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1.
Journal of Retailing and Consumer Services ; 74:103426, 2023.
Article in English | ScienceDirect | ID: covidwho-20231357

ABSTRACT

While the customer-to-manufacturer (C2M) business model has received increasing attention as a new business model for e-commerce and retail industry, little is still known about it and the effect of its approach. This study aims to understand how brand-related stimuli in C2M environments affect customer responses as the worldwide COVID-19 pandemic. The outcomes reveal that the Sensory, affective, and intellectual aspects of brand experience positively influence brand authenticity. Brand authenticity has a positive effect on behavioral intention, such as reuse intention and word-of-mouth. Additionally, this research finds that social presence moderates the association between the sensory aspect of brand experience. Thus, this study can suggest a C2M business model as a means of sustainable operation of the retail industry to both researchers and practitioners in relation to the retail industry.

2.
Open Learning: The Journal of Open and Distance Learning ; : No Pagination Specified, 2022.
Article in English | APA PsycInfo | ID: covidwho-2286998

ABSTRACT

ABSTRACT Drawing upon 15 semi-structured interviews with teachers at a Catholic school in the British city of Hull, we offer new qualitative insights on the effects of students' unequal access to digital tools when switching to distance learning in the context of COVID-19 school closures. During the 2020-2021 academic year, this school serving pupils from highly dissimilar socioeconomic backgrounds distributed 300 laptops to students who did not own any digital learning device. It emerges that students with limited access to devices suffered negative impacts on their academic performance, and that this effect also applied to students who had access to a mobile device and hence did not receive a laptop. Our interviews also suggest that having to share a device with another family member leads to more absenteeism and a fall in academic attainment. Low parental involvement is shown to have negative effects on students' attainment, particularly for children from deprived backgrounds. Finally, poorer students are seen to become isolated from peers, with diminishing social skills throughout lockdowns due to their lack of access to digital tools. (PsycInfo Database Record (c) 2022 APA, all rights reserved)

3.
Open Learning ; : 1-15, 2022.
Article in English | Academic Search Complete | ID: covidwho-2134093

ABSTRACT

Drawing upon 15 semi-structured interviews with teachers at a Catholic school in the British city of Hull, we offer new qualitative insights on the effects of students’ unequal access to digital tools when switching to distance learning in the context of COVID-19 school closures. During the 2020–2021 academic year, this school serving pupils from highly dissimilar socioeconomic backgrounds distributed 300 laptops to students who did not own any digital learning device. It emerges that students with limited access to devices suffered negative impacts on their academic performance, and that this effect also applied to students who had access to a mobile device and hence did not receive a laptop. Our interviews also suggest that having to share a device with another family member leads to more absenteeism and a fall in academic attainment. Low parental involvement is shown to have negative effects on students’ attainment, particularly for children from deprived backgrounds. Finally, poorer students are seen to become isolated from peers, with diminishing social skills throughout lockdowns due to their lack of access to digital tools. [ FROM AUTHOR]

4.
Psychiatry Investig ; 19(11): 919-926, 2022 Nov.
Article in English | MEDLINE | ID: covidwho-2146316

ABSTRACT

OBJECTIVE: We aimed to determine the effects of depression, COVID-19 infection fear, and resilience on COVID-19-related functional impairment. METHODS: We obtained data from 476 community-dwelling adults aged 20-69 years living in Jeju, South Korea, and evaluated the relationships between COVID-19-related functional impairment (work/school, social, and home life) and sociodemographic and healthrelated characteristics, COVID-19-related life changes (financial difficulties since the pandemic, employment change, interpersonal conflict), and clinical characteristics, including depression, COVID-19 infection fear, and resilience. RESULTS: Functional impairment in the home life domain was associated with marital status and monthly income. Greater work/school, social, and home life functional impairment was significantly associated with all COVID-19-related life changes. Regression analysis indicated that resilience modulated the positive associations of COVID-19-related functional impairment with symptoms of depression and COVID-19 infection fear when relevant factors were controlled for. CONCLUSION: Our results suggest the importance of clinical characteristics, including depression, COVID-19 infection fear, and resilience for understanding functional impairment related to COVID-19. These results have important implications for interventions aimed at reducing depression and COVID-19 infection fear, and enhancing resilience.

