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Resolution of coronavirus disease 2019 (COVID-19)Habas, Khaled S.A., Nganwuchu, Chinyere C., Shahzad, F., Gopalan, Rajendran C., Haque, M., Rahman, Sayeeda, Majumder, A.A., Nasim, Md. Talat 08 April 2020 (has links)
Yes / Introduction.
Coronavirus disease 2019 (COVID-19) was first detected in China in December, 2019, and declared as a pandemic by the World Health Organization (WHO) on March 11, 2020. The current management of COVID-19 is based generally on supportive therapy and treatment to prevent respiratory failure. The effective option of antiviral therapy and vaccination are currently under evaluation and development.
Areas covered.
A literature search was performed using PubMed between December 1, 2019–June 23, 2020. This review highlights the current state of knowledge on the viral replication and pathogenicity, diagnostic and therapeutic strategies, and management of COVID-19. This review will be of interest to scientists and clinicians and make a significant contribution toward development of vaccines and targeted therapies to contain the pandemic.
Expert Opinion.
The exit strategy for a path back to normal life is required, which should involve a multi-prong effort toward development of new treatment and a successful vaccine to protect public health worldwide and prevent future COVID-19 outbreaks. Therefore, the bench to bedside translational research as well as reverse translational works focusing bedside to bench is very important and would provide the foundation for the development of targeted drugs and vaccines for COVID-19 infections. / Research carried out at TN laboratories are funded by the GrowMedtech, The Royal Society and University of Bradford. KH is supported by a project grant by the GrowMedtech awarded to TN. CW is funded by a Ph.D studentship.
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Longitudinal evaluation of post-COVID-19 conditionsNayyerabadi, Maryam 05 1900 (has links)
Depuis l'émergence de la pandémie de SARS-CoV-2 en décembre 2019, plus de 675 millions de cas confirmés ont été signalés dans le monde, dont 4,6 millions de cas au Canada uniquement. Bien que la plupart des individus récupèrent sans séquelles, 10 à 20 % des survivants signalent des symptômes persistants au-delà de quatre semaines après une infection par le SARS-CoV-2, tels que la fatigue, les altérations cognitives, la toux, l'anxiété, la dépression, la douleur thoracique et autres, connus sous le nom de COVID longue ou de condition post-SARS-CoV-2 (PCC). Par conséquent, la physiopathologie, le diagnostic et la prise en charge de la PCC sont devenus un axe de recherche majeur. Pour contribuer à la compréhension de la PCC, nous avons mené le projet IPCO (Institut de Recherches cliniques de Montréal (IRCM) Post-COVID-19 Research Clinic), en posant comme hypothèses 1 que les personnes infectés par le SARS-CoV-2 au Québec présenteraient des signes et symptômes fréquents et variés post-phase aiguë, affectant différents systèmes d'organes, et 2 Les niveaux élevés de D-dimères dans PCC ne sont pas pertinents pour les événements thromboemboliques 3 que Chez les individus atteints de la PCC, la vaccination contre la COVID-19 réduirait les symptômes de la PCC en diminuant l'inflammation. Pour évaluer ces hypothèses, nous avons recruté des participants âgés de plus de 18 ans, un à 18 mois après l'infection aiguë, présentant au moins un symptôme persistant, et programmé des visites de base et de suivi à 3-6 mois, 1 an et 2 ans post-infection aiguë. Chaque visite comprenait des évaluations cliniques, des prélèvements, des évaluations en laboratoire, des questionnaires sur l'alimentation et le bien-être, ainsi que des évaluations de la physiologie pulmonaire et cardiaque. Sur la base d'une étude allemande qui a catégorisé les symptômes du PCC et les individuals en trois groupes de sévérité, nous avons classé nos participants en trois niveaux de sévérité : non/légère (score du PCC <10,75), modérée (10,75 < score du PCC < 26,25) et sévère (score du PCC > 26,25). Cette thèse présente les résultats de trois sous-études IPCO.
