Overcoming Historical Barriers: Enhancing Positive Perceptions of Medical Research Among African Americans Through a Conference-Based Workshop.

BACKGROUND: African Americans (AAs) and other racial/ethnic minority groups continue to be underrepresented in medical research and clinical trials. Failure to create more racially diverse research cohorts can exacerbate existing health disparities among these groups. OBJECTIVE: To investigate best practices and strategies for enhancing participation of AAs in medical research among attendees of a preconference Institute at a faith-based public health conference. DESIGN: Qualitative study using semi-structured interviews. PARTICIPANTS: A total of 21 out of 29 attendees (90% AA) of the Institute (72% response rate). APPROACH: A culturally tailored preconference Institute was held at the 2017 Healthy Churches 2020 National Conference. The Institute was led by AA researchers focused on underrepresentation of AAs in medical research. Semi-structured interviews were conducted 1-year post-Institute (n=21) and were audio-recorded, transcribed verbatim, and reviewed using thematic analysis. KEY RESULTS: The majority of attendees reported that they were more likely to participate in medical research after attending the Institute (75%). Salient learning points reported by attendees demonstrated attainment of the Institute objectives. Key themes emerged describing barriers preventing AAs from participating in medical research including fear/lack of trust, lack of information on research projects, and not being approached to participate. Key themes regarding facilitators for participation in medical research by AAs were clear communication of study objectives and research benefits along with trust in researchers. CONCLUSIONS: Attendees' perceptions of participation in medical research were largely positive following their attendance at a conference-based Institute aimed to address the underrepresentation of AAs in medical research. Our culturally tailored approach to disseminating knowledge of the research process could extend to other national conferences prioritizing AAs and other racial/ethnic minority populations to improve research participation.

In vivo genome editing using a high-efficiency TALEN system.

The zebrafish (Danio rerio) is increasingly being used to study basic vertebrate biology and human disease with a rich array of in vivo genetic and molecular tools. However, the inability to readily modify the genome in a targeted fashion has been a bottleneck in the field. Here we show that improvements in artificial transcription activator-like effector nucleases (TALENs) provide a powerful new approach for targeted zebrafish genome editing and functional genomic applications. Using the GoldyTALEN modified scaffold and zebrafish delivery system, we show that this enhanced TALEN toolkit has a high efficiency in inducing locus-specific DNA breaks in somatic and germline tissues. At some loci, this efficacy approaches 100%, including biallelic conversion in somatic tissues that mimics phenotypes seen using morpholino-based targeted gene knockdowns. With this updated TALEN system, we successfully used single-stranded DNA oligonucleotides to precisely modify sequences at predefined locations in the zebrafish genome through homology-directed repair, including the introduction of a custom-designed EcoRV site and a modified loxP (mloxP) sequence into somatic tissue in vivo. We further show successful germline transmission of both EcoRV and mloxP engineered chromosomes. This combined approach offers the potential to model genetic variation as well as to generate targeted conditional alleles.

Health Behaviors and Preventive Healthcare Utilization Among African-American Attendees at a Faith-Based Public Health Conference: Healthy Churches 2020.

Unhealthy eating habits and physical inactivity along with lack of access to quality healthcare contribute to the marked health disparities in chronic diseases among African-Americans. Faith-based public health conferences offer a potential opportunity to improve health literacy and change health behaviors through health promotion within this population, thereby reducing health disparities. This study examined the self-reported health behaviors and preventive healthcare utilization patterns of 77 participants at a predominantly African-American faith-based public health conference, Healthy Churches 2020. A self-administered questionnaire was distributed to a sample of attendees to assess their health behaviors (diet and physical activity), preventive healthcare utilization (annual healthcare provider visits), and health-promoting activities at their places of worship. The results indicate that attendees of a faith-based public health conference have adequate preventive healthcare utilization, but suboptimal healthy behaviors. Our findings support the need for ongoing health-promoting activities with an emphasis on diet and physical activity among this population.

A Community-Informed Virtual World-Based Cardiac Rehabilitation Program as an Extension of Center-Based Cardiac Rehabilitation: MIXED-METHODS ANALYSIS OF A MULTICENTER PILOT STUDY.

