479 results on '"Lee TR"'
Search Results
2. Characterisation and natural progression of SARS-CoV-2 infection in ferrets
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Gough G. Au, Glenn A. Marsh, Alexander J. McAuley, Suzanne Lowther, Lee Trinidad, Sarah Edwards, Shawn Todd, Jennifer Barr, Matthew P. Bruce, Timothy B. Poole, Sheree Brown, Rachel Layton, Sarah Riddell, Brenton Rowe, Elisha Soldani, Willy W. Suen, Jemma Bergfeld, John Bingham, Jean Payne, Peter A. Durr, Trevor W. Drew, and Seshadri S. Vasan
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Medicine ,Science - Abstract
Abstract Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is responsible for the infectious disease COVID-19, which has rapidly become an international pandemic with significant impact on healthcare systems and the global economy. To assist antiviral therapy and vaccine development efforts, we performed a natural history/time course study of SARS-CoV-2 infection in ferrets to characterise and assess the suitability of this animal model. Ten ferrets of each sex were challenged intranasally with 4.64 × 104 TCID50 of SARS-CoV-2 isolate Australia/VIC01/2020 and monitored for clinical disease signs, viral shedding, and tissues collected post-mortem for histopathological and virological assessment at set intervals. We found that SARS-CoV-2 replicated in the upper respiratory tract of ferrets with consistent viral shedding in nasal wash samples and oral swab samples up until day 9. Infectious SARS-CoV-2 was recovered from nasal washes, oral swabs, nasal turbinates, pharynx, and olfactory bulb samples within 3–7 days post-challenge; however, only viral RNA was detected by qRT-PCR in samples collected from the trachea, lung, and parts of the gastrointestinal tract. Viral antigen was seen exclusively in nasal epithelium and associated sloughed cells and draining lymph nodes upon immunohistochemical staining. Due to the absence of clinical signs after viral challenge, our ferret model is appropriate for studying asymptomatic SARS-CoV-2 infections and most suitable for use in vaccine efficacy studies.
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- 2022
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3. Long range synchronization within the enteric nervous system underlies propulsion along the large intestine in mice
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Nick J. Spencer, Lee Travis, Lukasz Wiklendt, Marcello Costa, Timothy J. Hibberd, Simon J. Brookes, Phil Dinning, Hongzhen Hu, David A. Wattchow, and Julian Sorensen
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Biology (General) ,QH301-705.5 - Abstract
Nick Spencer et al. made simultaneous multi-site electrophysiological recordings with video imaging of colonic wall movements from ex vivo mouse colon, in order to correlate propulsion of content with underlying electrical signals from the smooth muscle. Their results demonstrate that excitatory and inhibitory junction potentials are synchronized in both the proximal and distal colon, suggesting that the enteric nervous system network communicates over a longer range than previously expected.
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- 2021
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4. Anatomical distribution of CGRP-containing lumbosacral spinal afferent neurons in the mouse uterine horn
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Kelsi N. Dodds, Melinda A. Kyloh, Lee Travis, Mack Cox, Tim J. Hibberd, and Nick J. Spencer
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uterus ,pain ,CGRP ,sensory innervation ,spinal ganglia ,Neurosciences. Biological psychiatry. Neuropsychiatry ,RC321-571 - Abstract
Sensory stimuli from the uterus are detected by spinal afferent neurons whose cell bodies arise from thoracolumbar and lumbosacral dorsal root ganglia (DRG). Using an in vivo survival surgical technique developed in our laboratory to remove select DRG from live mice, we recently quantified the topographical distribution of thoracolumbar spinal afferents innervating the mouse uterine horn, revealed by loss of immunoreactivity to calcitonin gene-related peptide (CGRP). Here, we used the same technique to investigate the distribution of lumbosacral uterine spinal afferents, in which L5-S1 DRG were unilaterally removed from adult female C57BL/6J mice (N = 6). Following 10–12 days recovery, CGRP immunoreactivity was quantified along the length of uterine horns using fluorescence immunohistochemistry. Relative to myometrial thickness, overall CGRP density in uterine tissues ipsilateral to L5-S1 DRG removal was reduced compared to the DRG-intact, contralateral side (P = 0.0265). Regionally, however, myometrial CGRP density was unchanged in the cranial, mid, and caudal portions. Similarly, CGRP-expressing nerve fiber counts, network lengths, junctions, and the proportion of area occupied by CGRP immunoreactivity were unaffected by DRG removal (P ≥ 0.2438). Retrograde neuronal tracing from the caudal uterine horn revealed fewer spinal afferents here arise from lumbosacral than thoracolumbar DRG (P = 0.0442) (N = 4). These data indicate that, unlike thoracolumbar DRG, lumbosacral spinal afferent nerves supply relatively modest sensory innervation across the mouse uterine horn, with no regional specificity. We conclude most sensory information between the mouse uterine horn and central nervous system is likely relayed via thoracolumbar spinal afferents.
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- 2022
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5. ChAdOx1 nCoV-19 (AZD1222) vaccine candidate significantly reduces SARS-CoV-2 shedding in ferrets
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Glenn A. Marsh, Alexander J. McAuley, Gough G. Au, Sarah Riddell, Daniel Layton, Nagendrakumar B. Singanallur, Rachel Layton, Jean Payne, Peter A. Durr, Hannah Bender, Jennifer A. Barr, John Bingham, Victoria Boyd, Sheree Brown, Matthew P. Bruce, Kathie Burkett, Teresa Eastwood, Sarah Edwards, Tamara Gough, Kim Halpin, Jenni Harper, Clare Holmes, William S. J. Horman, Petrus Jansen van Vuren, Suzanne Lowther, Kate Maynard, Kristen D. McAuley, Matthew J. Neave, Timothy Poole, Christina Rootes, Brenton Rowe, Elisha Soldani, Vittoria Stevens, Cameron R. Stewart, Willy W. Suen, Mary Tachedjian, Shawn Todd, Lee Trinidad, Duane Walter, Naomi Watson, Trevor W. Drew, Sarah C. Gilbert, Teresa Lambe, and S. S. Vasan
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Immunologic diseases. Allergy ,RC581-607 ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
Abstract Vaccines against SARS-CoV-2 are likely to be critical in the management of the ongoing pandemic. A number of candidates are in Phase III human clinical trials, including ChAdOx1 nCoV-19 (AZD1222), a replication-deficient chimpanzee adenovirus-vectored vaccine candidate. In preclinical trials, the efficacy of ChAdOx1 nCoV-19 against SARS-CoV-2 challenge was evaluated in a ferret model of infection. Groups of ferrets received either prime-only or prime-boost administration of ChAdOx1 nCoV-19 via the intramuscular or intranasal route. All ChAdOx1 nCoV-19 administration combinations resulted in significant reductions in viral loads in nasal-wash and oral swab samples. No vaccine-associated adverse events were observed associated with the ChAdOx1 nCoV-19 candidate, with the data from this study suggesting it could be an effective and safe vaccine against COVID-19. Our study also indicates the potential for intranasal administration as a way to further improve the efficacy of this leading vaccine candidate.
