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1.
Diabetes research and clinical practice ; 186:109260-109260, 2022.
Article in English | EuropePMC | ID: covidwho-1877385
2.
Embase; 2021.
Preprint in English | EMBASE | ID: ppcovidwho-334672

ABSTRACT

Based on its predicted ability to affect transmissibility and pathogenesis, surveillance studies have highlighted the role of a specific mutation (P681R) in the S1/S2 furin cleavage site of the SARS-CoV-2 spike protein. Here we analyzed A.23.1, first identified in Uganda, as a P681R-containing virus several months prior to the emergence of B.1.617.2 (Delta variant). We performed assays using peptides mimicking the S1/S2 from A.23.1 and B.1.617 and observed significantly increased cleavability with furin compared to both an original B lineage (Wuhan-Hu1) and B.1.1.7 (Alpha variant). We also performed cell-cell fusion and functional infectivity assays using pseudotyped particles and observed an increase in activity for A.23.1 compared to an original B lineage spike. However, these changes in activity were not reproduced in the B lineage spike bearing only the P681R substitution. Our findings suggest that while A.23.1 has increased furin-mediated cleavage linked to the P681R substitution, this substitution needs to occur on the background of other spike protein changes to enable its functional consequences.

3.
PubMed; 2021.
Preprint in English | PubMed | ID: ppcovidwho-333831

ABSTRACT

BACKGROUND: Heparin, in addition to its anticoagulant properties, has anti-inflammatory and potential anti-viral effects, and may improve endothelial function in patients with Covid-19. Early initiation of therapeutic heparin could decrease the thrombo-inflammatory process, and reduce the risk of critical illness or death. METHODS: We randomly assigned moderately ill hospitalized ward patients admitted for Covid-19 with elevated D-dimer level to therapeutic or prophylactic heparin. The primary outcome was a composite of death, invasive mechanical ventilation, non-invasive mechanical ventilation or ICU admission. Safety outcomes included major bleeding. Analysis was by intention-to-treat. RESULTS: At 28 days, the primary composite outcome occurred in 37 of 228 patients (16.2%) assigned to therapeutic heparin, and 52 of 237 patients (21.9%) assigned to prophylactic heparin (odds ratio, 0.69;95% confidence interval [CI], 0.43 to 1.10;p=0.12). Four patients (1.8%) assigned to therapeutic heparin died compared with 18 patients (7.6%) assigned to prophylactic heparin (odds ratio, 0.22;95%-CI, 0.07 to 0.65). The composite of all-cause mortality or any mechanical ventilation occurred in 23 (10.1%) in the therapeutic heparin group and 38 (16.0%) in the prophylactic heparin group (odds ratio, 0.59;95%-CI, 0.34 to 1.02). Major bleeding occurred in 2 patients (0.9%) with therapeutic heparin and 4 patients (1.7%) with prophylactic heparin (odds ratio, 0.52;95%-CI, 0.09 to 2.85). CONCLUSIONS: In moderately ill ward patients with Covid-19 and elevated D-dimer level, therapeutic heparin did not significantly reduce the primary outcome but decreased the odds of death at 28 days. Trial registration numbers: NCT04362085 ;NCT04444700.

4.
PubMed; 2022.
Preprint in English | PubMed | ID: ppcovidwho-332396

ABSTRACT

The African continent like all other parts of the world with high infection/low vaccination rates can, and will, be a source of novel SARS-CoV-2 variants. The A.23 viral lineage, characterized by three spike mutations F157L, V367F and Q613H, was first identified in COVID-19 cases from a Ugandan prison in July 2020, and then was identified in the general population with additional spike mutations (R102I, L141F, E484K and P681R) to comprise lineage A.23.1 by September 2020, with this virus being designated a variant of interest (VOI) in Africa and with subsequent spread to 26 other countries. The P681R spike substitution of the A.23.1 VOI is of note as it increases the number of basic residues in the sub-optimal SARS-CoV-2 spike protein furin cleavage site;as such, this substitution may affect viral replication, transmissibility or pathogenic properties. The same P681R substitution has also appeared in B.1.617 variants, including B.1.617.2 (Delta). Here, we performed assays using fluorogenic peptides mimicking the S1/S2 sequence from A.23.1 and B.1.617.2 and observed significantly increased cleavability with furin, compared to sequences derived from the original Wuhan-Hu1 S1/S2. We performed functional infectivity assays using pseudotyped MLV particles harboring SARS-CoV-2 spike proteins and observed an increase in transduction for A.23.1-pseudotyped particles compared to Wuhan-Hu-1 in Vero-TMPRSS2 and Calu-3 cells (with a presumed early entry pathway), although lowered infection in Vero E6 cells (with a presumed late entry pathway). However, these changes in infectivity were not reproduced in the original Wuhan-Hu-1 spike bearing only the P681R substitution. Our findings suggest that while A.23.1 has increased furin-mediated cleavage linked to the P681R substitution, which may affect viral infection and transmissibility, this substitution alone is not sufficient and needs to occur on the background of other spike protein changes to enable its full functional consequences.