PURPOSE: Innovative methods for delivering cardiac rehabilitation (CR) that provide strategies to circumvent the mounting barriers to traditional CR have the potential to widen access to a well-established secondary prevention strategy. Our study assesses the feasibility and acceptability of a novel virtual world-based CR (VWCR) program, Destination Rehab , as an extension of a conventional center-based CR program. METHODS: Adult cardiac patients hospitalized at Mayo Clinic hospitals with a diagnosis for CR and ≥1 modifiable, lifestyle risk factor target-sedentary lifestyle (<3 hr physical activity/wk), unhealthy diet (<5 servings fruits and vegetables/d), or current smoking (>1 yr)-were recruited. Patients participated in an 8-wk health education program using a virtual world (VW) platform from a prior proof-of-concept study and a post-intervention focus group. Primary outcome measures included feasibility and acceptability. Secondary outcome measures included changes from baseline to post-intervention in cardiovascular (CV) health behaviors and biometrics, CV health knowledge, and psychosocial factors. RESULTS: Of the 30 enrolled patients (age 59.1 ± 9.7 yr; 50% women), 93% attended ≥1 session and 71% attended ≥75% of sessions. The overall VWCR experience received an 8 rating (scale 0-10) and had high acceptability. Clinically relevant trends were noted in CV health behaviors and biometrics, although not statistically significant. CONCLUSIONS: The VWCR program is a feasible, highly acceptable, and innovative platform to potentially influence health behaviors and CV risk and may increase accessibility to disadvantaged populations with higher CV disease burdens.

Non-Smad transforming growth factor-ß signaling regulated by focal adhesion kinase binding the p85 subunit of phosphatidylinositol 3-kinase.

TGF-ß modulates numerous diverse cellular phenotypes including growth arrest in epithelial cells and proliferation in fibroblasts. Although the Smad pathway is fundamental for the majority of these responses, recent evidence indicates that non-Smad pathways may also have a critical role. Here we report a novel mechanism whereby the nonreceptor tyrosine focal adhesion kinase (FAK) functions as an adaptor necessary for cell type-specific responses to TGF-ß. We show that in contrast to Smad actions, non-Smad pathways, including c-Abl, PAK2, and Akt, display an obligate requirement for FAK. Interestingly, this occurs in Src null SYF cells and is independent of FAK tyrosine phosphorylation, kinase activity, and/or proline-rich sequences in the C-terminal FAT domain. FAK binds the phosphatidylinositol 3-kinase (PI3K) p85 regulatory subunit following TGF-ß treatment in a subset of fibroblasts but not epithelial cells and has an obligate role in TGF-ß-stimulated anchorage-independent growth and migration. Together, these results uncover a new scaffolding role for FAK as the most upstream component regulating the profibrogenic action of TGF-ß and suggest that inhibiting this interaction may be useful in treating a number of fibrotic diseases.

Addressing community health needs through community engagement research advisory boards.

Over 80% of CTSA programs have a community advisory board (CAB). Little is known about how research discussed with CABs aligns with community priorities (bidirectionality). This program evaluation assessed researcher presentations from 2014 to 2018 to the CABs linked to our CTSA at all three sites (Minnesota, Arizona, and Florida) for relevance to local community needs identified in 2013 and/or 2016. From content analysis, of 65 presentations total, 41 (63%) addressed ≥1 local health needs (47% Minnesota, 60% Florida, and 80% Arizona). Cross-cutting topics were cancer/cancer prevention (physical activity/obesity/nutrition) and mental health. Results could help to prioritize health outcomes of community-engaged research efforts.

Internalization-dependent and -independent requirements for transforming growth factor beta receptor signaling via the Smad pathway.

Members of the transforming growth factor beta (TGF-beta) family of proteins signal through cell surface transmembrane serine/threonine protein kinases known as type I and type II receptors. The TGF-beta signal is extended through phosphorylation of receptor-associated Smad proteins by the type I receptor. Although numerous investigations have established the sequence of events in TGF-beta receptor (TGF-beta R) activation, none have examined the role of the endocytic pathway in initiation and/or maintenance of the signaling response. In this study we investigated whether TGF-beta R internalization modulates type I receptor activation, the formation of a functional receptor/Smad/SARA complex, Smad2/3 phosphorylation or nuclear translocation, and TGF-beta-dependent reporter gene activity. Our data provide evidence that, whereas type I receptor phosphorylation and association of SARA and Smad2 with the TGF-beta R complex take place independently of clathrin lattice formation, Smad2 or Smad3 activation and downstream signaling only occur after endocytic vesicle formation. Thus, TGF-beta R endocytosis is not simply a way to dampen the signaling response but instead is required to propagate signaling via the Smad pathway.

Transforming growth factor-beta activation of phosphatidylinositol 3-kinase is independent of Smad2 and Smad3 and regulates fibroblast responses via p21-activated kinase-2.

