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Misalignments in teaching pedagogies between secondary schools and tertiary institutions have exacerbated educational disparities among students from different backgrounds. Given the variation in students' educational background and competencies, there was a need to develop an Anatomy and Physiology (AP) Foundational Knowledge Assessment to establish the levels of preparedness of first-year medical students. Previous work that focused on the development of the assessment showed it to be effective in measuring students' foundational knowledge in human anatomy and physiology. The aim of this study was to assess the validity of the AP Foundational Knowledge Assessment in determining students' prior knowledge and predicting academic performance of first-year students in their anatomy and physiology studies. Three hundred seventy first-year students, across two cohort years, 2017 and 2018, completed the AP Foundational Knowledge Assessment. Data were analyzed through descriptive statistics, analysis of variance, and Pearson's correlation. Results show that for both cohorts ∼30% of students scored ≤55% and were potentially at risk of performing poorly in their anatomy and physiology studies. Pearson's correlation showed a significant relationship between students' performance on the foundational knowledge assessment and their anatomy and physiology assessments. For both cohorts,10% of students identified by the AP Foundational Knowledge Assessment were at risk of either failing the course, entering an extended degree program, or being excluded from the program. Results indicate that the assessment is a good predictor for differentiating medical students' performance in first-year anatomy and physiology.

Research on the extent and nature of commonly misunderstood fundamental biomedical concepts across a medical curriculum is scarce. These misunderstandings could point toward robust misconceptions. We examined first whether common misunderstandings persist throughout a medical curriculum, followed by a fine-grained analysis to identify their nature. We designed and administered a 2-tier test to 987 medical students across our curriculum, with 8 questions covering the respiratory and cardiovascular systems, cell division, and homeostatic processes. Proportions of incorrect responses were computed. Four questions where misunderstandings persisted were further qualitatively analyzed. A one-way ANOVA showed the proportion of incorrect responses decreased significantly by students’ academic year [ F(6, 986) = 96.05, P < 0.001]. While novices and end-of -first-year students showed similar proportion of incorrect responses ( P > 0.05), incorrect responses decreased significantly between first years and second years ( P < 0.001). Thereafter, the proportion of incorrect responses remained stable from second to final year ( P > 0.05), with ∼35% of incorrect responses. Five questions showed no decrease of incorrect responses between second and final years, with two questions where final year students performed marginally better than novices. A Chi-square analysis, with Bonferroni post hoc test, showed certain misunderstandings appeared frequently across the curriculum. The qualitative analysis of the open-ended questions yielded 15 categories of common misunderstandings of fundamental biomedical concepts in all years of training. If educators become aware of commonly misunderstood biomedical concepts, preventative measures could be taken to prevent robust misconceptions.

International audience; The stress-activated p38α MAP Kinase is an integral and critical component of the UV-induced inflammatory response. Despite the advances in recent years in the development of p38 kinase inhibitors, validation of these compounds in the diseased models remains limited. Based on the pharmacological profile of p38α inhibitor lead compound, SB203580, we synthesized a series of pyrrole-derivatives. Using UV-irradiated human skin punch-biopsies and cell cultures, we identified and validated the inhibitory activity of the derivatives by quantitatively measuring their effect on the expression of p38α target genes using real-time PCR. This approach not only identified pyrrole-2 as a unique derivative of this series that specifically inhibited the UV-activated p38α kinase, but also documented the skin permeation, bioavailability and reversible properties of this derivative in a 3D structure. The successful skin permeation of pyrrole-2 and its impact on AREG, COX-2 and MMP-9 gene expression demonstrates its potential use in modulating inflammatory processes in the skin. This study underscored the importance of using adapted biological models to identify accurate bioactive compounds.

The present study explored the nature and frequency of physiology naïve beliefs by investigating novices' understanding of the respiratory system. Previous studies have shown considerable misconceptions related to physiology but focused mostly on specific physiological processes of normal respiration. Little is known about novices' broader understanding of breathing in a clinical context. Our study hypothesized that naïve beliefs could hamper participants' ability to understand the interrelatedness of respiratory structures and functions related to breathing during a clinical complication. The study entailed both quantitative and qualitative foci. A two-tier test was designed and administered to 211 first-year medical students. Participants were asked to choose the correct answer out of a set of four options and to substantiate their choices. Questions were purposefully left open to elicit a wide range of responses. Statistical analysis (SPSS) was done to evaluate the frequency of naïve beliefs. Thematic analysis was used to determine themes within the raw data. The majority of participants selected incorrect answers in the multiple-choice question part of the questionnaire. Results from the thematic analysis yielded a considerable range of naïve beliefs about gas exchange, foundational physics, airflow, anatomic structures, and breathing pathways. An awareness of the existence of such naive beliefs in respiratory physiology will allow educators to address them in their teaching and thereby prevent naïve beliefs transforming into misconceptions.

Decay accelerating factor (DAF) expression at the muscle endplate is an important defence against complement-mediated damage in myasthenia gravis. Previously we implicated the c.-198C > G DAF polymorphism with the development of treatment-resistant myasthenia-associated ophthalmoplegia by showing that the C > G DAF polymorphism prevented lipopolysaccharide-induced upregulation of lymphoblast DAF. We postulated that drugs used in myasthenia gravis may increase the susceptibility of extraocular muscles to complement-mediated damage and studied their effects on endogenous DAF using patient-derived lymphoblasts as well as mouse myotubes. We show that prednisone repressed C > G DAF expression in lymphoblasts and increased their susceptibility to cytotoxicity. Methotrexate, but not azathioprine or cyclosporine, increased DAF in C > G lymphoblasts. In mouse myotubes expressing wild-type Daf, prednisone also repressed Daf expression. Although cyclosporine, azathioprine, and methotrexate increased muscle Daf levels when used alone, upon co-treatment with prednisone only azathioprine maintained myotube Daf levels close to basal. Therefore, prednisone negatively influences DAF expression in C > G lymphoblasts and in myotubes expressing wild-type Daf. We speculate that myasthenic individuals at risk of developing the ophthalmoplegic complication, such as those with C > G DAF, may have inadequate endogenous levels of complement regulatory protein protection in their extraocular muscle in response to prednisone, increasing their susceptibility to complement-mediated damage. 2014 Elsevier B.V. All rights reserved.

