A Comparison of Collaborative Practice and Teacher Leadership Between Low-Performing and High-Performing Rural Kentucky High Schools

This article reports the findings of the 2011 results of ‘very rural’ Kentucky high schools on the Teaching, Empowering, Leading and Learning (TELL) Survey to determine whether differences existed between high and low performing rural schools across specific survey items. Schools with ACT scores one standard deviation (or more) above their predicted value were compared to rural high schools where students’ ACT scores were one standard deviation (or more) below their predicted value. Beale Codes of seven through nine from the United States Department of Agriculture were used to identify very rural Kentucky high schools. Very rural high schools identified as high-performing demonstrated significantly different results on survey items related to a culture of collaboration and teacher leadership than rural high schools identified as low performing. The survey suggested that in high-performing schools, the principal and teachers supported each other in their development as instructional leaders, and established communication and collaboration skills with families and community stakeholders

The effects of mitoquinone pretreatment on doxorubicin-induced acute cardiac dysfunction

Introduction: Doxorubicin (DOX) is a widely used anti-cancer drug notorious for its irreversible cardiac toxicity. Currently, Dexrazoxane is the only FDA-approved treatment for this toxicity. However, Dexrazoxane still bears some serious adverse events, and developing new strategies to mitigate DOX-induced heart damage is critical. Our lab has shown that pretreatment of the H9c2 myoblast cells with mitoquinone (MitoQ), a mitochondrial-targeted antioxidant, and significantly improved cells’ resiliency to DOX. This study aimed to determine if MitoQ pretreatment can preserve cardiac function against DOX-induced damage in isolated rat hearts. Objectives: The effects of DOX and MitoQ on cardiac function were evaluated in isolated rat hearts. Moreover, the benefits of MitoQ pretreatment on DOX-induced cardiac dysfunction were also assessed. Methods: Langendorff heart preparation was performed after anesthesia of male SD rats (275-325 g). Hearts were isolated and retrograde perfused with Krebs’ buffer at a constant pressure of 80 mmHg with 37 ⁰C and pH of 7.35-7.45. Cardiac parameters, including left ventricle end-systolic pressure (LVESP), left ventricle end-diastolic pressure (LVEDP), left ventricular developed pressure (LVDP=LVESP-LVEDP), maximal rate of rise of LVP (dP/dt(max)), and heart rate (HR), were measured by a pressure transducer placed in the left ventricle of the rat heart. After obtaining a stable initial cardiac function, DOX (20 µM or 25 µM) or MitoQ (0.1-0.5 or 1-2.5 µM) were infused into the heart for 60 min. to determine the individual drug\u27s effects on the cardiac function. Moreover, another set of hearts was pretreated with MitoQ (0.25-0.5 or 1-2.5 µM) for 10-15 min before giving DOX (25 µM) to evaluate if MitoQ pretreatment would mitigate DOX-induced cardiac dysfunction. Cardiac functions were recorded every 5 min. throughout the experiments. The ratio between the final and initial recordings was calculated and compared among experimental groups. Results: Acute infusion of DOX into the isolated hearts dose-dependently reduced some cardiac parameters. Higher dose DOX (25 μM, n=5) induced a higher reduction in the ratios of LVESP, LVDP, and dP/dt(max) to 0.39±0.05, 0.35±0.06, and 0.26±0.05 than those of lower dose DOX infusion (20 μM, n=2; 0.77±0.01, 0.75±0.01, and 0.57±0.01), respectively. DOX had no effects on LVEDP and HR. Moreover, lower doses of MitoQ (0.1-0.5 μM, n=6) only slightly reduced HR to 0.77±0.01 without affecting other parameters. By contrast, higher doses of MitoQ (1-5 μM, n=4) reduced the ratios of LVESP, LVDP, dP/dt(max), and HR to 0.72±0.12, 0.51±0.18, and 0.45±0.17 0.65±0.07, respectively. Interestingly, MitoQ pretreatment before DOX (25 µM) exhibited better cardiac function accompanied by reduced HR than DOX alone. Higher MitoQ (1-2.5 µM) pretreatment improved the ratios of cardiac LVESP, LVDP, and dP/dt(max) to 0.67±0.14, 0.65±0.16, and 0.40±0.09, which were higher than those of lower dose MitoQ (0.25-0.5 μM, n=3; 0.49±0.11, 0.44±0.11, and 0.36±0.08), respectively. Conclusion: The preliminary data suggest that infusion of DOX into the heart acutely attenuated cardiac systolic function. Higher doses of MitoQ, not lower doses, also suppressed cardiac function. MitoQ pretreatment mitigated DOX-induced heart dysfunction. Acknowledgement: The project is funded by CCDA at PCOM

The effects of Mitoquinone on simulated ischemia/reperfusion injuries in H9c2 cells