Dans l'étude descriptive, nous avons observé que la fatigue, les problèmes de mémoire et les maux de tête étaient les symptômes de PCC les plus courants, la majorité de nos participants étant des femmes et ayant été traités en ambulatoire pendant la phase aiguë. Dans l'étude transversale, nous avons constaté des différences significatives dans les mesures de santé et de bien-être à tous les moments, mais aucune différence significative dans les résultats des tests physiologiques entre les groupes PCC non/léger, modéré et sévère. Dans l'étude longitudinale, les marqueurs de l'inflammation se sont améliorés au fil du temps, mais le taux métabolique basal et la masse grasse ont augmenté. Dans la deuxième étude, nous avons observé une forte prévalence de participants ayant des niveaux de D-dimères, qui n'étaient pas associés à des événements thromboemboliques, et aucune corrélation entre le niveau de D-dimères et les niveaux de cytokines et de chimiokines. Dans la troisième étude, nous avons observé que les participants vaccinés présentaient significativement moins de symptômes de PCC.
Notre étude fournit une meilleure compréhension de la physiopathologie du PCC et de l'effet de la vaccination sur le profil clinique et inflammatoire du PCC, ce qui pourrait aider à la conception d'outils de gestion clinique et de recherche futurs. / Since the emergence of the SARS-CoV-2 pandemic in December 2019, over 675 million confirmed cases have been reported globally, with 4.6 million cases in Canada alone. Although most individuals recover without residual disease, 10-20% of survivors report symptoms persisting beyond four weeks after SARS-CoV-2 infection, such as fatigue, cognitive impairments, cough, anxiety, depression, chest pain, and others known as long-COVID or post SARS-CoV-2 condition (PCC). Consequently, the pathophysiology, diagnosis, and management of PCC have become a significant focus of research. To contribute to the understanding of PCC, we conducted the IPCO (Institut de Recherches cliniques de Montréal (IRCM) Post-COVID-19 Research Clinic) project, hypothesizing that 1 SARS-CoV-2 infected individuals in Quebec would present frequent and varied signs and symptoms post-acute phase, affecting different organ systems, and that 2 high D-dimer level in PCC is irrelevant to thromboembolic events , and 3 in individuals with PCC, COVID-19 vaccination would decrease PCC symptoms by reducing inflammation. To evaluate these hypotheses, we enrolled participants aged >18 years, one to 18 months post-acute infection, with at least one persistent symptom, and scheduled baseline and follow-up visits at 3-6 months, 1 year, and 2 years post-acute infection. Each visit involved clinical evaluations, sampling, laboratory evaluations, diet and well-being questionnaires, and pulmonary and cardiac physiology evaluations. Based on a German study that categorized PCC symptoms and individuals into three severity groups, we classified our participants into three severity levels: non/mild (PCC score < 10.75), moderate (10.75 < PCC score < 26.25), and severe (PCC score > 26.25). This thesis reports the results of three IPCO studies.
In the descriptive study, we observed that fatigue, memory problems, and headaches were the most common PCC symptoms, with the majority of our participants being female and managed as outpatients during the acute phase. In the cross-sectional study, we noted significant differences in health and well-being measurements at all time points, but no significant difference in physiological tests' results between different severity groups. In the longitudinal study, markers of inflammation improved over time, but the basal metabolic rate and body fat increased. In the second study, we observed a high prevalence of participants having D-dimer levels in blood, which were not associated with thromboembolic events, and no correlation between D-dimer levels and blood cytokine/ chemokine levels. In the third study, we observed that vaccinated participants had significantly fewer PCC symptoms, fewer organ systems affected, higher well-being scores, and lower blood cytokine/chemokine levels than the non-vaccinated group. We also observed correlations between certain cytokines/chemokines, as well as between clinical parameters and certain cytokines/chemokines.
Our study provides a better understanding of the pathophysiology of PCC and effect of vaccination on the clinical and inflammatory profile of PCC, which could assist future research and clinical management tool design.
