23 results on '"Penn, Rebecca"'
Search Results
2. Optimized protocol for a quantitative SARS-CoV-2 duplex RT-qPCR assay with internal human sample sufficiency control
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Rowan, Aileen G., May, Philippa, Badhan, Anjna, Herrera, Carolina, Watber, Patricia, Penn, Rebecca, Crone, Michael A., Storch, Marko, Garson, Jeremy A., McClure, Myra, Freemont, Paul S., Madona, Pinglawathee, Randell, Paul, and Taylor, Graham P.
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- 2021
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3. The furin cleavage site in the SARS-CoV-2 spike protein is required for transmission in ferrets
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Peacock, Thomas P., Goldhill, Daniel H., Zhou, Jie, Baillon, Laury, Frise, Rebecca, Swann, Olivia C., Kugathasan, Ruthiran, Penn, Rebecca, Brown, Jonathan C., Sanchez-David, Raul Y., Braga, Luca, Williamson, Maia Kavanagh, Hassard, Jack A., Staller, Ecco, Hanley, Brian, Osborn, Michael, Giacca, Mauro, Davidson, Andrew D., Matthews, David A., and Barclay, Wendy S.
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- 2021
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4. Drugs that inhibit TMEM16 proteins block SARS-CoV-2 spike-induced syncytia
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Braga, Luca, Ali, Hashim, Secco, Ilaria, Chiavacci, Elena, Neves, Guilherme, Goldhill, Daniel, Penn, Rebecca, Jimenez-Guardeño, Jose M., Ortega-Prieto, Ana M., Bussani, Rossana, Cannatà, Antonio, Rizzari, Giorgia, Collesi, Chiara, Schneider, Edoardo, Arosio, Daniele, Shah, Ajay M., Barclay, Wendy S., Malim, Michael H., Burrone, Juan, and Giacca, Mauro
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- 2021
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5. Comparison of single radial immunodiffusion, SDS-PAGE and HPLC potency assays for inactivated influenza vaccines shows differences in ability to predict immunogenicity of haemagglutinin antigen
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Engelhardt, Othmar G., Edge, Chantal, Dunleavy, Una, Guilfoyle, Kate, Harvey, Ruth, Major, Diane, Newman, Robert, Penn, Rebecca, Skeldon, Sarah, Storey, Claire, Wheeler, Jun, Wood, John, and Minor, Philip
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- 2018
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6. Divergent performance of vaccines in the UK autumn 2023 COVID-19 booster campaign
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Shawe-Taylor, Marianne, Greenwood, David, Hobbs, Agnieszka, Dowgier, Giulia, Penn, Rebecca, Sanderson, Theo, Stevenson-Leggett, Phoebe, Bazire, James, Harvey, Ruth, Libri, Vincenzo, Kassiotis, George, Gamblin, Steve, Lewis, Nicola S, Williams, Bryan, Swanton, Charles, Gandhi, Sonia, Carr, Edward J, Wu, Mary Y, Bauer, David L V, and Wall, Emma C
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- 2024
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7. Self-amplifying RNA SARS-CoV-2 lipid nanoparticle vaccine candidate induces high neutralizing antibody titers in mice
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McKay, Paul F., Hu, Kai, Blakney, Anna K., Samnuan, Karnyart, Brown, Jonathan C., Penn, Rebecca, Zhou, Jie, Bouton, Clément R., Rogers, Paul, Polra, Krunal, Lin, Paulo J. C., Barbosa, Christopher, Tam, Ying K., Barclay, Wendy S., and Shattock, Robin J.
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- 2020
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8. 'Drugs Don't Have Age Limits': The Challenge of Setting Age Restrictions for Supervised Injection Facilities
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Watson, Tara Marie, Strike, Carol, Gillian, Kolla, Penn, Rebecca, and Bayoumi, Ahmed M.
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Aims: People under age 18 who inject drugs represent a population at risk of health and social harms. Age restrictions at harm reduction programmes often formally exclude this population, but the reason behind such restrictions is lacking in the literature. To help fill this gap, we examine the perspectives of people who use drugs and various other stakeholders regarding whether supervised injection facilities (SIFs) should have age restrictions. Methods: Interviews and focus groups were conducted with a total of 95 people who use drugs and 141 other stakeholders (including police, fire and emergency services personnel, other city employees and officials, healthcare providers, residents and business representatives) in two Canadian cities without SIFs. Findings: We highlight the following thematic areas: mixed opinions regarding specific age restrictions; safety as a priority; different experiences and understandings of youth, agency and drug use; and ideas regarding maturity, ''help'' and other approaches. We note throughout that a familiar vulnerability--agency dichotomy often surfaced in the discussions. Conclusions: This paper contributes new empirical insights regarding youth access to SIFs. We offer considerations that may inform discussions occurring in other jurisdictions debating SIF implementation and may help remove or clarify age-related policies for harm reduction programmes.
