Expression of the DNA/RNA helicase schlafen family member 11 (SLFN11) has been identified as a sensitizer of tumor cells to DNA-damaging agents including platinum chemotherapy. We assessed the impact of SLFN11 expression on response to platinum chemotherapy and outcomes in patients with metastatic castration-resistant prostate cancer (CRPC). Tumor expression of SLFN11 was assessed in 41 patients with CRPC treated with platinum chemotherapy by RNA sequencing (RNA-seq) of metastatic biopsy tissue (n = 27) and/or immunofluorescence in circulating tumor cells (CTC; n = 20). Cox regression and Kaplan–Meier methods were used to evaluate the association of SLFN11 expression with radiographic progression-free survival (rPFS) and overall survival (OS). Multivariate analysis included tumor histology (i.e., adenocarcinoma or neuroendocrine) and the presence or absence of DNA repair aberrations. Patient-derived organoids with SLFN11 expression and after knockout by CRISPR-Cas9 were treated with platinum and assessed for changes in dose response. Patients were treated with platinum combination (N = 38) or platinum monotherapy (N = 3). Median lines of prior therapy for CRPC was two. Median OS was 8.7 months. Overexpression of SLFN11 in metastatic tumors by RNA-seq was associated with longer rPFS compared with those without overexpression (6.9 vs. 2.8 months, HR = 3.72; 95% confidence interval (CI), 1.56–8.87; P < 0.001); similar results were observed for patients with SLFN11-positive versus SLFN11-negative CTCs (rPFS 6.0 vs. 2.2 months, HR = 4.02; 95% CI, 0.77–20.86; P = 0.002). A prostate-specific antigen (PSA) decline of ≥50% was observed in all patients with SLFN11 overexpression. No association was observed between SLFN11 expression and OS. On multivariable analysis, SLFN11 was an independent factor associated with rPFS on platinum therapy. Platinum response of organoids expressing SLFN11 was reduced after SLFN11 knockout. Our data suggest that SLFN11 expression might identify patients with CRPC with a better response to platinum chemotherapy independent of histology or other genomic alterations. Additional studies, also in the context of PARP inhibitors, are warranted.

KRAS mutation is a negative predictive biomarker of anti-EGFR agents in patients with metastatic colorectal cancer (mCRC), and remains an elusive target. Pelareorep, a double-stranded RNA virus selectively replicates in KRAS-mutated cells, and is synergistic with irinotecan. A dose escalation trial of FOLFIRI/bevacizumab [irinotecan (150–180 mg/m²) and pelareorep (1 x 10¹⁰ TCID₅₀–3 x 10¹⁰ TCID₅₀)] was implemented in adult patients with oxaliplatin refractory/intolerant, KRAS-mutant mCRC. Pelareorep was administered intravenously over 1 hour on days 1–5 every 4 weeks. Additional studies included pharmacokinetics, tumor morphology, and immune responses. Among FOLFIRI-naïve patients, the highest dose of FOLFIRI/bevacizumab (180 mg/m² irinotecan) and pelareorep (3 x 10¹⁰ TCID₅₀) was well tolerated, without a dose-limiting toxicity. At the recommended phase II dose, 3 of 6 patients (50%) had a partial response; the median progression-free and overall survival (PFS, OS) were 65.6 weeks and 25.1 months, respectively. Toxicities included myelosuppression, fatigue, and diarrhea. Transmission electron microscopy revealed viral factories (viral collections forming vesicular structures), at various stages of development. Immunogold staining against viral capsid -1 protein demonstrated viral "homing" in the tumor cells. The nucleus displayed sufficient euchromatin regions suggestive of active transcription. Flow cytometry revealed rapid dendritic cell maturation (48 hours) with subsequent activation of cytotoxic T cells (7 days). The combination of pelareorep with FOLFIRI/bevacizumab is safe. The PFS and OS data are encouraging and deserve further exploration. Pelareorep leads to a clear recurrent immune stimulatory response with cytotoxic T-cell activation, and homes and replicates in the tumor.

The development of efficacious therapies targeting metastatic spread of breast cancer to the brain represents an unmet clinical need. Accordingly, an improved understanding of the molecular underpinnings of central nervous system spread and progression of breast cancer brain metastases (BCBM) is required. In this study, the clinical burden of disease in BCBM was investigated, as well as the role of aldehyde dehydrogenase 1A3 (ALDH1A3) in the metastatic cascade leading to BCBM development. Initial analysis of clinical survival trends for breast cancer and BCBM determined improvement of breast cancer survival rates; however, this has failed to positively affect the prognostic milestones of triple-negative breast cancer (TNBC) brain metastases (BM). ALDH1A3 and a representative epithelial–mesenchymal transition (EMT) gene signature (mesenchymal markers, CD44 or Vimentin) were compared in tumors derived from BM, lung metastases (LM), or bone metastases (BoM) of patients as well as mice after injection of TNBC cells. Selective elevation of the EMT signature and ALDH1A3 were observed in BM, unlike LM and BoM, especially in the tumor edge. Furthermore, ALDH1A3 was determined to play a role in BCBM establishment via regulation of circulating tumor cell adhesion and migration phases in the BCBM cascade. Validation through genetic and pharmacologic inhibition of ALDH1A3 via lentiviral shRNA knockdown and a novel small-molecule inhibitor demonstrated selective inhibition of BCBM formation with prolonged survival of tumor-bearing mice. Given the survival benefits via targeting ALDH1A3, it may prove an effective therapeutic strategy for BCBM prevention and/or treatment.

TNF-related apoptosis-inducing ligand (TRAIL) and an agonistic antibody against the death-inducing TRAIL receptor 5, DR5, are thought to selectively induce tumor cell death and therefore, have gained attention as potential therapeutics currently under investigation in several clinical trials. However, some tumor cells are resistant to TRAIL/DR5–induced cell death, even though they express DR5. Previously, we reported that DR5 is transported into the nucleus by importin β1, and knockdown of importin β1 upregulates cell surface expression of DR5 resulting in increased TRAIL sensitivity in vitro. Here, we examined the impact of importin β1 knockdown on agonistic anti-human DR5 (hDR5) antibody therapy. Drug-inducible importin β1 knockdown sensitizes HeLa cells to TRAIL-induced cell death in vitro, and exerts an antitumor effect when combined with agonistic anti-hDR5 antibody administration in vivo. Therapeutic importin β1 knockdown, administered via the atelocollagen delivery system, as well as treatment with the importin β inhibitor, importazole, induced regression and/or eradication of two human TRAIL-resistant tumor cells when combined with agonistic anti-hDR5 antibody treatment. Thus, these findings suggest that the inhibition of importin β1 would be useful to improve the therapeutic effects of agonistic anti-hDR5 antibody against TRAIL-resistant cancers.

