Bringing structural competency to the forefront of dental education.

Cultural competency as introduced to the healthcare industry had the intention to alleviate and familiarize all healthcare providers with individuals of other cultures and backgrounds than "self". It attempted to fill in the gaps and prepare providers to relate better with their patients and provide cross-cultural care. Although it gave the impression of helping to decrease biases and stigma, it resulted in stronger biases, stereotypes of different ethnic groups, and racial profiling. It never acknowledged the systemic barriers that are so ingrained in our society that determine who gets access to care, and who gets the best outcomes in our healthcare system. Starting with the premise of our Surgeon General Reports, we reviewed the Social Determinants of Health and the relationship to structural barriers. This manuscript describes the numerous barriers that affect the access to care, and outcomes of the most marginalized population in the US. Numerous of which are so prevalent amongst all of us that they "feel normal" that there is a degree of structural blindness. We share the experience and frameworks to assess the structural vulnerability of our patients and introduce the different aspects of the curriculum and research that are currently in place to address and bring structural competency to the forefront of dental education at WesternU College of Dental Medicine in Pomona CA.

Brain-derived neurotrophic factor overexpression in taste buds diminishes chemotherapy induced taste loss.

Vismodegib is used in patients suffering from advanced basal cell carcinoma (BCC), but 100% of the patients taking it report dysgeusia and 50% discontinue the treatment. Treatment with neurotrophic factors can stimulate neuronal survival and functional improvement in injured organs. Here, we analysed novel transgenic mouse lines in which brain-derived neurotrophic factor (BDNF) is overexpressed in taste buds, to examine whether higher levels of BDNF would reduce or prevent negative side effects of vismodegib in the taste system. BDNF plays crucial roles for development, target innervation, and survival of gustatory neurons and taste buds. The behavioural test in this study showed that vehicle-treated wild-type mice prefered 10 mM sucrose over water, whereas vismodegib treatment in wild-type mice caused total taste loss. Gustducin-BDNF mice had a significantly increased preference for low concentration of sucrose solution over water compared to wild-type mice, and most importantly the transgenic mice were able to detect low concentrations of sucrose following vismodegib treatment. We evaluated taste cell morphology, identity, innervation and proliferation using immunohistochemistry. All drug-treated mice exhibited deficits, but because of a possible functional upcycled priming of the peripheral gustatory system, GB mice demonstrated better morphological preservation of the peripheral gustatory system. Our study indicates that overexpression of BDNF in taste buds plays a role in preventing degeneration of taste buds. Counteracting the negative side effects of vismodegib treatment might improve compliance and achieve better outcome in patients suffering from advanced BCC.

Periodontitis and diabetes mellitus co-morbidity: A molecular dialogue.

BACKGROUND: Type 2 diabetes mellitus (T2DM) and periodontitis are two biologically linked diseases that often coexist in complex interaction. While periodontitis may lead to insulin receptor desensitization, diabetes may increase the expression of inflammatory cytokines, such as Tumor Necrosis Factor-α (TNF-α) and Interleukin 6 (IL-6), in the gingival crevicular fluid and activate osteoclasts via Receptor activator of nuclear factor kappa-Β ligand (RANK-L) production, leading to bone resorption. However, the association between the two diseases processes, where one may exacerbate the progression of the other, is unclear. In addition, both diseases have similar mechanistic themes, such as chronic inflammation and oxidative stress. This review aimed to investigate the pathophysiological and molecular mechanisms underlying T2DM and periodontitis. HIGHLIGHT: Uncontrolled diabetes is often associated with severe periodontitis, measured by clinical attachment loss. Alteration in the oral microbiome composition, which may activate the host inflammatory response and lead to irreversible oxidative stress, is a common finding in both diseases. An understanding of the molecular crosstalk between the two disease processes is crucial for developing therapeutic targets that inhibit bone resorption and halt the progression of periodontitis in patients with diabetes. CONCLUSION: The Oral microbiome composition in T2DM and periodontitis shifts toward dysbiosis, favoring bacterial pathogens, such as Fusobacteria and Porphyromonas species. Both conditions are marked by pro-inflammatory immune activity via the activation of Interleukin 17 (IL-17), Interleukin 1 (IL-1), TNF-α, and Nuclear Factor Kappa Beta (NF-κB). Common molecular crosstalk signaling appears to involve advanced glycation end products (AGEs) and oxidative stress. Thus, future drug targets are multifactorial, ranging from modulatory of host inflammatory response to preventing the accumulation of AGEs and oxidative free radicals.