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- 2021
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6. Modification of Neurogenic Colonic Motor Behaviours by Chemogenetic Ablation of Calretinin Neurons
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Jing Feng, Tim J. Hibberd, Jialie Luo, Pu Yang, Zili Xie, Lee Travis, Nick J. Spencer, and Hongzhen Hu
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colonic motor complex ,IPAN ,enteric nervous system ,large intestine ,colon ,sensory neuron ,Neurosciences. Biological psychiatry. Neuropsychiatry ,RC321-571 - Abstract
How the enteric nervous system determines the pacing and propagation direction of neurogenic contractions along the colon remains largely unknown. We used a chemogenetic strategy to ablate enteric neurons expressing calretinin (CAL). Mice expressing human diphtheria toxin receptor (DTR) in CAL neurons were generated by crossing CAL-ires-Cre mice with Cre-dependent ROSA26-DTR mice. Immunohistochemical analysis revealed treatment with diphtheria toxin incurred a 42% reduction in counts of Hu-expressing colonic myenteric neurons (P = 0.036), and 57% loss of CAL neurons (comprising ∼25% of all Hu neurons; P = 0.004) compared to control. As proportions of Hu-expressing neurons, CAL neurons that contained nitric oxide synthase (NOS) were relatively spared (control: 15 ± 2%, CAL-DTR: 13 ± 1%; P = 0.145), while calretinin neurons lacking NOS were significantly reduced (control: 26 ± 2%, CAL-DTR: 18 ± 5%; P = 0.010). Colonic length and pellet sizes were significantly reduced without overt inflammation or changes in ganglionic density. Interestingly, colonic motor complexes (CMCs) persisted with increased frequency (mid-colon interval 111 ± 19 vs. 189 ± 24 s, CAL-DTR vs. control, respectively, P < 0.001), decreased contraction size (mid-colon AUC 26 ± 24 vs. 59 ± 13 gram/seconds, CAL-DTR vs. control, respectively, P < 0.001), and lacked preferential anterograde migration (P < 0.001). The functional effects of modest calretinin neuron ablation, particularly increased neurogenic motor activity frequencies, differ from models that incur general enteric neuron loss, and suggest calretinin neurons may contribute to pacing, force, and polarity of CMCs in the large bowel.
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- 2022
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7. Lack of Increase in Muscle Mitochondrial Protein Synthesis During the Course of Aerobic Exercise and Its Recovery in the Fasting State Irrespective of Obesity
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Nathan Serrano, Lee Tran, Nyssa Hoffman, Lori Roust, Elena A. De Filippis, Chad C. Carroll, Shivam H. Patel, Katon A. Kras, Matthew Buras, and Christos S. Katsanos
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exercise ,mitochondria ,protein synthesis ,PGC-1α ,myosin heavy chain ,Physiology ,QP1-981 - Abstract
Acute aerobic exercise induces skeletal muscle mitochondrial gene expression, which in turn can increase muscle mitochondrial protein synthesis. In this regard, the peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α), is a master regulator of mitochondrial biogenesis, and thus mitochondrial protein synthesis. However, PGC-1α expression is impaired in muscle of humans with obesity in response to acute aerobic exercise. Therefore, we sought to determine whether muscle mitochondrial protein synthesis is also impaired under the same conditions in humans with obesity. To this end, we measured mitochondrial and mixed-muscle protein synthesis in skeletal muscle of untrained subjects with (body fat: 34.7 ± 2.3%) and without (body fat: 25.3 ± 3.3%) obesity in a basal period and during a continuous period that included a 45 min cycling exercise (performed at an intensity corresponding to 65% of heart rate reserve) and a 3-h post-exercise recovery. Exercise increased PGC-1α mRNA expression in muscle of subjects without obesity, but not in subjects with obesity. However, muscle mitochondrial protein synthesis did not increase in either subject group. Similarly, mixed-muscle protein synthesis did not increase in either group. Concentrations of plasma amino acids decreased post-exercise in the subjects without obesity, but not in the subjects with obesity. We conclude that neither mitochondrial nor mixed-muscle protein synthesis increase in muscle of humans during the course of a session of aerobic exercise and its recovery period in the fasting state irrespective of obesity.Trial Registration: The study has been registered within ClinicalTrials.gov (NCT01824173).
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- 2021
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8. A Novel Method for Electrophysiological Analysis of EMG Signals Using MesaClip
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Lukasz Wiklendt, Simon J. H. Brookes, Marcello Costa, Lee Travis, Nick J. Spencer, and Phil G. Dinning
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artifact removal ,non-harmonic model ,action potential ,wavelet transform ,time-frequency analysis ,Physiology ,QP1-981 - Abstract
In electrophysiology, many methods have been proposed for the analysis of action potential firing frequencies. The aim of this study was to present an algorithm developed for a continuous wavelet transform that enables the filtering out of frequencies contributing to the shapes of action potentials (spikes), whilst retaining the frequencies that encode the periodicity of spike trains. The continuous wavelet transform allows us to decompose a signal into its constituent frequencies. A signal with a single event, such as a spike, is composed of frequencies that characterize the shape of the spike. A signal with two spikes will also be composed of frequencies characterizing the shape of the action potential, but in addition will include a substantial portion of its power at the frequency corresponding to the time-difference between the two spikes. This is achieved by clipping peaks from the wavelet amplitudes that are narrower than a given minimum number of phase cycles. We present some application examples in both synthetic signals and electrophysiological recordings. This new approach can provide a major new analytical tool for analysis of electrophysiological signals.
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- 2020
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9. Recurrent WNT pathway alterations are frequent in relapsed small cell lung cancer
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Alex H. Wagner, Siddhartha Devarakonda, Zachary L. Skidmore, Kilannin Krysiak, Avinash Ramu, Lee Trani, Jason Kunisaki, Ashiq Masood, Saiama N. Waqar, Nicholas C. Spies, Daniel Morgensztern, Jason Waligorski, Jennifer Ponce, Robert S. Fulton, Leonard B. Maggi, Jason D. Weber, Mark A. Watson, Christopher J. O’Conor, Jon H. Ritter, Rachelle R. Olsen, Haixia Cheng, Anandaroop Mukhopadhyay, Ismail Can, Melissa H. Cessna, Trudy G. Oliver, Elaine R. Mardis, Richard K. Wilson, Malachi Griffith, Obi L. Griffith, and Ramaswamy Govindan
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Science - Abstract
Small cell lung cancer (SCLC) patients frequently relapse and become resistant to chemotherapy. Here, the authors analyse the genomic and transcriptomic landscape of primary and relapsed SCLC patients as well as in vitro models, and discover that activation of WNT signalling can drive chemotherapy resistance.
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- 2018
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10. Enzyme intermediates captured 'on the fly' by mix-and-inject serial crystallography
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Jose L. Olmos, Suraj Pandey, Jose M. Martin-Garcia, George Calvey, Andrea Katz, Juraj Knoska, Christopher Kupitz, Mark S. Hunter, Mengning Liang, Dominik Oberthuer, Oleksandr Yefanov, Max Wiedorn, Michael Heyman, Mark Holl, Kanupriya Pande, Anton Barty, Mitchell D. Miller, Stephan Stern, Shatabdi Roy-Chowdhury, Jesse Coe, Nirupa Nagaratnam, James Zook, Jacob Verburgt, Tyler Norwood, Ishwor Poudyal, David Xu, Jason Koglin, Matthew H. Seaberg, Yun Zhao, Saša Bajt, Thomas Grant, Valerio Mariani, Garrett Nelson, Ganesh Subramanian, Euiyoung Bae, Raimund Fromme, Russell Fung, Peter Schwander, Matthias Frank, Thomas A. White, Uwe Weierstall, Nadia Zatsepin, John Spence, Petra Fromme, Henry N. Chapman, Lois Pollack, Lee Tremblay, Abbas Ourmazd, George N. Phillips, and Marius Schmidt
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Biology (General) ,QH301-705.5 - Abstract
Abstract Background Ever since the first atomic structure of an enzyme was solved, the discovery of the mechanism and dynamics of reactions catalyzed by biomolecules has been the key goal for the understanding of the molecular processes that drive life on earth. Despite a large number of successful methods for trapping reaction intermediates, the direct observation of an ongoing reaction has been possible only in rare and exceptional cases. Results Here, we demonstrate a general method for capturing enzyme catalysis “in action” by mix-and-inject serial crystallography (MISC). Specifically, we follow the catalytic reaction of the Mycobacterium tuberculosis β-lactamase with the third-generation antibiotic ceftriaxone by time-resolved serial femtosecond crystallography. The results reveal, in near atomic detail, antibiotic cleavage and inactivation from 30 ms to 2 s. Conclusions MISC is a versatile and generally applicable method to investigate reactions of biological macromolecules, some of which are of immense biological significance and might be, in addition, important targets for structure-based drug design. With megahertz X-ray pulse rates expected at the Linac Coherent Light Source II and the European X-ray free-electron laser, multiple, finely spaced time delays can be collected rapidly, allowing a comprehensive description of biomolecular reactions in terms of structure and kinetics from the same set of X-ray data.