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- 2015
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9. Design considerations for supervised consumption facilities (SCFs): Preferences for facilities where people can inject and smoke drugs
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Watson, Tara Marie, Strike, Carol, Kolla, Gillian, Penn, Rebecca, Jairam, Jennifer, Hopkins, Shaun, Luce, Janine, Degani, Naushaba, Millson, Peggy, and Bayoumi, Ahmed M.
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- 2013
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10. Levels of Influenza A Virus Defective Viral Genomes Determine Pathogenesis in the BALB/c Mouse Model.
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Penn, Rebecca, Tregoning, John S., Flight, Katie E., Baillon, Laury, Frise, Rebecca, Goldhill, Daniel H., Johansson, Cecilia, and Barclay, Wendy S.
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VIRAL genomes , *INFLUENZA A virus , *INFLUENZA viruses , *PLANT viruses , *LABORATORY mice , *INFLUENZA , *VIRUS diseases , *ANIMAL disease models - Abstract
Defective viral genomes (DVGs), which are generated by the viral polymerase in error during RNA replication, can trigger innate immunity and are implicated in altering the clinical outcome of infection. Here, we investigated the impact of DVGs on innate immunity and pathogenicity in a BALB/c mouse model of influenza virus infection. We generated stocks of influenza viruses containing the internal genes of an H5N1 virus that contained different levels of DVGs (indicated by different genome-to-PFU ratios). In lung epithelial cells, the high-DVG stock was immunostimulatory at early time points postinfection. DVGs were amplified during virus replication in myeloid immune cells and triggered proinflammatory cytokine production. In the mouse model, infection with the different virus stocks produced divergent outcomes. The high-DVG stock induced an early type I interferon (IFN) response that limited viral replication in the lungs, resulting in minimal weight loss. In contrast, the virus stock with low levels of DVGs replicated to high titers and amplified DVGs over time, resulting in elevated levels of proinflammatory cytokines accompanied by rapid weight loss and increased morbidity and mortality. Our results suggest that the timing and levels of immunostimulatory DVGs generated during infection contribute to H5N1 pathogenesis. [ABSTRACT FROM AUTHOR]
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- 2022
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11. Latent Cytomegalovirus Infection and Previous Capsular Polysaccharide Vaccination Predict Poor Vaccine Responses in Older Adults, Independent of Chronic Kidney Disease.
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Wall, Nadezhda, Godlee, Alexandra, Geh, Daniel, Jones, Charlotte, Faustini, Sian, Harvey, Ruth, Penn, Rebecca, Chanouzas, Dimitrios, Nightingale, Peter, O'Shea, Matthew, Richter, Alex, Moss, Paul, Cunningham, Adam, and Harper, Lorraine
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CHRONIC kidney failure ,POLYSACCHARIDES ,INFLUENZA vaccines ,FLOW cytometry ,CONFIDENCE intervals ,CYTOMEGALOVIRUS diseases ,PNEUMOCOCCAL vaccines ,REGRESSION analysis ,IMMUNIZATION of older people ,ENZYME-linked immunosorbent assay ,DESCRIPTIVE statistics ,IMMUNITY ,ODDS ratio ,LYMPHOCYTE count ,T helper cells - Abstract
Background Patients with chronic kidney disease (CKD) are more prone to severe infection. Vaccination is a key strategy to reduce this risk. Some studies suggest vaccine efficacy may be reduced in patients with CKD, despite preserved maintenance of long-term responses to some pathogens and vaccines. Here, we investigated immune responses to 2 vaccines in patients with CKD to identify predictors of immunological responsiveness. Methods Individuals >65 years old, with or without nondialysis CKD (n = 36 and 29, respectively), were vaccinated with a nonadjuvanted seasonal influenza vaccine (T-dependent) and Pneumovax23 (23-valent pneumococcal polysaccharide [PPV23], T-independent). Humoral responses were measured at baseline, day 28, and 6 months. Lymphocyte subset and plasma cell/blast analyses were performed using flow cytometry. Cytomegalovirus (CMV) serotyping was assessed by enzyme-linked immunosorbent assay. Results Only modest responsiveness was observed to both vaccines, independent of CKD status (25% adequate response in controls vs. 12%–18% in the CKD group). Unexpectedly, previous immunization with PPV23 (median 10-year interval) and CMV seropositivity were associated with poor PPV23 responsiveness in both study groups (P <.001 and.003, respectively; multivariable linear regression model). Patients with CKD displayed expanded circulating populations of T helper 2 and regulatory T cells, which were unrelated to vaccine responses. Despite fewer circulating B cells, patients with CKD were able to mount a similar day 7 plasma cell/blast response to controls. Conclusion Patients with nondialysis CKD can respond similarly to vaccines as age- and sex-matched healthy individuals. CKD patients display an immune signature that is independent of vaccine responsiveness. Prior PPV23 immunization and CMV infection may influence responsiveness to vaccination. Clinical Trials Registration. NCT02535052 [ABSTRACT FROM AUTHOR]
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- 2021
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12. SARS-CoV-2 lateral flow assays for possible use in national covid-19 seroprevalence surveys (React 2): diagnostic accuracy study.