5.
EuropePMC; 2021.
Preprint in English | EuropePMC | ID: ppcovidwho-294726

ABSTRACT

Objectives To assess the effectiveness of prone positioning to reduce the risk of death or respiratory failure in non-critically ill patients hospitalized with COVID-19 Design Pragmatic randomized clinical trial of prone positioning of patients hospitalized with COVID-19 across 15 hospitals in Canada and the United States from May 2020 until May 2021. Settings Patients were eligible is they had a laboratory-confirmed or a clinically highly suspected diagnosis of COVID-19, required supplemental oxygen (up to 50% fraction of inspired oxygen [FiO2]), and were able to independently prone with verbal instruction. ( NCT04383613 ). Main Outcome Measures The primary outcome was a composite of in-hospital death, mechanical ventilation, or worsening respiratory failure defined as requiring at least 60% FiO2 for at least 24 hours. Secondary outcomes included the change in the ratio of oxygen saturation to FiO2 (S/F ratio). Results A total of 248 patients were included. The trial was stopped early on the basis of futility for the pre-specified primary outcome. The median time from hospital admission until randomization was 1 day, the median age of patients was 56 years (interquartile range [IQR] 45,65), 36% were female, and 90% of patients were receiving oxygen via nasal prongs at the time of randomization. The median time spent prone in the first 72 hours was 6 hours total (IQR 1.5,12.8) for the prone arm compared to 0 hours (0,2) in the control arm. The risk of the primary outcome was similar between the prone group (18 [14.3%] events) and the standard care group (17 [13.9%] events), odds ratio 0.92 (95% CI 0.44 to 1.92). The change in the S/F ratio after 72 hours was similar for patients randomized to prone compared to standard of care. Conclusion Among hypoxic but not critically patients with COVID-19 in hospital, a multifaceted intervention to increase prone positioning did not improve outcomes. Adherence to prone positioning was poor, despite multiple efforts. Subsequent trials of prone positioning should aim to develop strategies to improve adherence to awake prone positioning. What is already known on this topic Prone positioning is considered standard of care for mechanically ventilated patients who have severe acute respiratory distress syndrome. Recent data suggest prone positioning is beneficial for patients with COVID-19 who are requiring high flow oxygen. It is unknown of prone positioning is beneficial for patients not on high flow oxygen. What this study adds Prone positioning is generally not well tolerated and innovative approaches are needed to improve adherence. Clinical and physiologic outcomes were not improved with prone positioning among hypoxic but not critically ill patients hospitalized with COVID-19.

6.
PUBMED; 2021.
Preprint in English | PUBMED | ID: ppcovidwho-293019

ABSTRACT

The African continent like all other parts of the world with high infection/low vaccination rates can, and will, be a source of novel SARS-CoV-2 variants. The A.23 viral lineage, characterized by three spike mutations F157L, V367F and Q613H, was first identified in COVID-19 cases from a Ugandan prison in July 2020, and then was identified in the general population with the additional spike mutation P681R at the S1/S2 cleavage site to comprise lineage A.23.1 by September 2020 with subsequent spread to 26 other countries. The P681R spike substitution of A.23.1 is of note as it increases the number of basic residues in the sub-optimal SARS-CoV-2 spike protein furin cleavage site;as such, this substitution may affect viral replication, transmissibility, or pathogenic properties. The same P681R substitution has also subsequently appeared in B.1.617 variants, including B.1.617.2 (Delta). Here, we performed assays using fluorogenic peptides mimicking the S1/S2 from A.23.1 and B.1.617 and observed significantly increased cleavability with furin, compared to sequences derived from the original Wuhan-Hu1 S1/S2. We performed cell-cell fusion and functional infectivity assays using pseudotyped particles harboring SARS-CoV-2 spike proteins and observed an increase in transduction for A.23.1-pseudotyped particles compared to Wuhan-Hu-1. However, these changes in activity were not reproduced in the original Wuhan-Hu-1 spike bearing only the P681R substitution. Our findings suggest that while A.23.1 has increased furin-mediated cleavage linked to the P681R substitution-which may affect viral infection and transmissibility-this substitution alone needs to occur on the background of other spike protein changes to enable its full functional consequences. Graphical abstract:

7.
Emerging Trends in Global Organizational Science Phenomena: Critical Roles of Politics, Leadership, Stress, and Context ; : 149-170, 2021.
Article in English | Scopus | ID: covidwho-1469295