Dysregulation of DNA methylation is an established feature of breast cancers. DNA demethylating therapies like decitabine are proposed for the treatment of triple-negative breast cancers (TNBC) and indicators of response need to be identified. For this purpose, we characterized the effects of decitabine in a panel of 10 breast cancer cell lines and observed a range of sensitivity to decitabine that was not subtype specific. Knockdown of potential key effectors demonstrated the requirement of deoxycytidine kinase (DCK) for decitabine response in breast cancer cells. In treatment-naïve breast tumors, DCK was higher in TNBCs, and DCK levels were sustained or increased post chemotherapy treatment. This suggests that limited DCK levels will not be a barrier to response in patients with TNBC treated with decitabine as a second-line treatment or in a clinical trial. Methylome analysis revealed that genome-wide, region-specific, tumor suppressor gene–specific methylation, and decitabine-induced demethylation did not predict response to decitabine. Gene set enrichment analysis of transcriptome data demonstrated that decitabine induced genes within apoptosis, cell cycle, stress, and immune pathways. Induced genes included those characterized by the viral mimicry response; however, knockdown of key effectors of the pathway did not affect decitabine sensitivity suggesting that breast cancer growth suppression by decitabine is independent of viral mimicry. Finally, taxol-resistant breast cancer cells expressing high levels of multidrug resistance transporter ABCB1 remained sensitive to decitabine, suggesting that the drug could be used as second-line treatment for chemoresistant patients.

2-fluorofucose (2FF) inhibits protein and cellular fucosylation. Afucosylation of IgG antibodies enhances antibody-dependent cell-mediated cytotoxicity by modulating antibody affinity for FcRIIIa, which can impact secondary T-cell activation. Immune responses toward most common solid tumors are dominated by a humoral immune response rather than the presence of tumor-infiltrating cytotoxic T cells. IgG antibodies directed against numerous tumor-associated proteins are found in the sera of both patients with breast cancer and transgenic mice bearing mammary cancer. We questioned whether 2FF would have antitumor activity in two genetically distinct transgenic models; TgMMTV-neu (luminal B) and C3(1)-Tag (basal) mammary cancer. 2FF treatment significantly improved overall survival. The TgMMTV-neu doubled survival time compared with controls [P < 0.0001; HR, 7.04; 95% confidence interval (CI), 3.31–15.0], and survival was significantly improved in C3(1)-Tag (P = 0.0013; HR, 3.36; 95% CI, 1.58–7.14). 2FF treated mice, not controls, developed delayed-type hypersensitivity and T-cell responses specific for syngeneic tumor lysates (P < 0.0001). Serum IgG from 2FF-treated mice enhanced tumor lysis more efficiently than control sera (P = 0.004). Administration of 2FF for prophylaxis, at two different doses, significantly delayed tumor onset in both TgMMTV-neu; 20 mmol/L (P = 0.0004; HR, 3.55; 95% CI, 1.60–7.88) and 50 mmol/L (P = 0.0002; HR: 3.89; 95% CI, 1.71–8.86) and C3(1)-Tag; 20 mmol/L (P = 0.0020; HR, 2.51; 95% CI, 1.22–5.18), and 50 mmol/L (P = 0.0012; HR, 3.36; 95% CI, 1.57–7.18). Mammary cancer was prevented in 33% of TgMMTV-neu and 26% of C3(1)-Tag. 2FF has potent antitumor effects in mammary cancer models. The agent shows preclinical efficacy for both cancer treatment and prevention.

Physical and chemical DNA-damaging agents are used widely in the treatment of cancer. Double-strand break (DSB) lesions in DNA are the most deleterious form of damage and, if left unrepaired, can effectively kill cancer cells. DNA-dependent protein kinase (DNA-PK) is a critical component of nonhomologous end joining (NHEJ), one of the two major pathways for DSB repair. Although DNA-PK has been considered an attractive target for cancer therapy, the development of pharmacologic DNA-PK inhibitors for clinical use has been lagging. Here, we report the discovery and characterization of a potent, selective, and orally bioavailable DNA-PK inhibitor, M3814 (peposertib), and provide in vivo proof of principle for DNA-PK inhibition as a novel approach to combination radiotherapy. M3814 potently inhibits DNA-PK catalytic activity and sensitizes multiple cancer cell lines to ionizing radiation (IR) and DSB-inducing agents. Inhibition of DNA-PK autophosphorylation in cancer cells or xenograft tumors led to an increased number of persistent DSBs. Oral administration of M3814 to two xenograft models of human cancer, using a clinically established 6-week fractionated radiation schedule, strongly potentiated the antitumor activity of IR and led to complete tumor regression at nontoxic doses. Our results strongly support DNA-PK inhibition as a novel approach for the combination radiotherapy of cancer. M3814 is currently under investigation in combination with radiotherapy in clinical trials.

Detailed landform mapping of key areas in the Vale of Pickering, supported by LiDAR interpretation, has produced sufficient evidence to establish a reinterpretation of the Mid to Late Pleistocene chronology of the Vale of Pickering by defining the margins of two temporally distinct proglacial lakes and reaching a new understanding of the origin of some well-documented geomorphological features. The main significance of the mapping has been to establish that the Hutton Buscel terrace probably originated by lateral erosion along the southern edge of the Corallian Group dip slope of the North York Moors prior to deposition of a broad alluvial plain below a 70 m strandline. Traces of a comparable feature were also located below the Chalk Group escarpment on the southern side of the Vale of Pickering. Perhaps of equal significance has been confirmation that the younger of the two lakes, which has a 45 m shoreline, was possibly connected to Lake Humber in the Vale of York through the Derwent Valley. Evidence for such a lake was provided by mapped shorelines at Malton and Pickering that appear compatible with shorelines in Lake Humber. To account for deep erosion of the Derwent and Mere valleys and the occurrence of laminated clays at c. 65 m, below a 70 m shoreline above Crambe, regional uplift has been evoked post the older 70 m lake. In-valley alluvial fans have been mapped for the first time in Newton Dale and Thornton Dale.

The invertebrate trace fossils Selenichnites rossendalensis and Crescentichnus tesiltus are recorded and described from the Middle Jurassic Gristhorpe Member of the Cloughton Formation of the Cleveland Basin. This is the first record of these ichnospecies from the basin and now completes the occurrence of these and other traces assumed to have been made by limulids from all three non-marine formations of the Ravenscar Group.

Field evidence shows that emplacement of Devonian granites in northern England overlaps in space and time with the end of the supposed Acadian deformation in their country rocks. The age of this Acadian event in England and Wales is in need of review because of revised Rb-Sr and K-Ar decay constants and recently acquired radiometric ages on the granites.