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- 2018
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11. Positive regulation of hepatic carnitine palmitoyl transferase 1A (CPT1A) activities by soy isoflavones and L-carnitine.
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Shin ES, Cho SY, Lee EH, Lee SJ, Chang IS, and Lee TR
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BACKGROUND: Genistein increases CPT1A, a rate-limiting enzyme in the beta-oxidation pathway, enzyme activity by increasing CPT1A transcription in HepG2 cells and, consequently, suppresses high fat induced obesity in C57BL/6J mice. Genistein and daidzein are the most abundant isoflavones in soy.AIM OF STUDY: To investigate the effect of co-treatment of genistein and L-carnitine on CPT1A enzyme activity and to determine whether daidzein also increases CPT1A activity and to establish a cell line that can be used to screen chemicals to regulate CPT1A transcription.METHODS: The enzyme activities of CPT1A were determined after HepG2 cells were incubated with 10muM genistein or 10muM daidzein or 1 mM L-carnitine or in combination with 10muM genistein and 1 mM L-carnitine or in combination with 10muM daidzein and 1 mM L-carnitine. The mRNA expression levels of CPT1A were determined by real time PCR method after HepG2 cells were incubated with 10muM genistein or 10muM daidzein. A suggested CPT1A promoter region was cloned from human genomic DNA and the CPT1A promoter-luciferase reporter gene construct was made, and the promoter-reporter gene construct was transfected into human hepatoma cell line Huh7.RESULTS: The enzyme activity of CPT1A was at least 2.3- fold higher in L-carnitine and genistein co-treated HepG2 cells than either single-agent treated cells. Daidzein also significantly increased the mRNA expression of CPT1A as well as the enzyme activity of CPT1A. A stable Huh7 cell line, which was selected after Huh7 cells were transfected with CPT1A promoter luciferase reporter gene construct, was characterized by confirming that luciferase activity of the cell line can be regulated by genistein and daidzein as well as clofibrate, a well-known CPT1A mRNA up-regulating drug.CONCLUSIONS: Genistein and daidzein can up-regulate CPT1A enzyme activity through up-regulation of CPT1A transcription. Co-treatment of L-carnitine and genistein additively increases CPT1A enzyme activity in HepG2 cells. A stable Huh7 cell line transfected with the CPT1A promoter luciferase reporter gene was established and characterized. [ABSTRACT FROM AUTHOR]
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- 2006
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12. Zika vector transmission risk in temperate Australia: a vector competence study
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Jean-Bernard Duchemin, Peter T. Mee, Stacey E. Lynch, Ravikiran Vedururu, Lee Trinidad, and Prasad Paradkar
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Zika virus ,Vector competence ,Aedes aegypti ,Aedes albopictus ,Culex quinquefasciatus ,Aedes notoscriptus ,Infectious and parasitic diseases ,RC109-216 - Abstract
Abstract Background Zika virus is an emerging pathogen of global importance. It has been responsible for recent outbreaks in the Americas and in the Pacific region. This study assessed five different mosquito species from the temperate climatic zone in Australia and included Aedes albopictus as a potentially invasive species. Methods Mosquitoes were orally challenged by membrane feeding with Zika virus strain of Cambodia 2010 origin, belonging to the Asian clade. Virus infection and dissemination were assessed by quantitative PCR on midgut and carcass after dissection. Transmission was assessed by determination of cytopathogenic effect of saliva (CPE) on Vero cells, followed by determination of 50% tissue culture infectious dose (TCID50) for CPE positive samples. Additionally, the presence of Wolbachia endosymbiont infection was assessed by qPCR and standard PCR. Results Culex mosquitoes were found unable to present Zika virus in saliva, as demonstrated by molecular as well as virological methods. Aedes aegypti, was used as a positive control for Zika infection and showed a high level of virus infection, dissemination and transmission. Local Aedes species, Ae. notoscriptus and, to a lesser degree, Ae. camptorhynchus were found to expel virus in their saliva and contained viral nucleic acid within the midgut. Molecular assessment identified low or no dissemination for these species, possibly due to low virus loads. Ae. albopictus from Torres Strait islands origin was shown as an efficient vector. Cx quinquefasciatus was shown to harbour Wolbachia endosymbionts at high prevalence, whilst no Wolbachia was found in Cx annulirostris. The Australian Ae. albopictus population was shown to harbour Wolbachia at high frequency. Conclusions The risk of local Aedes species triggering large Zika epidemics in the southern parts of Australia is low. The potentially invasive Ae. albopictus showed high prevalence of virus in the saliva and constitutes a potential threat if this mosquito species becomes established in mainland Australia. Complete risk analysis of Zika transmission in the temperate zone would require an assessment of the impact of temperature on Zika virus replication within local and invasive mosquito species.
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- 2017
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13. Index
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Gloria L. Cronin and Lee Trepanier
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- 2013
14. Contributors
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Gloria L. Cronin and Lee Trepanier
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- 2013
15. Saul Bellow's Politics: A Selected Annotated Bibliography, 1947-Present
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Gloria L. Cronin and Lee Trepanier
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- 2013
16. 9. Our Father's Politics: Gregory, Adam, and Daniel Bellow
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Gloria L. Cronin and Lee Trepanier
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- 2013
17. 8. Biography, Elegy, and the Politics of Modernity in Saul Bellow's Ravelstein
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Gloria L. Cronin and Lee Trepanier
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- 2013
18. 5. The Jewish Atlantic—The Deployment of Blackness in Saul Bellow
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Gloria L. Cronin and Lee Trepanier
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- 2013
19. 7. Mr. Sammler's Planet: Saul Bellow’s 1968 Speech at San Francisco State University
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Gloria L. Cronin and Lee Trepanier
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- 2013
20. 6. Washed Up on the Shores of Truth: Saul Bellow’s Post-Holocaust America
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Gloria L. Cronin and Lee Trepanier
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- 2013
21. Series Foreword
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Gloria L. Cronin and Lee Trepanier
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- 2013
22. 1. Trotskyism in the Early Work of Saul Bellow
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Gloria L. Cronin and Lee Trepanier
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- 2013
23. 4. The Politics of Art: The Colonial Library Meets the Carnivalesque in Henderson the Rain King
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Gloria L. Cronin and Lee Trepanier
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- 2013
24. 3. Saul Bellow and the Absent Woman Syndrome: Traces of India in “Leaving the Yellow House
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Gloria L. Cronin and Lee Trepanier
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- 2013
25. 2. Bellow as Jew and Jewish Writer
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Gloria L. Cronin and Lee Trepanier
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- 2013
26. Front cover
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Gloria L. Cronin and Lee Trepanier
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- 2013
27. Truncating Prolactin Receptor Mutations Promote Tumor Growth in Murine Estrogen Receptor-Alpha Mammary Carcinomas
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Obi L. Griffith, Szeman Ruby Chan, Malachi Griffith, Kilannin Krysiak, Zachary L. Skidmore, Jasreet Hundal, Julie A. Allen, Cora D. Arthur, Daniele Runci, Mattia Bugatti, Alexander P. Miceli, Heather Schmidt, Lee Trani, Krishna-Latha Kanchi, Christopher A. Miller, David E. Larson, Robert S. Fulton, William Vermi, Richard K. Wilson, Robert D. Schreiber, and Elaine R. Mardis
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breast cancer ,estrogen-receptor positive ,luminal ,STAT1 ,mouse model ,whole genome sequencing ,PRLR ,Biology (General) ,QH301-705.5 - Abstract
Estrogen receptor alpha-positive (ERα+) luminal tumors are the most frequent subtype of breast cancer. Stat1−/− mice develop mammary tumors that closely recapitulate the biological characteristics of this cancer subtype. To identify transforming events that contribute to tumorigenesis, we performed whole genome sequencing of Stat1−/− primary mammary tumors and matched normal tissues. This investigation identified somatic truncating mutations affecting the prolactin receptor (PRLR) in all tumor and no normal samples. Targeted sequencing confirmed the presence of these mutations in precancerous lesions, indicating that this is an early event in tumorigenesis. Functional evaluation of these heterozygous mutations in Stat1−/− mouse embryonic fibroblasts showed that co-expression of truncated and wild-type PRLR led to aberrant STAT3 and STAT5 activation downstream of the receptor, cellular transformation in vitro, and tumor formation in vivo. In conclusion, truncating mutations of PRLR promote tumor growth in a model of human ERα+ breast cancer and warrant further investigation.
