Examining the pedagogical practices that support cultural proficiency development in graduate health science students.

BACKGROUND: Health disparities are often a function of systemic discrimination and healthcare providers' biases. In recognition of this, health science programs have begun to offer training to foster cultural proficiency (CP) in future professionals. However, there is not yet consensus about the best ways to integrate CP into didactic and clinical education, and little is known about the role of clinical rotations in fostering CP. METHODS: Here, a mixed-methods approach was used to survey students (n = 131) from a private all-graduate level osteopathic health sciences university to gain insight into the training approaches students encountered related to CP and how these may vary as a function of academic progression. The research survey included instruments designed to quantify students' implicit associations, beliefs, and experiences related to the CP training they encountered through the use of validated instruments, including Implicit Association Tests and the Ethnocultural Empathy Inventory, and custom-designed questions. RESULTS: The data revealed that most students (73%) had received CP training during graduate school which primarily occurred via discussions, lectures, and readings; however, the duration and students' perception of the training varied substantially (e.g., training range = 1-100 hours). In addition, while students largely indicated that they valued CP and sought to provide empathetic care to their patients, they also expressed personal understandings of CP that often fell short of advocacy and addressing personal and societal biases. The results further suggested that clinical rotations may help students attenuate implicit biases but did not appear to be synergistic with pre-clinical courses in fostering other CP knowledge, skills, and attitudes. CONCLUSIONS: These findings highlight the need to utilize evidence-based pedagogical practices to design intentional, integrated, and holistic CP training throughout health science programs that employ an intersectional lens and empowers learners to serve as advocates for their patients and address systemic challenges.

Single Cell RNA-Sequence Analyses Reveal Uniquely Expressed Genes and Heterogeneous Immune Cell Involvement in the Rat Model of Intervertebral Disc Degeneration.

Intervertebral disc (IVD) degeneration is characterized by a loss of cellularity, and changes in cell-mediated activity that drives anatomic changes to IVD structure. In this study, we used single-cell RNA-sequencing analysis of degenerating tissues of the rat IVD following lumbar disc puncture. Two control, uninjured IVDs (L2-3, L3-4) and two degenerated, injured IVDs (L4-5, L5-6) from each animal were examined either at the two- or eight-week post-operative time points. The cells from these IVDs were extracted and transcriptionally profiled at the single-cell resolution. Unsupervised cluster analysis revealed the presence of four known cell types in both non-degenerative and degenerated IVDs based on previously established gene markers: IVD cells, endothelial cells, myeloid cells, and lymphoid cells. As a majority of cells were associated with the IVD cell cluster, sub-clustering was used to further identify the cell populations of the nucleus pulposus, inner and outer annulus fibrosus. The most notable difference between control and degenerated IVDs was the increase of myeloid and lymphoid cells in degenerated samples at two- and eight-weeks post-surgery. Differential gene expression analysis revealed multiple distinct cell types from the myeloid and lymphoid lineages, most notably macrophages and B lymphocytes, and demonstrated a high degree of immune specificity during degeneration. In addition to the heterogenous infiltrating immune cell populations in the degenerating IVD, the increased number of cells in the AF sub-cluster expressing Ngf and Ngfr, encoding for p75NTR, suggest that NGF signaling may be one of the key mediators of the IVD crosstalk between immune and neuronal cell populations. These findings provide the basis for future work to understand the involvement of select subsets of non-resident cells in IVD degeneration.

Creation of a Novel Biomedical Engineering Research Course for Incarcerated Students.

Options for incarcerated individuals to participate in higher education in prison programs (HEPPs) have expanded in recent years to include courses in science, technology, engineering, and mathematics, however these students remain an underserved population in the United States. Thus, there are opportunities to expand the available offerings, increase the diversity of coursework available by introducing subjects such as biomedical engineering (BME), and include cocurricular and extracurricular activities widely considered critical components of undergraduate training including research experiences. As such, a year-long program was developed to introduce students pursuing a bachelor's degree in an HEPP through an R1 institution to research principles in BME. This course introduced students to disciplines within BME, offered opportunities to gain research experience as knowledge-creators, and supported engagement with a scientific learning community. Using a student-centered approach, the course was designed to incorporate activities for reflection, goal setting, and dialogue among participants and sought to leverage students' funds of knowledge and areas of personal scientific interest. This course represents a transferable model for offering BME courses and research-centered opportunities to students enrolled in other HEPPs and an opportunity to promote equity and access in higher education. Supplementary Information: The online version contains supplementary material available at 10.1007/s43683-022-00071-6.