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Investigating the Substrate Specificity of the Equivalent Papain-like Protease 2 Domain of nsp3 across Alpha- and Beta-CoronavirusesJozlyn Clasman (6632228) 11 June 2019 (has links)
<div>The papain-like protease (PLP) domain of nonstructural protein 3 (nsp3) of the coronavirus (CoV) genome promotes viral replication by processing the CoV polyprotein (protease) and also antagonize innate immune responses by deubiquitinating (DUB) and deISGylating (deISG) host substrates. Selectively removing the DUB/deISG activities of PLP while keeping the protease activity intact is a potential strategy for designing a live attenuated virus. However, it is unclear in the literature the precise mechanism by which PLPs support CoV evasion of the innate immune system. Deciphering the substrate specificity of PLPs for host ubiquitin (Ub) and interferon stimulated gene 15 (ISG15) can therefore help in the design of PLP mutants that selectively lack one activity for evaluating the DUB and deISG mechanism in CoV pathogenesis and replication. </div><div> In this dissertation, we investigate the structure and function of the single PLP (PLpro) from beta-CoVs, severe acute respiratory syndrome coronavirus (SARS-CoV) and Middle East respiratory syndrome coronavirus (MERS-CoV), which are dangerous viral pathogens that emerged from a zoonotic source to cause infectious disease in the human population. Additionally, we translate the knowledge gained to the equivalent PLP2 from alpha-CoV porcine epidemic diarrhea virus (PEDV) and feline infectious peritonitis virus (FIPV), which cause fatal disease in suckling piglets on industrial pork farms and household cats, respectively. The primary objective of this work is to rationally design PLP mutants across beta- and alpha-CoVs to help attenuate CoV infection, as no antiviral or vaccine exist for human CoVs and the efficacy of PEDV vaccines are an ongoing research topic. </div><div><br></div><div>In Chapter 1, different human, animal, and the bat origin CoV strains are introduced. The CoV life-cycle and virion structure are outlined, along with the replicase complex for viral replication. The multidomain nsp3 from alpha- and beta-CoV genomes are also described with a focus on the PLP domain and its proposed cleavage sites of the viral polyprotein. The discovery of the first viral protease DUB and the multiple activities of PLPs are defined, which includes a proposed model of how DUB versus deISG activities may act in the innate immune response. This leads into the therapeutic potential of PLP for an antiviral or live attenuated vaccine, which is followed by the introduction of live attenuated vaccines and the reverse genetics system. Next, proof of concept studies on PLP2 mutants are described and the introduction is concluded by stating the ultimate goal for the design of PLP mutants.</div><div><br></div><div>In Chapter 2, we hypothesize that the flanking ubiquitin-like (Ubl2) domain of MERS-CoV PLpro is not required for its enzymatic function. We characterize the specific activity, kinetics, substrate specificity, and inhibition of the PLpro enzyme with and without the Ubl2 domain and reveal that the Ubl2 domain does not significantly alter PLpro function. We determine the structure of the core PLpro, smallest catalytic unit to 1.9 Å resolution and observed no structural changes compared to the wild-type. Additionally, we demonstrate that a purported MERS-CoV PLpro inhibitor is nonselective in non-reducing conditions and should not be pursed for therapeutic use. We show that the core PLpro enzyme i.e. without the Ubl2 domain is a stable and robust construct for crystallization and is also thermally stable based on thermal melting studies with utility for structure-based drug design. </div><div><br></div><div>In Chapter 3, we shed light on the specificity of SARS-CoV PLpro towards Ub versus ISG15 by characterizing the specific activity and kinetic parameters of SARS-CoV PLpro mutants. In addition, the structure of SARS-CoV PLpro in complex with the C-terminal domain of ISG15 is determined and compared with the Ub-bound structure. Based on the structure and kinetic results, the altered specificities of SARS-CoV PLpro mutants Arg167Glu, Met209Ala, and Gln233Glu are compared with the wild-type. Arg167Glu mutant exhibits DUB hyperactivity and is expected to adopt a more favorable interaction with the Arg42 of Ub. At the same time, ARG167GLU contains a shorter side-chain that hinders interaction with the unique Trp123 of ISG15 for deISG activity compared to the wild-type. These results aid in the development of SARS-CoV PLpro mutants that have directed shifts in substrate specificity for Ub versus ISG15. </div><div><br></div><div>In Chapter 4, the process and antiviral activity of ISGylation is reviewed and how viruses can modulate host-derived versus virus-derived machineries to counteract ISGylation for viral infection. MERS-CoV PLpro is cross-reactive for Ub, but less is known about its specificity towards ISG15. In this study, we determine the structure of MERS-CoV PLpro bound with ISG15 to 2.3 Å resolution and reveal a small hydrophobic pocket of ISG15 that consists of P130 and W123, which differs from Ub hydrophobic patch. We design and determine the kinetic parameters for 13 PLpro mutants and reveal that MERS-CoV PLpro only has a single ubiquitin recognition (SUb1) site. Kinetic studies show that removing the charge of the R1649 greatly enhances DUB/protease activity while mutating in an Arg near R42 of Ub or ISG15 hydrophobic region is detrimental to both DUB/deISG activities. Kinetic experiments and probe-reactivity assays showed that Val1691Arg, Val1691Lys, and His1652Arg mutants are drastically reduced DUB/deISG activities compared to the wild-type. Overall, MERS-CoV PLpro mutants with alter kinetic profiles will be useful for discovery tools and DUB/deISG deficient mutants are great candidates for removing host cell antagonism activity by PLpro for live attenuated vaccines.