The T-box gene family encodes highly conserved transcription factors that play important roles in embryonic development and have been implicated in carcinogenesis. One member of the family, Tbx2, is generally regarded as a transcriptional repressor but appears to be capable of functioning as an activator depending on the cellular context. This study shows that Tbx2 is expressed in normal human fibroblasts but is drastically reduced in several transformed fibroblast cell lines. This pattern of Tbx2 expression correlated with that observed for the human alpha2(1) collagen gene (COL1A2). Interestingly, stable expression of transfected Tbx2 in transformed fibroblast cell lines further reduces expression of the human endogenous COL1A2 gene. This ability of Tbx2 to repress the human COL1A2 gene was confirmed in luciferase reporter assays and shown to be independent of the consensus T-box binding element.

The transcription factor, TBX3, is critical for the formation of, among other structures, the heart, limbs and mammary glands and haploinsufficiency of the human TBX3 gene result in ulnar-mammary syndrome which is characterized by hypoplasia of these structures. On the other hand, the overexpression of TBX3 is a feature of a wide range of cancers and it has been implicated in several aspects of the oncogenic process. This includes its ability to function as an immortalizing gene and to promote proliferation through actively repressing negative cell cycle regulators. Together this suggests that TBX3 levels may need to be tightly regulated during the cell cycle. Here we demonstrate that this is indeed the case and that TBX3 mRNA and protein levels peak at S-phase and that the TBX3 protein is predominantly localized to the nucleus of S-phase cells. The increased levels of TBX3 in S-phase are shown to occur transcriptionally through activation by c-Myc at E-box motifs located at -1210 and -701 bps and post-translationally by cyclin A-CDK2 phosphorylation. Importantly, when TBX3 is depleted by shRNA the cells accumulate in S-phase. These results suggest that TBX3 is required for cells to transit through S-phase and that this function may be linked to its role as a pro-proliferative factor.

Tbx2 is a member of the T-box family of transcription factors that are crucial in embryonic development. Recent studies suggest that T-box factors may also play a role in controlling cell cycle progression and in the genesis of cancer. Tbx2 has been implicated in several developmental processes such as coordinating cell fate, patterning and morphogenesis of a wide range of tissues and organs including limbs, kidneys, lungs, mammary glands, heart, and craniofacial structures. Importantly, Tbx2 is overexpressed in several cancers including melanoma, small cell lung carcinoma, breast, pancreatic, liver, and bladder cancers and can suppress senescence, a cellular process, which serves as a barrier to cancer development. This review presents a state of the art overview of the role and regulation of Tbx2 in early embryonic development and in cancer. © 2009 IUBMB IUBMB Life, 62(2): 92–102, 2010

Several lines of evidence have implicated members of the developmentally important T-box gene family in cell cycle regulation and in cancer. Importantly, the highly related T-box factors Tbx2 and Tbx3 can suppress senescence through repressing the cyclin-dependent kinase inhibitors p19(ARF) and p21(WAF1/CIP1/SDII). Furthermore, Tbx2 is up-regulated in several cancers, including melanomas where it was shown to function as an anti-senescence factor, suggesting that this may be one of the mechanisms by which T-box proteins contribute to the oncogenic process. However, very little is known about whether Tbx2 is regulated by p21-mediated stress-induced senescence signaling pathways. In this study, using the MCF-7 breast cancer cell line known to overexpress Tbx2, we show that in response to stress induced by ultraviolet irradiation the Tbx2 protein is specifically phosphorylated by the p38 mitogen-activated protein kinase. Using site-directed mutagenesis and in vitro kinase assays, we have identified serine residues 336, 623, and 675 in the Tbx2 protein as the p38 target sites and show that these sites are phosphorylated in vivo. Importantly, we show by Western blotting, immunofluorescence, and reporter assays that this phosphorylation leads to increased Tbx2 protein levels, predominant nuclear localization of the protein, and an increase in the ability of Tbx2 to repress the p21(WAF1/CIP1/SDII) promoter. These results show for the first time that the ability of Tbx2 to repress the p21 gene is enhanced in response to a stress-induced senescence pathway, which leads to a better understanding of the regulation of the anti-senescence function of Tbx2.

T-box factors play a crucial role in the development of many tissues, and mutations in T-box factor genes have been implicated in multiple human disorders. Some T-box factors have been implicated in cancer; for example, Tbx2 and Tbx3 can suppress replicative senescence, whereas Tbx3 can cooperate with Myc and Ras in cellular transformation. The p21WAF1 cyclin-dependent kinase inhibitor plays a key role in senescence and in cell cycle arrest after DNA damage. Here, using a combination of in vitro DNA-binding, transfection, and chromatin immunoprecipitation assays, we show that Tbx2 can bind and repress the p21 promoter in vitro and in vivo. Moreover, small interfering RNA-mediated down-regulation of Tbx2 expression results in a robust activation of p21 expression. Taken together, these results implicate Tbx2 as a novel direct regulator of p21 expression and have implications for our understanding of the role of T-box factors in the regulation of senescence and oncogenesis, as well as in development.