5.
Cochrane Database Syst Rev ; 8: CD015021, 2022 08 09.
Article in English | MEDLINE | ID: covidwho-1981526

ABSTRACT

BACKGROUND: High efficacy in terms of protection from severe COVID-19 has been demonstrated for several SARS-CoV-2 vaccines. However, patients with compromised immune status develop a weaker and less stable immune response to vaccination. Strong immune response may not always translate into clinical benefit, therefore it is important to synthesise evidence on modified schemes and types of vaccination in these population subgroups for guiding health decisions. As the literature on COVID-19 vaccines continues to expand, we aimed to scope the literature on multiple subgroups to subsequently decide on the most relevant research questions to be answered by systematic reviews. OBJECTIVES: To provide an overview of the availability of existing literature on immune response and long-term clinical outcomes after COVID-19 vaccination, and to map this evidence according to the examined populations, specific vaccines, immunity parameters, and their way of determining relevant long-term outcomes and the availability of mapping between immune reactivity and relevant outcomes. SEARCH METHODS: We searched the Cochrane COVID-19 Study Register, the Web of Science Core Collection, and the World Health Organization COVID-19 Global literature on coronavirus disease on 6 December 2021.  SELECTION CRITERIA: We included studies that published results on immunity outcomes after vaccination with BNT162b2, mRNA-1273, AZD1222, Ad26.COV2.S, Sputnik V or Sputnik Light, BBIBP-CorV, or CoronaVac on predefined vulnerable subgroups such as people with malignancies, transplant recipients, people undergoing renal replacement therapy, and people with immune disorders, as well as pregnant and breastfeeding women, and children. We included studies if they had at least 100 participants (not considering healthy control groups); we excluded case studies and case series. DATA COLLECTION AND ANALYSIS: We extracted data independently and in duplicate onto an online data extraction form. Data were represented as tables and as online maps to show the frequency of studies for each item. We mapped the data according to study design, country of participant origin, patient comorbidity subgroup, intervention, outcome domains (clinical, safety, immunogenicity), and outcomes.  MAIN RESULTS: Out of 25,452 identified records, 318 studies with a total of more than 5 million participants met our eligibility criteria and were included in the review. Participants were recruited mainly from high-income countries between January 2020 and 31 October 2021 (282/318); the majority of studies included adult participants (297/318).  Haematological malignancies were the most commonly examined comorbidity group (N = 54), followed by solid tumours (N = 47), dialysis (N = 48), kidney transplant (N = 43), and rheumatic diseases (N = 28, 17, and 15 for mixed diseases, multiple sclerosis, and inflammatory bowel disease, respectively). Thirty-one studies included pregnant or breastfeeding women. The most commonly administered vaccine was BNT162b2 (N = 283), followed by mRNA-1273 (N = 153), AZD1222 (N = 66), Ad26.COV2.S (N = 42), BBIBP-CorV (N = 15), CoronaVac (N = 14), and Sputnik V (N = 5; no studies were identified for Sputnik Light). Most studies reported outcomes after regular vaccination scheme.  The majority of studies focused on immunogenicity outcomes, especially seroconversion based on binding antibody measurements and immunoglobulin G (IgG) titres (N = 179 and 175, respectively). Adverse events and serious adverse events were reported in 126 and 54 studies, whilst SARS-CoV-2 infection irrespective of severity was reported in 80 studies. Mortality due to SARS-CoV-2 infection was reported in 36 studies. Please refer to our evidence gap maps for more detailed information. AUTHORS' CONCLUSIONS: Up to 6 December 2021, the majority of studies examined data on mRNA vaccines administered as standard vaccination schemes (two doses approximately four to eight weeks apart) that report on immunogenicity parameters or adverse events. Clinical outcomes were less commonly reported, and if so, were often reported as a secondary outcome observed in seroconversion or immunoglobulin titre studies. As informed by this scoping review, two effectiveness reviews (on haematological malignancies and kidney transplant recipients) are currently being conducted.