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- 2016
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28. The impressions of a sample of British and overseas student nurses of some social aspects of their training.
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Clarke M and Lee TR
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NURSES , *EDUCATION , *NURSING , *SICK people , *MEDICAL care , *CIVILIZATION - Abstract
As part of a larger study, female student nurses from overseas and Britain in four training schools for the general nursing register were interviewed to obtain their perceptions of their reception at the hospital. their later welfare, and some of their general reactions to their training. Differences between the British and overseas student nurses were mainly related to experience before training and their reception at the hospital. Many similarities between the two groups were also found with respect to their later experiences and attitudes toward nursing. A proportion of the overseas students had experienced expressions of racial prejudice from patients. [ABSTRACT FROM AUTHOR]
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- 1976
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29. Structural enzymology using X-ray free electron lasers
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Christopher Kupitz, Jose L. Olmos Jr., Mark Holl, Lee Tremblay, Kanupriya Pande, Suraj Pandey, Dominik Oberthür, Mark Hunter, Mengning Liang, Andrew Aquila, Jason Tenboer, George Calvey, Andrea Katz, Yujie Chen, Max O. Wiedorn, Juraj Knoska, Alke Meents, Valerio Majriani, Tyler Norwood, Ishwor Poudyal, Thomas Grant, Mitchell D. Miller, Weijun Xu, Aleksandra Tolstikova, Andrew Morgan, Markus Metz, Jose M. Martin-Garcia, James D. Zook, Shatabdi Roy-Chowdhury, Jesse Coe, Nirupa Nagaratnam, Domingo Meza, Raimund Fromme, Shibom Basu, Matthias Frank, Thomas White, Anton Barty, Sasa Bajt, Oleksandr Yefanov, Henry N. Chapman, Nadia Zatsepin, Garrett Nelson, Uwe Weierstall, John Spence, Peter Schwander, Lois Pollack, Petra Fromme, Abbas Ourmazd, George N. Phillips Jr., and Marius Schmidt
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Crystallography ,QD901-999 - Abstract
Mix-and-inject serial crystallography (MISC) is a technique designed to image enzyme catalyzed reactions in which small protein crystals are mixed with a substrate just prior to being probed by an X-ray pulse. This approach offers several advantages over flow cell studies. It provides (i) room temperature structures at near atomic resolution, (ii) time resolution ranging from microseconds to seconds, and (iii) convenient reaction initiation. It outruns radiation damage by using femtosecond X-ray pulses allowing damage and chemistry to be separated. Here, we demonstrate that MISC is feasible at an X-ray free electron laser by studying the reaction of M. tuberculosis ß-lactamase microcrystals with ceftriaxone antibiotic solution. Electron density maps of the apo-ß-lactamase and of the ceftriaxone bound form were obtained at 2.8 Å and 2.4 Å resolution, respectively. These results pave the way to study cyclic and non-cyclic reactions and represent a new field of time-resolved structural dynamics for numerous substrate-triggered biological reactions.
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- 2017
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30. Inclusion of trans-resveratrol in methylated cyclodextrins: synthesis and solid-state structures
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Lee Trollope, Dyanne L. Cruickshank, Terence Noonan, Susan A. Bourne, Milena Sorrenti, Laura Catenacci, and Mino R. Caira
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cyclodextrin ,inclusion complexes ,thermal analysis ,trans-resveratrol ,X-ray structures ,Science ,Organic chemistry ,QD241-441 - Abstract
The phytoalexin trans-resveratrol, 5-[(1E)-2-(4-hydroxyphenyl)ethenyl]-1,3-benzenediol, is a well-known, potent antioxidant having a variety of possible biomedical applications. However, its adverse physicochemical properties (low stability, poor aqueous solubility) limit such applications and its inclusion in cyclodextrins (CDs) has potential for addressing these shortcomings. Here, various methods of the attempted synthesis of inclusion complexes between trans-resveratrol and three methylated cyclodextrins (permethylated α-CD, permethylated β-CD and 2,6-dimethylated β-CD) are described. Isolation of the corresponding crystalline 1:1 inclusion compounds enabled their full structure determination by X-ray analysis for the first time, revealing a variety of guest inclusion modes and unique supramolecular crystal packing motifs. The three crystalline inclusion complexes were also fully characterized by thermal analysis (hot stage microscopy, thermogravimetric analysis and differential scanning calorimetry). To complement the solid-state data, phase-solubility studies were conducted using a series of CDs (native and variously derivatised) to establish their effect on the aqueous solubility of trans-resveratrol and to estimate association constants for complex formation.
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- 2014
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31. Prolonged Exposure of Primary Human Muscle Cells to Plasma Fatty Acids Associated with Obese Phenotype Induces Persistent Suppression of Muscle Mitochondrial ATP Synthase β Subunit.
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Lee Tran, Paul D Hanavan, Latoya E Campbell, Elena De Filippis, Douglas F Lake, Dawn K Coletta, Lori R Roust, Lawrence J Mandarino, Chad C Carroll, and Christos S Katsanos
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Medicine ,Science - Abstract
Our previous studies show reduced abundance of the β-subunit of mitochondrial H+-ATP synthase (β-F1-ATPase) in skeletal muscle of obese individuals. The β-F1-ATPase forms the catalytic core of the ATP synthase, and it is critical for ATP production in muscle. The mechanism(s) impairing β-F1-ATPase metabolism in obesity, however, are not completely understood. First, we studied total muscle protein synthesis and the translation efficiency of β-F1-ATPase in obese (BMI, 36±1 kg/m2) and lean (BMI, 22±1 kg/m2) subjects. Both total protein synthesis (0.044±0.006 vs 0.066±0.006%·h-1) and translation efficiency of β-F1-ATPase (0.0031±0.0007 vs 0.0073±0.0004) were lower in muscle from the obese subjects when compared to the lean controls (P
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- 2016
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32. Cullin4 Is Pro-Viral during West Nile Virus Infection of Culex Mosquitoes.