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Moshe, Maya, Daunt, Anna, Flower, Barnaby, Simmons, Bryony, Brown, Jonathan C., Frise, Rebecca, Penn, Rebecca, Kugathasan, Ruthiran, Petersen, Claire, Stockmann, Helen, Ashby, Deborah, Riley, Steven, Atchison, Christina, Taylor, Graham P., Satkunarajah, Sutha, Naar, Lenny, Klaber, Robert, Badhan, Anjna, Rosadas, Carolina, and Marchesin, Federica
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FLOW cytometry ,CONFIDENCE intervals ,SERODIAGNOSIS ,COVID-19 ,SURVEYS ,DESCRIPTIVE statistics ,ENZYME-linked immunosorbent assay ,DATA analysis software ,SARS disease - Published
- 2021
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13. Clinical and laboratory evaluation of SARS-CoV-2 lateral flow assays for use in a national COVID-19 seroprevalence survey.
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Flower, Barnaby, Brown, Jonathan C., Simmons, Bryony, Moshe, Maya, Frise, Rebecca, Penn, Rebecca, Kugathasan, Ruthiran, Petersen, Claire, Daunt, Anna, Ashby, Deborah, Riley, Steven, Atchison, Christina Joanne, Taylor, Graham P., Satkunarajah, Sutha, Naar, Lenny, Klaber, Robert, Badhan, Anjna, Rosadas, Carolina, Khan, Maryam, and Fernandez, Natalia
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COVID-19 ,SARS-CoV-2 ,PATHOLOGICAL laboratories ,SEROPREVALENCE ,ANTIBODY titer - Abstract
Background: Accurate antibody tests are essential to monitor the SARS-CoV-2 pandemic. Lateral flow immunoassays (LFIAs) can deliver testing at scale. However, reported performance varies, and sensitivity analyses have generally been conducted on serum from hospitalised patients. For use in community testing, evaluation of finger-prick self-tests, in non-hospitalised individuals, is required.Methods: Sensitivity analysis was conducted on 276 non-hospitalised participants. All had tested positive for SARS-CoV-2 by reverse transcription PCR and were ≥21 days from symptom onset. In phase I, we evaluated five LFIAs in clinic (with finger prick) and laboratory (with blood and sera) in comparison to (1) PCR-confirmed infection and (2) presence of SARS-CoV-2 antibodies on two 'in-house' ELISAs. Specificity analysis was performed on 500 prepandemic sera. In phase II, six additional LFIAs were assessed with serum.Findings: 95% (95% CI 92.2% to 97.3%) of the infected cohort had detectable antibodies on at least one ELISA. LFIA sensitivity was variable, but significantly inferior to ELISA in 8 out of 11 assessed. Of LFIAs assessed in both clinic and laboratory, finger-prick self-test sensitivity varied from 21% to 92% versus PCR-confirmed cases and from 22% to 96% versus composite ELISA positives. Concordance between finger-prick and serum testing was at best moderate (kappa 0.56) and, at worst, slight (kappa 0.13). All LFIAs had high specificity (97.2%-99.8%).Interpretation: LFIA sensitivity and sample concordance is variable, highlighting the importance of evaluations in setting of intended use. This rigorous approach to LFIA evaluation identified a test with high specificity (98.6% (95%CI 97.1% to 99.4%)), moderate sensitivity (84.4% with finger prick (95% CI 70.5% to 93.5%)) and moderate concordance, suitable for seroprevalence surveys. [ABSTRACT FROM AUTHOR]- Published
- 2020
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14. Determinants of Foreign Direct Investment in India
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Penn, Rebecca and Aker, Melek Şule
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Unit Root Test ,Johanson Co-Integration ,Marketing Management ,India ,Investments ,Foreign Direct Investment ,VECM and India ,Foreign ,Business Administration - Abstract
The main aim of this thesis is to analyze the determinants of foreign direct investment in India by using GDP, Inflation, Economy Openness and Real Effective Exchange rate as determining variables. This study uses time series data from 1978 to 2014. The unit root test revealed that the variables were stationary at first level I(1). The variables were found to be co-integrated after conducting the Johanson’s Co-integration text. In order to determine the long run coefficients of the variables, we used the Vector Error Correction Model (VECM) that produced the following results. GDP was found to be positive and statistically significant variable exhibiting a positive relationship between FDI and GDP. The VECM reveals exchange rate as a significant determinant of FDI in India. This indicates that the strength of India’s currency is a measure factor in attracting FDI to India. The results of this study also provide evidence that inflation is negatively related to FDI in the long run probably because of