Published K-Ar and Ar-Ar cleavage ages recalculated to the new decay constants range from 404 to 394 Ma (Emsian, Early Devonian). Emplacement of the Skiddaw and Weardale granites at 398.8 ± 0.4 and 399.3 ± 0.7 Ma respectively is indicated by U-Pb zircon ages, and is compatible with the field evidence. However, emplacement of the Shap Granite at a Re-Os molybdenite age of 405.2 ± 1.8 Ma and at the youngest U-Pb zircon age of 403 ± 8 Ma matches the field evidence less well. The apparent paradox in these ages is resolved if the K-Ar ages record only the end of millions of years of cleavage formation. An earlier cluster of K-Ar and Ar-Ar cleavage ages at 426–420 Ma (Ludlow to Přídolí, late Silurian) dates a pre-Acadian resetting event soon after Iapetus closure, an event of uncertain significance.

Ion microprobe U-Pb zircon ages for the Shap Granite have a mean of 415.6 ± 1.4 Ma but a range of 428–403 Ma, compatible with a long magmatic history. Thermal considerations suggest that this history was not at the upper crustal emplacement site but in a mid-crustal mush zone, now preserved at about 10 km depth as a component of the Lake District and North Pennine batholiths.

Oil residues occur as solid bitumen in mineralized zones within the Devonian Weardale Granite of the northern Pennines, northern England. Comparable residues are present in the overlying Mississippian rocks and were probably derived from a Carboniferous source, i.e. during later mineralization of the granite. The bitumen was already solidified during fluorite mineralization, which does not contain oil inclusions. The residues do not show the high thermal maturity of organic matter in the region altered by the earliest Permian Whin Sill. Like the sulphide-fluorite mineralization, oil emplacement post-dated intrusion of the sill. Pyrite associated with the oil residues is enriched in trace elements including lead, silver, gold, selenium and tellurium, which suggests that mineralizing fluids at least shared pathways with migrating hydrocarbons and possibly also suggests undiscovered valuable metal resources.

Commonly used model teeth are so far uniform in color and hardness. There is no discrimination between enamel and dentin part of a tooth. This condition makes it difficult to train a preparation technique, which is adapted to real tooth substance. The aim of this study was to design and establish a 3D printed tooth with different layers for enamel and dentin for education in crown preparation. A printable tooth with different layers for enamel and dentin was designed, and all 38 fourth-year dental students in the first clinical course in prosthodontics and 30 experienced dentists were trained during a voluntary hands-on course in 2019. Prior to the study, the students had used standard model teeth and real-teeth models in their preclinical education. They had experience in caries removal and preparation on real patients. The perceived benefits of the 3D printed tooth were evaluated by a questionnaire. All individuals in both groups completed the questionnaire, for a 100% response rate. The results showed that the printed tooth was given an overall mean grade of 2.3 (students) and 2.0 (experts) on a scale from 1=excellent to 5=poor. The difference in hardness between the dentin and enamel layer was given a mean of 2.4 (students and experts) and the difference in color a 1.7 (students) and 1.8 (experts). The tooth model with the prepared tooth illustrating an ideal preparation was graded 1.6 (students and experts). In this study, the students had the opportunity to learn a correct crown preparation on a printed tooth with different material properties for enamel and dentin. The learning effect with this tooth model was rated as good on the questionnaire by both students and expert dentists.

This article describes the development of medical competencies for oral medicine specialty training in the UK and Ireland by a collaborative working group using a modified Delphi technique. The current specialty training curriculum for oral medicine (OM) in the UK was developed by a working group including members of the British Society for Oral Medicine (BSOM) and members of the Specialty Advisory Committee for Additional Dental Specialties (SACADS) and adopted by the UK General Dental Council (GDC) in 2010. When the curriculum was developed, the entry requirements for specialty training in OM included undergraduate degrees in both dentistry and medicine. At the time of adoption, the requirement for a medical degree was removed. Medical competencies were assumed to have been delivered in medical undergraduate and postgraduate training. Accordingly, there was a need to define the medical competencies for OM specialty training to benefit trainees, trainers, and assessors. In 2018, a group comprising specialty trainers, recent former specialty trainees, and current specialty trainees in OM held face-to-face meetings in addition to email discussions and developed an updated curriculum document to better reflect the medical competencies required in specialty training. A collaborative modified Delphi approach was used to evaluate medical foundation competencies and to include only those that were considered relevant to OM specialty training. A list of relevant and achievable medical competencies was determined that has been approved by SACADS and will be incorporated into a revised OM curriculum from the UK GDC. The newly agreed-upon document for medical competencies in OM specialty training will serve as a reference for trainees, trainers, and assessors and reflects a successful use of a modified Delphi approach.

The aims of this study were to qualitatively assess dental public health (DPH) residents’ perspectives on teaching methods for DPH competencies and to develop and implement a case-based simulation to address those competencies, constructed on the basis of the qualitative assessment. Focus group discussions were conducted with 18 DPH residents enrolled in two university-based DPH programs. Topic areas discussed in the two focus groups were perceived value of DPH competencies, ways to acquire new DPH skills/abilities, and additional skills/abilities needed by DPH residents. The focus groups’ responses showed that the residents felt competent in the analytical thinking competencies such as research methodology and critiquing literature. They emphasized the importance of learning leadership skills and reported feeling somewhat uncertain about their mastery of the policy and advocacy and system evaluation competencies. Of the two distinct categories of DPH skills and competencies— analytical/critical thinking and practical competencies—these residents reported that a greater proportion of time needed to be devoted to integrating the practical competencies into their education. Based on the residents’ feedback, the authors developed a structured seminar series taking a case-based approach to simulate real-world DPH problems, using real and semi-hypothetical planning projects to meet the residents’ perceived needs and covering gaps between didactic learning and practice.

Dental students’ ability to critique team performance in dental school team clinics is a key component of dental education. The aim of this study was to determine if students’ perceptions of their team leaders’ openness of communication, cooperative decision making, and well-defined goals were positively related to the students’ improvement-oriented voice behavior and willingness to raise concerns in the clinical environment. This study used a voluntary 12-question survey, distributed via email to all 311 students at the University of Nevada, Las Vegas School of Dental Medicine after completion of the spring 2017 semester. Eighty-seven students responded, for a response rate of 28%. Responses were stratified by team, class year, and gender, and the quantitative distribution of answers to each question was correlated with each other. Team leader collaborative qualities, which included openness for communication, cooperative decision making, and well-defined goals, were found to have a significant positive relationship with students’ willingness to both raise concerns and make suggestions. Additionally, when measured by class year and gender, team differences in voice behavior assessment by students across the teams were found to be independent of class year, and no significant differences were found by gender. These results suggested that, to maintain high levels of communication, proper reporting of concerns, and a high standard of care, dental schools should encourage team leaders to enhance their capacity to present active collaborative behaviors in the school’s clinic. The study also highlighted potential opportunities for further study of faculty traits and development in the dental school team model.