Transforming growth factor-beta (TGF-beta) stimulates cellular proliferation and transformation to a myofibroblast phenotype in vivo and in a subset of fibroblast cell lines. As the Smad pathway is activated by TGF-beta in essentially all cell types, it is unlikely to be the sole mediator of cell type-specific outcomes to TGF-beta stimulation. In the current study, we determined that TGF-beta receptor signaling activates phosphatidylinositol 3-kinase (PI3K) in several fibroblast but not epithelial cultures independently of Smad2 and Smad3. PI3K activation occurs in the presence of dominant-negative dynamin and is required for p21-activated kinase-2 kinase activity and the increased proliferation and morphologic change induced by TGF-beta in vitro.

Type II transforming growth factor-beta receptor recycling is dependent upon the clathrin adaptor protein Dab2.

Transforming growth factor (TGF)-ß family proteins form heteromeric complexes with transmembrane serine/threonine kinases referred to as type I and type II receptors. Ligand binding initiates a signaling cascade that generates a variety of cell type-specific phenotypes. Whereas numerous studies have investigated the regulatory activities controlling TGF-ß signaling, there is relatively little information addressing the endocytic and trafficking itinerary of TGF-ß receptor subunits. In the current study we have investigated the role of the clathrin-associated sorting protein Disabled-2 (Dab2) in TGF-ß receptor endocytosis. Although small interfering RNA-mediated Dab2 knockdown had no affect on the internalization of various clathrin-dependent (i.e., TGF-ß, low-density lipoprotein, or transferrin) or -independent (i.e., LacCer) cargo, TGF-ß receptor recycling was abrogated. Loss of Dab2 resulted in enlarged early endosomal antigen 1-positive endosomes, reflecting the inability of cargo to traffic from the early endosome to the endosomal recycling compartment and, as documented previously, diminished Smad2 phosphorylation. The results support a model whereby Dab2 acts as a multifunctional adaptor in mesenchymal cells required for TGF-ß receptor recycling as well as Smad2 phosphorylation.

Erbin and the NF2 tumor suppressor Merlin cooperatively regulate cell-type-specific activation of PAK2 by TGF-beta.

Transforming growth factor beta (TGF-beta) family ligands are pleotropic proteins with diverse cell-type-specific effects on growth and differentiation. For example, PAK2 activation is critical for the proliferative/profibrotic action of TGF-beta on mesenchymal cells, and yet it is not responsive to TGF-beta in epithelial cells. We therefore investigated the regulatory constraints that prevent inappropriate PAK2 activation in epithelial cultures. The results show that the epithelial-enriched protein Erbin controls the function of the NF2 tumor suppressor Merlin by determining the output of Merlin's physical interactions with active PAK2. Whereas mesenchymal TGF-beta signaling induces PAK2-mediated inhibition of Merlin function in the absence of Erbin, Erbin/Merlin complexes bind and inactivate GTPase-bound PAK2 in epithelia. These results not only identify Erbin as a key determinant of epithelial resistance to TGF-beta signaling, they also show that Erbin controls Merlin tumor suppressor function by switching the functional valence of PAK2 binding.

Halothane does not inhibit the functional coupling between the beta2-adrenergic receptor and the Galphas heterotrimeric G protein.

BACKGROUND: This study investigated whether halothane affects the functional coupling between the beta2 adrenergic receptor and the alpha subunit of its cognate stimulatory heterotrimeric guanosine-5'-triphosphate (GTP)-binding protein (Galphas). The authors hypothesized that halothane does not affect isoproterenol-promoted guanosine nucleotide exchange at Galphas and hence would not affect isoproterenol-induced relaxation of airway smooth muscle. METHODS: Halothane effects on isoproterenol-induced inhibition of calcium sensitivity were measured in permeabilized porcine airway smooth muscle. Galphas nucleotide exchange was measured in crude membranes prepared from COS-7 cells transfected to transiently coexpress the human beta1 or beta2 receptor each with human short Galphas. A radioactive, nonhydrolyzable analog of GTP, [S]GTPgammaS, was used as the reporter for nucleotide exchange at Galphas. RESULTS: Halothane (0.75 mm, approximately 2.8 minimum alveolar concentration [MAC] in pigs) did not affect isoproterenol-induced inhibition of calcium sensitivity. Isoproterenol caused a time- and concentration-dependent increase in Galphas nucleotide exchange. Halothane, even at concentrations of 1.5 mm (approximately 5.6 MAC), had no effect on basal Galphas nucleotide exchange in the absence of isoproterenol, whereas halothane inhibited isoproterenol-promoted Galphas nucleotide exchange in both the beta1-Galphas and beta2-Galphas expressing membranes. However, the effect was significantly greater on beta1-Galphas coupling compared with beta2-Galphas coupling, with no effect on beta2-Galphas coupling at 2.8 MAC halothane. CONCLUSION: Halothane does not inhibit the biochemical coupling between the beta2 receptor and Galphas and hence does not affect the inhibition of calcium sensitivity induced by isoproterenol. Therefore, halothane should not affect the efficacy of beta2 agonists, as suggested by studies of in vivo animal models of asthma.