the instability it causes in the economy. Trade openness is negative and statistically significant indicating a negative relationship with FDI probably because investors coming in are market seeking oriented and not export oriented. Also, trade openness may increase the number of competitors in the domestic market. Keywords: Foreign Direct Investment, Unit root test, Johanson Co-integration, VECM and India. Öz: Bu tezin temel amacı Hindistan'a yapılan doğrudan yabancı yatırımın (DDY) belirleyicilerini belirleme ve değişkenleri olarak GSYİH, Enflasyon, Ekonomik Açıklık ve Gerçek Etkili Kur kullanarak analiz etmektir. Bu çalışma, 1978-2014 yılları arasındaki zaman serileri verilerini kullanmaktadır. Birim kök testi, değişkenlerin birinci basamak I'de sabit olduğunu ortaya koymaktadır (1). Değişkenlerin, Johanson'un Eş Bütünleştirme metnini uyguladıktan sonra birlikte entegre oldukları bulundu. Değişkenlerin uzun dönem katsayılarını saptamak için aşağıdaki sonuçları üreten VECM (Vector Error Correction Model) kullanılmıştır. GSYİH'nin pozitif olduğu ve DDY ile GSYİH arasında pozitif bir ilişki sergileyen istatistiksel olarak anlamlı değişken olduğu tespit edildi. VECM, döviz kurunu Hindistan'da doğrudan yabancı yatırımın önemli bir belirleyicisi olarak ortaya koyuyor. Bu, Hindistan'ın para biriminin gücünün Hindistan'a doğrudan yabancı yatırım çekme ölçütü olduğuna işaret ediyor. Bu çalışmanın sonuçları, enflasyonun muhtemelen ekonomide ortaya çıkardığı istikrarsızlık nedeniyle uzun vadede DYY ile negatif ilişkili olduğuna dair kanıt sağlamaktadır. Ticaretin açıklığı olumsuzdur ve istatistiksel olarak anlamlıdır, muhtemelen DYY ile negatif bir ilişki gösterir çünkü gelen yatırımcılar pazar odaklıdır ve ihracat odaklı değildir. Ayrıca, ticaretin açık olması iç pazardaki rakip sayısını artırabilir. Anahtar Kelimeler Doğrudan Yabancı Yatırım, Birim Kök Testi, Johanson Eşentegrasyonu, VECM ve Hindistan. Master of Arts in Marketing Management. Thesis (M.A.)--Eastern Mediterranean University, Faculty of Business and Economics, Dept. of Business Administration, 2017. Supervisor: Assoc. Prof. Dr. Melek Şule Aker.
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- 2017
15. Establishing expertise: Canadian community-based medical cannabis dispensaries as embodied health movement organisations
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Penn, Rebecca A.
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- 2014
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16. Building recovery capital through peer harm reduction work.
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Penn, Rebecca Ann, Strike, Carol, and Mukkath, Sabin
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Purpose – Peer harm reduction programmes engage service users in service delivery and may help peers to develop employment skills, better health, greater stability, and new goals. Thus far, peer work has not been discussed as an intervention to promote recovery. The purpose of this paper is to provide findings related to two research questions: first,do low-threshold employment programmes have the potential to contribute to positive recovery capital, and if so, how? Second, how are such programmes designed and what challenges do they face in supporting the recovery process? Design/methodology/approach – Using a community-based research approach, data were collected at a Toronto, Canada community health centre using in-depth interviews with peer workers (n=5), staff (n=5), and programme clients (n=4) and two focus groups with peer workers (n=12). A thematic analysis was undertaken to describe the programme model and to explore the mechanisms by which participation contributes to the development of recovery capital. Findings – The design of the Regent Park Community Health Centre peer work model demonstrates how opportunities for participation in community activities may spark cumulative growth in positive recovery capital within the community of PUDs. However, the recovery contagion of peer work may lose momentum with insufficient opportunities for new and experienced peer workers. Originality/value – Using the concept of recovery capital, the authors demonstrate how low-threshold employment interventions have the potential to contribute to the development of positive recovery capital. [ABSTRACT FROM AUTHOR]
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- 2016
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17. Ambivalence about supervised injection facilities among community stakeholders.
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Strike, Carol, Watson, Tara Marie, Kolla, Gillian, Penn, Rebecca, and Bayoumi, Ahmed M.
