Quality assurance of medical education: Lessons learned from use and analysis of the WFME global standards.

Background: In 2003, the World Federation for Medical Education (WFME) published the Trilogy of Global Standards for Quality Improvement of Medical Education, covering all three phases of education in medicine. The intention was to provide an instrument to be used by medical schools and responsible authorities in quality assurance and improvement of medical education. The standards were revised in 2015. Results: This paper reviews 29 published articles dealing with the practical use and analysis of the standards. 21 papers deal with basic medical education, six with postgraduate medical education and two with CPD. Conclusion: It is concluded that using the WFME standards can be a profitable endeavor with documented impact. Standards should be used as intended, i.e. as a template modified with local specifications.

Using a Virtual Tablet Machine to Improve Student Understanding of the Complex Processes Involved in Tablet Manufacturing.

Objective. To develop and implement a virtual tablet machine simulation to aid distance students' understanding of the processes involved in tablet production. Design. A tablet simulation was created enabling students to study the effects different parameters have on the properties of the tablet. Once results were generated, students interpreted and explained them on the basis of current theory. Assessment. The simulation was evaluated using written questionnaires and focus group interviews. Students appreciated the exercise and considered it to be motivational. Students commented that they found the simulation, together with the online seminar and the writing of the report, was beneficial for their learning process. Conclusion. According to students' perceptions, the use of the tablet simulation contributed to their understanding of the compaction process.

Deamidation and cross-linking of gliadin peptides by transglutaminases and the relation to celiac disease.

Activation of small intestinal gluten-reactive CD4+ T cells is a critical event in celiac disease. Such cells predominantly recognise gluten peptides in which specific glutamines are deamidated. Deamidation may be catalysed by intestinal tissue transglutaminase (TG2), a protein which is also the main autoantigen in celiac disease. Our aim was to study how the two main catalytic activities of transglutaminase--deamidation and transamidation (cross-linking) of an immunodominant gliadin epitope--are influenced by the presence of acceptor amines in the intestinal mucosa, and thereby contribute to further elucidation of the pathogenetic mechanisms in celiac disease. We prepared monoclonal antibodies, reacting specifically with the non-deamidated epitope QPFPQPQLPYPQPQ-amide and/or the deamidated epitope QPFPQPELPYPQPQ-amide. A solid phase immunoassay combined with gel filtration chromatography was used to analyse deamidation and cross-linking of these peptides to proteins. Our results show that QPFPQPQLPYPQPQ-amide was deamidated when incubated with purified TG2, with fresh mucosal sheets and with mucosal homogenates. Of other transglutaminases tested, only Streptoverticillium transglutaminase was able to generate the deamidated epitope. A fraction of the non-deamidated epitope was cross-linked to proteins, including TG2. The results suggest that intestinal TG2 is responsible for generation of the active deamidated epitope. As the epitope often occurs in a repeat structure, the result may be cross-linking of a deamidated, i.e., activated cell epitope. Alternatively, the deamidation may occur by reversal of the cross-linking reaction. The results provide a basis for the suggestion that binding of a peptide to a protein, in connection to its modification to a T cell epitope, might be a general explanation for the role of TG2 in celiac disease and a possible mechanism for the generation of autoantigens.

[Celiac disease--a diagnostic and scientific challenge]. / Cøliaki--en diagnostisk og videnskabelig udfordring.

It is possible that Denmark has a high proportion of patients with undiagnosed coeliac disease in the general population and in such risk groups as patients with autoimmune endocrinological and neurological disorders. An active diagnostic strategy, with screening of patients at risk is proposed. Several gliadin epitopes that might be pathogenetically important are described. Tissue transglutaminase is an autoantigen and a deamidating factor in vitro.

Cellular cross talk in the small intestinal mucosa: postnatal lymphocytic immigration elicits a specific epithelial transcriptional response.

During the early postnatal period lymphocytes migrate into the mouse small intestine. Migrating infiltrative lymphocytes have the potential to affect the epithelial cells via secreted cytokines. Such cross talk can result in the elicitation of an epithelial transcriptional response. Knowledge about such physiological cross talk between the immune system and the epithelium in the postnatal small intestinal mucosa is lacking. We have investigated the transcriptome changes occurring in the postnatal mouse small intestine using DNA microarray technology, immunocytochemistry, and quantitative real-time RT-PCR analysis. The DNA microarray data were analyzed bioinformatically by using a combination of projections to latent structures analysis and functional annotation analysis. The results show that infiltrating lymphocytes appear in the mouse small intestine in the late postweaning period and give rise to distinct changes in the epithelial transcriptome. Of particular interest is the expression of three genes encoding a mucin (Muc4), a mucinlike protein (16000D21Rik), and ATP citrate lyase (Acly). All three genes were shown to be expressed by the epithelium and to be upregulated in response to lymphocytic migration into the small intestinal mucosa.

An upstream polymorphism associated with lactase persistence has increased enhancer activity.

