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2.
Korean J Med Educ ; 33(4): 393-404, 2021 Dec.
Article in English | MEDLINE | ID: mdl-34875155

ABSTRACT

The required adjustments precipitated by the coronavirus disease 2019 crisis have been challenging, but also represent a critical opportunity for the evolution and potential disruptive and constructive change of medical education. Given that the format of medical education is not fixed, but malleable and in fact must be adaptable to societal needs through ongoing reflexivity, we find ourselves in a potentially transformative learning phase for the field. An Association for Medical Education in Europe ASPIRE Academy group of 18 medical educators from seven countries was formed to consider this opportunity, and identified critical questions for collective reflection on current medical education practices and assumptions, with the attendant challenge to envision the future of medical education. This was achieved through online discussion as well as asynchronous collective reflections by group members. Four major themes and related conclusions arose from this conversation: Why we teach: the humanitarian mission of medicine should be reinforced; what we teach: disaster management, social accountability and embracing an environment of complexity and uncertainty should be the core; how we teach: open pathways to lean medical education and learning by developing learners embedded in a community context; and whom we teach: those willing to take professional responsibility. These collective reflections provide neither fully matured digests of the challenges of our field, nor comprehensive solutions; rather they are offered as a starting point for medical schools to consider as we seek to harness the learning opportunities stimulated by the pandemic.


Subject(s)
COVID-19 , Education, Medical , Humans , Pandemics , SARS-CoV-2 , Schools, Medical
3.
Med Teach ; 43(11): 1255-1260, 2021 11.
Article in English | MEDLINE | ID: mdl-33253603

ABSTRACT

When students attend clinical attachments in diverse locations, a key challenge is in ensuring consistently good teaching over all areas. To meet this challenge, a faculty development intervention called TiMEtoTeach was created with the aim of reaching all involved in teaching medical students. The programme takes a holistic view of workplace (professional clinical attachments) learning with the recognition of all who are part of the student learning journey, including staff in clinical environments, charitable organisations, fellow students and the patients and carers. Empowering and upskilling this diverse group, we create a Universal Faculty. We engage this group with a comprehensive and accessible faculty development programme, enabling a consistent, authentic, and realistic learning experience for students. This supports graduate preparedness for their roles as junior doctors. The twelve tips described in this article relate to simple, achievable processes that faculty developers within medical education can apply to help improve consistency and quality in clinical workplace experience for students, recognising the challenges of engaging the large and diverse group of people who support education within the clinical arena.


Subject(s)
Education, Medical , Students, Medical , Faculty , Faculty, Medical , Humans , Learning , Medical Staff, Hospital , Teaching
4.
J Virol ; 89(4): 2052-63, 2015 Feb.
Article in English | MEDLINE | ID: mdl-25428878

ABSTRACT

UNLABELLED: The RNA-dependent RNA polymerase (RdRp) of hepatitis C virus (HCV) is essential for viral genome replication. Crystal structures of the HCV RdRp reveal two C-terminal features, a ß-loop and a C-terminal arm, suitably located for involvement in positioning components of the initiation complex. Here we show that these two elements intimately regulate template and nucleotide binding, initiation, and elongation. We constructed a series of ß-loop and C-terminal arm mutants, which were used for in vitro analysis of RdRp de novo initiation and primer extension activities. All mutants showed a substantial decrease in initiation activities but a marked increase in primer extension activities, indicating an ability to form more stable elongation complexes with long primer-template RNAs. Structural studies of the mutants indicated that these enzyme properties might be attributed to an increased flexibility in the C-terminal features resulting in a more open polymerase cleft, which likely favors the elongation process but hampers the initiation steps. A UTP cocrystal structure of one mutant shows, in contrast to the wild-type protein, several alternate conformations of the substrate, confirming that even subtle changes in the C-terminal arm result in a more loosely organized active site and flexible binding modes of the nucleotide. We used a subgenomic replicon system to assess the effects of the same mutations on viral replication in cells. Even the subtlest mutations either severely impaired or completely abolished the ability of the replicon to replicate, further supporting the concept that the correct positioning of both the ß-loop and C-terminal arm plays an essential role during initiation and in HCV replication in general. IMPORTANCE: HCV RNA polymerase is a key target for the development of directly acting agents to cure HCV infections, which necessitates a thorough understanding of the functional roles of the various structural features of the RdRp. Here we show that even highly conservative changes, e.g., Tyr→Phe or Asp→Glu, in these seemingly peripheral structural features have profound effects on the initiation and elongation properties of the HCV polymerase.