Bioactive in situ crosslinkable polymer-peptide hydrogel for cell delivery to the intervertebral disc in a rat model.

Degeneration of the intervertebral disc (IVD) is associated with significant biochemical and morphological changes that include a loss of disc height, decreased water content and decreased cellularity. Cell delivery has been widely explored as a strategy to supplement the nucleus pulposus (NP) region of the degenerated IVD in both pre-clinical and clinical trials, using progenitor or primary cell sources. We previously demonstrated an ability for a polymer-peptide hydrogel, serving as a culture substrate, to promote adult NP cells to undergo a shift from a degenerative fibroblast-like state to a juvenile-like NP phenotype. In the current study, we evaluate the ability for this peptide-functionalized hydrogel to serve as a bioactive system for cell delivery, retention and preservation of a biosynthetic phenotype for primary IVD cells delivered to the rat caudal disc in an anular puncture degeneration model. Our data suggest that encapsulation of adult degenerative human NP cells in a stiff formulation of the hydrogel functionalized with laminin-mimetic peptides IKVAV and AG73 can promote cell viability and increased biosynthetic activity for this population in 3D culture in vitro. Delivery of the peptide-functionalized biomaterial with primary rat cells to the degenerated IVD supported NP cell retention and NP-specific protein expression in vivo, and promoted improved disc height index (DHI) values and endplate organization compared to untreated degenerated controls. The results of this study suggest the physical cues of this peptide-functionalized hydrogel can serve as a supportive carrier for cell delivery to the IVD. STATEMENT OF SIGNIFICANCE: Cell delivery into the degenerative intervertebral disc has been widely explored as a strategy to supplement the nucleus pulposus. The current work seeks to employ a biomaterial functionalized with laminin-mimetic peptides as a cell delivery scaffold in order to improve cell retention rates within the intradiscal space, while providing the delivered cells with biomimetic cues in order to promote phenotypic expression and increase biosynthetic activity. The use of the in situ crosslinkable material integrated with the native IVD, presenting a system with adequate physical properties to support a degenerative disc.

Development of a library of laminin-mimetic peptide hydrogels for control of nucleus pulposus cell behaviors.

The nucleus pulposus (NP) of the intervertebral disc plays a critical role in distributing mechanical loads to the axial skeleton. Alterations in NP cells and, consequently, NP matrix are some of the earliest changes in the development of disc degeneration. Previous studies demonstrated a role for laminin-presenting biomaterials in promoting a healthy phenotype for human NP cells from degenerated tissue. Here we investigate the use of laminin-mimetic peptides presented individually or in combination on a poly(ethylene) glycol hydrogel as a platform to modulate the behaviors of degenerative human NP cells. Data confirm that NP cells attach to select laminin-mimetic peptides that results in cell signaling downstream of integrin and syndecan binding. Furthermore, the peptide-functionalized hydrogels demonstrate an ability to promote cell behaviors that mimic that of full-length laminins. These results identify a set of peptides that can be used to regulate NP cell behaviors toward a regenerative engineering strategy.

Gains and Losses in Virtual Mentorship: A Descriptive Case Study of Undergraduate Mentees and Graduate Mentors in STEM Research during the COVID-19 Pandemic.

Participating in mentored undergraduate research experiences can improve students' grade point averages, retention, and job placement. Graduate students also benefit from serving as mentors, as they gain teaching and research management experience. In early 2020, the SARS-CoV-2 (COVID-19) pandemic caused many institutions to shut down physical work spaces and move research and teaching online. In this study, we explore how graduate student mentors and undergraduate student mentees at Washington University in St. Louis adapted to virtual research mentoring during the COVID-19 pandemic. We examined changes in mentoring methods, research productivity, and the impact on the future plans of both mentors and mentees across six science/engineering departments. Survey responses from 79 mentees and 38 mentors indicated that a majority of mentees were able to have meaningful and productive virtual mentoring experiences, while other mentors failed to adequately involve their mentees in continued mentoring. Focusing virtual research experiences on activities such as literature review and data analysis and collaborating on goal setting can serve as a way for mentors to engage mentees even when they are unable to access lab equipment. Data from the present study reveal opportunities and challenges of virtual mentoring and can be used to inform effective research mentoring practices in the future.