Demystifying the Institutional Review Board.

Perioperative nurses are responsible for generating and using evidence to improve patient care. To protect human participants during research activities, government regulations enacted after widely publicized research misconduct specify that institutions receiving federal funds must have an institutional review board (IRB) comprising at least five members. Board members have many responsibilities, including completing a thorough review of each section of the application and attachments (eg, consent documents). To expedite the IRB approval processes, applicants should create and submit a well-written application. Applicants should understand that the application addresses the important ethical concepts of respect for persons, beneficence, and justice. Quality improvement activities (ie, local activities that seek to improve patient care or clinical outcomes) differ from research activities that focus on creating new knowledge. Depending on the purpose, design, and generalizability of a quality improvement project, the applicant may need to submit the project to the IRB for approval.

A preclinical hybrid curriculum and its impact on dental student learning outcomes.

OBJECTIVES: The purpose of this study is to measure how the implementation of an online, preclinical hybrid curriculum impacts dental student clinic readiness, the outcomes of grades, critical thinking skills, and student and faculty perceptions respectively. METHODS: This longitudinal comparative and descriptive study used objective data and subjective (survey) data for 4 dental class cohorts. Groups A and B experienced a traditional lecture-based curriculum, while Groups C and D experienced a hybrid curriculum that was lecture-free and implemented active learning. The Health Sciences Reasoning Test (HSRT), an objective assessment, was used to measure students' critical thinking skills. RESULTS: Dental student outcomes have either remained steady or improved with the transition to a new hybrid curriculum. According to the student and faculty survey results, the hybrid curriculum promoted student learning, independence, critical thinking, initiative and self-motivation, and clinic practice readiness. Group C (N = 68) Total Online Platform mean scores demonstrated a significant and moderately strong correlation with the preclinical course mean grades (r = 0.68, P = 0.00). Group D HSRT (n = 63) for Attempt 1 (end of year 1) and Attempt 2 (end of Year 2) paired T test resulted in HSRT Overall (mean difference = -2.27, SD = 7.21, t = -2.5, P = 0.02) for the second preclinical year. CONCLUSION: The hybrid curricular approach afforded many benefits. Faculty took an active role in imparting knowledge when compared to the lecture hall. Having students immersed in continual assessment through an online adaptive platform and active learning promoted self-motivation, deeper learning, applied knowledge, and discouraged superficial memorization.

Assessing Patient Experience and Healthcare Quality of Dental Care Using Patient Online Reviews in the United States: Mixed Methods Study.

BACKGROUND: Over the last two decades, patient review websites have emerged as an essential online platform for doctor ratings and reviews. Recent studies suggested the significance of such websites as a data source for patients to choose doctors for healthcare providers to learn and improve from patient feedback and to foster a culture of trust and transparency between patients and healthcare providers. However, as compared to other medical specialties, studies of online patient reviews that focus on dentists in the United States remain absent. OBJECTIVE: This study sought to understand to what extent online patient reviews can provide performance feedbacks that reflect dental care quality and patient experience. METHODS: Using mixed informatics methods incorporating statistics, natural language processing, and domain expert evaluation, we analyzed the online patient reviews of 204,751 dentists extracted from HealthGrades with two specific aims. First, we examined the associations between patient ratings and a variety of dentist characteristics. Second, we identified topics from patient reviews that can be mapped to the national assessment of dental patient experience measured by the Patient Experience Measures from the Consumer Assessment of Healthcare Providers and Systems (CAHPS) Dental Plan Survey. RESULTS: Higher ratings were associated with female dentists (t71881=2.45, P<.01, g=0.01), dentists at a younger age (F7, 107128=246.97, P<.001, g=0.11), and those whose patients experienced a short wait time (F4, 150055=10417.77, P<0.001, g=0.18). We also identified several topics that corresponded to CAHPS measures, including discomfort (eg, painful/painless root canal or deep cleaning), and ethics (eg, high-pressure sales, and unnecessary dental work). CONCLUSIONS: These findings suggest that online patient reviews could be used as a data source for understanding the patient experience and healthcare quality in dentistry.

