12 results on '"David Broad"'
Search Results
2. Normal Values of High-resolution Transmural Perfusion Distribution Metrics for Automated Quantitative Pixel-wise Myocardial Perfusion Cardiovascular Magnetic Resonance
- Author
-
Christel Hermann Kamani, MD, Louise Brown, MD, PhD, Ioannis Botis, MD, MSc, Gaurav Gulsin, Sebastian Onciul, MD, David Broadbent, PhD, Alice Wood, MD, Christopher Saunderson, MD, Arka Das, MD, PhD, Nicholas Jex, MD, PhD, Amrit Chowdhary, PhD, Sharmaine Thirunavukarasu, PhD, Noor Sharrack, Kristopher Knott, PhD, Eylem Levelt, Peter Swoboda, Hui Xue, PhD, John P Greenwood, MD, PhD, James Moon, MD, Gerry McCann, Peter Kellman, PhD, and Sven Plein, MD, PhD
- Subjects
Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Published
- 2024
- Full Text
- View/download PDF
3. Resonant resurgent asymptotics from quantum field theory
- Author
-
Michael Borinsky and David Broadhurst
- Subjects
Nuclear and particle physics. Atomic energy. Radioactivity ,QC770-798 - Abstract
We perform an all-order resurgence analysis of a quantum field theory renormalon that contributes to an anomalous dimension in six-dimensional scalar ϕ3 theory and is governed by a third-order nonlinear differential equation. We augment the factorially divergent perturbative expansion associated to the renormalon by asymptotic expansions to all instanton orders, in a conjectured and well-tested formula. A distinctive feature of this renormalon singularity is the appearance of logarithmic terms, starting at second-instanton order in the trans-series. To highlight this and to illustrate our methods, we also analyze the trans-series for a closely related second-order nonlinear differential equation that exhibits a similarly resonant structure but lacks logarithmic contributions.
- Published
- 2022
- Full Text
- View/download PDF
4. In Vitro and In Vivo Analysis of Extracellular Vesicle‐Mediated Metastasis Using a Bright, Red‐Shifted Bioluminescent Reporter Protein
- Author
-
Gloria I. Perez, David Broadbent, Ahmed A. Zarea, Benedikt Dolgikh, Matthew P. Bernard, Alicia Withrow, Amelia McGill, Victoria Toomajian, Lukose K. Thampy, Jack Harkema, Joel R. Walker, Thomas A. Kirkland, Michael H. Bachmann, Jens Schmidt, and Masamitsu Kanada
- Subjects
autophagy ,biodistribution ,bioluminescence resonance energy transfer ,exosomes ,extracellular vesicles ,m/lEVs ,Genetics ,QH426-470 - Abstract
Abstract Cancer cells produce heterogeneous extracellular vesicles (EVs) as mediators of intercellular communication. This study focuses on a novel method to image EV subtypes and their biodistribution in vivo. A red‐shifted bioluminescence resonance energy transfer (BRET) EV reporter is developed, called PalmReNL, which allows for highly sensitive EV tracking in vitro and in vivo. PalmReNL enables the authors to study the common surface molecules across EV subtypes that determine EV organotropism and their functional differences in cancer progression. Regardless of injection routes, whether retro‐orbital or intraperitoneal, PalmReNL positive EVs, isolated from murine mammary carcinoma cells, localized to the lungs. The early appearance of metastatic foci in the lungs of mammary tumor‐bearing mice following multiple intraperitoneal injections of the medium and large EV (m/lEV)‐enriched fraction derived from mammary carcinoma cells is demonstrated. In addition, the results presented here show that tumor cell‐derived m/lEVs act on distant tissues through upregulating LC3 expression within the lung.