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DRUG abuse ,DRUG abusers ,DRUG abuse treatment ,TELEPHONE surveys - Abstract
Background: Community stakeholders express a range of opinions about supervised injection facilities (SIFs). We sought to identify reasons for ambivalence about SIFs amongst community stakeholders in two Canadian cities. Findings: We used purposive sampling methods to recruit various stakeholder representatives (n = 141) for key informant interviews or focus group discussions. Data were analyzed using a thematic process. We identified seven reasons for ambivalence about SIFs: lack of personal knowledge of evidence about SIFs; concern that SIF goals are too narrow and the need for a comprehensive response to drug use; uncertainty that the community drug problem is large enough to warrant a SIF(s); the need to know more about the "right" places to locate a SIF(s) to avoid damaging communities or businesses; worry that a SIF(s) will renew problems that existed prior to gentrification; concern that resources for drug use prevention and treatment efforts will be diverted to pay for a SIF(s); and concern that SIF implementation must include evaluation, community consultation, and an explicit commitment to discontinue a SIF(s) in the event of adverse outcomes. Conclusions: Stakeholders desire evidence about potential SIF impacts relevant to local contexts and that addresses perceived potential harms. Stakeholders would also like to see SIFs situated within a comprehensive response to drug use. Future research should determine the relative importance of these concerns and optimal approaches to address them to help guide decision-making about SIFs. [ABSTRACT FROM AUTHOR]
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- 2015
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18. Police Perceptions of Supervised Consumption Sites (SCSs): A Qualitative Study.
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Watson, Tara Marie, Bayoumi, Ahmed, Kolla, Gillian, Penn, Rebecca, Fischer, Benedikt, Luce, Janine, and Strike, Carol
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POLICE ,ACQUISITION of data ,INTERVIEWING ,FOCUS groups ,THEMATIC analysis ,DRUGS of abuse ,DRUG abuse - Abstract
Copyright of Substance Use & Misuse is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
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- 2012
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19. Naïve Human Macrophages Are Refractory to SARS-CoV-2 Infection and Exhibit a Modest Inflammatory Response Early in Infection.
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Zhang, Ziyun, Penn, Rebecca, Barclay, Wendy S., and Giotis, Efstathios S.
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INFLUENZA , *H1N1 influenza , *SARS-CoV-2 , *ADULT respiratory distress syndrome , *INFLAMMATION , *MACROPHAGES , *COVID-19 - Abstract
Involvement of macrophages in the SARS-CoV-2-associated cytokine storm, the excessive secretion of inflammatory/anti-viral factors leading to the acute respiratory distress syndrome (ARDS) in COVID-19 patients, is unclear. In this study, we sought to characterize the interplay between the virus and primary human monocyte-derived macrophages (MDM). MDM were stimulated with recombinant IFN-α and/or infected with either live or UV-inactivated SARS-CoV-2 or with two reassortant influenza viruses containing external genes from the H1N1 PR8 strain and heterologous internal genes from a highly pathogenic avian H5N1 or a low pathogenic human seasonal H1N1 strain. Virus replication was monitored by qRT-PCR for the E viral gene for SARS-CoV-2 or M gene for influenza and TCID50 or plaque assay, and cytokine levels were assessed semiquantitatively with qRT-PCR and a proteome cytokine array. We report that MDM are not susceptible to SARS-CoV-2 whereas both influenza viruses replicated in MDM, albeit abortively. We observed a modest cytokine response in SARS-CoV-2 exposed MDM with notable absence of IFN-β induction, which was instead strongly induced by the influenza viruses. Pre-treatment of MDM with IFN-α enhanced proinflammatory cytokine expression upon exposure to virus. Together, the findings concur that the hyperinflammation observed in SARS-CoV-2 infection is not driven by macrophages. [ABSTRACT FROM AUTHOR]
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- 2022
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20. Drugs that inhibit TMEM16 proteins block SARS-CoV-2 Spike-induced syncytia
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Hashim Ali, Ilaria Secco, Daniel H. Goldhill, Jose M. Jimenez-Guardeño, Luca Braga, Juan Burrone, Giorgia Rizzari, Guilherme Neves, Antonio Cannatà, Edoardo Schneider, Chiara Collesi, Mauro Giacca, Ajay M. Shah, Michael H. Malim, Rebecca Penn, Wendy S. Barclay, Elena Chiavacci, Daniele Arosio, Rossana Bussani, Ana Maria Ortega-Prieto, Braga, Luca, Ali, Hashim, Secco, Ilaria, Chiavacci, Elena, Neves, Guilherme, Goldhill, Daniel, Penn, Rebecca, M Jimenez-Guardeño, Jose, M Ortega-Prieto, Ana, Bussani, Rossana, Cannatà, Antonio, Rizzari, Giorgia, Collesi, Chiara, Schneider, Edoardo, Arosio, Daniele, M Shah, Ajay, S Barclay, Wendy, H Malim, Michael, Burrone, Juan, and Giacca, Mauro