Subject(s)
Hepacivirus/enzymology , Hepacivirus/physiology , RNA-Dependent RNA Polymerase/metabolism , Transcription Elongation, Genetic , Transcription Initiation, Genetic , Virus Replication , Crystallography, X-Ray , DNA Mutational Analysis , Hepacivirus/chemistry , Hepacivirus/genetics , Humans , Mutant Proteins/chemistry , Mutant Proteins/genetics , Mutant Proteins/metabolism , Protein Conformation , RNA-Dependent RNA Polymerase/chemistry , RNA-Dependent RNA Polymerase/genetics
5.
J Mol Biol ; 413(1): 41-50, 2011 Oct 14.
Article in English | MEDLINE | ID: mdl-21839089

ABSTRACT

A codon-optimised gene has been expressed in Escherichia coli to produce the coat protein (CP) of the Satellite Tobacco Necrosis Virus. This protein assembles in vivo into capsids closely resembling those of the T=1 wild-type virus. These virus-like particles (VLPs) package the recombinant mRNA transcript and can be disassembled and reassembled using different buffer conditions. The X-ray crystal structure of the VLP has been solved and refined at 1.4 Å resolution and shown to be very similar to that of wild-type Satellite Tobacco Necrosis Virus, except that icosahedral symmetry constraints could be removed to reveal differences between subunits, presumably owing to crystal packing. An additional low-resolution X-ray crystal structure determination revealed well-ordered RNA fragments lodged near the inside surface of the capsid, close to basic clusters formed by the N-terminal helices that project into the interior of the particle. The RNA consists of multiple copies of a 3-bp helical stem, with a single unpaired base at the 3' end, and probably consists of a number of short stem-loops where the loop region is disordered. The arrangement of the RNA is different from that observed in other satellite viruses.


Subject(s)
Capsid Proteins/chemistry , Capsid Proteins/metabolism , Capsid/chemistry , Protein Multimerization , Tobacco necrosis satellite virus/chemistry , Capsid Proteins/genetics , Crystallography, X-Ray , Escherichia coli/genetics , Models, Molecular , Protein Binding , Protein Structure, Quaternary , RNA, Viral/chemistry
6.
Proteins ; 60(4): 658-69, 2005 Sep 01.
Article in English | MEDLINE | ID: mdl-16021629

ABSTRACT

We have studied the solution properties of Nef, a 24-kDa cotranslationally myristoylated protein produced by HIV-1 and other primate lentiviruses. Nef is found in the cytosol and also in association with cytoplasmic membranes, the latter, mediated in part by the myristoyl group attached to the N-terminal glycine. Recombinant Nef was coexpressed in Escherichia coli in tandem with N-myristoyl-transferase and is fully myristoylated. Analysis by circular dichroism showed the myristoylated form to contain a greater alpha-helical content than the nonmyristoylated form. Analysis of modified and unmodified Nef in solution using small angle X-ray scattering, dynamic laser light scattering and analytical ultracentrifugation consistently showed differences in the oligomeric states of the two forms of Nef. Myristoylated Nef is predominantly monomeric and small oligomers which are also present, can be converted to the monomeric form under reducing conditions. By contrast, the nonmyristoylated form exists as a stable hexadecamer in solution which disassociates into tetramers upon addition of reducing agents. Shape reconstructions from small angle scattering curves of nonmyristoylated Nef are compatible with a large disc-like structure in the hexadecameric oligomer consisting of four Nef tetramers. From these findings, we hypothesize that Nef undergoes a substantial conformational change from an "open" into a "closed" form whereby the myristate group is sequestered in a hydrophobic pocket. The myristoylated protein can switch to the open conformation by association of the N-terminal region of molecule with membranes. These changes would allow Nef to carry out various functions depending on the conformational and oligomeric states.


Subject(s)
Gene Products, nef/chemistry , Gene Products, nef/metabolism , Myristic Acids , Protein Biosynthesis , Protein Structure, Quaternary , Base Sequence , Binding Sites , Gene Products, nef/genetics , HIV-1/chemistry , Molecular Sequence Data , Polymerase Chain Reaction , Protein Conformation , Recombinant Proteins/chemistry , Recombinant Proteins/metabolism , Restriction Mapping , Solutions , nef Gene Products, Human Immunodeficiency Virus
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