Introduction: Reperfusion to an ischemic myocardium could result in damage termed myocardial ischemia/reperfusion (I/R) injury. Mitochondrial dysfunction is a major factor in I/R injury, producing less ATP and generating more reactive oxygen species (ROS). Mitoquinone (MitoQ) is an antioxidant that highly accumulates in the mitochondria. However, the dose-response effects and underlying mechanisms of MitoQ on simulated I/R injury have not been well established. Objectives: We hypothesized that H9c2 myoblast cells would be damaged by simulated I/R. Moreover, MitoQ would attenuate myocardial injury, characterized by increased cell viability, compared to non-treated control. Methods: The H9c2 myoblast cells (less than 20 passages) were treated with or without various concentrations of MitoQ (0.005, 0.05, 0.1, 0.5, 1, 2, 5 μM) under 3 different mediums: normal (containing 4.5 g glucose and pyruvate), low glucose (containing 1 g glucose and pyruvate), and no glucose/pyruvate medium. Three different experiments were conducted on the cells. The first experiment aimed to determine if MitoQ alone exerts different effects under different medium conditions by treating the cells with MitoQ for 24 hrs in a normal incubator. The second experiment aimed to determine if MitoQ increased cell viability under simulated ischemia conditions after MitoQ pretreatment. The third experiment aimed to determine if MitoQ increased cell viability under simulated I/R conditions after MitoQ pretreatment. Cell viability was measured by absorbance at 450 nm after adding a cell counting agent. The change in cell viability was expressed as ratios relative to the untreated controls. Results: Low concentrations of MitoQ alone slightly increased cell viability in all three mediums. The maximum increased cell viability was 1.25 ± 0.07 (n=9) at 0.005 μM MitoQ in the normal medium, 1.35 ± 0.23 (n=5, p MitoQ pretreatment exerts protection to cells in simulated ischemia conditions at certain MitoQ concentrations. The maximum increased cell viability was 1.37 ± 0.3 (n=4) at 0.01 μM MitoQ in normal medium, 1.20 ± 0.13 (n=4) at 1.0 μM MitoQ in low glucose medium, and 1.45 ± 0.24 (n=3) at 0.1 μM MitoQ in no glucose medium compared to the untreated control. MitoQ effects on simulated I/R injury will be reported in the future. Discussion: Preliminary data shows the effects of MitoQ alone and MitoQ pretreatment in ischemic conditions on cell viability is influenced by different mediums and concentrations of MitoQ

Comparison of the inhibition of an OCT3 transporter inhibitor, Nilotinib, on Doxorubicin’s effects on cardiac and cancer cell lines

Introduction Doxorubicin (DOX)-induced cardiotoxicity remains a significant barrier limiting its clinical application due to a lack of effective resolution. Targeting how DOX enters cardiac and cancer cells is a promising new strategy. Research suggests that an OCT3 transporter significantly contributes to DOX entry into the heart tissue. By contrast, it expresses much lower on breast cancer cell lines. Moreover, Nilotinib (NIB) can suppress OCT3 transporter function by 80%. Therefore, exploring the impact of NIB on the DOX’s effects on cardiac and cancer cell lines by altering DOX intracellular accumulation is intriguing. Objective First, we would establish a dose-response curve of DOX and NIB alone to assess their individual effects on cell viability. Secondly, we would record the impact of NIB on DOX entry within cardiac myoblasts (H9C2) and breast cancer cells (MCF7) through OCT3 transporter antagonism to assess if NIB can exert cardioprotective effects while maintaining DOX’s anticancer effect. Methods H9C2 myoblast and MCF7 breast cancer cells were seeded in 96-well black plates. Cells were treated with only DOX or NIB to establish a dose-response curve. Moreover, NIB was combined with DOX as a cotreatment or pretreatment regimen to evaluate the impacts of NIB on DOX’s effect. Titrated combinations of NIB (10 nM, 50 nM, 100 nM, 500 nM, 1 µM, 2 µM, 5 µM) and DOX (10 µM and 40µM) were used. Bioassays were conducted after cells were treated for 24 hours. Intracellular DOX fluorescence intensity was measured at 488/590 nm by fluoroskan. Subsequently, cell viability was detected by measuring absorbance at 450 nm after adding a cell counting reagent. The data were expressed as a ratio relative to untreated or the DOX control. Results DOX dose-dependently reduced viability of H9c2 and MCF7 cells. H9c2 cell showed significantly lower cell viability at 1 µM (0.86±0.04, n=10, p\u3c0.05) and 40 µM (0.40±0.02, n=10, p\u3c0.05) when compared to those of MCF7 cells (1.07±0.05 and 0.68±0.08 for 1 µM and 40 µM, respectively, n=7). By contrast, NIB (10 nM-2 µM) only slightly increased cell viability to 1.13±0.05 (n=11) in H9c2 cells and to 1.16±0.13 (n=7) in MCF7 cells, respectively, when compared to untreated control. The highest tested dose of NIB (5 µM) showed a similar reduction of cell viability to 0.83±0.07 in H9c2 cells and to 0.81±0.10 in MCF7 cells. Furthermore, NIB cotreatment mitigated DOX-induced damages in H9c2 by increasing cell viability to 1.28±0.07 (n=5) and 1.26±0.11 (n=7) when compared to the DOX controls (10 µM and 40µM), respectively. Interestingly, NIB cotreatment enhanced DOX’s anti-cancer effects in by decreasing MCF7 cell viability to 0.66±0.10 (n=7) and 0.70±0.09 (n=6) when compared to the DOX controls (10 µM and 40µM), respectively. The intracellular DOX fluorescence data and NIB pretreatment results are still being gathered. Conclusion DOX, not NIB, dose-dependently induced H9c2 and MCF7 cell death. Moreover, DOX-induced damage was more potent in H9c2 cells than in MCF7 cells. NIB cotreatment mildly protected H9c2 cells against DOX, whereas it increased DOX’s anti-cancer effects in MCF7 cells