Rosmarinic Acid/ Blue Light Combination Treatment Inhibits Head and Neck Squamous Cell Carcinoma In Vitro.

BACKGROUND/AIM: This study investigated a novel combined therapy of rosmarinic acid (RA)/blue light on head and neck squamous cell carcinoma (HNSCC) cell proliferation in vitro. MATERIALS AND METHODS: HNSCC cells were exposed to BL (500 mW/cm2) for 90 s, and incubated with 80 µg/ml RA for 1 hour. Cell viability was determined after 24 h using WST-1 assay. Western blot was used to detect treatment-induced changes in epidermal growth factor receptor (EGFR) activation. Hydrogen peroxide (H2O2) and nitric oxide levels were quantified using CM-H2DCFH-DA assays. Apoptosis was assessed using Annexin V/PI staining and flow cytometry. RESULTS: RA/blue light treatment resulted in a significant reduction in cell viability, EGFR activation and H2O2 levels in all HNSCC cell lines. However, no significant changes in NO production or apoptosis induction were found. CONCLUSION: RA/blue light effectively decreased HNSCC cell proliferation through reduction in EGFR activation and H2O2 production, and not via induction of apoptosis.

RhoC mediates epidermal growth factor-stimulated migration and invasion in head and neck squamous cell carcinoma.

Epidermal growth factor receptor (EGFR) is overexpressed in head and neck squamous cell carcinoma (HNSCC) where it has been shown to promote tumor cell invasion upon phosphorylation. One mechanism by which EGFR promotes tumor progression is by activating signal cascades that lead to loss of E-cadherin, a transmembrane glycoprotein of the cell-cell adherence junctions; however mediators of these signaling cascades are not fully understood. One such mediator, RhoC, is activated upon a number of external stimuli, such as epidermal growth factor (EGF), but its role as a mediator of EGF-stimulated migration and invasion has not been elucidated in HNSCC. In the present study, we investigate the role of RhoC as a mediator of EGF-stimulated migration and invasion in HNSCC. We show that upon EGF stimulation, EGFR and RhoC were strongly activated in HNSCC. This resulted in activation of the phosphatidylinositol 3-Kinase Akt pathway (PI3K-Akt), phosphorylation of GSK-3ß at the Ser(9) residue, and subsequent down regulation of E-cadherin cell surface expression resulting in increased tumor cell invasion. Knockdown of RhoC restored E-cadherin expression and inhibited EGF-stimulated migration and invasion. This is the first report in HNSCC demonstrating the role RhoC plays in mediating EGF-stimulated migration and invasion by down-regulating the PI3K-Akt pathway and E-cadherin expression. RhoC may serve as a treatment target for HNSCC.

Prevalidation of salivary biomarkers for oral cancer detection.

BACKGROUND: Oral cancer is the sixth most common cancer with a 5-year survival rate of approximately 60%. Presently, there are no scientifically credible early detection techniques beyond conventional clinical oral examination. The goal of this study is to validate whether the seven mRNAs and three proteins previously reported as biomarkers are capable of discriminating patients with oral squamous cell carcinomas (OSCC) from healthy subjects in independent cohorts and by a National Cancer Institute (NCI)-Early Detection Research Network (EDRN)-Biomarker Reference Laboratory (BRL). METHODS: Three hundred and ninety-five subjects from five independent cohorts based on case controlled design were investigated by two independent laboratories, University of California, Los Angeles (Los Angeles, CA) discovery laboratory and NCI-EDRN-BRL. RESULTS: Expression of all seven mRNA and three protein markers was increased in OSCC versus controls in all five cohorts. With respect to individual marker performance across the five cohorts, the increase in interleukin (IL)-8 and subcutaneous adipose tissue (SAT) was statistically significant and they remained top performers across different cohorts in terms of sensitivity and specificity. A previously identified multiple marker model showed an area under the receiver operating characteristic (ROC) curve for prediction of OSCC status ranging from 0.74 to 0.86 across the cohorts. CONCLUSIONS: The validation of these biomarkers showed their feasibility in the discrimination of OSCCs from healthy controls. Established assay technologies are robust enough to perform independently. Individual cutoff values for each of these markers and for the combined predictive model need to be further defined in large clinical studies. IMPACT: Salivary proteomic and transcriptomic biomarkers can discriminate oral cancer from control subjects.