- Published
- 2022
- Full Text
- View/download PDF
5. Murine Model for Measuring Effects of Humanized-Dosing of Antibiotics on the Gut Microbiome
- Author
-
Shana R. Leopold, Kamilia Abdelraouf, David P. Nicolau, Hanako Agresta, Jethro Johnson, Kathleen Teter, Wm Michael Dunne, David Broadwell, Alex van Belkum, Lisa M. Schechter, Erica J. Sodergren, and George M. Weinstock
- Subjects
humanized antibiotic treatment ,piperacillin-tazobactam ,non-infected mouse model ,microbiome dynamics ,metabolome ,gastro-intestinal tract ,Microbiology ,QR1-502 - Abstract
There is a current need for enhancing our insight in the effects of antimicrobial treatment on the composition of human microbiota. Also, the spontaneous restoration of the microbiota after antimicrobial treatment requires better understanding. This is best addressed in well-defined animal models. We here present a model in which immune-competent or neutropenic mice were administered piperacillin-tazobactam (TZP) according to human treatment schedules. Before, during and after the TZP treatment, fecal specimens were longitudinally collected at established intervals over several weeks. Gut microbial taxonomic distribution and abundance were assessed through culture and molecular means during all periods. Non-targeted metabolomics analyses of stool samples using Quadrupole Time of Flight mass spectrometry (QTOF MS) were also applied to determine if a metabolic fingerprint correlated with antibiotic use, immune status, and microbial abundance. TZP treatment led to a 5–10-fold decrease in bacterial fecal viability counts which were not fully restored during post-antibiotic follow up. Two distinct, relatively uniform and reproducible restoration scenarios of microbiota changes were seen in post TZP-treatment mice. Post-antibiotic flora could consist of predominantly Firmicutes or, alternatively, a more diverse mix of taxa. In general, the pre-treatment microbial communities were not fully restored within the screening periods applied. A new species, closely related to Eubacterium siraeum, Mageeibacillus indolicus, and Saccharofermentans acetigenes, became predominant post-treatment in a significant proportion of mice, identified by 16S rRNA gene sequencing. Principal component analysis of QTOF MS of mouse feces successfully distinguished treated from non-treated mice as well as immunocompetent from neutropenic mice. We observe dynamic but distinct and reproducible responses in the mouse gut microbiota during and after TZP treatment and propose the current murine model as a useful tool for defining the more general post-antibiotic effects in the gastro-intestinal ecosystem where humanized antibiotic dosing may ultimately facilitate extrapolation to humans.
- Published
- 2022
- Full Text
- View/download PDF
6. Searching for a technology-driven acute rheumatic fever test: the START study protocol
- Author
-
David Broadhurst, Bo Remenyi, Timothy C Barnett, Jonathan R Carapetis, Jennifer Yan, Anna P Ralph, Glenn Pearson, Mark Mayo, Rachel Webb, Nicole J Moreland, Reuben McGregor, Anthony Bosco, Timo Lassmann, Rym Benothman, Julie Bennett, Nigel Wilson, and Tobias Kollmann
- Subjects
Medicine - Abstract
Introduction The absence of a diagnostic test for acute rheumatic fever (ARF) is a major impediment in managing this serious childhood condition. ARF is an autoimmune condition triggered by infection with group A Streptococcus. It is the precursor to rheumatic heart disease (RHD), a leading cause of health inequity and premature mortality for Indigenous peoples of Australia, New Zealand and internationally.Methods and analysis ‘Searching for a Technology-Driven Acute Rheumatic Fever Test’ (START) is a biomarker discovery study that aims to detect and test a biomarker signature that distinguishes ARF cases from non-ARF, and use systems biology and serology to better understand ARF pathogenesis. Eligible participants with ARF diagnosed by an expert clinical panel according to the 2015 Revised Jones Criteria, aged 5–30 years, will be recruited from three hospitals in Australia and New Zealand. Age, sex and ethnicity-matched individuals who are healthy or have non-ARF acute diagnoses or RHD, will be recruited as controls. In the discovery cohort, blood samples collected at baseline, and during convalescence in a subset, will be interrogated by comprehensive profiling to generate possible diagnostic biomarker signatures. A biomarker validation cohort will subsequently be used to test promising combinations of biomarkers. By defining the first biomarker signatures able to discriminate between ARF and other clinical conditions, the START study has the potential to transform the approach to ARF diagnosis and RHD prevention.Ethics and dissemination The study has approval from the Northern Territory Department of Health and Menzies School of Health Research ethics committee and the New Zealand Health and Disability Ethics Committee. It will be conducted according to ethical standards for research involving Indigenous Australians and New Zealand Māori and Pacific Peoples. Indigenous investigators and governance groups will provide oversight of study processes and advise on cultural matters.
- Published
- 2021
- Full Text
- View/download PDF
7. Data supporting development and validation of liquid chromatography tandem mass spectrometry method for the quantitative determination of bile acids in feces
- Author
-
Armaghan Shafaei, Joanna Rees, Claus T. Christophersen, Amanda Devine, David Broadhurst, and Mary C. Boyce
- Subjects
Bile acids ,Feces ,Extraction ,LC-MS/MS ,Stability ,Computer applications to medicine. Medical informatics ,R858-859.7 ,Science (General) ,Q1-390 - Abstract
Measuring bile acids in feces has an important role in disease prevention, diagnosis, treatment, and can be considered a measure of health status. Therefore, the primary aim was to develop a sensitive, robust, and high throughput liquid chromatography tandem mass spectrometry method with minimal sample preparation for quantitative determination of bile acids in human feces applicable to large cohorts. Due to the chemical diversity of bile acids, their wide concentration range in feces, and the complexity of feces itself, developing a sensitive and selective analytical method for bile acids is challenging. A simple extraction method using methanol suitable for subsequent quantification by liquid chromatography tandem mass spectrometry has been reported in, “Extraction and quantitative determination of bile acids in feces” [1]. The data highlight the importance of optimization of the extraction procedure and the stability of the bile acids in feces post-extraction and prior to analysis and after several freeze-thaw cycles.
