KPNA2 is a nuclear export protein that contributes to aberrant localisation of key proteins and poor prognosis of breast cancer

Background: It is recognised that modulations of the nuclear import of macromolecules have a role in changing cellular phenotypes and carcinogenesis. We and others have noticed that aberrant subcellular localisation of DNA damage response (DDR) proteins in breast cancer (BC) is associated with loss-of-function phenotype. This study aims to investigate the biological and clinical significance of the nucleocytoplasmic transport protein karyopherin a-2 (KPNA2), and its role in controlling DDR proteins subcellular localisation in BC.Methods: A large (n=1494) and well-characterised series of early-stage invasive BC with a long-term follow-up was assessed for KPNA2 protein by using immunohistochemistry.Results: KPNA2 expression was associated with the subcellular localisation of key DDR proteins that showed cytoplasmic expression including BRCA1, RAD51, SMC6L1, gammaH2AX, BARD1, UBC9, PIAS1 and CHK1. High level of KPNA2 was associated not only with cytoplasmic localisation of these proteins but also with their low/negative nuclear expression. Positive KPNA2 expression was associated with negative oestrogen receptor and triple-negative phenotype. Survival analysis showed that KPNA2 was associated with poor outcome (P less than 0.0001), but this effect was not independent of other prognostic variables.Conclusions: This study provides further evidence for the complexity of DDR mechanism in BC, and that KNPA2 has a role in the aberrant subcellular localisation of DDR proteins with subsequent impaired function

Learning style preferences of dental students at a single institution in Riyadh, Saudi Arabia, evaluated using the VARK questionnaire

Mohammad A Aldosari, Aljazi H Aljabaa, Fares S Al-Sehaibany, Sahar F Albarakati Department of Pediatric Dentistry and Orthodontics, College of Dentistry, King Saud University, Riyadh, Saudi Arabia Background: Students differ in their preferred methods of acquiring, processing, and recalling new information. The aim of this study was to investigate the learning style preferences of undergraduate dental students and examine the influence of gender, Grade Point Average (GPA), and academic year levels on these preferences.Methods: The Arabic version of the visual, aural, read/write, and kinesthetic (VARK) questionnaire was administered to 491 students from the first- to the fifth-year academic classes at the College of Dentistry, King Saud University. Descriptive statistics were used to characterize the learning styles of the students, and Chi-square test and Fisher’s test were used to compare the learning preferences between genders and among academic years. Significance was set at a p-value of <0.05.Results: A total of 368 dental students completed the questionnaire. The multimodal learning style was preferred by 63.04% of the respondents, with the remaining 36% having a unimodal style preference. The aural (A) and the kinesthetic (K) styles were the most preferred unimodal styles. The most common style overall was the quadmodal (VARK) style with 23.64% having this preference. These differences did not reach statistical significance (p>0.05). Females were more likely to prefer a bimodal learning style over a unimodal style (relative risk =2.37). Students with a GPA of “C” were less likely to have a bimodal or a quadmodal style preference compared to students with a GPA of “A” (relative risk =0.34 and 0.36, respectively). Second-year students were less likely to prefer a bimodal over a unimodal style compared to first-year students (relative risk =0.34).Conclusion: The quadmodal VARK style is the preferred learning method chosen by dental students, followed by unimodal aural and kinesthetic styles. Gender was found to influence learning style preferences. Students with a “C” GPA tend to prefer unimodal learning style preferences. The VARK questionnaire is a relatively quick and simple tool to reveal the learning style preferences on an individual or a group level. Dental educators should adjust their delivery methods to approximate the learning preferences of their students. Dental students are encouraged to adapt a multimodal style of learning to improve their academic results. Keywords: VARK, learning styles, dental students, gender, learning preference

Combined photographic and ultrasonographic measurement of the ANB angle: a pilot study

Objective: This study was performed to evaluate the feasibility of noninvasive measurement of the ANB angle using photographic and ultrasonographic methods. Methods: Twenty consecutive orthodontic patients were evaluated. The ANB angle and soft tissue thickness covering the N, A, and B cephalometric points were measured by lateral teleradiography; these measurements were made by two expert operators. The soft tissue thickness covering the N, A, and B cephalometric points was measured by ultrasonography; these measurements were also made by two expert operators. On a 1:1 photographic profile print on which the ultrasonographic points were marked, the ANB ultrasonographic angle was measured. The following comparisons were considered: averaged and single measurements of N, A, and B points by first versus second ultrasonographer; averaged and single ultrasonographic versus radiographic soft tissue thickness covering the N, A, B points; and averaged and single ultrasonographic versus radiographic measurements of ANB angle. Results: High correlation and concordance of the averaged and single measurements, but no significant difference, was found between the two ultrasonographers. No statistically significant difference was found between the two methods for measuring averaged soft tissue thickness, but a 20% difference was found for the single measurements. High correlation and concordance between the ultrasonographic and radiographic measurements, but no significant difference, was found between the single and averaged ANB angle measurements. Conclusion: Ultrasonography seems to be a noninvasive and reliable technique for measurement of the ANB angle and may replace radiographic measurement in some cases