Dental students in North American dental schools are exposed to faculty members with various professional backgrounds. These faculty members may include dentists, dental hygienists, and scientists without clinical dental credentials. The practice of dental hygienists’ educating predoctoral dental students has not been well documented. The aims of this two-part study were to investigate the parameters of didactic, preclinical, and clinical instruction of dental students by dental hygienist faculty members in North American dental schools and to explore dental students’ perceptions of this form of teaching. In part one, a survey was sent electronically to the clinical or academic affairs deans of all 76 American Dental Education Association (ADEA) member dental schools in 2017. Twenty-nine responded, for a 38.2% response rate. In 76% of the responding schools, dental hygienists were teaching dental students. Most respondents reported that, in their schools, the minimum degree required to teach didactically was a master’s, while a bachelor’s degree was required for preclinical and clinical courses. There was no significant association between dental hygienists’ instructing dental students and having a dental hygiene educational program at the institution. In part two of the study, a questionnaire was completed by 102 graduating dental students (85% response rate) at one U.S. university to evaluate the impact of dental hygienist educators. Among the respondents, 87% reported feeling that dental hygienists were very effective educators. There were no significant differences in responses between traditional and advanced standing international dental students. This study found that dental hygienists were educating dental students in many North American dental schools and were doing so in curricular content beyond periodontics and that their educational contributions at a sample school were valued by the dental students there.

Few studies have been published on thesis completion experiences of master’s degree students. However, for doctoral students, dissertation completion has been found to be dependent on individual, relational, and institutional factors. The aim of this study was to examine dental hygienists’ perceptions of their experiences completing a thesis as a requirement for an advanced degree. A qualitative phenomenological research design was used utilizing virtual focus groups with a national purposive sample of dental hygienists (n=25) who had graduated from a degree program in which a thesis was a requirement for the degree. Data analysis used an inductive approach to identify themes using Liechty et al.’s framework of individual, relational, and institutional factors impacting completion of a dissertation. Liechty et al.’s framework is based on Vygotsky’s sociocultural theory of learning. In the results, individual factors identified included family/work responsibilities, lack of understanding of the thesis process, time management, health issues, and reaching personal and professional goals. Relational factors focused primarily on positive and negative experiences with the thesis advisor/committee and support from expert peers/family. Institutional factors included the thesis structure, financial concerns, and challenges in recruiting research participants. This study found many factors influencing the thesis experience that may help guide the process in graduate degree programs. In addition, the findings suggest a need to provide mentoring and support for thesis advisors and committee members to more effectively guide students through the thesis process. Effective modifications of these may improve retention of students and facilitate timely completion of thesis research.

Changes in U.S. health care delivery systems and Commission on Dental Accreditation standards provide impetus for interprofessional education (IPE) and collaborative practice, but roadmaps for engaging dental and dental hygiene faculty to incorporate IPE in a systematic manner are limited. The purpose of this report is to describe the process for creating a strategy and gathering a variety of baseline data to use for determining objectives and metrics and the subsequent development of an IPE strategic plan at the University of North Carolina (UNC) at Chapel Hill Adams School of Dentistry (SOD). SOD IPE committee members included representation from the UNC Schools of Dentistry, Medicine, Pharmacy, and Business. A three-phase framework was developed. Phase 1 (IPE assessment) was an internal environmental scan including a 2017 faculty survey, departmental mapping of IPE activities, comparison of UNC with national results on the IPE component of the American Dental Education Association (ADEA) survey of dental school seniors (2016 graduating class), identification of faculty joint/adjunct appointments at other UNC schools, and a strengths, weaknesses, opportunities, threats (SWOT) analysis. Phase 2 (visioning) consisted of development of IPE mission, vision, and priorities. In Phase 3 (implementation), priorities were developed. Data-gathering led to a strategic plan with three objectives: 1) increase faculty engagement and recognition, 2) develop predoctoral dentistry and dental hygiene IPE curricula, and 3) develop an infrastructure that supports IPE. Specific initiatives and activities, supporting metrics, and estimated costs were developed for each objective. The framework guided a systematic, transparent, and organized process for collecting and monitoring the evidence and directing activities. A three-year strategic plan for IPE was developed in 2017, and implementation is ongoing.

Clinical teaching is a cornerstone of health sciences education; it is also the most challenging aspect. The University of Pittsburgh Schools of Dental Medicine, Nursing, and Pharmacy developed a new evidence-based interprofessional course framed as a faculty learning community (FLC) around the principles of learning in a clinical environment. The aim of this study was to assess the overall effectiveness of this two-semester FLC at four health professions schools in academic year 2014-15. The assessment included anonymous participant surveys in each session and an anonymous end-of-course survey. Thirty-five faculty members from dental, health and rehabilitation sciences, nursing, and pharmacy enrolled in the FLC, with six to 32 enrollees attending each session. All attendees at each session completed the session evaluation surveys, but the attendance rate at each session ranged from 17.1% to 91.4%. Sixteen participants (46%) completed the end-of-course survey. The results showed overall positive responses to the FLC and changes in the participants’ self-reported knowledge. Session surveys showed that the participants found the FLC topics helpful and appreciated the opportunity to learn from each other and the interprofessional nature of the FLC. Responses to the end-of-course survey were in alignment with the individual session surveys and cited specific benefits as being the content, teaching materials, and structured discussions. In additional feedback, participants reported interest to continue as a cohort and to extend the peer-support system beyond the FLC. This outcomes assessment of the first round of the FLC confirmed that this cohort-based faculty development in an interprofessional setting was well received by its participants. Their feedback provided valuable insights for changes to future offerings.

The aim of this cross-sectional study was to examine the faculty mentoring practices in seven dental schools in the U.S. A 34-item survey was administered electronically to dental faculty members of all ranks, tracks, and job categories in seven dental schools using faculty listservs. Survey questions addressed current mentoring practices in which the faculty members were involved; their perceptions of those mentoring practices; their perceived characteristics of an ideal mentoring program, mentor, and mentee; perceived best practices; and respondents’ demographics. The survey was conducted from October 2017 to February 2018. A total of 154 surveys were completed (response rate 22%). Over 58% (90/154) of the respondents reported receiving no mentoring; 31.9% (49/154) said they received informal mentoring; and 9.7% (15/154) received formal mentoring. Of the 64 respondents who received mentoring, both formal and informal, 92.2% (59/64) were full-time faculty, and 7.8% (5/64) were part-time faculty (p=0.001). Approximately 39% of the respondents indicated that their mentoring program was not overseen by anyone and that participation was voluntary. The top three perceived benefits of mentoring were increased overall professional development, development of a career plan, and increased professional networks. The three most important characteristics of an ideal mentoring program for the respondents were a program based on the needs of the mentee, a mentor who has the desire to help the mentee, and a mentee who is eager to learn. The results of this study showed a very low level of formal or informal faculty mentoring programs in the dental schools surveyed. Future studies are needed to determine best practices and strategies to expand and enhance mentoring of faculty members.