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Prasad N Paradkar, Jean-Bernard Duchemin, Julio Rodriguez-Andres, Lee Trinidad, and Peter J Walker
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Immunologic diseases. Allergy ,RC581-607 ,Biology (General) ,QH301-705.5 - Abstract
Although mosquitoes serve as vectors of many pathogens of public health importance, their response to viral infection is poorly understood. It also remains to be investigated whether viruses deploy some mechanism to be able to overcome this immune response. Here, we have used an RNA-Seq approach to identify differentially regulated genes in Culex quinquefasciatus cells following West Nile virus (WNV) infection, identifying 265 transcripts from various cellular pathways that were either upregulated or downregulated. Ubiquitin-proteasomal pathway genes, comprising 12% of total differentially regulated genes, were selected for further validation by real time RT-qPCR and functional analysis. It was found that treatment of infected cells with proteasomal inhibitor, MG-132, decreased WNV titers, indicating importance of this pathway during infection process. In infection models, the Culex ortholog of mammalian Cul4A/B (cullin RING ubiquitin ligase) was found to be upregulated in vitro as well as in vivo, especially in midguts of mosquitoes. Gene knockdown using dsRNA and overexpression studies indicated that Culex Cul4 acts as a pro-viral protein by degradation of CxSTAT via ubiquitin-proteasomal pathway. We also show that gene knockdown of Culex Cul4 leads to activation of the Jak-STAT pathway in mosquitoes leading to decrease viral replication in the body as well as saliva. Our results suggest a novel mechanism adopted by WNV to overcome mosquito immune response and increase viral replication.
- Published
- 2015
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33. Modernizing reference genome assemblies.
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Deanna M Church, Valerie A Schneider, Tina Graves, Katherine Auger, Fiona Cunningham, Nathan Bouk, Hsiu-Chuan Chen, Richa Agarwala, William M McLaren, Graham R S Ritchie, Derek Albracht, Milinn Kremitzki, Susan Rock, Holland Kotkiewicz, Colin Kremitzki, Aye Wollam, Lee Trani, Lucinda Fulton, Robert Fulton, Lucy Matthews, Siobhan Whitehead, Will Chow, James Torrance, Matthew Dunn, Glenn Harden, Glen Threadgold, Jonathan Wood, Joanna Collins, Paul Heath, Guy Griffiths, Sarah Pelan, Darren Grafham, Evan E Eichler, George Weinstock, Elaine R Mardis, Richard K Wilson, Kerstin Howe, Paul Flicek, and Tim Hubbard
- Subjects
Biology (General) ,QH301-705.5 - Published
- 2011
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34. Intranasal flu vaccine protective against seasonal and H5N1 avian influenza infections.
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Mohammed Alsharifi, Yoichi Furuya, Timothy R Bowden, Mario Lobigs, Aulikki Koskinen, Matthias Regner, Lee Trinidad, David B Boyle, and Arno Müllbacher
- Subjects
Medicine ,Science - Abstract
BACKGROUND: Influenza A (flu) virus causes significant morbidity and mortality worldwide, and current vaccines require annual updating to protect against the rapidly arising antigenic variations due to antigenic shift and drift. In fact, current subunit or split flu vaccines rely exclusively on antibody responses for protection and do not induce cytotoxic T (Tc) cell responses, which are broadly cross-reactive between virus strains. We have previously reported that gamma-ray inactivated flu virus can induce cross-reactive Tc cell responses. METHODOLOGY/PRINCIPAL FINDING: Here, we report that intranasal administration of purified gamma-ray inactivated human influenza A virus preparations (gamma-Flu) effectively induces heterotypic and cross-protective immunity. A single intranasal administration of gamma-A/PR8[H1N1] protects mice against lethal H5N1 and other heterotypic infections. CONCLUSIONS/SIGNIFICANCE: Intranasal gamma-Flu represents a unique approach for a cross-protective vaccine against both seasonal as well as possible future pandemic influenza A virus infections.
- Published
- 2009
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35. Stromal protein degradation is incomplete in Arabidopsis thaliana autophagy mutants undergoing natural senescence
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Lee Travis A, Vande Wetering Scott W, and Brusslan Judy A
- Subjects
Autophagy ,Leaf senescence ,Stromal protein degradation ,Medicine ,Biology (General) ,QH301-705.5 ,Science (General) ,Q1-390 - Abstract
Abstract Background Degradation of highly abundant stromal proteins plays an important role in the nitrogen economy of the plant during senescence. Lines of evidence supporting proteolysis within the chloroplast and outside the chloroplast have been reported. Two extra-plastidic degradation pathways, chlorophagy and Rubisco Containing Bodies, rely on cytoplasmic autophagy. Results In this work, levels of three stromal proteins (Rubisco large subunit, chloroplast glutamine synthetase and Rubisco activase) and one thylakoid protein (the major light harvesting complex protein of photosystem II) were measured during natural senescence in WT and in two autophagy T-DNA insertion mutants (atg5 and atg7). Thylakoid-localized protein decreased similarly in all genotypes, but stromal protein degradation was incomplete in the two atg mutants. In addition, degradation of two stromal proteins was observed in chloroplasts isolated from mid-senescence leaves. Conclusions These data suggest that autophagy does contribute to the complete proteolysis of stromal proteins, but does not play a major degenerative role. In addition, support for in organello degradation is provided.
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- 2013
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36. Examination of actin and microtubule dependent APC localisations in living mammalian cells
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Adams Matthew, Lee Tracy, Askham Jon M, Langford Kelly J, and Morrison Ewan E
- Subjects
Cytology ,QH573-671 - Abstract
Abstract Background The trafficking of the adenomatous polyposis coli (APC) tumour suppressor protein in mammalian cells is a perennially controversial topic. Immunostaining evidence for an actin-associated APC localisation at intercellular junctions has been previously presented, though live imaging of mammalian junctional APC has not been documented. Results Using live imaging of transfected COS-7 cells we observed intercellular junction-associated pools of GFP-APC in addition to previously documented microtubule-associated GFP-APC and a variety of minor localisations. Although both microtubule and junction-associated populations could co-exist within individual cells, they differed in their subcellular location, dynamic behaviour and sensitivity to cytoskeletal poisons. GFP-APC deletion mutant analysis indicated that a protein truncated immediately after the APC armadillo repeat domain retained the ability to localise to adhesive membranes in transfected cells. Supporting this, we also observed junctional APC immunostaining in cultures of human colorectal cancer cell line that express truncated forms of APC. Conclusion Our data indicate that APC can be found in two spatially separate populations at the cell periphery and these populations can co-exist in the same cell. The first localisation is highly dynamic and associated with microtubules near free edges and in cell vertices, while the second is comparatively static and is closely associated with actin at sites of cell-cell contact. Our imaging confirms that human GFP-APC possesses many of the localisations and behaviours previously seen by live imaging of Xenopus GFP-APC. However, we report the novel finding that GFP-APC puncta can remain associated with the ends of shrinking microtubules. Deletion analysis indicated that the N-terminal region of the APC protein mediated its junctional localisation, consistent with our observation that truncated APC proteins in colon cancer cell lines are still capable of localising to the cell cortex. This may have implications for the development of colorectal cancer.
- Published
- 2006
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37. Trapping of normal EB1 ligands in aggresomes formed by an EB1 deletion mutant
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Askham Jon M, Adams Matthew, Lee Tracy, Milward Kelly, Riess Nick P, and Morrison Ewan E
- Subjects
Cytology ,QH573-671 - Abstract
Abstract Background EB1 is a microtubule tip-associated protein that interacts with the APC tumour suppressor protein and the p150glued subunit of dynactin. We previously reported that an EB1 deletion mutant that retains both of these interactions but does not directly associate with microtubules (EB1-ΔN2-GFP) spontaneously formed perinuclear aggregates when expressed in COS-7 cells. Results In the present study live imaging indicated that EB1-ΔN2-GFP aggregates underwent dynamic microtubule-dependent changes in morphology and appeared to be internally cohesive. EB1-ΔN2-GFP aggregates were phase-dense structures that displayed microtubule-dependent accumulation around the centrosome, were immunoreactive for both the 20s subunit of the proteasome and ubiquitin, and induced the collapse of the vimentin cytoskeleton. Fractionation studies revealed that a proportion of EB1-ΔN2-GFP was detergent-insoluble and ubiquitylated, indicating that EB1-ΔN2-GFP aggregates are aggresomes. Immunostaining also revealed that APC and p150glued were present in EB1-ΔN2-GFP aggregates, whereas EB3 was not. Furthermore, evidence for p150glued degradation was found in the insoluble fraction of EB1-ΔN2-GFP transfected cultures. Conclusion Our data indicate that aggresomes can be internally cohesive and may not represent a simple "aggregate of aggregates" assembled around the centrosome. Our observations also indicate that a partially misfolded protein may retain the ability to interact with its normal physiological ligands, leading to their co-assembly into aggresomes. This supports the idea that the trapping and degradation of co-aggregated proteins might contribute to human pathologies characterised by aggresome formation.