Rap1 mediates galanin receptor 2-induced proliferation and survival in squamous cell carcinoma.

Previously we showed that galanin, a neuropeptide, is secreted by human squamous cell carcinoma of the head and neck (SCCHN) in which it exhibits an autocrine mitogenic effect. We also showed that rap1, a ras-like signaling protein, is a critical mediator of SCCHN progression. Given the emerging importance of the galanin cascade in regulating proliferation and survival, we investigated the effect of GAL on SCCHN progression via induction of galanin receptor 2 (GALR2)-mediated rap1 activation. Studies were performed in multiple SCCHN cell lines by inducing endogenous GALR2, by stably overexpressing GALR2 and by downregulating endogenous GALR2 with siGALR2. Cell proliferation and survival, mediated by the ERK and AKT signaling cascades, respectively, were evaluated by functional and immunoblot analysis. The role of rap1 in GALR2-mediated proliferation and survival was evaluated by modulating expression. Finally, the effect of GALR2 on tumor growth was determined. GALR2 stimulated proliferation and survival via ERK and AKT activation, respectively. Knockdown or inactivation of rap1 inhibited GALR2-induced, AKT and ERK-mediated survival and proliferation. Overexpression of GALR2 promoted tumor growth in vivo. GALR2 promotes proliferation and survival in vitro, and promotes tumor growth in vivo, consistent with an oncogenic role for GALR2 in SCCHN.

Collection, storage, and processing of saliva samples for downstream molecular applications.

Saliva is an ideal translational research tool and diagnostic medium and is being used in novel ways to provide molecular biomarkers for a variety of oral and systemic diseases and conditions. The ability to analyze saliva to monitor health and disease is a highly desirable goal for oral health promotion and research. Saliva has been used to detect caries risk, periodontitis, oral cancer, breast cancer, salivary gland diseases, and systemic disorders such as hepatitis, HIV and HCV. Technology advancement has allowed high-throughput studies to be performed at a scale unrealized previously and is serving to advance the discovery and validation of salivary disease biomarkers. Of course, successful measurement of salivary analytes requires optimal collection, processing, and storage procedures and conditions. This chapter describes protocols for saliva collection, processing, and storage for the molecular analysis of salivary diagnostic constituents.

Rap1 stabilizes beta-catenin and enhances beta-catenin-dependent transcription and invasion in squamous cell carcinoma of the head and neck.

PURPOSE: In head and neck squamous cell carcinoma (HNSCC) cells, Rap1 shuttles between the nucleus and cytoplasm. Prior findings suggested that Rap1 may modulate the beta-catenin-independent Wnt pathway in some settings, but the role of Rap1 in beta-catenin-dependent Wnt signaling remains undefined. EXPERIMENTAL DESIGN AND RESULTS: We observed that beta-catenin bound to active Rap1 in vitro and Rap1 activated beta-catenin/T-cell factor (TCF)-dependent transcription. Immunofluorescence studies showed that ectopic expression of Rap1 increased nuclear translocation of beta-catenin. Overexpression of active Rap1 facilitated an increase in beta-catenin-mediated transcription that was abrogated by dominant-negative TCF4. Conversely, small interfering RNA-mediated inhibition of endogenous Rap1 expression inhibited beta-catenin/TCF-mediated transcription as well as invasion of HNSCC. Furthermore, inhibition of Rap1 expression downregulated the expression of matrix metalloproteinase 7, a transcriptional target of beta-catenin/TCF. In HNSCC cells stably transfected with beta-catenin or treated with lithium chloride or Wnt3A to stabilize endogenous beta-catenin, inhibition of Rap1 expression led to decreases in the free pool of beta-catenin. Immunohistochemical studies of tissue from HNSCC patients revealed that increased beta-catenin intensity correlated with higher tumor stage. Furthermore, the prognostic effect of active Rap1 on tumor N stage was found to depend on cytosolic beta-catenin expression (P < 0.013). When beta-catenin is high, higher Rap1GTP intensity is associated with more advanced N stage. CONCLUSIONS: The findings suggest that Rap1 enhances beta-catenin stability and nuclear localization. In addition to indicating that Rap1 has a significant role in regulating beta-catenin and beta-catenin-dependent progression to more advanced N-stage lesions, these data highlight Rap1 as a potential therapeutic target in HNSCC.