Deleterious, protein-altering variants in the transcriptional coregulator ZMYM3 in 27 individuals with a neurodevelopmental delay phenotype

Neurodevelopmental disorders (NDDs) result from highly penetrant variation in hundreds of different genes, some of which have not yet been identified. Using the MatchMaker Exchange, we assembled a cohort of 27 individuals with rare, protein-altering variation in the transcriptional coregulator ZMYM3, located on the X chromosome. Most (n = 24) individuals were males, 17 of which have a maternally inherited variant; six individuals (4 male, 2 female) harbor de novo variants. Overlapping features included developmental delay, intellectual disability, behavioral abnormalities, and a specific facial gestalt in a subset of males. Variants in almost all individuals (n = 26) are missense, including six that recurrently affect two residues. Four unrelated probands were identified with inherited variation affecting Arg441, a site at which variation has been previously seen in NDD-affected siblings, and two individuals have de novo variation resulting in p.Arg1294Cys (c.3880C>T). All variants affect evolutionarily conserved sites, and most are predicted to damage protein structure or function. ZMYM3 is relatively intolerant to variation in the general population, is widely expressed across human tissues, and encodes a component of the KDM1A-RCOR1 chromatin-modifying complex. ChIP-seq experiments on one variant, p.Arg1274Trp, indicate dramatically reduced genomic occupancy, supporting a hypomorphic effect. While we are unable to perform statistical evaluations to definitively support a causative role for variation in ZMYM3, the totality of the evidence, including 27 affected individuals, recurrent variation at two codons, overlapping phenotypic features, protein-modeling data, evolutionary constraint, and experimentally confirmed functional effects strongly support ZMYM3 as an NDD-associated gene

The revised Approved Instructional Resources score: An improved quality evaluation tool for online educational resources

BackgroundFree Open-Access Medical education (FOAM) use among residents continues to rise. However, it often lacks quality assurance processes and residents receive little guidance on quality assessment. The Academic Life in Emergency Medicine Approved Instructional Resources tool (AAT) was created for FOAM appraisal by and for expert educators and has demonstrated validity in this context. It has yet to be evaluated in other populations.ObjectivesWe assessed the AAT's usability in a diverse population of practicing emergency medicine (EM) physicians, residents, and medical students; solicited feedback; and developed a revised tool.MethodsAs part of the Medical Education Translational Resources: Impact and Quality (METRIQ) study, we recruited medical students, EM residents, and EM attendings to evaluate five FOAM posts with the AAT and provide quantitative and qualitative feedback via an online survey. Two independent analysts performed a qualitative thematic analysis with discrepancies resolved through discussion and negotiated consensus. This analysis informed development of an initial revised AAT, which was then further refined after pilot testing among the author group. The final tool was reassessed for reliability.ResultsOf 330 recruited international participants, 309 completed all ratings. The Best Evidence in Emergency Medicine (BEEM) score was the component most frequently reported as difficult to use. Several themes emerged from the qualitative analysis: for ease of use-understandable, logically structured, concise, and aligned with educational value. Limitations include deviation from questionnaire best practices, validity concerns, and challenges assessing evidence-based medicine. Themes supporting its use include evaluative utility and usability. The author group pilot tested the initial revised AAT, revealing a total score average measure intraclass correlation coefficient (ICC) of moderate reliability (ICC = 0.68, 95% confidence interval [CI] = 0 to 0.962). The final AAT's average measure ICC was 0.88 (95% CI = 0.77 to 0.95).ConclusionsWe developed the final revised AAT from usability feedback. The new score has significantly increased usability, but will need to be reassessed for reliability in a broad population