ABSTRACT

Monetary wisdom asserts that decision-makers select their deep-rooted personal values as a lens and frame the critical concerns in the proximal-immediate and distal-omnibus contexts to maximize their expected utilities and ultimate serenity. In the Holy Bible, Jesus talked about the Parable of Talents in the book of Matthew. "A man who was going on a journey called in his servants and entrusted his possessions to them. To one he gave five talents;to another, two;to a third, one-to each according to his ability." These three servants' handling of the entrusted possessions tells us an exciting story of the Matthew Effect, their values toward the money, and their Monetary Wisdom. The Matthew Effect has bright and dark sides. The rich get richer, and the poor get poorer. I summarize my journey from the Matthew Effect, the love of money, serving God and mammon, to the development of Monetary Wisdom-a global theory of organization science. For decades, scholars have substantiated this psychological construct in 45 countries across six continents. Avaricious monetary aspiration predicts not only behavioral intentions but also actions. This theory applies to decision-makers at the individual, group, organization, country, global levels, and stressful COVID-19 pandemic. Serving God leads to growth and prosperity. Serving mammon leads to death and poverty. Monetary Wisdom sparks our interest in the Holy Bible and behavioral economics, helping us become healthier, happier, and wealthier than before. © 2021 Nova Science Publishers, Inc.

8.
PLoS ONE ; 16(2), 2021.
Article in English | CAB Abstracts | ID: covidwho-1410574

ABSTRACT

Public health measures to reduce COVID-19 transmission include masking in public places, physical distancing, staying home when ill, avoiding high-risk locations, using a contact tracing app, and being willing to take a COVID-19 vaccine. However, adoption of these measures varies greatly. We aimed to improve health messaging to increase adherence to public health behaviours to reduce COVID-19 transmission by: (1) determining attitudes towards public health measures and current behaviours;(2) identifying barriers to following public health measures;and, (3) identifying public health communication strategies. We recruited participants from a random panel of 3000 phone numbers across Alberta to fill a predetermined quota: age (18-29;30-59;60+ years), geographic location (urban;rural), and whether they had school-age children. Two researchers coded and themed all transcripts. We performed content analysis and in-depth thematic analysis. Nine focus groups were conducted with 2-8 participants/group in August-September, 2020. Several themes were identified: (1) importance of public health measures;(2) compliance with public health measures;(3) critiques of public health messaging;and (4) suggestions for improving public health messaging. Physical distancing and masking were seen as more important than using a contact tracing app. There were mixed views around willingness to take COVID-19 vaccine. Current public health messaging was perceived as conflicting. Participants felt that consistent messaging and using social media to reach younger people would be helpful. In conclusion, these findings provide insights that can be used to inform targeted (e.g., by age, current behaviour) public health communications to encourage behaviors that reduce COVID-19 transmission.

9.
Applied Catalysis B: Environmental ; 298, 2021.
Article in English | Scopus | ID: covidwho-1330633

ABSTRACT

With the worldwide pandemic of COVID-19, a tremendous amount of face masks have been consumed and discarded, resulting in serious environment pollution and infectious hazards. Herein a green and high-yield route has been developed to recycle waste masks (WMs) into CNTs/Ni hybrids via catalytic carbonization. Our results exhibited that the yield of carbon was as high as 64.4 g/100 g WMs. Furthermore, the as-fabricated CNTs/Ni hybrids were applied for microwave absorption, which displayed superior performances, including a strong reflection loss of -56.3 dB and an absorption bandwidth of 4.3 GHz with absorber thickness of only 2.0 mm. The mechanism was mainly ascribed to the favorable synergistic effects of CNTs and Ni on conduction and magnetic losses, dipolar polarization, interfacial polarization and impedance matching. Thus, this work provides an environmentally friendly, scalable and cost-effective strategy for recycling waste masks into high-valuable carbon nanomaterials, and exploits their potential application for microwave absorption. © 2021 Elsevier B.V.