Salivary microRNA: discovery, characterization, and clinical utility for oral cancer detection.

PURPOSE: We have previously shown that a transcriptome is found in saliva and subpanels of these mRNAs can be used as oral cancer biomarkers. In this study, we measured the presence of microRNAs (miRNA) in saliva and determined their potential as an additional set of oral cancer biomarkers. EXPERIMENTAL DESIGN: A total of 314 miRNAs were measured using reverse transcriptase-preamplification-quantitative PCR in 12 healthy controls. Degradation pattern of endogenous and exogenous saliva miRNAs were measured at room temperature over time. Selected miRNAs were validated in saliva of 50 oral squamous cell carcinoma patients and 50 healthy matched control subjects. RESULTS: We detected approximately 50 miRNAs in both the whole and supernatant saliva. Endogenous saliva miRNA degraded much slower compared with exogenous miRNA. Two miRNAs, miR-125a and miR-200a, were present in significantly lower levels (P < 0.05) in the saliva of oral squamous cell carcinoma patients than in control subjects. CONCLUSIONS: Both whole and supernatant saliva of healthy controls contained dozens of miRNAs, and similar to saliva mRNAs, these miRNAs are stable. Saliva miRNAs can be used for oral cancer detection.

Fungiform papilla pattern: EGF regulates inter-papilla lingual epithelium and decreases papilla number by means of PI3K/Akt, MEK/ERK, and p38 MAPK signaling.

Fungiform papillae are epithelial taste organs that form on the tongue, requiring differentiation of papillae and inter-papilla epithelium. We tested roles of epidermal growth factor (EGF) and the receptor EGFR in papilla development. Developmentally, EGF was localized within and between papillae whereas EGFR was progressively restricted to inter-papilla epithelium. In tongue cultures, EGF decreased papillae and increased cell proliferation in inter-papilla epithelium in a concentration-dependent manner, whereas EGFR inhibitor increased and fused papillae. EGF preincubation could over-ride disruption of Shh signaling that ordinarily would effect a doubling of fungiform papillae. With EGF-induced activation of EGFR, we demonstrated phosphorylation in PI3K/Akt, MEK/ERK, and p38 MAPK pathways; with pathway inhibitors (LY294002, U0126, SB203580) the EGF-mediated decrease in papillae was reversed, and synergistic actions were shown. Thus, EGF/EGFR signaling by means of PI3K/Akt, MEK/ERK, and p38 MAPK contributes to epithelial cell proliferation between papillae; this biases against papilla differentiation and reduces numbers of papillae.

The proteomes of human parotid and submandibular/sublingual gland salivas collected as the ductal secretions.

Saliva is a body fluid with important functions in oral and general health. A consortium of three research groups catalogued the proteins in human saliva collected as the ductal secretions: 1166 identifications--914 in parotid and 917 in submandibular/sublingual saliva--were made. The results showed that a high proportion of proteins that are found in plasma and/or tears are also present in saliva along with unique components. The proteins identified are involved in numerous molecular processes ranging from structural functions to enzymatic/catalytic activities. As expected, the majority mapped to the extracellular and secretory compartments. An immunoblot approach was used to validate the presence in saliva of a subset of the proteins identified by mass spectrometric approaches. These experiments focused on novel constituents and proteins for which the peptide evidence was relatively weak. Ultimately, information derived from the work reported here and related published studies can be used to translate blood-based clinical laboratory tests into a format that utilizes saliva. Additionally, a catalogue of the salivary proteome of healthy individuals allows future analyses of salivary samples from individuals with oral and systemic diseases, with the goal of identifying biomarkers with diagnostic and/or prognostic value for these conditions; another possibility is the discovery of therapeutic targets.