Subject(s)
COVID-19 , Hematologic Neoplasms , Vaccines , Ad26COVS1 , Adult , BNT162 Vaccine , COVID-19/epidemiology , COVID-19/prevention & control , COVID-19 Vaccines , ChAdOx1 nCoV-19 , Child , Female , Humans , Pregnancy , SARS-CoV-2 , Vaccination
6.
Cochrane Database Syst Rev ; 6: CD014945, 2022 06 17.
Article in English | MEDLINE | ID: covidwho-1898513

ABSTRACT

BACKGROUND: Monoclonal antibodies (mAbs) are laboratory-produced molecules derived from the B cells of an infected host. They are being investigated as potential prophylaxis to prevent coronavirus disease 2019 (COVID-19). OBJECTIVES: To assess the effects of SARS-CoV-2-neutralising mAbs, including mAb fragments, to prevent infection with SARS-CoV-2 causing COVID-19; and to maintain the currency of the evidence, using a living systematic review approach. SEARCH METHODS: We searched the Cochrane COVID-19 Study Register, MEDLINE, Embase, and three other databases on 27 April 2022. We checked references, searched citations, and contacted study authors to identify additional studies. SELECTION CRITERIA: We included randomised controlled trials (RCTs) that evaluated SARS-CoV-2-neutralising mAbs, including mAb fragments, alone or combined, versus an active comparator, placebo, or no intervention, for pre-exposure prophylaxis (PrEP) and postexposure prophylaxis (PEP) of COVID-19. We excluded studies of SARS-CoV-2-neutralising mAbs to treat COVID-19, as these are part of another review. DATA COLLECTION AND ANALYSIS: Two review authors independently assessed search results, extracted data, and assessed risk of bias using Cochrane RoB 2. Prioritised outcomes were infection with SARS-CoV-2, development of clinical COVID-19 symptoms, all-cause mortality, admission to hospital, quality of life, adverse events (AEs), and serious adverse events (SAEs). We rated the certainty of evidence using GRADE. MAIN RESULTS: We included four RCTs of 9749 participants who were previously uninfected and unvaccinated at baseline. Median age was 42 to 76 years. Around 20% to 77.5% of participants in the PrEP studies and 35% to 100% in the PEP studies had at least one risk factor for severe COVID-19. At baseline, 72.8% to 82.2% were SARS-CoV-2 antibody seronegative. We identified four ongoing studies, and two studies awaiting classification. Pre-exposure prophylaxis Tixagevimab/cilgavimab versus placebo One study evaluated tixagevimab/cilgavimab versus placebo in participants exposed to SARS-CoV-2 wild-type, Alpha, Beta, and Delta variant. About 39.3% of participants were censored for efficacy due to unblinding and 13.8% due to vaccination. Within six months, tixagevimab/cilgavimab probably decreases infection with SARS-CoV-2 (risk ratio (RR) 0.45, 95% confidence interval (CI) 0.29 to 0.70; 4685 participants; moderate-certainty evidence), decreases development of clinical COVID-19 symptoms (RR 0.18, 95% CI 0.09 to 0.35; 5172 participants; high-certainty evidence), and may decrease admission to hospital (RR 0.03, 95% CI 0 to 0.59; 5197 participants; low-certainty evidence). Tixagevimab/cilgavimab may result in little to no difference on mortality within six months, all-grade AEs, and SAEs (low-certainty evidence). Quality of life was not reported. Casirivimab/imdevimab versus placebo One study evaluated casirivimab/imdevimab versus placebo in participants who may have been exposed to SARS-CoV-2 wild-type, Alpha, and Delta variant. About 36.5% of participants opted for SARS-CoV-2 vaccination and had a mean of 66.1 days between last dose of intervention and vaccination. Within six months, casirivimab/imdevimab may decrease infection with SARS-CoV-2 (RR 0.01, 95% CI 0 to 0.14; 825 seronegative participants; low-certainty evidence) and may decrease