The number of citations an article receives is an important indicator to quantify its influence in its field. The aim of this study was to identify and analyze the characteristics of the 50 top-cited articles addressing dental education published in two journals dedicated to dental education (European Journal of Dental Education and Journal of Dental Education). The Web of Science database was searched to retrieve the 50 most-cited articles from the two journals in December 2018. The top-cited articles were analyzed for journal of publication, number of citations, institution and country of origin, year of publication, study type, keywords, theme and subtheme, and international collaborations. The results showed the 50 top-cited articles were cited between 24 and 146 times each. The majority of these top-cited articles (n=34) were published in the Journal of Dental Education. Half (n=25) of the articles were by authors in the U.S. The most common study types were surveys (n=26) and reviews (n=10). The main themes of these top-cited articles were curriculum and learner characteristics. This bibliometric analysis can serve as a reference for recognizing studies with the most impact in the scholarship of dental education.

Despite advances in oral health care, inequalities in oral health outcomes persist due to problems in access. With proper training, primary care providers can mitigate this inequality by providing oral health education, screening, and referral to advanced dental treatment. Diverging sets of oral health competencies and guidelines have been released or endorsed by multiple primary care disciplines. The aim of this study was to transform multiple sets of competencies into Entrustable Professional Activities (EPAs) for oral health integration into primary care training. A scoping review of the literature between January 2000 and December 2016 was conducted according to PRISMA methodology to identify all existing sets of competencies. The following primary care disciplines were included in the search: allopathic/osteopathic medical schools and residency programs in family medicine, internal medicine, and pediatrics; physician assistant programs; and nurse practitioner programs. Competencies were compared using the Health Resources and Services Administration Integration of Oral Health and Primary Care Practice competencies as the foundational set and translated into EPAs. The resulting EPAs were tested with a reactor panel. The scoping review produced 1,466 references, of which 114 were selected for full text review. Fourteen competencies were identified as being central to the integration of oral health into primary care. These were converted to seven EPAs for oral health integration into primary care and were mapped onto Accreditation Council for Graduate Medical Education residency competency domains as well to the Association of American Medical Colleges EPAs for graduating medical students. The resulting EPAs delineate the essential, observable work required of primary care providers to ensure that oral health is treated as a critical determinant of overall health.

Interprofessional education (IPE) is based on collaborative practices that increase the occasions for communication among those in various health professions. However, there is a paucity of literature about the effectiveness of IPE programs in health professions education. The aim of this systematic review and meta-analysis was to objectively assess the literature on the effectiveness of IPE in improving health professions students’ attitudes after training. The major scholarly databases were searched for relevant IPE studies involving predoctoral health professions students. Two independent researchers selected the studies, extracted the data, and assessed the quality of the studies. Meta-analyses of the outcomes were performed using random effects models. Sixteen articles were ultimately selected for detailed review and meta-analysis. The meta-analysis showed that IPE training had a significant influence on students’ understanding of collaboration and resulted in better attitudes about interprofessional teamwork. Subscale analysis showed that one subscale score (roles and responsibilities) did not statistically significantly improve after IPE training (p=0.06), whereas the other four subscale items showed statistically significant improvements (p<0.01). The test for overall effects showed that IPE training had a significantly positive influence on students’ attitudes about IPE (Z=6.85, p<0.01). Subgroup results showed that medical students had more positive attitudes about IPE than did dental students. Regardless of profession, women students responded with significantly more positive feedback than did men students (p=0.02). These results suggest that intervention through IPE training has had positive effects in health professions education. Gender was an important factor impacting the outcomes of IPE. However, further clinical practice interventions may be helpful to enhance the IPE competence of health professions students.

Purpose: The purpose of this study was to identify current requirements for initial licensure and entry into the dental hygiene profession across state dental and dental hygiene licensing boards in the United States.Methods: A non-experimental study design was used to study dental and dental hygiene board licensing requirements in the United States, Puerto Rico and the Virgin Islands. Each regulatory board website was searched for requirements for entry-level dental hygiene licensure. Requirements were recorded on an Excel spreadsheet. State dental practice acts were reviewed to gather further information and 20 regulatory bodies were contacted to verify accuracy. Descriptive statistics were used to analyze data.Results: Information from a total of 52 dental boards (n=52) was examined for this study. Nearly all boards (n=51, 98.1%), with the exception of Alabama, required completion of entry-level education from a CODA accredited dental hygiene program and successful completion of the National Board Dental Hygiene Examination. Most states (n=51, 98.1%), except Delaware, also required a live-patient, a clinical board examination. Application fees ranged from $47.70 to $600. States varied considerably in terms of requirements for background checks, age, military status, and infection control training.Conclusion: Although the majority of regulatory bodies require completion of entry-level dental hygiene education from a CODA accredited program and successful completion of national board and a live-patient, clinical examination, there is considerable variation in other additional requirements for initial dental hygiene licensure.

Purpose: The purpose of this study was to determine strength of muscles involved with instrumentation (scaling) by dental hygienists and the additive effects of cellular (mobile) phone usage, as indicated by measurements of muscular force generation.Methods: A convenience sample of licensed dental hygienists currently in clinical practice (n=16) and an equal number of individuals not currently using devices/tools repetitively for work (n=16), agreed to participate in this pilot study. All participants completed a modified cell phone usage questionnaire to determine their use pattern and frequency. Upon completion of the questionnaire, participants' force production in six muscle groups was measured using a hand-held dynamometer. Descriptive statistics were used to analyze the data.Results: A total of 16 licensed dental hygienists (n=16) and 16 participants with no history of using tools/devices repetitively for work (n=16), comprised the experimental and control groups, repectively. The control group generated greater muscle force than the experimental group for the abductor pollicis longus (p=0.045). Significant differences were identified when comparing the low mobile phone users in the experimental group to the control group for the flexor pollicis brevis (p=0.031), abductor pollicis longus (p=0.031), and flexor digitorum (p=0.006), with the control group demonstrating higher muscle force. Years in clinical practice and mobile phone use was shown to have a significant effect on muscular force generation for the flexor pollicis brevis (F=3.645, df=3, p=0.020) and flexor digitorum (F=3.560, df=3, p=0.022); subjects who practiced dental hygiene the longest produced the least amount of muscle force.Conclusion: Results from this pilot study indicate there are no significant additive effects of cell phone use and dental hygiene practice on finger muscles used for instrumentation. However, results indicate that dental hygiene practice demonstrated significant effects on muscular strength as compared to individuals who do not use tools/devices repetitively for work. The small sample size may have impacted results and the study should be repeated with a larger sample.