- Published
- 2005
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38. Classification Through Graphical Models: Evidences From the EU-SILC Data
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Manuela Cazzaro, Federica Nicolussi, Agnese Maria Di Brisco, Chadjipadelis, T, Lausen, B, Markos, A, Lee, TR, Montanari, A, Nugent, R, Nicolussi, F, Di Brisco, A, and Cazzaro, M
- Subjects
Perceived health ,Computer science ,Bayesian learning procedure ,Chain regression graph model ,Bayesian inference ,computer.software_genre ,Set (abstract data type) ,Graph (abstract data type) ,media_common.cataloged_instance ,Graphical model ,Data mining ,Special case ,European union ,Personally identifiable information ,Categorical variable ,computer ,media_common - Abstract
The purpose of this work is to evaluate the level of perceived health by studying possible factors such as personal information, economic status, and use of free time. The analysis is carried out on the European Union Statistics on Income and Living Conditions (EU-SILC) survey covering 31 European countries. At this aim, we take advantage of graphical models that are suitable tools to represent complex dependence structures among a set of variables. In particular, we consider a special case of Chain Graph model, known as Chain Graph models of type IV for categorical variables. We implement a Bayesian learning procedure to discover the graph which best represents the dataset. Finally, we perform a classification algorithm based on classification trees to identify clusters.
- Published
- 2021
39. Academic goals, achievement, and age at first sexual intercourse: longitudinal, bidirectional influences.
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Schvaneveldt PL, Miller BC, Berry EH, and Lee TR
- Abstract
This study examined bidirectional relationships between age at first sexual intercourse and academic goals and achievement. It was hypothesized that lower educational goals and achievement would be associated with initiating sexual intercourse at a younger age, and that initiating sexual activity early would be associated with a decrease in subsequent academic achievement and goals. In longitudinal data spanning 11 years, evidence was found for bidirectional effects. One interpretation of these results is that adolescents with high educational goals and achievement delay having intercourse because of the perceived risks (e.g., pregnancy and sexually transmitted diseases may jeopardize their plans for the future). Conversely, adolescents who engage in sexual intercourse at young ages might undergo a change in attitudes, including reduced interest in academic achievement and goals. The specific educational variables most strongly related to adolescent sexual intercourse in this study differed substantially by race and gender. [ABSTRACT FROM AUTHOR]
- Published
- 2001
40. Toward a Circular Lithium Economy with Electrodialysis: Upcycling Spent Battery Leachates with Selective and Bipolar Ion-Exchange Membranes.
- Author
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Foo ZH, Lee TR, Wegmueller JM, Heath SM, and Lienhard JH
- Subjects
- Ion Exchange, Membranes, Artificial, Dialysis, Lithium chemistry, Electric Power Supplies, Recycling
- Abstract
Recycling spent lithium-ion batteries offers a sustainable solution to reduce ecological degradation from mining and mitigate raw material shortages and price volatility. This study investigates using electrodialysis with selective and bipolar ion-exchange membranes to establish a circular economy for lithium-ion batteries. An experimental data set of over 1700 ion concentration measurements across five current densities, two solution compositions, and three pH levels supports the techno-economic analysis. Selective electrodialysis (SED) isolates lithium ions from battery leachates, yielding a 99% Li-pure retentate with 68.8% lithium retention, achieving relative ionic fluxes up to 2.41 for Li
+ over transition metal cations and a selectivity of 5.64 over monovalent cations. Bipolar membrane electrodialysis (BMED) converts LiCl into high-purity LiOH and HCl, essential for battery remanufacturing and reducing acid consumption via acid recycling. High current densities reduce ion leakage, achieving lithium leakage as low as 0.03%, though hydronium and hydroxide leakage in BMED remains high at 11-20%. Our analysis projects LiOH production costs between USD 1.1 and 3.6 per kilogram, significantly lower than current prices. Optimal SED and BMED conditions are identified, emphasizing the need to control proton transport in BMED and improve cobalt-lithium separation in SED to enhance cost efficiency.- Published
- 2024
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41. Precursor Development and Aerosol-Assisted Chemical Vapour Deposition for BiVO 4 and W-Doped BiVO 4 Photoanodes: A Universal Ligand Approach.
- Author
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Harris-Lee TR, Surman MK, Straiton AJ, Marken F, and Johnson AL
- Abstract
Green hydrogen production is a key area of importance for advancing into a completely sustainable world, not only for its use in industry and ammonia production, but also for its potential as a new fuel. One promising method for generating green hydrogen is light-driven water splitting using photoelectrodes. Here, a bismuth vanadate (BiVO
4 ) photoanode deposition process was developed using new, bespoke dual-source precursors, tailored for use in aerosol-assisted chemical vapour deposition (AACVD). The resulting thin films were highly nanostructured and consisted of phase-pure monoclinic BiVO4 . Pristine films under 1 sun solar irradiation yielded photocurrent densities of 1.23 mA cm-2 at 1.23 V vs RHE and a peak incident photon-electron conversion efficiency (IPCE) of 82 % at 674 nm, the highest performance of any CVD-grown BiVO4 film to date. A new, AACVD-compatible WO3 precursor was subsequently designed and synthesised for the deposition of W-doped BiVO4 within the same single deposition step., (© 2024 The Authors. ChemSusChem published by Wiley-VCH GmbH.)- Published
- 2024
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42. Role of Transition Metal Dichalcogenides as a Catalyst Support for Decorating Gold Nanoparticles for Enhanced Hydrogen Evolution Reaction.
- Author
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Saeloo B, Saisopa T, Chavalekvirat P, Iamprasertkun P, Jitapunkul K, Sirisaksoontorn W, Lee TR, and Hirunpinyopas W
- Abstract
The two-dimensional (2D) transition metal dichalcogenides (TMDs) have been widely used in various electrochemical applications, such as electrocatalysts, sensors, and energy storage. They have been potentially demonstrated not only as catalysts but also as supporting materials for boosting catalytic performance and durability. However, the different types of TMD nanosheets (transition metals and chalcogenide atoms) for supporting nanoparticles have not yet been investigated for electrocatalytic performance. Herein, we provide mechanistic insights into the hydrogen evolution reaction (HER) of various TMDs (i.e., MoS
2 , MoSe2 , and WSe2 ) as catalyst supports for the decoration of gold nanoparticles (AuNPs), which represent an active catalyst. Among various TMD supports, it was found that the MoS2 supports with an optimal amount of AuNPs loading (MoS2 /AuNPs) exhibited excellent catalytic activity (low overpotential and Tafel slope), which is better than that of other TMD supports and the previously reported TMD-based support. This is due to well-dispersed AuNPs with the charge transfer of Au-MoS2 interaction (increasing n -type), leading to highly active sites for HER performance. Moreover, the perfect laminar stacking of the MoS2 /AuNPs electrode, providing high porosity and good wettability, plays an important role in enhancing the ability of ionic electrolytes to infiltrate through the electrode area (up to ∼50 F g-1 ). The MoS2 /AuNPs exhibit long-term stability with no disintegration of the electrode when performing the HER at ultrahigh current density (>200 mA cm-2 ) for over 24 h. This work aims to deepen the understanding of TMD materials as catalyst supports, and is advantageous for the development of catalyst-based applications.- Published
- 2024
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43. Magnetic Tunability via Control of Crystallinity and Size in Polycrystalline Iron Oxide Nanoparticles.
