechanism by which it acts was not understood. The 5.5(T7) protein is insoluble when expressed in Escherichia coli, but we find that 5.5(T7) can be isolated in a soluble form when coexpressed with a truncated version of H-NS followed by subsequent disruption of the complex during anion-exchange chromatography. Association studies reveal that 5.5(T7) binds a region of H-NS (residues 60 to 80) recently found to contain a distinct domain necessary for higher-order H-NS oligomerization. Accordingly, we find that purified 5.5(T7) can disrupt higher-order H-NS-DNA complexes in vitro but does not abolish DNA binding by H-NS per se. Homologues of the 5.5(T7) protein are found exclusively among members of the Autographivirinae that infect enteric bacteria, and despite fairly low sequence conservation, the H-NS binding properties of these proteins are largely conserved. Unexpectedly, we find that the 5.5(T7) protein copurifies with heterogeneous low-molecular-weight RNA, likely tRNA, through several chromatography steps and that this interaction does not require the DNA binding domain of H-NS. The 5.5 proteins utilize a previously undescribed mechanism of H-NS antagonism that further highlights the critical importance that higher-order oligomerization plays in H-NS-mediated gene repression.

Transcriptional repression of SKP2 is impaired in MYCN-amplified neuroblastoma.

The cell cycle regulator, SKP2, is overexpressed in various cancers and plays a key role in p27 degradation, which is involved in tumor cell dedifferentiation. Little is known about the mechanisms leading to impaired SKP2 transcriptional control in tumor cells. We used neuroblastoma as a model to study SKP2 regulation because SKP2 transcript levels gradually increase with aggressiveness of neuroblastoma subtypes. The highest SKP2 levels are found in neuroblastomas with amplified MYCN. Accordingly, we found 5.5-fold (range, 2-9.5) higher SKP2 core promoter activity in MYCN-amplified cells. Higher SKP2 core promoter activity in MYCN-amplified cells is mediated through a defined region at the transcriptional start site. This region includes a specific E2F-binding site that makes SKP2 activation largely independent of mitogenic signals integrated through the SP1/ELK-1 site. We show by chromatin immunoprecipitation that SKP2 activation through the transcriptional start site in MYCN-amplified cells is associated with the low abundance of pRB-E2F1 complexes bound to the SKP2 promoter. Transcriptional control of SKP2 through this regulatory mechanism can be reestablished in MYCN-amplified cells by restoring pRB activity using selective small compound inhibitors of CDK4. In contrast, doxorubicin or nutlin-3 treatment-both leading to p53-p21 activation-or CDK2 inhibition had no effect on SKP2 regulation in MYCN-amplified cells. Together, this implies that deregulated MYCN protein levels in MYCN-amplified neuroblastoma cells activate SKP2 through CDK4 induction, abrogating repressive pRB-E2F1 complexes bound to the SKP2 promoter.

Utilization of psychiatric services integrated with primary care by persons of color with HIV in the inner city.

We identify the psychiatric diagnoses and utilization patterns of HIV-positive persons of color who received culturally responsive mental health services integrated into a community medical clinic. Ninety-three patients were referred and 86% (n = 80) appeared for at least one encounter. Hispanics, compared with African-Americans, and HIV patients, compared with AIDS patients, were more likely to receive psychotropic prescriptions. Patients with six or more visits were defined as high utilizers: they comprised 27.5% of the patients but used 67.3% of the services. Development of a broader range of psychiatric interventions that address diagnoses, utilization, and psychotropics will better meet these patients' needs.