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1.
MedEdPublish (2016) ; 13: 127, 2023.
Article in English | MEDLINE | ID: mdl-38144874

ABSTRACT

Background: Globally, tertiary teachers are increasingly being pushed and pulled into online teaching. While most developments in online education have focused on the student perspective, few studies have reported faculty development (FD) initiatives for increasing online teaching capability and confidence from a staff perspective. Methods: We designed and evaluated FD workshops, using five datasets, and the use of H5P software for interactive online teaching. We used educational theory to design our FD (Mayer multimedia principles, active learning) and evaluated our FD initiatives using the Best Evidence Medical Education (BEME) 2006 modified Kirkpatrick levels. Results: Teaching staff reported that Communities of Practice were important for their learning and emotional support. Uptake and deployment of FD skills depended on the interactivity of FD sessions, their timeliness, and sufficient time allocated to attend and implement. Staff who applied FD learning to their online teaching created interactive learning resources. This content was associated with an increase in student grades, and the roll-out of an institutional site-wide H5P license. Conclusion: This paper demonstrates an effective strategy for upskilling and upscaling faculty development. The use of H5P as a teaching tool enhances student learning. For successful FD, we make four recommendations. These are: provide just-in-time learning and allocate time for FD and staff to create online teaching material; foster supportive communities; offer personalized support; and design hands on active learning.

2.
Trends Mol Med ; 29(12): 971-973, 2023 12.
Article in English | MEDLINE | ID: mdl-37718142

ABSTRACT

Generative artificial intelligence (GAI) large language models (LLMs), like ChatGPT, have become the world's fastest growing applications. Here, we provide useful strategies for educators in medical and health science (M&HS) to integrate GAI-LLMs into learning and teaching practice, ultimately enhancing students' digital capability.


Subject(s)
Artificial Intelligence , Education, Medical , Humans , Language
3.
Proc Natl Acad Sci U S A ; 111(11): 4031-6, 2014 Mar 18.
Article in English | MEDLINE | ID: mdl-24550447

ABSTRACT

2-Oxoglutarate (2OG) and Fe(II)-dependent oxygenase domain-containing protein 1 (OGFOD1) is predicted to be a conserved 2OG oxygenase, the catalytic domain of which is related to hypoxia-inducible factor prolyl hydroxylases. OGFOD1 homologs in yeast are implicated in diverse cellular functions ranging from oxygen-dependent regulation of sterol response genes (Ofd1, Schizosaccharomyces pombe) to translation termination/mRNA polyadenylation (Tpa1p, Saccharomyces cerevisiae). However, neither the biochemical activity of OGFOD1 nor the identity of its substrate has been defined. Here we show that OGFOD1 is a prolyl hydroxylase that catalyzes the posttranslational hydroxylation of a highly conserved residue (Pro-62) in the small ribosomal protein S23 (RPS23). Unusually OGFOD1 retained a high affinity for, and forms a stable complex with, the hydroxylated RPS23 substrate. Knockdown or inactivation of OGFOD1 caused a cell type-dependent induction of stress granules, translational arrest, and growth impairment in a manner complemented by wild-type but not inactive OGFOD1. The work identifies a human prolyl hydroxylase with a role in translational regulation.


Subject(s)
Carrier Proteins/metabolism , Nuclear Proteins/metabolism , Prolyl Hydroxylases/metabolism , Protein Biosynthesis/physiology , Protein Processing, Post-Translational/physiology , Ribosomal Proteins/metabolism , Analysis of Variance , Carrier Proteins/genetics , Computational Biology , Fluorescent Antibody Technique , Gene Knockdown Techniques , Humans , Hydroxylation , Immunoblotting , Immunoprecipitation , Ketoglutaric Acids/metabolism , Luciferases , Nuclear Proteins/genetics , Proline/metabolism , Protein Biosynthesis/genetics , Yeasts
4.
EMBO Rep ; 13(3): 251-7, 2012 Mar 01.
Article in English | MEDLINE | ID: mdl-22310300

ABSTRACT

Hypoxic and oxidant stresses can coexist in biological systems, and oxidant stress has been proposed to activate hypoxia pathways through the inactivation of the 'oxygen-sensing' hypoxia-inducible factor (HIF) prolyl and asparaginyl hydroxylases. Here, we show that despite reduced sensitivity to cellular hypoxia, the HIF asparaginyl hydroxylase--known as FIH, factor inhibiting HIF--is strikingly more sensitive to peroxide than the HIF prolyl hydroxylases. These contrasting sensitivities indicate that oxidant stress is unlikely to signal hypoxia directly to the HIF system, but that hypoxia and oxidant stress can interact functionally as distinct regulators of HIF transcriptional output.