Differential effects of volatile anesthetics on M3 muscarinic receptor coupling to the Galphaq heterotrimeric G protein.

BACKGROUND: Halothane inhibits airway smooth muscle contraction in part by inhibiting the functional coupling between muscarinic receptors and one of its cognate heterotrimeric G proteins, Galphaq. Based on previous studies indicating a more potent effect of halothane and sevoflurane on airway smooth muscle contraction compared with isoflurane, the current study hypothesized that at anesthetic concentrations of 2 minimum alveolar concentration (MAC) or less, halothane and sevoflurane but not isoflurane inhibit acetylcholine-promoted Galphaq guanosine nucleotide exchange. METHODS: Galphaq guanosine nucleotide exchange was measured in crude membranes prepared from COS-7 cells transiently coexpressing the human M3 muscarinic receptor and human Galphaq. A radioactive, nonhydrolyzable analog of guanosine-5'-triphosphate, [35S]GTPgammaS, was used as a reporter for nucleotide exchange at Galphaq. RESULTS: Acetylcholine caused a concentration-dependent increase in Galphaq [35S]GTPgammaS-GDP exchange. Neither anesthetic affected constitutive Galphaq [35S]GTPgammaS-GDP exchange in the absence of acetylcholine. Conversely, each anesthetic caused a concentration-dependent and reversible inhibition of Galphaq [35S]GTPgammaS-GDP exchange when promoted by acetylcholine. At concentrations of 3 MAC or less, the effect of halothane and sevoflurane were significantly greater than that of isoflurane, with only a minimal inhibition by isoflurane observed at 2 MAC. CONCLUSION: The differential effects of volatile anesthetics on acetylcholine-promoted guanosine nucleotide exchange at Galphaq are consistent with the apparent more potent direct effect of halothane and sevoflurane compared with isoflurane on muscarinic receptor-mediated contraction of isolated airway smooth muscle. These differential effects also suggest a mode of anesthetic action that could be due to anesthetic-protein interactions and not simply anesthetic accumulation in the lipid membrane.

Effect of halothane on galphai-3 and its coupling to the M2 muscarinic receptor.

BACKGROUND: Halothane is an effective bronchodilator and inhibits airway smooth muscle contraction in part by inhibiting intracellular signaling pathways activated by the M2 muscarinic receptor and its cognate inhibitory heterotrimeric guanosine-5'-triphosphate (GTP)-binding protein (G protein), Gi. This study hypothesized that halothane inhibits nucleotide exchange at the alpha isoform-3 subunit of Gi (Galphai-3), but only when regulated by the M2 muscarinic receptor. METHODS: GTP hydrolysis by Galphai-3 and the Galphai-3beta1gamma2HF heterotrimer expressed in Spodoptera frugiperda cells was measured using a phosphohydrolase assay with [gammaPi]-labeled GTP. Anesthetic binding to Galphai-3 was measured by saturation transfer difference nuclear magnetic resonance spectroscopy. Galphai-3 nucleotide exchange was measured in crude membranes prepared from COS-7 cells transiently coexpressing the M2 muscarinic receptor and Galphai-3. A radioactive analog of GTP, [S]GTPgammaS, was used as a reporter for Galphai-3 nucleotide exchange. RESULTS: Although spectroscopy demonstrated halothane binding to Galphai-3, this binding had no effect on [gammaPi]-labeled GTP hydrolysis by the Galphai-3beta1gamma2HF heterotrimer expressed in Spodoptera frugiperda cells, nor basal Galphai-3 nucleotide exchange measured in crude membranes when the muscarinic receptor agonist acetylcholine was omitted from the assay. Conversely, halothane caused a concentration-dependent inhibition of Galphai-3 nucleotide exchange with acetylcholine included in the assay. CONCLUSION: These data indicate that despite halothane binding to Galphai-3, halothane has no direct inhibitory effect on the intrinsic activity of the Galphai-3beta1gamma2HF heterotrimer but inhibits M2 muscarinic receptor regulation of the heterotrimer. This novel effect is consistent with the ability of halothane to inhibit airway smooth muscle contraction and bronchoconstriction induced by acetylcholine.