Exon-level expression profiling: a comprehensive transcriptome analysis of oral fluids.

BACKGROUND: The application of global gene expression profiling to saliva samples is hampered by the presence of partially fragmented and degraded RNAs that are difficult to amplify and detect with the prevailing technologies. Moreover, the often limited volume of saliva samples is a challenge to quantitative PCR (qPCR) validation of multiple candidates. The aim of this study was to provide proof-of-concept data on the combination of a universal mRNA-amplification method with exon arrays for candidate selection and a multiplex preamplification method for easy validation. METHODS: We used a universal mRNA-specific linear-amplification strategy in combination with Affymetrix Exon Arrays to amplify salivary RNA from 18 healthy individuals on the nanogram scale. Multiple selected candidates were preamplified in one multiplex reverse transcription PCR reaction, cleaned up enzymatically, and validated by qPCR. RESULTS: We defined a salivary exon core transcriptome (SECT) containing 851 transcripts of genes that have highly similar expression profiles in healthy individuals. A subset of the SECT transcripts was verified by qPCR analysis. Informatics analysis of the SECT revealed several functional clusters and sequence motifs. Sex-specific salivary exon biomarkers were identified and validated in tests with samples from healthy individuals. CONCLUSIONS: It is feasible to use samples containing fragmented RNAs to conduct high-resolution expression profiling with coverage of the entire transcriptome and to validate multiple targets from limited amounts of sample.

Targeting apoptosis to overcome cisplatin resistance: a translational study in head and neck cancer.

PURPOSE: Cisplatin resistance remains a barrier to organ-sparing and survival of patients with advanced head and neck squamous cell carcinoma (HNSCC). Targeted therapies to overcome cisplatin-resistant HNSCC are being developed. METHODS AND MATERIALS: Cisplatin-sensitive parental HNSCC cell lines and cisplatin-resistant progeny were studied. Pretreatment HNSCC biopsies were used to construct tissue microarrays which were stained for p53 and Bcl-xL. RESULTS: HNSCC cell lines selected for cisplatin resistance had wild-type p53 and high levels of Bcl-xL. Expression of wild-type p53 in cell lines with low Bcl-xL enhanced cisplatin sensitivity. Expression of both Bcl-xL and wild-type p53 caused tumor cells to become cisplatin resistant. Patients whose tumors expressed low levels of p53 and Bcl-xL enjoyed the best organ preservation and disease-free survival whereas patients whose tumors expressed low levels of p53 and high levels of Bcl-xL had the worst outcome. Novel agents that inhibit Bcl-xL or activate p53 function may target cisplatin-resistant HNSCC. CONCLUSION: Cisplatin resistance in HNSCC is mediated, at least in part, by high Bcl-xL and functional p53.

(-)-gossypol inhibits growth and promotes apoptosis of human head and neck squamous cell carcinoma in vivo.

Resistance to chemotherapy is a common problem encountered in the treatment of head and neck squamous cell carcinoma (HNSCC). Chemoresistant HNSCC tumors frequently overexpress antiapoptotic proteins, such as Bcl-x(L). (-)-gossypol, the negative enantiomer of a cottonseed polyphenol, binds to Bcl-x(L) and was recently been shown to inhibit HNSCC proliferation in vitro. In this study, we assessed the in vivo efficacy of (-)-gossypol in an orthotopic xenograft model of HNSCC, using two human HNSCC cell lines with high Bcl-x(L) expression levels. Both produced tumors in a murine floor-of-mouth model that mimics human HNSCC, exhibiting growth and invasion into adjacent tissues. Mice were randomized into three groups: vehicle control and two daily intraperitoneal (-)-gossypol treatment groups (5 and 15 mg/kg). Tumors were measured twice weekly. In the control group, tumors grew progressively, whereas in (-)-gossypol treatment groups, tumor growth was significantly suppressed. The mitotic rate in tumors from (-)-gossypol-treated animals was significantly lower than that in controls, and an increase in the percentage of apoptotic cells was observed in treated tumors versus controls. Residual tumors remained growth-suppressed for 2 weeks after cessation of (-)-gossypol treatment. Our results demonstrate that (-)-gossypol can inhibit tumor growth in an orthotopic model of aggressive HNSCC.