Subject(s)
Hypoxia-Inducible Factor 1, alpha Subunit/metabolism , Mixed Function Oxygenases/metabolism , Peroxides/metabolism , Repressor Proteins/metabolism , Cell Hypoxia/genetics , Cell Line , Cysteine/metabolism , Gene Expression Regulation/drug effects , Humans , Hydroxylation/drug effects , Mixed Function Oxygenases/antagonists & inhibitors , Peroxides/pharmacology , Repressor Proteins/antagonists & inhibitors , Transcription, Genetic
5.
J Biol Chem ; 286(39): 33784-94, 2011 Sep 30.
Article in English | MEDLINE | ID: mdl-21808058

ABSTRACT

The asparaginyl hydroxylase, factor-inhibiting hypoxia-inducible factor (HIF), is central to the oxygen-sensing pathway that controls the activity of HIF. Factor-inhibiting HIF (FIH) also catalyzes the hydroxylation of a large set of proteins that share a structural motif termed the ankyrin repeat domain (ARD). In vitro studies have defined kinetic properties of FIH with respect to different substrates and have suggested FIH binds more tightly to certain ARD proteins than HIF and that ARD hydroxylation may have a lower K(m) value for oxygen than HIF hydroxylation. However, regulation of asparaginyl hydroxylation on ARD substrates has not been systematically studied in cells. To address these questions, we employed isotopic labeling and mass spectrometry to monitor the accrual, inhibition, and decay of hydroxylation under defined conditions. Under the conditions examined, hydroxylation was not reversed but increased as the protein aged. The extent of hydroxylation on ARD proteins was increased by addition of ascorbate, whereas iron and 2-oxoglutarate supplementation had no significant effect. Despite preferential binding of FIH to ARD substrates in vitro, when expressed as fusion proteins in cells, hydroxylation was found to be more complete on HIF polypeptides compared with sites within the ARD. Furthermore, comparative studies of hydroxylation in graded hypoxia revealed ARD hydroxylation was suppressed in a site-specific manner and was as sensitive as HIF to hypoxic inhibition. These findings suggest that asparaginyl hydroxylation of HIF-1 and ARD proteins is regulated by oxygen over a similar range, potentially tuning the HIF transcriptional response through competition between the two types of substrate.


Subject(s)
Hypoxia-Inducible Factor 1/metabolism , Mixed Function Oxygenases/metabolism , Oxygen/metabolism , Repressor Proteins/metabolism , Transcription, Genetic , Animals , Ankyrin Repeat , Cell Hypoxia , HEK293 Cells , Humans , Hydroxylation , Hypoxia-Inducible Factor 1/genetics , Mass Spectrometry , Mice , Mixed Function Oxygenases/genetics , Protein Binding , Protein Structure, Tertiary , Repressor Proteins/genetics
6.
Cancer Res ; 70(4): 1573-84, 2010 Feb 15.
Article in English | MEDLINE | ID: mdl-20145130

ABSTRACT

PR-104, currently in phase II clinical trials, is a phosphate ester pre-prodrug which is converted in vivo to its cognate alcohol, PR-104A, a prodrug designed to exploit tumor hypoxia. Bioactivation occurs via one-electron reduction to DNA crosslinking metabolites in the absence of oxygen. However, certain tumor cell lines activate PR-104A in the presence of oxygen, suggesting the existence of an aerobic nitroreductase. Microarray analysis identified a cluster of five aldo-keto reductase (AKR) family members whose expressions correlated with aerobic metabolism of PR-104A. Plasmid-based expression of candidate genes identified aldo-keto reductase 1C3 as a novel nitroreductase. AKR1C3 protein was detected by Western blot in 7 of 23 cell lines and correlated with oxic PR-104A metabolism, an activity which could be partially suppressed by Nrf2 RNAi knockdown (or induced by Keap1 RNAi), indicating regulation by the ARE pathway. AKR1C3 was unable to sensitize cells to 10 other bioreductive prodrugs and was associated with single-agent PR-104 activity across a panel of 9 human tumor xenograft models. Overexpression in two AKR1C3-negative tumor xenograft models strongly enhanced PR-104 antitumor activity. A population level survey of AKR1C3 expression in 2,490 individual cases across 19 cancer types using tissue microarrays revealed marked upregulation of AKR1C3 in a subset including hepatocellular, bladder, renal, gastric, and non-small cell lung carcinoma. A survey of normal tissue AKR1C3 expression suggests the potential for tumor-selective PR-104A activation by this mechanism. These findings have significant implications for the clinical development of PR-104.


Subject(s)
3-Hydroxysteroid Dehydrogenases/metabolism , Aerobiosis/physiology , Hydroxyprostaglandin Dehydrogenases/metabolism , Nitrogen Mustard Compounds/pharmacokinetics , 3-Hydroxysteroid Dehydrogenases/genetics , 3-Hydroxysteroid Dehydrogenases/physiology , Aldo-Keto Reductase Family 1 Member C3 , Animals , Cell Line, Tumor , Drug Resistance, Neoplasm/drug effects , Drug Resistance, Neoplasm/genetics , Female , Gene Expression Regulation, Enzymologic , Gene Expression Regulation, Neoplastic , HCT116 Cells , HT29 Cells , Humans , Hydroxyprostaglandin Dehydrogenases/genetics , Hydroxyprostaglandin Dehydrogenases/physiology , Inhibitory Concentration 50 , Mice , Mice, Nude , Models, Biological , Nitrogen Mustard Compounds/metabolism , Oxidation-Reduction/drug effects , Oxygen/pharmacology , Prodrugs/metabolism , Prodrugs/pharmacokinetics , Tissue Array Analysis , Xenograft Model Antitumor Assays
7.
Cancer Res ; 69(9): 3884-91, 2009 May 01.
Article in English | MEDLINE | ID: mdl-19366798