</div><div><br></div><div>In Chapter 5, the goal is to translate the knowledge gained in Chapters 2-4 on beta-CoVs PLpro and evaluate the substrate specificity of alpha-CoVs FIPV and PEDV PLP2 for mutagenesis experiments. First, we design and purify the core PLP2 enzymes for kinetics. PLP2s are efficient DUBs that prefer Ub to ISG15 in vitro, and this preference is conserved in beta-CoV MHV PLP2 as well as alpha-CoV NL63 PLP2. We determine the structure of alpha-CoV PEDV PLP2 to 1.95 Å resolution and reveal the unique Zn-finger coordinating Cys3-His arrangement of the alpha-CoV genus that differs from past beta-CoV PLP crystal structures. To determine residues of the SUb1 site, we generate a homology model of FIPV PLP2 and overlay our PLP2 structures with MERS-CoV PLpro bound with Ub. In addition, we create electrostatic surface maps across coronaviral PLP subfamilies to evaluate the charge distribution of the SUb1 for the rational design of several FIPV and PEDV PLP2 mutants. We evaluate the turnover of PLP mutants for FRET-based substrates and reveal that His101ArgFIPV and Asn101ArgPEDV are drastically reduced in Ub-AMC activity while their peptide activities are within 2-fold of the wild-type. These mutants show delayed reactivity for Ub probes and no longer cleave Ub-chains displaying isopeptide bonds compared to the wild-type. Results from this study reveal a hot spot in both alpha- and beta-CoVs that can be used to selectively remove DUB activity of PLPs for generating a DUB deficient PLP enzyme. </div><div><br></div><div>In this dissertation, we investigate the substrate specificity of PLPs across alpha- and beta-CoVs and develop a fingerprint for Ub and also shed light on ISG15 recognition. Specifically, hot spots were identified in the SUb1 site of different PLPs, which recognize R42 and hydrophobic Ile44 of Ub. Position 97-98 of PLPs can be used to remove DUB activity by substituting an Arg, but usually effect protease function. Substituting an Arg at position 101 and 136 of coronaviral PLPs serve as the best strategy to remove DUB function while not hindering active site functionality. The DUB/deISG deficient mutants described will be useful for inhibiting the ability of PLPs to function in the innate immune response. Ultimately, this work provides a guide for identifying attenuating mutants in existing CoVs for live attenuated vaccines and also a blueprint for engineering PLPs from new emerging CoVs. </div>
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The impact of the COVID-19 pandemic on mental health of children and adolescentsSrivastava, Gautam January 2020 (has links)
The rapidly spreading pandemic of SARS-CoV-2 (COVID-19) infection with high morbidity and mortality has overwhelmed the global healthcare services. With mysterious origins and the capacity of affecting multiple types of tissues, SARS-CoV-2 has baffled many scientists - which has posed great challenges in the development of pharmaceutical treatments and preventions (i.e., vaccination). The COVID-19 pandemic has also led to a slew of non-pharmaceutical interventions (NPIs) to slow down the spread of the virus. The sudden imposition of these NPIs including social distancing, lock-down, school closures, isolation, and quarantine of suspected cases or contacts, has greatly affected the mental health of children and adolescents. Concerns about the impact of these NPIs on mental health, especially for vulnerable populations such as children and adolescents, have emerged. This study discusses several different aspects of the impact of the COVID-19 pandemic on the mental health of children and adolescents.Accumulating evidence has shown that the vast majority of children and adolescents exposed to the SARS-CoV-2 virus are asymptomatic, although few cases turned unfortunately severely ill. The genomics, microbiology, and biochemistry of this novel coronavirus reveal several peculiarities, making it a tough entity. The profound impact of social distancing along with the closure of schools, parks, and other recreational activities on the delicate minds of children and adolescents makes them irritable, angry, and rebellious. This assumes a major challenge in children with mental health issues or in those with special needs. Lock-down, quarantine and isolation further complicate the mental health issues and are discussed along with remedial measures. The impact of an already overwhelmed medical care system on the mental healthcare quality can be profound and needs a specially chartered approach by the psychiatrists supplementing the COVID-19 control activities. Children/adolescents with neuropsychiatric issues need special care, as they have abnormal impulsive behaviour and actions such as running away, unhygienic acts, spitting etc. All these mental health issues in children and adolescents, who form a sizable population of the society and are the future of the planet, forms the subject matter of this work. Thus, all programmes of COVID-19 control must simultaneously address these important mental health issues of children and adolescents to prevent this ‘parallel pandemic’ of psychiatric disorders. The latter may persist much longer and prove equally challenging and costly.