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Male ,0301 basic medicine ,Phospholipid scramblase ,SARS coronavirus ,Cell ,Drug Evaluation, Preclinical ,Anoctamins ,Virus Replication ,Giant Cells ,Article ,SYNCITIA ,Cell Line ,Cell Fusion ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Immune system ,TMEM ,NICLOSAMIDE ,Chloride Channels ,Chlorocebus aethiops ,medicine ,Animals ,Humans ,SPIKE ,Calcium Signaling ,Lung ,Aged ,Aged, 80 and over ,Syncytium ,Multidisciplinary ,Cell fusion ,Chemistry ,SARS-CoV-2 ,COVID-19 ,Phosphatidylserine ,3. Good health ,Cell biology ,030104 developmental biology ,medicine.anatomical_structure ,Viral replication ,Cell culture ,SARS-CoV-2, TMEM, SPIKE, NICLOSAMIDE, SYNCITIA ,Alveolar Epithelial Cells ,030220 oncology & carcinogenesis ,Spike Glycoprotein, Coronavirus ,Female - Abstract
COVID-19 is a disease with unique characteristics that include lung thrombosis1, frequent diarrhoea2, abnormal activation of the inflammatory response3 and rapid deterioration of lung function consistent with alveolar oedema4. The pathological substrate for these findings remains unknown. Here we show that the lungs of patients with COVID-19 contain infected pneumocytes with abnormal morphology and frequent multinucleation. The generation of these syncytia results from activation of the SARS-CoV-2 spike protein at the cell plasma membrane level. On the basis of these observations, we performed two high-content microscopy-based screenings with more than 3,000 approved drugs to search for inhibitors of spike-driven syncytia. We converged on the identification of 83 drugs that inhibited spike-mediated cell fusion, several of which belonged to defined pharmacological classes. We focused our attention on effective drugs that also protected against virus replication and associated cytopathicity. One of the most effective molecules was the antihelminthic drug niclosamide, which markedly blunted calcium oscillations and membrane conductance in spike-expressing cells by suppressing the activity of TMEM16F (also known as anoctamin 6), a calcium-activated ion channel and scramblase that is responsible for exposure of phosphatidylserine on the cell surface. These findings suggest a potential mechanism for COVID-19 disease pathogenesis and support the repurposing of niclosamide for therapy. Lungs from patients who died from COVID-19 show atypical fused cells, the formation of which is mediated by the SARS-CoV-2 spike protein, and drugs that inhibit TMEM16F can prevent spike-induced syncytia formation.
- Published
- 2021
21. Real-time estimation of immunological responses against emerging SARS-CoV-2 variants in the UK: a mathematical modelling study.
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Russell TW, Townsley H, Hellewell J, Gahir J, Shawe-Taylor M, Greenwood D, Hodgson D, Hobbs A, Dowgier G, Penn R, Sanderson T, Stevenson-Leggett P, Bazire J, Harvey R, Fowler AS, Miah M, Smith C, Miranda M, Bawumia P, Mears HV, Adams L, Hatipoglu E, O'Reilly N, Warchal S, Ambrose K, Strange A, Kelly G, Kjar S, Papineni P, Corrah T, Gilson R, Libri V, Kassiotis G, Gamblin S, Lewis NS, Williams B, Swanton C, Gandhi S, Beale R, Wu MY, Bauer DLV, Carr EJ, Wall EC, and Kucharski AJ
- Abstract
Background: The emergence of SARS-CoV-2 variants and COVID-19 vaccination have resulted in complex exposure histories. Rapid assessment of the effects of these exposures on neutralising antibodies against SARS-CoV-2 infection is crucial for informing vaccine strategy and epidemic management. We aimed to investigate heterogeneity in individual-level and population-level antibody kinetics to emerging variants by previous SARS-CoV-2 exposure history, to examine implications for real-time estimation, and to examine the effects of vaccine-campaign timing., Methods: Our Bayesian hierarchical model of antibody kinetics estimated neutralising-antibody trajectories against a panel of SARS-CoV-2 variants quantified with a live virus microneutralisation assay and informed by individual-level COVID-19 vaccination and SARS-CoV-2 infection histories. Antibody titre trajectories were modelled with a piecewise linear function that depended on the key biological quantities of an initial titre value, time the peak titre is reached, set-point time, and corresponding rates of increase and decrease for gradients between two timing parameters. All process parameters were estimated at both the individual level and the population level. We analysed data from participants in