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Nguyen MD, Deng L, Lee JM, Resendez KM, Fuller M, Hoijang S, Robles-Hernandez F, Chu CW, Litvinov D, Hadjiev VG, Xu S, Phan MH, and Lee TR
- Abstract
Iron oxide nanoparticles (IONPs) are widely used for biomedical applications due to their unique magnetic properties and biocompatibility. However, the controlled synthesis of IONPs with tunable particle sizes and crystallite/grain sizes to achieve desired magnetic functionalities across single-domain and multi-domain size ranges remains an important challenge. Here, a facile synthetic method is used to produce iron oxide nanospheres (IONSs) with controllable size and crystallinity for magnetic tunability. First, highly crystalline Fe
3 O4 IONSs (crystallite sizes above 24 nm) having an average diameter of 50 to 400 nm are synthesized with enhanced ferrimagnetic properties. The magnetic properties of these highly crystalline IONSs are comparable to those of their nanocube counterparts, which typically possess superior magnetic properties. Second, the crystallite size can be widely tuned from 37 to 10 nm while maintaining the overall particle diameter, thereby allowing precise manipulation from the ferrimagnetic to the superparamagnetic state. In addition, demonstrations of reaction scale-up and the proposed growth mechanism of the IONSs are presented. This study highlights the pivotal role of crystal size in controlling the magnetic properties of IONSs and offers a viable means to produce IONSs with magnetic properties desirable for wider applications in sensors, electronics, energy, environmental remediation, and biomedicine., (© 2024 Wiley‐VCH GmbH.)- Published
- 2024
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44. Five years of scanning electrochemical cell microscopy (SECCM): new insights and innovations.
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Gaudin LF, Wright IR, Harris-Lee TR, Jayamaha G, Kang M, and Bentley CL
- Abstract
Scanning electrochemical cell microscopy (SECCM) is a nanopipette-based technique which enables measurement of localised electrochemistry. SECCM has found use in a wide range of electrochemical applications, and due to the wider uptake of this technique in recent years, new applications and techniques have been developed. This minireview has collected all SECCM research articles published in the last 5 years, to demonstrate and celebrate the recent advances, and to make it easier for SECCM researchers to remain well-informed. The wide range of SECCM applications is demonstrated, which are categorised here into electrocatalysis, electroanalysis, photoelectrochemistry, biological materials, energy storage materials, corrosion, electrosynthesis, and instrumental development. In the collection of this library of SECCM studies, a few key trends emerge. (1) The range of materials and processes explored with SECCM has grown, with new applications emerging constantly. (2) The instrumental capabilities of SECCM have grown, with creative techniques being developed from research groups worldwide. (3) The SECCM research community has grown significantly, with adoption of the SECCM technique becoming more prominent.
- Published
- 2024
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45. Optimizing Amorphous Molybdenum Sulfide Thin Film Electrocatalysts: Trade-Off between Specific Activity and Microscopic Porosity.
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Harris-Lee TR, Turvey T, Jayamaha G, Kang M, Marken F, Johnson AL, Zhang J, and Bentley CL
- Abstract
Amorphous molybdenum sulfide (a-MoS
x ) is a promising candidate to replace noble metals as electrocatalysts for the hydrogen evolution reaction (HER) in electrochemical water splitting. So far, understanding of the activity of a-MoSx in relation to its physical (e.g., porosity) and chemical (e.g., Mo/S bonding environments) properties has mostly been derived from bulk electrochemical measurements, which provide limited information about electrode materials that possess microscopic structural heterogeneities. To overcome this limitation, herein, scanning electrochemical cell microscopy (SECCM) has been deployed to characterize the microscopic electrochemical activity of a-MoSx thin films ( ca . 200 nm thickness), which possess a significant three-dimensional structure (i.e., intrinsic porosity) when produced by electrodeposition. A novel two-step SECCM protocol is designed to quantitatively determine spatially resolved electrochemical activity and electrochemical surface area (ECSA) within a single, high-throughput measurement. It is shown for the first time that although the highest surface area (e.g., most porous) regions of the a-MoSx film possess the highest total activity (measured by the electrochemical current), they do not possess the highest specific activity (measured by the ECSA-normalized current density). Instead, the areas of highest specific activity are localized at/around circular structures, coined "pockmarks", which are tens to hundreds of micrometers in size and ubiquitous to a-MoSx films produced by electrodeposition. By coupling this technique with structural and elemental composition analysis techniques (scanning electron microscopy, energy-dispersive X-ray spectroscopy, and X-ray photoelectron spectroscopy) and correlating ECSA with activity and specific activity across SECCM scans, this work furthers the understanding of structure-activity relations in a-MoSx and highlights the importance of local measurements for the systematic and rational design of thin film catalyst materials.- Published
- 2024
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46. Hematological and plasma profiles and ticks and tick-borne pathogens in wild Formosan black bears (Ursus thibetanus formosanus).
- Author
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Tsai YL, Wechtaisong W, Lee TR, Chang CH, Yu PH, and Hwang MH
- Subjects
- Animals, Male, Female, Taiwan epidemiology, Tick-Borne Diseases parasitology, Tick-Borne Diseases veterinary, Tick-Borne Diseases epidemiology, Tick-Borne Diseases blood, Ticks parasitology, Tick Infestations veterinary, Tick Infestations parasitology, Tick Infestations epidemiology, Tick Infestations blood, Animals, Wild parasitology, Ursidae parasitology, Ursidae blood
- Abstract
Background: The endangered Formosan black bear (Ursus thibetanus formosanus) is the largest native carnivorous mammal in Taiwan. Diseases, poor management, illegal hunting, and habitat destruction are serious threats to the survival of bear populations. However, studies on the impact of diseases on bear populations are limited. Therefore, this study aimed to establish a database of the hematological and plasma profiles of free-ranging Formosan black bears and investigate the occurrence of ectoparasites, blood parasites, and vector-borne pathogens., Methods: Formosan black bears were captured in Yushan National Park (YNP) and Daxueshan Forest Recreation Area (DSY) in Taiwan. Blood samples were collected from each bear for hematological analysis and plasma biochemistry using a hematology analyzer. Parasites and pathogens were detected using a thin blood smear with Wright-Giemsa staining and polymerase chain reaction (PCR) assay. Additionally, macroscopic ectoparasites were collected from bears to detect blood parasites and other pathogens. Moreover, the relationships between the bear variables (sex, age, and occurrence of parasites or pathogens), ectoparasites, and infectious agents were also analyzed., Results: In all, 21 wild bears (14 in YNP and 7 in DSY) were captured and released during the satellite tracking studies. Hematological analysis and plasma biochemistry indicated significant differences in white blood cells (WBC), segments, creatine kinase (CK), and lactate dehydrogenase (LDH) levels between foot snare and culvert-captured bears. Additionally, there were significant differences in total plasma protein (TPP), creatinine, Ca
2+ , Mg2+ , and K+ levels between male and female bears. Moreover, pathogen-infected bears had significantly higher erythrocyte sedimentation rate (ESR; 30 min and 1 h) and globulin levels than uninfected bears. In total, 240 ticks were collected from 13 bears, among which eight adult tick species were identified, including Haemaphysalis flava, Haemaphysalis hystricis, Amblyomma testudinarium, Ixodes ovatus, Dermacentor taiwanensis, Haemaphysalis longicornis, Ixodes acutitarsus, Amblyomma javanense, and nymphs belonging to Haemaphysalis spp. PCR revealed that 13 (61.90%) and 8 (38.10%) bears harbored Hepatozoon ursi and Babesia DNA, respectively. Among the ticks examined, 157 (65.41%) and 128 (53.33%) samples were positive for H. ursi and Babesia, respectively., Conclusions: To the best of our knowledge, this is the first study to establish a database of the hematological and plasma profiles of wild Formosan black bears and investigate ectoparasite infestation and Hepatozoon and Babesia spp., Infection: In conclusion, these findings may serve as a reference for monitoring the health and population of locally endangered bears., (© 2024. The Author(s).)- Published