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Metodología para evaluar el nivel de protección respiratoria de mascarillas y respiradores ante partículas similares a las que transmiten el SARS-CoV-2 / Methodology for evaluating the level of respiratory protection of masks and respirators against particles similar to those that transmit SARS-COV-2Chavez-Ruiz, Manuel, Rueda-Torres, Lenin, Ruffner-Camargo, Betsabé, Bellido-Achahui, Cristofer 05 October 2021 (has links)
Objetivo: Desarrollar una metodología para evaluar el nivel de protección respiratoria de respiradores, mascarillas quirúrgicas y mascarillas comunitarias que usa la población peruana, usando partículas de un tamaño similar a las que contienen al virus activo del SARS-CoV-2. Materiales y métodos: Se ha determinado una relación lineal directa entre el logaritmo de la concentración de partículas suspendidas en aire y el tiempo transcurrido; por lo cual es posible comparar la cantidad de partículas internas y externas a la mascarilla o respirador en un mismo periodo y conocer el porcentaje de protección respiratoria de cada muestra evaluada. Resultados: Se ha logrado implementar una metodología para evaluar el nivel de protección respiratoria ante aerosoles menores a 5,0 μm. Asimismo, el empleo de accesorios como ligas o ajustadores detrás de cabeza y nuca, y el uso de clips nasales robustos, incrementan significativamente el nivel de protección respiratoria ante partículas con alta probabilidad de contener al SARS-CoV-2. Conclusiones: Se observa una concordancia entre los valores de protección respiratoria obtenidos y los esperados, considerando el nivel de filtración del material empleado de cada mascarilla quirúrgica o respirador, y su nivel de ajuste. Se observó un incremento significativo en los niveles de protección respiratoria. / Objective: To develop a methodology for evaluating the level of respiratory protection provided by res- pirators, surgical masks and community face masks used by the Peruvian population; protection was evaluated against particles of a size similar to those containing active SARS-CoV-2 virus. Materials and methods: A direct linear relationship has been determined between the logarithm of the concentration of airborne particles and the elapsed time; thus, it is possible to compare the quantity of particles inside and outside of the mask or respirator in the same time period, as well as to obtain the percentage of re- spiratory protection for each evaluated sample. Results: A methodology was established to evaluate the level of respiratory protection against aerosols smaller than 5.0 μm. Also, the use of accessories such as garters or adjusters behind the head and neck, and the use of strong nasal clips, significantly increased the level of respiratory protection against particles with a high probability of containing SARS-CoV-2. Conclusions: We found concordance between the obtained respiratory protection values and those ex- pected, considering the filtration level of the material used for each surgical mask or resp s well as the tightness. A significant increase in the levels of respiratory protection was observed.