BACKGROUND & AIMS: Intestinal lactase activity declines during childhood in some humans. This phenotypic polymorphism of lactase persistence or nonpersistence into adult life has been shown in a recent study to be 100% associated with a T/C nucleotide polymorphism at position -13910 and approximately 97% with an A/G nucleotide polymorphism at position -22018. The aim of this study was to investigate the role of these nucleotide polymorphisms for lactase-phlorizin hydrolase (LPH) gene expression. METHODS: The -13910 and -22018 regions were cloned from lactase-persistent and -nonpersistent individuals, and the regions were analyzed for gene regulatory activity of a luciferase reporter gene by transfection experiments using the intestinal cell line Caco-2. Electrophoretic mobility shift assays (EMSAs) were used to investigate protein/DNA interactions with the -13910 sequence. RESULTS: We show that the -13910 region contains a strong enhancer. The -13910 regions from both lactase persistent (-13910T variant) and lactase nonpersistent (-13910C variant) have enhancer activity. However, the -13910T variant enhances the LPH promoter approximately 4 times more than the -13910C variant when analyzed in differentiated Caco-2 cells. A nuclear factor from both an intestinal and a nonintestinal extract binds strongly to the -13910T variant whereas the binding to the -13910C variant is much weaker. CONCLUSIONS: The discovery of a functional difference between the 2 alleles at position -13910 supports the notion that the molecular difference between lactase persistence and nonpersistence is caused by the mutation at position -13910.

Secretion of antithrombin is converted from nonpolarized to apical by exchanging its amino terminus for that of apically secreted family members.

The three members of the serpin family, corticosteroid binding globulin, alpha1-antitrypsin, and C1 inhibitor are secreted apically from Madin-Darby canine kidney (MDCK) cells, whereas two homologous family members, antithrombin and plasminogen activator inhibitor-1, are secreted in a nonpolarized fashion. cDNAs coding for chimeras composed of complementary portions of an apically targeted serpin and a nonsorted serpin were generated, expressed in MDCK cells, and the ratio between apical and basolateral secretion was analyzed. These experiments identified an amino-terminal sequence of corticosteroid binding globulin (residues 1-19) that is sufficient to direct a chimera with antithrombin mainly to the apical side. A deletion/mutagenesis analysis showed that no individual amino acid is absolutely required for the apical targeting ability of amino acids 1-30 of corticosteroid binding globulin. The corresponding amino-terminal sequences of alpha1-antitrypsin and C1 inhibitor were also sufficient to confer apical sorting. Based on our results we suggest that the apical targeting ability is encoded in the conformation of the protein.

Serpins are apically secreted from MDCK cells independently of their raft association.

It has been suggested that detergent-resistant membranes (DRMs), also known as lipid rafts, are involved in vectorial transport of proteins to the apical surface. In this report we use Madin-Darby canine kidney (MDCK) cells expressing the apically secreted C1-esterase inhibitor, the non-sorted antithrombin or chimeras of serpins to study the possible connection between DRM association and apical targeting of secretory proteins. We found newly synthesised C1-esterase inhibitor associated with DRMs in MDCK cells, whereas antithrombin was not. However, two chimeric proteins, secreted mainly from the apical membrane, do not associate with DRMs. Based on these observations we suggest that apical targeting and association with DRMs are two independent events for secretory serpins.

Purification, localization, and expression of human intestinal alkaline sphingomyelinase.

Sphingomyelin (SM) metabolism in the gut may have an impact on colon cancer development. In this study, we purified alkaline sphingomyelinase (alk-SMase) from human intestinal content, and studied its location in the mucosa, expression in colon cancer, and function on colon cancer cells. The enzyme was purified by a series of chromatographies. The molecular mass of the enzyme is 60 kDa, optimal pH is 8.5, and isoelectric point is 6.6. Under optimal conditions, 1 mg of the enzyme hydrolyzed 11 mM SM per hour. The properties of the enzyme are similar to those of rat intestinal alk-SMase but not to those of bacterial neutral SMase. Immunogold electronmicroscopy identified the enzyme on the microvillar membrane in endosome-like structures and in the Golgi complexes of human enterocytes. The expression and the activity of the enzyme were decreased in parallel in human colon cancer tissues compared with the adjacent normal tissue. The enzyme inhibited DNA biosynthesis and cell proliferation dose dependently and caused a reduction of SM in HT29 cells. Intestinal alk-SMase is localized in the enterocytes, down-regulated in human colon cancer, and may have antiproliferative effects on colon cancer cells.

Human coronavirus 229E: receptor binding domain and neutralization by soluble receptor at 37 degrees C.

Truncated human coronavirus HCoV-229E spike glycoproteins containing amino acids 407 to 547 bound to purified, soluble virus receptor, human aminopeptidase N (hAPN). Soluble hAPN neutralized the infectivity of HCoV-229E virions at 37 degrees C, but not 4 degrees C. Binding of hAPN may therefore trigger conformational changes in the viral spike protein at 37 degrees C that facilitate virus entry.