10.
Journal of Business and Industrial Marketing ; 2021.
Article in English | Scopus | ID: covidwho-1276345

ABSTRACT

Purpose: In an ongoing War for Talent, what are the intangible and tangible return on investments (ROIs) for boundary-spanning employees? This study aims to develop a formative structural equation model (SEM) of the Matthew effect in talent. management. Design/methodology/approach: This study develops a formative SEM theoretical model. Training and development (T&D) are the two antecedents of the latent construct – talent management strategy (TMS). This study frames the latent construct (TMS) in the proximal context of reducing burnout (cynicism and inefficacy), the distal context of subjective and intangible outcomes (job and life satisfaction) and the omnibus context of objective, tangible and financial rewards (the sales commission). The study collected data from multiple sources – objective sales commission from personnel records and subjective survey data from 512 sales employees. Findings: The empirical discoveries support the theory. Both T&D contribute significantly to the TMS, which reduces burnout in the immediate context. TMS enhances job satisfaction more than life satisfaction in the distal context. TMS significantly and indirectly improves boundary spanners’ sales commission in the omnibus context via life satisfaction, but not job satisfaction. The model prevails for the whole sample, men, but not women. Practical implications: Our discoveries offer practical implications for the Matthew effect in talent management: policymakers must cultivate T&D, develop TMS, facilitate the spillover effect from job satisfaction to life satisfaction, concentrate on the meaning in their lives and take their mind off money. TMS ultimately helps ignite these boundary spanners’ sales commission and their organization’s bottom line and financial health. The rich get richer. Originality/value: It is life satisfaction (not job satisfaction) that excites boundary-spanning employees’ high level of sales commission. Our model prevails for the whole sample and men, but not for women. Job satisfaction spills over to life satisfaction for the entire sample, for men, but not for women. The results reveal gender differences. © 2021, Emerald Publishing Limited.

11.
Complex Systems and Complexity Science ; 18(1):53-62, 2021.
Article in Chinese | Scopus | ID: covidwho-1069995

ABSTRACT

The outbreak of COVID-19 has turned many areas into disaster areas. In order to provide timely relief to the disaster areas, accurate supply of post-disaster emergency resources has become the primary factor to ensure the safety of the people in the disaster areas. In this paper, SEIR was used to predict the number of infected people in each disaster area at the decision-making moment, and then the weight of urgency degree and material demand in the disaster area were calculated. Based on the degree of urgency, a multi-objective optimization model of emergency resource scheduling was constructed to maximize the satisfaction of the victims, minimize the total cost and consider the fairness of distribution. A multi-objective artificial bee colony algorithm is proposed. Aiming at the disadvantages of artificial bee colony algorithm such as precocity, the dynamic parameter and Pareto solution set are used to define the new bee colony location updating formula, and the teaching optimization is used to disturb the bee colony location, so as to avoid the algorithm falling into local extremum. The simulation results show that the proposed model and algorithm can effectively solve the problem of optimal allocation of emergency resources at multiple disaster points under epidemic events, and the improved algorithm has better performance. © 2021, The Editorial Department of Complex Systems and Complexity Science. All right reserved.

12.
Journal of Transportation Safety and Security ; 2021.
Article in English | Scopus | ID: covidwho-1057790

ABSTRACT

The virus 2019-nCoV rapidly crossed the globe in the first quarter of 2020, and the global civil aviation industry contributed to the spread of the virus. The aircraft deplaning process is one of the critical stages of the spread of infectious diseases and merits careful research accordingly. However, little effort has been made to tailor the civil aircraft deplaning process to the existence of patients with severe acute airborne disease. In this study, we explore a mixed patient-health pedestrian deplaning flow from a Boeing 737-300’s with a full economy-class layout as per the virus spread dynamics during the process. We develop feasible deplaning management strategies that can reduce the inflection risk to the healthy passengers during the deplaning process. We then quantitatively compare the deplaning process before and after adopting the proposed strategies. The numerical results show that the proposed strategies effectively reduce the risk of infection during the deplaning process but sacrifice deplaning efficiency. We assert that health outweighs efficiency, and find that the proposed strategy may thus have practical value and potentially be of use to administrators. © 2021 Taylor & Francis Group, LLC and The University of Tennessee.

14.
Eur Rev Med Pharmacol Sci ; 24(12): 7164-7172, 2020 06.
Article in English | MEDLINE | ID: covidwho-723470

ABSTRACT

Chloroquine, a 4-aminoquinoline derivative, was initially used to treat malaria. It was later found to have immunomodulating, anti-infective, anti-thrombotic, anti-tumor, and metabolic effects. Recently, many studies have focused on the application of chloroquine in viral infections. Most in vitro studies suggested that chloroquine exerted some benefit in infections from viruses. However, animal experiment and clinical trials that attempted to use chloroquine in prevention or treatment of viral infections have reported disappointing results. It might be attributable to inadequate steady-state whole blood chloroquine concentration necessary for exerting its antiviral effects. A 16 µM/L steady-state whole blood concentration of chloroquine should suffice in antiviral treatment with minimal toxicity. Furthermore, chloroquine has both acute and cumulative toxicity. Hence, not only the appropriate treatment dose is crucial, the occurrence of adverse reactions should also be closely monitored and treated in time. Herein, we report the antiviral mechanisms, effects, safety and adverse effects of chloroquine.


Subject(s)
Antiviral Agents/adverse effects , Antiviral Agents/pharmacology , Chloroquine/adverse effects , Chloroquine/pharmacology , Viruses/drug effects , Animals , Antiviral Agents/metabolism , Chloroquine/metabolism , Humans
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