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Disease Tolerance, Epigenetic Inheritance, and Surviving Pathogenic Viral InfectionsSilverstein, Noah J. 18 August 2021 (has links)
Health is often defined in terms of absence of disease or pathological processes, but this is a definition of exclusion and incomplete. For example, SARS-CoV-2 viral load does not reliably predict disease severity, and so individuals must vary in their ability to control inflammation and maintain normal tissue homeostasis. This host defense strategy is called disease tolerance, and better understanding of disease tolerance mechanisms could change the way that we treat disease and work to maintain health.
The first project presented in this dissertation found that after accounting for effects of age and sex, innate lymphoid cells (ILCs), but not T cells, were lower in adults and children sick with COVID-19 or MIS-C, independent of lymphopenia. Furthermore, abundance of ILCs, but not of T cells, correlated inversely with disease severity. These blood ILCs were shown to produce amphiregulin, a protein implicated in disease tolerance and tissue homeostasis, and the percentage of amphiregulin-producing ILCs was lower in males. These results suggest that, by promoting disease tolerance, homeostatic ILCs decrease morbidity and mortality associated with SARS-CoV-2 infection, and that lower ILC abundance accounts for increased COVID-19 severity with age and in males.
The second project describes a novel mouse model of epigenetic inheritance wherein paternal influenza A virus (IAV) infection results in less severe influenza disease in IAV infected offspring. This offspring phenotype was not attributable to differences in viral load, indicating a possible difference in disease tolerance. Paternal caloric deprivation decreased, and influenza B virus infection increased, offspring influenza disease severity, and in vitro fertilization demonstrated sperm are sufficient to transfer IAV-associated epigenetic inheritance phenotypes.
These findings represent a foundation for further work that, by continuing to elucidate the mechanisms of disease tolerance and epigenetic inheritance, could provide novel therapeutic interventions to help promote and maintain health.
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Reactive Blade Coating for Low-Cost Fabrication of Self-Assembled Metal Nanoparticles for Bio-Applications: Disinfecting SARS-CoV-2 to Limit the Spread of COVID-19 IllnessEbrahimzadeh Asl Tabrizi, Bita 30 April 2021 (has links)
Considerable attention has been focused on nanomaterials and their extensive applications. Metallic nanoparticles, especially gold nanoparticles (AuNPs) and silver nanoparticles (AgNPs), due to their superior physical, chemical, and optical properties, are vastly developed for numerous biomedical applications such as drug and gene delivery systems, diagnostic biosensors, imaging, and therapeutics. This study presents a low-cost method for the fabrication of self-assembled metallic nanoparticles, including gold and silver, via a reactive blade coating process, which is carried out based on in situ reduction of the metal precursors. This technique is a roll-to-roll compatible technique suitable for scalable nanomanufacturing. Oleylamine was used as a reducer agent, and gold (III) chloride hydrate and silver salts, including silver nitrate and silver perchlorate hydrate, were used as the metal precursors. Fabrication was carried out by first blade coating the reducer ink and subsequently coating the precursor ink followed by 3 hours of heat treatment. Various solvent systems were used to examine the effect of different solvents on the fabrication process. Surface morphology, crystalline phase composition, and plasmon resonance of the coated samples were characterized by scanning electron microscopy (SEM), X-ray diffractometer (XRD), and UV-Vis spectroscopy, respectively. Results demonstrated the synthesis of spherical self-assembled AuNPs using toluene (TOL) and isopropyl alcohol (IPA) for reducing and precursor solvents, respectively. Changing the concentration of reactants or increasing the coating layers exhibited a change in the average size of AuNPs. Self-assembled AuNPs thin films were also demonstrated to have the potential to be used as a biosensing platform based on localized surface plasmon resonance (LSPR) effect to detect the elevated levels of glucose in an aqueous solution. Recently, the world has faced a pandemic of Covid-19 caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which has threatened human health and has brought a worldwide devastating economic and social crisis. Hence, finding a solution to mitigate the current breakout of Covid-19 is vital to protect the international community from its causing harm. AgNPs as an antimicrobial agent, which has exhibited promising antiviral activity against several viruses, can offer a resolution to combat the spread of Covid-19. In this regard, AgNPs thin films were fabricated analogously via blade coating using various reducer and silver salt inks made of different solvent systems. Virucidal efficacy of reactive blade coated AgNPs on glass substrates was analyzed against human coronavirus 229E, a virus from the Coronavirus family, as a surrogate SARS-CoV-2 (according to the Level 2 Biosafety facility at uOttawa). Plaque forming assay indicated more than 99.99% reduction in infectivity of the virus when it contacts the AgNPs coated glass for 30 min before infecting cells. These results suggest the excellent potential for reactive blade coated AgNPs as an antiviral agent against coronavirus to avoid the spread of the virus.