the University College London Hospitals-Francis Crick Institute Legacy study cohort (NCT04750356) who underwent surveillance for SARS-CoV-2 either through asymptomatic mandatory occupational health screening once per week between April 1, 2020, and May 31, 2022, or symptom-based testing between April 1, 2020, and Feb 1, 2023. People included in the Legacy study were either Crick employees or health-care workers at three London hospitals, older than 18 years, and gave written informed consent. Legacy excluded people who were unable or unwilling to give informed consent and those not employed by a qualifying institution. We segmented data to include vaccination events occurring up to 150 days before the emergence of three variants of concern: delta, BA.2, and XBB 1.5. We split the data for each wave into two categories: real-time and retrospective. The real-time dataset contained neutralising-antibody titres collected up to the date of emergence in each wave; the retrospective dataset contained all samples until the next SARS-CoV-2 exposure of each individual, whether vaccination or infection., Findings: We included data from 335 participants in the delta wave analysis, 223 (67%) of whom were female and 112 (33%) of whom were male (median age 40 years, IQR 22-58); data from 385 participants in the BA.2 wave analysis, 271 (70%) of whom were female and 114 (30%) of whom were male (41 years, 22-60); and data from 248 participants in the XBB 1.5 wave analysis, 191 (77%) of whom were female, 56 (23%) of whom were male, and one (<1%) of whom preferred not to say (40 years, 21-59). Overall, we included 968 exposures (vaccinations) across 1895 serum samples in the model. For the delta wave, we estimated peak titre values as 490·0 IC
50 (95% credible interval 224·3-1515·9) for people with no previous infection and as 702·4 IC50 (300·8-2322·7) for people with a previous infection before omicron; the delta wave did not include people with a previous omicron infection. For the BA.2 wave, we estimated peak titre values as 858·1 IC50 (689·8-1363·2) for people with no previous infection, 1020·7 IC50 (725·9-1722·6) for people with a previous infection before omicron, and 1422·0 IC50 (679·2-3027·3) for people with a previous omicron infection. For the XBB 1.5 wave, we estimated peak titre values as 703·2 IC50 (415·0-3197·8) for people with no previous infection, 1215·9 IC50 (511·6-7338·7) for people with a previous infection before omicron, and 1556·3 IC50 (757·2-7907·9) for people with a previous omicron infection., Interpretation: Our study shows the feasibility of real-time estimation of antibody kinetics before SARS-CoV-2 variant emergence. This estimation is valuable for understanding how specific combinations of SARS-CoV-2 exposures influence antibody kinetics and for examining how COVID-19 vaccination-campaign timing could affect population-level immunity to emerging variants., Funding: Wellcome Trust, National Institute for Health Research University College London Hospitals Biomedical Research Centre, UK Research and Innovation, UK Medical Research Council, Francis Crick Institute, and Genotype-to-Phenotype National Virology Consortium., Competing Interests: Declaration of interests CSw receives grants from Bristol Myers Squibb, Ono Pharmaceuticals, Boehringer Ingelheim, Roche-Ventana, Pfizer, and Archer Dx; receives personal fees from Genentech, the Sarah Canon Research Institute, Medicxi, Bicycle Therapeutics, GRAIL, Amgen, AstraZeneca, Bristol Myers Squibb, Illumina, GlaxoSmithKline, MSD, and Roche-Ventana; holds stock options in Apogen Biotech, Epic Biosciences, GRAIL, and Achilles Therapeutics; is a member of a scientific advisory board for Bicycle Therapeutics, GRAIL, Relay Therapeutics, SAGA Diagnostics, and Achilles Therapeutics; is a co-founder of Achilles Therapeutics; receives consulting fees from Genentech, Medicxi, MetaboMed, Novartis, the China Innovation Centre of Roche, and the Sarah Cannon Research Institute; and receives honoraria from Amgen, AstraZeneca, Bristol Myers Squibb, Illumina, and Incyte. DLVB receives grants, paid to their institution, from AstraZeneca. EJC is an unpaid member of the Infection, Prevention and Control Committee of the UK Kidney Association. RB and DLVB are members of the Genotype-to-Phenotype 2 Consortium. AJK received the Sir Henry Dale Fellowship, jointly funded by the Wellcome Trust and the Royal Society (grant number 206250/Z/17/Z). AJK and DH were supported by the National Institutes of Health (1R01AI141534–01A1). All other authors declare no competing interests., (Copyright © 2024 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 license. Published by Elsevier Ltd.. All rights reserved.)- Published
- 2024
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22. Handheld Point-of-Care System for Rapid Detection of SARS-CoV-2 Extracted RNA in under 20 min.