- 2024
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- View/download PDF
47. Geriatric depression and anxiety screening via deep learning using activity tracking and sleep data.
- Author
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Lee TR, Kim GH, and Choi MT
- Subjects
- Humans, Aged, Depression diagnosis, Depression epidemiology, Anxiety diagnosis, Anxiety epidemiology, Anxiety Disorders, Sleep, Deep Learning
- Abstract
Background: Geriatric depression and anxiety have been identified as mood disorders commonly associated with the onset of dementia. Currently, the diagnosis of geriatric depression and anxiety relies on self-reported assessments for primary screening purposes, which is uncomfortable for older adults and can be prone to misreporting. When a more precise diagnosis is needed, additional methods such as in-depth interviews or functional magnetic resonance imaging are used. However, these methods can not only be time-consuming and costly but also require systematic and cost-effective approaches., Objective: The main objective of this study was to investigate the feasibility of training an end-to-end deep learning (DL) model by directly inputting time-series activity tracking and sleep data obtained from consumer-grade wrist-worn activity trackers to identify comorbid depression and anxiety., Methods: To enhance accuracy, the input of the DL model consisted of step counts and sleep stages as time series data, along with minimal depression and anxiety assessment scores as non-time-series data. The basic structure of the DL model was designed to process mixed-input data and perform multi-label-based classification for depression and anxiety. Various DL models, including the convolutional neural network (CNN) and long short-term memory (LSTM), were applied to process the time-series data, and model selection was conducted by comparing the performances of the hyperparameters., Results: This study achieved significant results in the multi-label classification of depression and anxiety, with a Hamming loss score of 0.0946 in the Residual Network (ResNet), by applying a mixed-input DL model based on activity tracking data. The comparison of hyper-parameter performance and the development of various DL models, such as CNN, LSTM, and ResNet contributed to the optimization of time series data processing and achievement of meaningful results., Conclusions: This study can be considered as the first to develop a mixed-input DL model based on activity tracking data for the multi-label identification of late-life depression and anxiety. The findings of the study demonstrate the feasibility and potential of using consumer-grade wrist-worn activity trackers in conjunction with DL models to improve the identification of comorbid mental health conditions in older adults. The study also established a multi-label classification framework for identifying the complex symptoms of depression and anxiety., (© 2024 John Wiley & Sons Ltd.)
- Published
- 2024
- Full Text
- View/download PDF
48. Transfection of Unmodified MicroRNA Using Monolayer-Coated Au Nanoparticles as Gene-Delivery Vehicles.
- Author
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Hoang J, Patil SL, Srinoi P, Liu T, Marquez MD, Khantamat O, Tuntiwechapikul W, Gunaratne PH, and Lee TR
- Subjects
- Humans, Gold chemistry, Transfection, Gene Transfer Techniques, MicroRNAs genetics, Metal Nanoparticles chemistry
- Abstract
This article describes a monolayer-coated gold nanoparticle-based transfection system for the delivery of microRNA (miRNA) into human osteosarcoma (HOS) cells. Two distinct ammonium-terminated adsorbates were used in this study, which provided a platform for ionic bonding of the miRNA onto gold nanoparticles (AuNPs). The custom-designed monolayer-coated gold nanoparticles were characterized by dynamic light scattering, gel mobility shift assay, transmission electron microscopy, ultraviolet-visible spectrometry, zeta potential, and X-ray photoelectron spectroscopy. The miRNA-loaded gold nanoparticles were transfected, and the level of intracellular miRNA delivered and taken up by cells was measured by Taqman qPCR. The overall analysis indicated a successful delivery of miRNA into the HOS cells at an ∼11,000-fold increase compared to nontreated cells.
- Published
- 2024
- Full Text
- View/download PDF
49. Mass-produced gram-negative bacterial outer membrane vesicles activate cancer antigen-specific stem-like CD8 + T cells which enables an effective combination immunotherapy with anti-PD-1.
- Author
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Won S, Lee C, Bae S, Lee J, Choi D, Kim MG, Song S, Lee J, Kim E, Shin H, Basukala A, Lee TR, Lee DS, and Gho YS
- Subjects
- Animals, Mice, Escherichia coli metabolism, Bacterial Outer Membrane metabolism, CD8-Positive T-Lymphocytes, Immunotherapy, Extracellular Vesicles chemistry, Neoplasms therapy, Neoplasms metabolism
- Abstract
Despite the capability of extracellular vesicles (EVs) derived from Gram-negative and Gram-positive bacteria to induce potent anti-tumour responses, large-scale production of bacterial EVs remains as a hurdle for their development as novel cancer immunotherapeutic agents. Here, we developed manufacturing processes for mass production of Escherichia coli EVs, namely, outer membrane vesicles (OMVs). By combining metal precipitation and size-exclusion chromatography, we isolated 357 mg in total protein amount of E. coli OMVs, which was equivalent to 3.93 × 10
15 particles (1.10 × 1010 particles/μg in total protein amounts of OMVs) from 160 L of the conditioned medium. We show that these mass-produced E. coli OMVs led to complete remission of two mouse syngeneic tumour models. Further analysis of tumour microenvironment in neoantigen-expressing tumour models revealed that E. coli OMV treatment causes increased infiltration and activation of CD8+ T cells, especially those of cancer antigen-specific CD8+ T cells with high expression of TCF-1 and PD-1. Furthermore, E. coli OMVs showed synergistic anti-tumour activity with anti-PD-1 antibody immunotherapy, inducing substantial tumour growth inhibition and infiltration of activated cancer antigen-specific stem-like CD8+ T cells into the tumour microenvironment. These data highlight the potent anti-tumour activities of mass-produced E. coli OMVs as a novel candidate for developing next-generation cancer immunotherapeutic agents., (© 2023 The Authors. Journal of Extracellular Vesicles published by Wiley Periodicals, LLC on behalf of the International Society for Extracellular Vesicles.)- Published
- 2023
- Full Text
- View/download PDF
50. Sum frequency generation spectroscopy of fluorinated organic material-based interfaces: a tutorial review.
- Author
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Sakunkaewkasem S, Deleon D, Choi Y, Tran HV, Marquez MD, Baldelli S, and Lee TR
- Abstract
Molecular interactions at interfaces have a significant effect on the wetting properties of surfaces on a macroscale. Sum frequency generation (SFG) spectroscopy, one of a few techniques capable of probing such interactions, generates a surface vibrational spectrum sensitive to molecular structures and has been used to determine the orientation of molecules at interfaces. The purpose of this review is to assess SFG spectroscopy's ability to determine the molecular orientations of interfaces composed of fluorinated organic molecules. We will explore three different types of fluorinated organic material-based interfaces, naming liquid-air, solid-air, and solid-liquid interfaces, to see how SFG spectroscopy can be used to gain valuable and unique information regarding the molecular orientation of each interface. We hope this review will help to broaden the understanding of how to employ SFG spectroscopy to obtain more complex structural information for various fluorinated organic material-based interfaces in the future.
- Published
- 2023
- Full Text
- View/download PDF
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