Purpose: Untreated and poorly controlled diabetes causes increased levels of blood glucose associated with poor periodontal disease outcomes. Dental hygienists can play a significant role in screening patients for diabetes mellitus, leading to referral and early diagnosis. The purpose of this study was to determine the knowledge, attitudes, practices, and barriers faced by clinical dental hygienists regarding diabetes risk assessment and screenings.Methods: A mixed method design was used with a convenience sample of dental hygienists in clinical practice (n=316). A 32 item, electronic survey was validated at item-level, and participants were recruited through multiple dental hygiene Facebook groups. Descriptive statistics were used to analyze the data. The survey also included two open-ended attitude questions that were interpreted using thematic analysis to pinpoint common patterns within the data.Results: Dental hygienists had high knowledge scores regarding diabetes and oral health, although many were unaware of their states' specific statutes and regulations for screening practices. Nearly all (95.9%), were likely to educate and refer patients (82%), although fewer than half (40.9%), were likely to perform chairside screening for diabetes. Emergent themes for barriers to screening were time, money, patient acceptance/willingness, lack of education, not having the proper tools, and states' rules and regulations.Conclusion: Despite high knowledge scores regarding diabetes and oral health, there is a gap in regards to dental hygienists' willingness to perform diabetes screenings in a clinical setting. Dental hygienists should be capable of integrating chairside diabetes screening practices into the process of care with proper training.

Purpose: Measurement of dental plaque is frequently used as an indicator of overall oral health. The purpose of this study was to compare a manual (visual) plaque scoring system (University of Mississippi Oral Hygiene Index, UM-OHI) with an innovative automated digital scoring system.Methods: Mechanically ventilated, intensive care unit (ICU) patients (n=79) were the study population. Informed consent was given by the subject's legally authorized representative. Digital images of dental plaque were taken using an intraoral camera; and the quantity of dental plaque was scored using the UM-OHI and with a digitized automated scoring system. Distributions of dental plaque scores from both methods were plotted. Pearson correlation coefficients and intra-class coefficients were calculated between the two methods.Results: Participant mean age was 57.3 years; respiratory failure was the most prevalent admission diagnosis (55.7%). The mean percentage of dental plaque calculated by the manual method was found to be remarkably higher (67.3% ± 18.7%) than the percentage of dental plaque calculated by the automated scoring method (23.7% ± 15.2%) (p<0.0001). Despite remarkably different distributions of plaque scores, both the automated and manual scoring systems demostrated relatively high correlation (r=0.62) and good reliability (ICC=0.63).Conclusion: The automated digital scoring system resulted in a significantly lower overall percentage of total dental plaque as compared to the UM-OHI manual scoring system. While the automated digital scoring system may be more precise than a manual (visual) scoring system, its use should be weighed against the added effort, cost, and expertise required for the method. Further study is needed to determine whether an automated digital scoring system can be commercialized and is warranted for use outside of research settings.

Purpose: Oral and craniofacial conditions or diseases can impact an individual's health and quality of life. The purpose of this study was to assess the perceived oral health related quality of life (OHRQoL) of children, and evaluate the reported level of agreement between caregivers and their children.Methods: Purposive sampling was used to recruit children ages 8-15, and their caregivers from a dental clinic in a pediatric hospital for this descriptive, cross-sectional study. A modified version of a validated measure, Child Oral Health Impact Profile-Short Form (COHIP-SF), was used for a 22-item questionnaire encompassing three subscales: oral health, functional well-being, and social emotional well-being. Two additional items were included to assess child/caregiver's level of agreement. A dental chart review was also conducted to assess the child's overbite, overjet, and decayed surfaces. Data were analyzed through descriptive statistics and examined for assumptions of normality and linearity.Results: Sixty child/caregiver pairs (n=120) participated in this study. Overbite, overjet and decayed surfaces were not found to be related to any OHRQoL variable, including child/caregiver ratings and overall agreement (p>.05). Average OHRQoL scores for caregivers found to be more positive those of their children (p=.02). Agreement between caregivers and the child's gender was shown to be significant (p=.01). Female child scores differed significantly from males with respect to their caregiver responses (p=.02). Caregivers rated a higher OHRQoL for female children, thus overestimating their female child's reported OHRQoL.Conclusions: The moderate level of agreement found between children and caregivers reinforces the importance of including the child, as well as the caregiver, when assessing OHRQoL.

Purpose: The purpose of this study was to analyze associations between the oral health literacy of refugees and two oral health outcomes: dental care utilization and oral health self-efficacy.Methods: A convenience sample of refugees in the greater Los Angeles area attending English as a second language (ESL) classes sponsored by two refugee assistance organizations was used for this cross-sectional, correlational study. Participants responded to a questionnaire using items from the Health Literacy in Dentistry (HeLD) scale, in addition to items concerning dental care utilization and oral health self-efficacy. Descriptive statistics, chi-square and Fisher's Exact tests were used to analyze results.Results: Sixty-two refugees volunteered to participate (n=62). A majority of the respondents were female from Iraq or Syria, and selected the item “with little difficulty” for all oral health literacy tasks. In regards to dental care utilization, more than half of the respondents were considered high utilizers (63%, n=34) meaning they had visited a dental office within the last year; while a little more than one-third (37%, n=20), were low utilizers, indicating they had either never been to a dental office or it had been more than one year since they had dental treatment. Statistical analysis showed associations between oral health literacy and dental care utilization. However, few associations between oral health literacy and oral health self-efficacy were identified (p=0.0045).Conclusions: Results support the provision of easily obtainable and understandable oral health information to increase oral health literacy and dental care utilization among refugee populations. Future research is needed to examine the oral health literacy among refugees resettling in the United States.

Membrane-bound proteins have been proposed to mediate the transport of long-chain FA (LCFA) transport through the plasma membrane (PM). These proposals are based largely on reports that PM transport of LCFAs can be blocked by a number of enzymes and purported inhibitors of LCFA transport. Here, using the ratiometric pH indicator (2',7'-bis-(2-carboxyethyl)-5-(and-6-)-carboxyfluorescein and acrylodated intestinal FA-binding protein-based dual fluorescence assays, we investigated the effects of nine inhibitors of the putative FA transporter protein CD36 on the binding and transmembrane movement of LCFAs. We particularly focused on sulfosuccinimidyl oleate (SSO), reported to be a competitive inhibitor of CD36-mediated LCFA transport. Using these assays in adipocytes and inhibitor-treated protein-free lipid vesicles, we demonstrate that rapid LCFA transport across model and biological membranes remains unchanged in the presence of these purported inhibitors. We have previously shown in live cells that CD36 does not accelerate the transport of unesterified LCFAs across the PM. Our present experiments indicated disruption of LCFA metabolism inside the cell within minutes upon treatment with many of the "inhibitors" previously assumed to inhibit LCFA transport across the PM. Furthermore, using confocal microscopy and a specific anti-SSO antibody, we found that numerous intracellular and PM-bound proteins are SSO-modified in addition to CD36. Our results support the hypothesis that LCFAs diffuse rapidly across biological membranes and do not require an active protein transporter for their transmembrane movement.