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Characterization of virus-host interactions using cellular thermal shift assays (CETSA)Lissner, Robin January 2021 (has links)
No description available.
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Mesenchymal Stem/Stromal Cells as a Therapeutic Intervention for COVID-19: A Living Systematic Review and Meta-AnalysisKirkham, Aidan 24 June 2022 (has links)
Background: Since its emergence in December 2019, SARS-CoV-2, the coronavirus
responsible for COVID-19, has spread across the globe, infected millions of people and caused several million deaths. One promising intervention to combat the ongoing COVID-19 pandemic is mesenchymal stem/stromal cells (MSCs). Many trials were registered at the onset of the pandemic to determine the safety and efficacy of MSCs in COVID-19 patients. However, currently published studies are underpowered to provide an estimate of safety and efficacy on their own. Thus, a living systematic review (SR) is needed to establish the benefits and drawbacks of MSCs for COVID-19 on a relevant timescale. Methods: Systematic literature searches were conducted on Feb 3rd, 2021 and November 15th, 2021 to identify all English-language, full-text, clinical studies examining MSCs to treat COVID-19. (PROSPERO:CRD42021225431). Findings/Conclusions: Our first search identified nine studies (4 controlled) examining the use of MSC derived products to treat COVID-19 patients. This first iteration of our SR revealed that MSCs were safe and reduced mortality in patients suffering from COVID-19. However, risk of bias (RoB) and poor adherence to ISCT cell product characterization guidelines limited the
strength of our conclusions. In the second iteration of our living SR, we only included controlled studies to strengthen our conclusions. We identified eleven controlled studies (5 RCTs). MSCs continued to demonstrate safety and efficacy at reducing mortality at study endpoint (RR: 0.50 [0.34 to 0.75, 95% CI, p=0.0006, I2=0%]). However, we continued to encounter barriers which prevented us from drawing more definitive conclusions. A master protocol appears necessary to facilitate the accelerated accumulation of high-quality evidence where standardized outcome
reporting and consistent product characterization allow for a more definitive and timely estimate regarding the safety and efficacy of this cell-based therapy for COVID-19.
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A RAPID PAPER-BASED COLORIMETRIC MOLECULAR TEST FOR SARS-COV-2 POINT-OF-CARE DIAGNOSTICJiangshan Wang (10725807) 29 April 2021 (has links)
<p>In the year of 2020, an
international pandemic caused by severe acute respiratory syndrome coronavirus
2 (SARS-CoV-2) has afflicted tens of millions of people’s life also disrupting global
economics. Diagnostic testing is an important part of ensuring public health
until a vaccine that has been shown to be safe and effective is made available
to the general public. Most tests for detecting COVID-19 utilize quantitative
polymerase chain reaction (qPCR) assays, which is a specific and relatively
simple quantitative assay that could provide adequate sensitivity for
diagnosing early infection. Although powerful, these lab-based molecular assays
have a significant lag time, usually several days before receiving results. To
satisfy the needs of different purposes (diagnostics, screening, and
surveillance),
a unified approach is impractical. This thesis presents an alternative testing
method supporting the current procedure of point of care (POC) testing and in
community testing. This paper-based test overcomes the limitations of current
testing methods by utilizing reverse-transcription loop-mediated isothermal amplification
(RT-LAMP) and receiving the result on-site by a color change in the presence of
the virus within 60 minutes. The test utilizes untreated freshly collected
saliva, a less invasive specimen, as the sample and possesses a limit of
detection (LoD) of 200 copies of virus per microliter of whole saliva with an analytical
sensitivity of 97% and analytical specificity of 100%. The test requires
minimal operator training and could be fabricated on a large-scale using
roll-to-roll methods. Since the test is based on nucleic acids, the testing
platform itself lends to further applications <a>including
food safety monitoring, animal diagnostic, etc. simply by changing the specific
primers</a>. </p>
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