ABSTRACT

PR-104, currently in clinical trial, is converted systemically to the dinitrobenzamide nitrogen mustard prodrug PR-104A, which is reduced selectively in hypoxic cells to cytotoxic hydroxylamine (PR-104H) and amine (PR-104M) metabolites. Here, we evaluate the roles of this reductive metabolism, and DNA interstrand cross-links (ICL), in the hypoxic and aerobic cytotoxicity of PR-104. Using a panel of 9 human tumor cell lines, cytotoxicity was determined by clonogenic assay after a 2-hour aerobic or hypoxic exposure to PR-104A. PR-104H and PR-104M were determined by high performance liquid chromatography/mass spectrometry, and ICL with the alkaline comet assay. Under hypoxia, the relationship between ICL and cell killing was similar between cell lines. Under aerobic conditions, there was a similar relationship between ICL and cytotoxicity, except in lines with very low rates of aerobic reduction of PR-104A (A2780, C33A, H1299), which showed an ICL-independent mechanism of PR-104A cytotoxicity. Despite this, in xenografts from the same lines, the frequency of PR-104-induced ICL correlated with clonogenic cell killing (r(2) = 0.747) with greatest activity in the fast aerobic metabolizers. In addition, changing levels of hypoxia in SiHa tumors modified both ICL frequency and tumor growth delay in parallel. We conclude that both aerobic and hypoxic nitroreduction of PR-104A contribute to the monotherapy antitumor activity of PR-104 in human tumor xenografts, and that ICL are responsible for its antitumor activity and represent a broadly applicable biomarker for tumor cell killing by this novel prodrug.


Subject(s)
DNA Damage , DNA, Neoplasm/drug effects , Neoplasms/metabolism , Nitrogen Mustard Compounds/pharmacology , Animals , Cell Death/drug effects , Cell Hypoxia , Cell Line, Tumor , Chlorambucil , Chromatography, Liquid , DNA, Neoplasm/metabolism , Female , HCT116 Cells , HT29 Cells , Humans , Mice , Mice, Nude , Neoplasms/drug therapy , Neoplasms/genetics , Neoplasms/pathology , Nitrogen Mustard Compounds/pharmacokinetics , Prodrugs/pharmacokinetics , Prodrugs/pharmacology , Tandem Mass Spectrometry , Xenograft Model Antitumor Assays
8.
Clin Cancer Res ; 13(13): 3922-32, 2007 Jul 01.
Article in English | MEDLINE | ID: mdl-17606726

ABSTRACT

PURPOSE: Hypoxia is a characteristic of solid tumors and a potentially important therapeutic target. Here, we characterize the mechanism of action and preclinical antitumor activity of a novel hypoxia-activated prodrug, the 3,5-dinitrobenzamide nitrogen mustard PR-104, which has recently entered clinical trials. EXPERIMENTAL DESIGN: Cytotoxicity in vitro was evaluated using 10 human tumor cell lines. SiHa cells were used to characterize metabolism under hypoxia, by liquid chromatography-mass spectrometry, and DNA damage by comet assay and gammaH2AX formation. Antitumor activity was evaluated in multiple xenograft models (PR-104 +/- radiation or chemotherapy) by clonogenic assay 18 h after treatment or by tumor growth delay. RESULTS: The phosphate ester "pre-prodrug" PR-104 was well tolerated in mice and converted rapidly to the corresponding prodrug PR-104A. The cytotoxicity of PR-104A was increased 10- to 100-fold by hypoxia in vitro. Reduction to the major intracellular metabolite, hydroxylamine PR-104H, resulted in DNA cross-linking selectively under hypoxia. Reaction of PR-104H with chloride ion gave lipophilic cytotoxic metabolites potentially able to provide bystander effects. In tumor excision assays, PR-104 provided greater killing of hypoxic (radioresistant) and aerobic cells in xenografts (HT29, SiHa, and H460) than tirapazamine or conventional mustards at equivalent host toxicity. PR-104 showed single-agent activity in six of eight xenograft models and greater than additive antitumor activity in combination with drugs likely to spare hypoxic cells (gemcitabine with Panc-01 pancreatic tumors and docetaxel with 22RV1 prostate tumors). CONCLUSIONS: PR-104 is a novel hypoxia-activated DNA cross-linking agent with marked activity against human tumor xenografts, both as monotherapy and combined with radiotherapy and chemotherapy.


Subject(s)
Antineoplastic Agents/pharmacology , DNA/chemistry , Hypoxia , Neoplasms/drug therapy , Nitrogen Mustard Compounds/pharmacology , Phosphates/pharmacology , Animals , Cell Line, Tumor , Comet Assay , Cross-Linking Reagents/pharmacology , DNA Damage , Drug Screening Assays, Antitumor , Histones/metabolism , Humans , Mice , Neoplasm Transplantation , Nitrogen Mustard Compounds/chemistry
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