Control of adhesive ligand density for modulation of nucleus pulposus cell phenotype.

Cells of the nucleus pulposus have been observed to undergo a shift from their notochordal-like juvenile phenotype to a more fibroblast-like state with age and maturation. It has been demonstrated that culture of degenerative adult human nucleus pulposus cells upon soft (<1 kPa) full length laminin-containing hydrogel substrates promotes increased levels of a panel of markers associated with the juvenile nucleus pulposus cell phenotype. In the current work, we observed an ability to use soft polymeric substrates functionalized with short laminin-mimetic peptide sequences to recapitulate the behaviors elicited by soft, full-length laminin containing materials. Furthermore, our work suggests an ability to mimic features of soft systems through control of peptide density upon stiffer substrates. Specifically, results suggest that stiffer polymer-peptide hydrogel substrates can be used to promote the expression of a more juvenile-like phenotype for cells of the nucleus pulposus by reducing adhesive ligand presentation. Here we show how polymer stiffness combined with adhesive ligand presentation can be controlled to be supportive of nucleus pulposus cell phenotype and biosynthesis.

Verteporfin treatment controls morphology, phenotype, and global gene expression for cells of the human nucleus pulposus.

Cells of the nucleus pulposus (NP) are essential contributors to extracellular matrix synthesis and function of the intervertebral disc. With age and degeneration, the NP becomes stiffer and more dehydrated, which is associated with a loss of phenotype and biosynthetic function for its resident NP cells. Also, with aging, the NP cell undergoes substantial morphological changes from a rounded shape with pronounced vacuoles in the neonate and juvenile, to one that is more flattened and spread with a loss of vacuoles. Here, we make use of the clinically relevant pharmacological treatment verteporfin (VP), previously identified as a disruptor of yes-associated protein-TEA domain family member-binding domain (TEAD) signaling, to promote morphological changes in adult human NP cells in order to study variations in gene expression related to differences in cell shape. Treatment of adult, degenerative human NP cells with VP caused a shift in morphology from a spread, fibroblastic-like shape to a rounded, clustered morphology with decreased transcriptional activity of TEAD and serum-response factor. These changes were accompanied by an increased expression of vacuoles, NP-specific gene markers, and biosynthetic activity. The contemporaneous observation of VP-induced changes in cell shape and prominent, time-dependent changes within the transcriptome of NP cells occurred over all timepoints in culture. Enriched gene sets with the transition to VP-induced cell rounding suggest a major role for cell adhesion, cytoskeletal remodeling, vacuolar lumen, and MAPK activity in the NP phenotypic and functional response to changes in cell shape.

Structural elucidation of cell membrane-derived nanoparticles using molecular probes.

Cell membrane-derived nanoparticles (CNPs) are a novel class of materials and are superior to synthetic nanomaterials in certain aspects due to their biological origin. Although their medical applications have been actively explored, the fundamental structure of CNPs is rarely studied. For example, the membrane orientation of CNPs is critical for their pharmacokinetics, but the previous characterizations were mostly qualitative. Herein, we report a method to quantitatively study membrane orientation of CNPs by using a 6-FAM ssDNA probe and a BHQ1 ssDNA quencher with a complementary sequence. This method utilizes specific DNA hybridization and fluorescence resonance energy transfer between 6-FAM and BHQ1. When ssDNA probes are conjugated on cell membranes, the probe marks the outer leaflet of cell membranes. The fluorescence intensities of particle solutions before and after the addition of the ssDNA quencher can be measured to quantitatively determine the fraction of CNPs with a correct outside-out (also called right-side-out) membrane orientation. Red blood cell membrane-derived nanoparticles (RBC-NPs) were fabricated and determined to have an 84% correct orientation. The quenching of membrane-bound nitrobenzoxadiazole (NBD) was used to study the permeability of RBC-NPs. It was found that RBC-NPs have a significantly higher permeability to the NBD quencher, dithionite ions, compared to live cells and egg PC/cholesterol liposomes. The ubiquitous methods using molecular probes can elucidate some structural properties of CNPs in general, enabling direct comparisons among CNPs that are derived from different cells and convenient optimization of particle fabrication.