- Published
- 2021
- Full Text
- View/download PDF
8. Evidence for a functional interaction of WNT10A and EBF1 in male-pattern baldness.
- Author
-
Lara M Hochfeld, Marta Bertolini, David Broadley, Natalia V Botchkareva, Regina C Betz, Susanne Schoch, Markus M Nöthen, and Stefanie Heilmann-Heimbach
- Subjects
Medicine ,Science - Abstract
More than 300 genetic risk loci have been identified for male pattern baldness (MPB) but little is known about the exact molecular mechanisms through which the associated variants exert their effects on MPB pathophysiology. Here, we aimed at further elucidating the regulatory architecture of the MPB risk locus on chromosome (chr.) 2q35, where we have previously reported a regulatory effect of the MPB lead variant on the expression of WNT10A. A HaploReg database research for regulatory annotations revealed that the association signal at 2q35 maps to a binding site for the transcription factor EBF1, whose gene is located at a second MPB risk locus on chr. 5q33.3. To investigate a potential interaction between EBF1 and WNT10A during MPB development, we performed in vitro luciferase reporter assays as well as expression analyses and immunofluorescence co-stainings in microdissected human hair follicles. Our experiments confirm that EBF1 activates the WNT10A promoter and that the WNT10A/EBF1 interaction is impacted by the allelic expression of the MPB risk allele at 2q35. Expression analyses across different hair cycle phases and immunhistochemical (co)stainings against WNT10A and EBF1 suggest a predominant relevance of EBF1/WNT10A interaction for hair shaft formation during anagen. Based on these findings we suggest a functional mechanism at the 2q35 risk locus for MPB, where an MPB-risk allele associated reduction in WNT10A promoter activation via EBF1 results in a decrease in WNT10A expression that eventually results in anagen shortening, that is frequently observed in MPB affected hair follicles. To our knowledge, this study is the first follow-up study on MPB that proves functional interaction between two MPB risk loci and sheds light on the underlying pathophysiological mechanism at these loci.
- Published
- 2021
- Full Text
- View/download PDF
9. A versatile oblique plane microscope for large-scale and high-resolution imaging of subcellular dynamics
- Author
-
Etai Sapoznik, Bo-Jui Chang, Jaewon Huh, Robert J Ju, Evgenia V Azarova, Theresa Pohlkamp, Erik S Welf, David Broadbent, Alexandre F Carisey, Samantha J Stehbens, Kyung-Min Lee, Arnaldo Marín, Ariella B Hanker, Jens C Schmidt, Carlos L Arteaga, Bin Yang, Yoshihiko Kobayashi, Purushothama Rao Tata, Rory Kruithoff, Konstantin Doubrovinski, Douglas P Shepherd, Alfred Millett-Sikking, Andrew G York, Kevin M Dean, and Reto P Fiolka
- Subjects
fluorescence ,microscopy ,light-sheet ,optogenetics ,microfluidics ,particle tracking ,Medicine ,Science ,Biology (General) ,QH301-705.5 - Abstract
We present an oblique plane microscope (OPM) that uses a bespoke glass-tipped tertiary objective to improve the resolution, field of view, and usability over previous variants. Owing to its high numerical aperture optics, this microscope achieves lateral and axial resolutions that are comparable to the square illumination mode of lattice light-sheet microscopy, but in a user friendly and versatile format. Given this performance, we demonstrate high-resolution imaging of clathrin-mediated endocytosis, vimentin, the endoplasmic reticulum, membrane dynamics, and Natural Killer-mediated cytotoxicity. Furthermore, we image biological phenomena that would be otherwise challenging or impossible to perform in a traditional light-sheet microscope geometry, including cell migration through confined spaces within a microfluidic device, subcellular photoactivation of Rac1, diffusion of cytoplasmic rheological tracers at a volumetric rate of 14 Hz, and large field of view imaging of neurons, developing embryos, and centimeter-scale tissue sections.