Geranylgeranoic acid (GGA) originally was identified in some animals and has been developed as an agent for preventing second primary hepatoma. We previously have also identified GGA as an acyclic diterpenoid in some medicinal herbs. Recently, we reported that in human hepatoma-derived HuH-7 cells, GGA is metabolically labeled from ¹³C-mevalonate. Several cell-free experiments have demonstrated that GGA is synthesized through geranylgeranial by oxygen-dependent oxidation of geranylgeraniol (GGOH), but the exact biochemical events giving rise to GGA in hepatoma cells remain unclear. Monoamine oxidase B (MOAB) has been suggested to be involved in GGOH oxidation. Here, using two human hepatoma cell lines, we investigated whether MAOB contributes to GGA biosynthesis. Using either HuH-7 cell lysates or recombinant human MAOB, we found that: 1) the MAO inhibitor tranylcypromine dose-dependently downregulates endogenous GGA levels in HuH-7 cells; and 2) siRNA-mediated MAOB silencing reduces intracellular GGA levels in HuH-7 and Hep3B cells. Unexpectedly, however, CRISPR/Cas9-generated MAOB-KO human hepatoma Hep3B cells had GGA levels similar to those in MAOB-WT cells. A sensitivity of GGA levels to siRNA-mediated MAOB downregulation was recovered when the MAOB-KO cells were transfected with a MAOB-expression plasmid, suggesting that MAOB is the enzyme primarily responsible for GGOH oxidation and that some other latent metabolic pathways may maintain endogenous GGA levels in the MAOB-KO hepatoma cells. Along with the previous findings, these results provide critical insights into the biological roles of human MAOB and provide evidence that hepatic MAOB is involved in endogenous GGA biosynthesis via GGOH oxidation.

Many clinical studies and epidemiological investigations have clearly demonstrated that women are twice as likely to develop cholesterol gallstones as men, and oral contraceptives and other estrogen therapies dramatically increase that risk. Further, animal studies have revealed that estrogen promotes cholesterol gallstone formation through the estrogen receptor (ER) α, but not ERβ, pathway. More importantly, some genetic and pathophysiological studies have found that G protein-coupled estrogen receptor (GPER) 1 is a new gallstone gene, Lith18, on chromosome 5 in mice and produces additional lithogenic actions, working independently of ERα, to markedly increase cholelithogenesis in female mice. Based on computational modeling of GPER, a novel series of GPER-selective antagonists were designed, synthesized, and subsequently assessed for their therapeutic effects via calcium mobilization, cAMP, and ERα and ERβ fluorescence polarization binding assays. From this series of compounds, one new compound, 2-cyclohexyl-4-isopropyl-N-(4-methoxybenzyl)aniline (CIMBA), exhibits superior antagonism and selectivity exclusively for GPER. Furthermore, CIMBA reduces the formation of 17β-estradiol-induced gallstones in a dose-dependent manner in ovariectomized mice fed a lithogenic diet for 8 weeks. At 32 μg/day/kg CIMBA, no gallstones are found, even in ovariectomized ERα (^–/–) mice treated with 6 μg/day 17β-estradiol and fed the lithogenic diet for 8 weeks. In conclusion, CIMBA treatment protects against the formation of estrogen-induced cholesterol gallstones by inhibiting the GPER signaling pathway in female mice. CIMBA may thus be a new agent for effectively treating cholesterol gallstone disease in women.­

The formation and properties of liquid-ordered (Lo) lipid domains (rafts) in the plasma membrane are still poorly understood. This limits our ability to manipulate ordered lipid domain-dependent biological functions. Giant plasma membrane vesicles (GPMVs) undergo large-scale phase separations into coexisting Lo and liquid-disordered lipid domains. However, large-scale phase separation in GPMVs detected by light microscopy is observed only at low temperatures. Comparing Förster resonance energy transfer-detected versus light microscopy-detected domain formation, we found that nanodomains, domains of nanometer size, persist at temperatures up to 20°C higher than large-scale phases, up to physiologic temperature. The persistence of nanodomains at higher temperatures is consistent with previously reported theoretical calculations. To investigate the sensitivity of nanodomains to lipid composition, GPMVs were prepared from mammalian cells in which sterol, phospholipid, or sphingolipid composition in the plasma membrane outer leaflet had been altered by cyclodextrin-catalyzed lipid exchange. Lipid substitutions that stabilize or destabilize ordered domain formation in artificial lipid vesicles had a similar effect on the thermal stability of nanodomains and large-scale phase separation in GPMVs, with nanodomains persisting at higher temperatures than large-scale phases for a wide range of lipid compositions. This indicates that it is likely that plasma membrane nanodomains can form under physiologic conditions more readily than large-scale phase separation. We also conclude that membrane lipid substitutions carried out in intact cells are able to modulate the propensity of plasma membranes to form ordered domains. This implies lipid substitutions can be used to alter biological processes dependent upon ordered domains.

The autosomal dominant disorder Schnyder corneal dystrophy (SCD) is caused by mutations in UbiA prenyltransferase domain-containing protein-1 (UBIAD1), which uses geranylgeranyl pyrophosphate (GGpp) to synthesize the vitamin K₂ subtype menaquinone-4 (MK-4). SCD is characterized by opacification of the cornea, owing to aberrant build-up of cholesterol in the tissue. We previously discovered that sterols stimulate association of UBIAD1 with ER-localized HMG-CoA reductase, which catalyzes a rate-limiting step in the synthesis of cholesterol and nonsterol isoprenoids, including GGpp. Binding to UBIAD1 inhibits sterol-accelerated ER-associated degradation (ERAD) of reductase and permits continued synthesis of GGpp in cholesterol-replete cells. GGpp disrupts UBIAD1-reductase binding and thereby allows for maximal ERAD of reductase as well as ER-to-Golgi translocation of UBIAD1. SCD-associated UBIAD1 is refractory to GGpp-mediated dissociation from reductase and remains sequestered in the ER to inhibit ERAD. Here, we report development of a biochemical assay for UBIAD1-mediated synthesis of MK-4 in isolated membranes and intact cells. Using this assay, we compared enzymatic activity of WT UBIAD1 with that of SCD-associated variants. Our studies revealed that SCD-associated UBIAD1 exhibited reduced MK-4 synthetic activity, which may result from its reduced affinity for GGpp. Sequestration in the ER protects SCD-associated UBIAD1 from autophagy and allows intracellular accumulation of the mutant protein, which amplifies the inhibitory effect on reductase ERAD. These findings have important implications not only for the understanding of SCD etiology but also for the efficacy of cholesterol-lowering statin therapy, which becomes limited, in part, because of UBIAD1-mediated inhibition of reductase ERAD.