- Author
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Rodriguez-Manzano J, Malpartida-Cardenas K, Moser N, Pennisi I, Cavuto M, Miglietta L, Moniri A, Penn R, Satta G, Randell P, Davies F, Bolt F, Barclay W, Holmes A, and Georgiou P
- Abstract
The COVID-19 pandemic is a global health emergency characterized by the high rate of transmission and ongoing increase of cases globally. Rapid point-of-care (PoC) diagnostics to detect the causative virus, SARS-CoV-2, are urgently needed to identify and isolate patients, contain its spread and guide clinical management. In this work, we report the development of a rapid PoC diagnostic test (<20 min) based on reverse transcriptase loop-mediated isothermal amplification (RT-LAMP) and semiconductor technology for the detection of SARS-CoV-2 from extracted RNA samples. The developed LAMP assay was tested on a real-time benchtop instrument (RT-qLAMP) showing a lower limit of detection of 10 RNA copies per reaction. It was validated against extracted RNA from 183 clinical samples including 127 positive samples (screened by the CDC RT-qPCR assay). Results showed 91% sensitivity and 100% specificity when compared to RT-qPCR and average positive detection times of 15.45 ± 4.43 min. For validating the incorporation of the RT-LAMP assay onto our PoC platform (RT-eLAMP), a subset of samples was tested ( n = 52), showing average detection times of 12.68 ± 2.56 min for positive samples ( n = 34), demonstrating a comparable performance to a benchtop commercial instrument. Paired with a smartphone for results visualization and geolocalization, this portable diagnostic platform with secure cloud connectivity will enable real-time case identification and epidemiological surveillance., Competing Interests: The authors declare no competing financial interest., (© 2021 The Authors. Published by American Chemical Society.)
- Published
- 2021
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23. Histopathological findings and viral tropism in UK patients with severe fatal COVID-19: a post-mortem study.
- Author
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Hanley B, Naresh KN, Roufosse C, Nicholson AG, Weir J, Cooke GS, Thursz M, Manousou P, Corbett R, Goldin R, Al-Sarraj S, Abdolrasouli A, Swann OC, Baillon L, Penn R, Barclay WS, Viola P, and Osborn M
- Subjects
- Acute Disease, Humans, Infarction pathology, Lung pathology, SARS-CoV-2, United Kingdom epidemiology, Viral Tropism, COVID-19 epidemiology, Mucormycosis pathology, Pancreatitis pathology, Pericarditis pathology, Thrombosis pathology
- Abstract
Background: Severe COVID-19 has a high mortality rate. Comprehensive pathological descriptions of COVID-19 are scarce and limited in scope. We aimed to describe the histopathological findings and viral tropism in patients who died of severe COVID-19., Methods: In this case series, patients were considered eligible if they were older than 18 years, with premortem diagnosis of severe acute respiratory syndrome coronavirus 2 infection and COVID-19 listed clinically as the direct cause of death. Between March 1 and April 30, 2020, full post-mortem examinations were done on nine patients with confirmed COVID-19, including sampling of all major organs. A limited autopsy was done on one additional patient. Histochemical and immunohistochemical analyses were done, and histopathological findings were reported by subspecialist pathologists. Viral quantitative RT-PCR analysis was done on tissue samples from a subset of patients., Findings: The median age at death of our cohort of ten patients was 73 years (IQR 52-79). Thrombotic features were observed in at least one major organ in all full autopsies, predominantly in the lung (eight [89%] of nine patients), heart (five [56%]), and kidney (four [44%]). Diffuse alveolar damage was the most consistent lung finding (all ten patients); however, organisation was noted in patients with a longer clinical course. We documented lymphocyte depletion (particularly CD8-positive T cells) in haematological organs and haemophagocytosis. Evidence of acute tubular injury was noted in all nine patients examined. Major unexpected findings were acute pancreatitis (two [22%] of nine patients), adrenal micro-infarction (three [33%]), pericarditis (two [22%]), disseminated mucormycosis (one [10%] of ten patients), aortic dissection (one [11%] of nine patients), and marantic endocarditis (one [11%]). Viral genomes were detected outside of the respiratory tract in four of five patients. The presence of subgenomic viral RNA transcripts provided evidence of active viral replication outside the respiratory tract in three of five patients., Interpretation: Our series supports clinical data showing that the four dominant interrelated pathological processes in severe COVID-19 are diffuse alveolar damage, thrombosis, haemophagocytosis, and immune cell depletion. Additionally, we report here several novel autopsy findings including pancreatitis, pericarditis, adrenal micro-infarction, secondary disseminated mucormycosis, and brain microglial activation, which require additional investigation to understand their role in COVID-19., Funding: Imperial Biomedical Research Centre, Wellcome Trust, Biotechnology and Biological Sciences Research Council., (© 2020 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 license.)
- Published
- 2020
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