development of clinical COVID-19 symptoms (RR 0.02, 95% CI 0 to 0.27; 969 participants; low-certainty evidence). We are uncertain whether casirivimab/imdevimab affects mortality regardless of the SARS-CoV-2 antibody serostatus. Casirivimab/imdevimab may increase all-grade AEs slightly (RR 1.14, 95% CI 0.98 to 1.31; 969 participants; low-certainty evidence). The evidence is very uncertain about the effects on grade 3 to 4 AEs and SAEs within six months. Admission to hospital and quality of life were not reported. Postexposure prophylaxis Bamlanivimab versus placebo One study evaluated bamlanivimab versus placebo in participants who may have been exposed to SARS-CoV-2 wild-type. Bamlanivimab probably decreases infection with SARS-CoV-2 versus placebo by day 29 (RR 0.76, 95% CI 0.59 to 0.98; 966 participants; moderate-certainty evidence), may result in little to no difference on all-cause mortality by day 60 (R 0.83, 95% CI 0.25 to 2.70; 966 participants; low-certainty evidence), may increase all-grade AEs by week eight (RR 1.12, 95% CI 0.86 to 1.46; 966 participants; low-certainty evidence), and may increase slightly SAEs (RR 1.46, 95% CI 0.73 to 2.91; 966 participants; low-certainty evidence). Development of clinical COVID-19 symptoms, admission to hospital within 30 days, and quality of life were not reported. Casirivimab/imdevimab versus placebo One study evaluated casirivimab/imdevimab versus placebo in participants who may have been exposed to SARS-CoV-2 wild-type, Alpha, and potentially, but less likely to Delta variant. Within 30 days, casirivimab/imdevimab decreases infection with SARS-CoV-2 (RR 0.34, 95% CI 0.23 to 0.48; 1505 participants; high-certainty evidence), development of clinical COVID-19 symptoms (broad-term definition) (RR 0.19, 95% CI 0.10 to 0.35; 1505 participants; high-certainty evidence), may result in little to no difference on mortality (RR 3.00, 95% CI 0.12 to 73.43; 1505 participants; low-certainty evidence), and may result in little to no difference in admission to hospital. Casirivimab/imdevimab may slightly decrease grade 3 to 4 AEs (RR 0.50, 95% CI 0.24 to 1.02; 2617 participants; low-certainty evidence), decreases all-grade AEs (RR 0.70, 95% CI 0.61 to 0.80; 2617 participants; high-certainty evidence), and may result in little to no difference on SAEs in participants regardless of SARS-CoV-2 antibody serostatus. Quality of life was not reported. AUTHORS' CONCLUSIONS: For PrEP, there is a decrease in development of clinical COVID-19 symptoms (high certainty), infection with SARS-CoV-2 (moderate certainty), and admission to hospital (low certainty) with tixagevimab/cilgavimab. There is low certainty of a decrease in infection with SARS-CoV-2, and development of clinical COVID-19 symptoms; and a higher rate for all-grade AEs with casirivimab/imdevimab. For PEP, there is moderate certainty of a decrease in infection with SARS-CoV-2 and low certainty for a higher rate for all-grade AEs with bamlanivimab. There is high certainty of a decrease in infection with SARS-CoV-2, development of clinical COVID-19 symptoms, and a higher rate for all-grade AEs with casirivimab/imdevimab.   Although there is high-to-moderate certainty evidence for some outcomes, it is insufficient to draw meaningful conclusions. These findings only apply to people unvaccinated against COVID-19. They are only applicable to the variants prevailing during the study and not other variants (e.g. Omicron). In vitro, tixagevimab/cilgavimab is effective against Omicron, but there are no clinical data. Bamlanivimab and casirivimab/imdevimab are ineffective against Omicron in vitro. Further studies are needed and publication of four ongoing studies may resolve the uncertainties.