Adipocytes take up long chain FAs through diffusion and protein-mediated transport, whereas FA efflux is considered to occur by diffusion. To identify potential membrane proteins that are involved in regulating FA flux in adipocytes, the expression levels of 55 membrane transporters without known function were screened in subcutaneous adipose samples from obese patients before and after bariatric surgery using branched DNA methodology. Among the 33 solute carrier (SLC) transporter family members screened, the expression of 14 members showed significant changes before and after bariatric surgery. One of them, Slc43a3, increased about 2.5-fold after bariatric surgery. Further investigation demonstrated that Slc43a3 is highly expressed in murine adipose tissue and induced during adipocyte differentiation in primary preadipocytes and in OP9 cells. Knockdown of Slc43a3 with siRNA in differentiated OP9 adipocytes reduced both basal and forskolin-stimulated FA efflux, while also increasing FA uptake and lipid droplet accumulation. In contrast, overexpression of Slc43a3 decreased FA uptake in differentiated OP9 cells and resulted in decreased lipid droplet accumulation. Therefore, Slc43a3 seems to regulate FA flux in adipocytes, functioning as a positive regulator of FA efflux and as a negative regulator of FA uptake.

Acne is one of the most common dermatological conditions, but the details of its pathology are unclear, and current management regimens often have adverse effects. Cutibacterium acnes is known as a major acne-associated bacterium that derives energy from lipase-mediated sebum lipid degradation. C. acnes is commensal, but lipase activity has been observed to differ among C. acnes types. For example, higher populations of the type IA strains are present in acne lesions with higher lipase activity. In the present study, we examined a conserved lipase in types IB and II that was truncated in type IA C. acnes strains. Closed, blocked, and open structures of C. acnes ATCC11828 lipases were elucidated by X-ray crystallography at 1.6–2.4 Å. The closed crystal structure, which is the most common form in aqueous solution, revealed that a hydrophobic lid domain shields the active site. By comparing closed, blocked, and open structures, we found that the lid domain-opening mechanisms of C. acnes lipases (_CAlipases) involve the lid-opening residues, Phe-179 and Phe-211. To the best of our knowledge, this is the first structure-function study of _CAlipases, which may help to shed light on the mechanisms involved in acne development and may aid in future drug design.

Fatty liver involves ectopic lipid accumulation and dysregulated hepatic oxidative metabolism, which can progress to a state of elevated inflammation and fibrosis referred to as nonalcoholic steatohepatitis (NASH). The factors that control progression from simple steatosis to NASH are not fully known. Here, we tested the hypothesis that dietary vitamin E (VitE) supplementation would prevent NASH progression and associated metabolic alterations induced by a Western diet (WD). Hyperphagic melanocortin-4 receptor-deficient (MC4R^–/–) mice were fed chow, chow+VitE, WD, or WD+VitE starting at 8 or 20 weeks of age. All groups exhibited extensive hepatic steatosis by the end of the study (28 weeks of age). WD feeding exacerbated liver disease severity without inducing proportional changes in liver triglycerides. Eight weeks of WD accelerated liver pyruvate cycling, and 20 weeks of WD extensively upregulated liver glucose and oxidative metabolism assessed by ²H/¹³C flux analysis. VitE supplementation failed to reduce the histological features of NASH. Rather, WD+VitE increased the abundance and saturation of liver ceramides and accelerated metabolic flux dysregulation compared with 8 weeks of WD alone. In summary, VitE did not limit NASH pathogenesis in genetically obese mice, but instead increased some indicators of metabolic dysfunction.

The pregnane X receptor (PXR) is a nuclear receptor that can be activated by numerous drugs and xenobiotic chemicals. PXR thereby functions as a xenobiotic sensor to coordinately regulate host responses to xenobiotics by transcriptionally regulating many genes involved in xenobiotic metabolism. We have previously reported that PXR has pro-atherogenic effects in animal models, but how PXR contributes to atherosclerosis development in different tissues or cell types remains elusive. In this study, we generated an LDL receptor-deficient mouse model with myeloid-specific PXR deficiency (PXR^MyeLDLR^–/–) to elucidate the role of macrophage PXR signaling in atherogenesis. The myeloid PXR deficiency did not affect metabolic phenotypes and plasma lipid profiles, but PXR^MyeLDLR^–/– mice had significantly decreased atherosclerosis at both aortic root and brachiocephalic arteries compared with control littermates. Interestingly, the PXR deletion did not affect macrophage adhesion and migration properties, but reduced lipid accumulation and foam cell formation in the macrophages. PXR deficiency also led to decreased expression of the scavenger receptor CD36 and impaired lipid uptake in macrophages of the PXR^MyeLDLR^–/– mice. Further, RNA-Seq analysis indicated that treatment with a prototypical PXR ligand affects the expression of many atherosclerosis-related genes in macrophages in vitro. These findings reveal a pivotal role of myeloid PXR signaling in atherosclerosis development and suggest that PXR may be a potential therapeutic target in atherosclerosis management.

Cellular membranes are not homogenous mixtures of proteins; rather, they are segregated into microdomains on the basis of preferential association between specific lipids and proteins. These microdomains, called lipid rafts, are well known for their role in receptor signaling on the plasma membrane (PM) and are essential to such cellular functions as signal transduction and spatial organization of the PM. A number of disease states, including atherosclerosis and other cardiovascular disorders, may be caused by dysfunctional maintenance of lipid rafts. Lipid rafts do not occur only in the PM but also have been found in intracellular membranes and extracellular vesicles (EVs). Here, we focus on discussing newly discovered functions of lipid rafts and microdomains in intracellular membranes, including lipid and protein trafficking from the ER, Golgi bodies, and endosomes to the PM, and we examine lipid raft involvement in the production and composition of EVs. Because lipid rafts are small and transient, visualization remains challenging. Future work with advanced techniques will continue to expand our knowledge about the roles of lipid rafts in cellular functioning.

Lipid rafts are highly ordered regions of the plasma membrane that are enriched in cholesterol and sphingolipids and play important roles in many cells. In hematopoietic stem and progenitor cells (HSPCs), lipid rafts house receptors critical for normal hematopoiesis. Lipid rafts also can bind and sequester kinases that induce negative feedback pathways to limit proliferative cytokine receptor cycling back to the cell membrane. Modulation of lipid rafts occurs through an array of mechanisms, with optimal cholesterol efflux one of the major regulators. As such, cholesterol homeostasis also regulates hematopoiesis. Increased lipid raft content, which occurs in response to changes in cholesterol efflux in the membrane, can result in prolonged receptor occupancy in the cell membrane and enhanced signaling. In addition, certain diseases, like diabetes, may contribute to lipid raft formation and affect cholesterol retention in rafts. In this review, we explore the role of lipid raft-related mechanisms in hematopoiesis and CVD (specifically, atherosclerosis) and discuss how defective cholesterol efflux pathways in HSPCs contribute to expansion of lipid rafts, thereby promoting myelopoiesis and thrombopoiesis. We also discuss the utility of cholesterol acceptors in contributing to lipid raft regulation and disruption, and highlight the potential to manipulate these pathways for therapeutic gain in CVD as well as other disorders with aberrant hematopoiesis.