- Published
- 2020
- Full Text
- View/download PDF
10. Study protocol for the safety and efficacy of probiotic therapy on days alive and out of hospital in adult ICU patients: the multicentre, randomised, placebo-controlled Restoration Of gut microflora in Critical Illness Trial (ROCIT)
- Author
-
Tobias Strunk, David Broadhurst, Edward Litton, Anu Rammohan, Edward Raby, Laurens Manning, Matthew Anstey, Andy R Chapman, Andrew Currie, Janet Ferrier, Joel Gummer, Alisa Higgins, Jolene Lim, Erina Myers, Katrina Orr, Anne-Marie Palermo, Andrew Paparini, Susan Pellicano, Adrian Regli, Bernhard Richter, Sam Salman, Sharon Waterson, Brad Wibrow, and Fiona M Wood
- Subjects
Medicine - Abstract
Introduction The effect of early and sustained administration of daily probiotic therapy on patients admitted to the intensive care unit (ICU) remains uncertain.Methods and analysis The Restoration Of gut microflora in Critical Illness Trial (ROCIT) study is a multicentre, randomised, placebo-controlled, parallel-group, two-sided superiority trial that will enrol 220 patients in five ICUs. Adult patients who are within 48 hours of admission to an ICU and are expected to require intensive care beyond the next calendar day will be randomised in a 1:1 ratio to receive early and sustained Lactobacillus plantarum 299v probiotic therapy in addition to usual care or placebo in addition to usual care. The primary endpoint is days alive and out of hospital to day 60.Ethics and dissemination ROCIT has been approved by the South Metropolitan Health Service Human Research Ethics Committee (ref: RGS00000004) and the St John of God Health Care Human Research Ethics Committee (ref: 1183). The trial results will be submitted for publication in a peer-reviewed journal.Trial registration number Australian and New Zealand Clinical Trials Registry (ANZCTR12617000783325); Pre-results.
- Published
- 2020
- Full Text
- View/download PDF
11. Exploring a Role for Regulatory miRNAs In Wound Healing during Ageing:Involvement of miR-200c in wound repair
- Author
-
Eerik Aunin, David Broadley, Mohammed I. Ahmed, Andrei N. Mardaryev, and Natalia V. Botchkareva
- Subjects
Medicine ,Science - Abstract
Abstract Multiple factors and conditions can lead to impaired wound healing. Chronic non-healing wounds are a common problem among the elderly. To identify microRNAs negatively impacting the wound repair, global miRNA profiling of wounds collected from young and old mice was performed. A subset of miRNAs that exhibited an age-dependent expression pattern during wound closure was identified, including miR-31 and miR-200c. The expression of miR-200 family members was markedly downregulated upon wounding in both young and aged mice, with an exception of acute upregulation of miR-200c at the early phase of wound healing in aged skin. In unwounded aged skin (versus unwounded younger skin), the level of miR-200c was also found elevated in both human and mice. Overexpression of miR-200c in human ex vivo wounds delayed re-epithelialisation and inhibited cell proliferation in the wound epithelium. Modulation of miR-200c expression in both human and mouse keratinocytes in vitro revealed inhibitory effects of miR-200c on migration, but not proliferation. Accelerated wound closure in vitro induced by anti-miR-200c was associated with upregulation of genes controlling cell migration. Thus, our study identified miR-200c as a critical determinant that inhibits cell migration during skin repair after injury and may contribute to age-associated alterations in wound repair.
- Published
- 2017
- Full Text
- View/download PDF
12. 'Notame': Workflow for Non-Targeted LC–MS Metabolic Profiling
- Author
-
Anton Klåvus, Marietta Kokla, Stefania Noerman, Ville M. Koistinen, Marjo Tuomainen, Iman Zarei, Topi Meuronen, Merja R. Häkkinen, Soile Rummukainen, Ambrin Farizah Babu, Taisa Sallinen, Olli Kärkkäinen, Jussi Paananen, David Broadhurst, Carl Brunius, and Kati Hanhineva
- Subjects
metabolomics ,LC–MS ,mass spectrometry ,metabolic profiling ,computational statistical ,unsupervised learning ,Microbiology ,QR1-502 - Abstract
Metabolomics analysis generates vast arrays of data, necessitating comprehensive workflows involving expertise in analytics, biochemistry and bioinformatics in order to provide coherent and high-quality data that enable discovery of robust and biologically significant metabolic findings. In this protocol article, we introduce notame, an analytical workflow for non-targeted metabolic profiling approaches, utilizing liquid chromatography–mass spectrometry analysis. We provide an overview of lab protocols and statistical methods that we commonly practice for the analysis of nutritional metabolomics data. The paper is divided into three main sections: the first and second sections introducing the background and the study designs available for metabolomics research and the third section describing in detail the steps of the main methods and protocols used to produce, preprocess and statistically analyze metabolomics data and, finally, to identify and interpret the compounds that have emerged as interesting.
- Published
- 2020
- Full Text
- View/download PDF
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.