Subject(s)
Antineoplastic Agents, Immunological , COVID-19 , Adult , Aged , Antibodies, Monoclonal/adverse effects , Antibodies, Monoclonal, Humanized , Antibodies, Neutralizing , COVID-19/prevention & control , Humans , Middle Aged , SARS-CoV-2
7.
PLoS Pathog ; 18(4): e1010468, 2022 04.
Article in English | MEDLINE | ID: covidwho-1779781

ABSTRACT

An overreactive inflammatory response and coagulopathy are observed in patients with severe form of COVID-19. Since increased levels of D-dimer (DD) are associated with coagulopathy in COVID-19, we explored whether DD contributes to the aberrant cytokine responses. Here we show that treatment of healthy human monocytes with DD induced a dose dependent increase in production of pyrogenic mediator, Prostaglandin E2 (PGE2) and inflammatory cytokines, IL-6 and IL-8. The DD-induced PGE2 and inflammatory cytokines were enhanced significantly by co-treatment with immune complexes (IC) of SARS CoV-2 recombinant S protein or of pseudovirus containing SARS CoV-2 S protein (PVCoV-2) coated with spike-specific chimeric monoclonal antibody (MAb) containing mouse variable and human Fc regions. The production of PGE2 and cytokines in monocytes activated with DD and ICs was sensitive to the inhibitors of ß2 integrin and FcγRIIa, and to the inhibitors of calcium signaling, Mitogen-Activated Protein Kinase (MAPK) pathway, and tyrosine-protein kinase. Importantly, strong increase in PGE2 and in IL-6/IL-8/IL-1ß cytokines was observed in monocytes activated with DD in the presence of IC of PVCoV-2 coated with plasma from hospitalized COVID-19 patients but not from healthy donors. The IC of PVCoV-2 with convalescent plasma induced much lower levels of PGE2 and cytokines compared with plasma from hospitalized COVID-19 patients. PGE2 and IL-6/IL-8 cytokines produced in monocytes activated with plasma-containing IC, correlated well with the levels of spike binding antibodies and not with neutralizing antibody titers. Our study suggests that a combination of high levels of DD and high titers of spike-binding antibodies that can form IC with SARS CoV-2 viral particles might accelerate the inflammatory status of lung infiltrating monocytes leading to increased lung pathology in patients with severe form of COVID-19.


Subject(s)
COVID-19 , Monocytes , Animals , Antigen-Antibody Complex , COVID-19/therapy , Cytokines/metabolism , Dinoprostone/metabolism , Fibrin Fibrinogen Degradation Products , Humans , Immunization, Passive , Immunologic Factors/metabolism , Interleukin-6/metabolism , Interleukin-8/metabolism , Mice , Spike Glycoprotein, Coronavirus/metabolism , COVID-19 Serotherapy
8.
Int J Infect Dis ; 108: 428-434, 2021 Jul.
Article in English | MEDLINE | ID: covidwho-1364090

ABSTRACT

OBJECTIVE: To investigate the duration and peak of severe acute respiratory syndrome coronavirus 2 shedding as infectivity markers for determining the isolation period. METHODS: A total of 2,558 upper respiratory tract (URT) and lower respiratory tract (LRT) specimens from 138 patients with laboratory-confirmed coronavirus disease were analyzed. Measurements of sequential viral loads were aggregated using the cubic spline smoothing function of a generalized additive model. The time to negative conversion was compared between symptom groups using survival analysis. RESULTS: In URT samples, viral RNA levels peaked on day 4 after symptom onset and rapidly decreased until day 10 for both E and RdRp genes, whereas those in LRT samples immediately peaked from symptom onset and decreased until days 15.6 and 15.0 for E and RdRp genes, respectively. Median (interquartile range) time to negative conversion was significantly longer in symptomatic (18.0 [13.0-25.0] days) patients than in asymptomatic (13.0 [9.5-17.5] days) patients. The more types of symptoms a patient had, the longer the time to negative conversion. CONCLUSIONS: The viral load rapidly changes depending on the time after symptom onset; the viral shedding period may be longer with more clinical symptoms. Different isolation policies should be applied depending on disease severity.


Subject(s)
COVID-19 , Humans , RNA, Viral , Republic of Korea , Respiratory System , SARS-CoV-2 , Viral Load , Virus Shedding
9.
Arch Med Sci Atheroscler Dis ; 6: e30-e39, 2021.
Article in English | MEDLINE | ID: covidwho-1241324

ABSTRACT

INTRODUCTION: The world is currently facing the pandemic of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The total number of cases of coronavirus disease 2019 (COVID-19) is rising daily and no vaccine has yet been approved. While the pathophysiology behind the virus is still being studied, many possible several risk factors using small sample sizes have been found. MATERIAL AND METHODS: We conducted a pooled analysis using several databases such as Medline, Scopus, Wangfang, Web of Science, Research Square, medrxiv, and Google Scholar to identify studies reporting severe and non-severe groups of COVID-19 patients. The odds ratios as well as the 95% confidence intervals for hypertension, diabetes, and cerebrovascular disease leading to severe COVID-19 were calculated using R-software. RESULTS: Fifty-three articles were used for our analysis and they involved 30,935 confirmed cases of COVID-19 from several countries across the world. The odds ratio for severe COVID-19 in hypertensive patients, diabetics, and patients with a history of cerebrovascular disease was 2.58 (95% confidence interval (CI): 2.16-3.08, from 53 studies), 2.17 (95% CI: 1.72-2.74, from 44 studies), and 2.63 (95% CI: 1.80-3.85, from 25 studies), respectively. CONCLUSIONS: Our analysis confirms that patients with hypertension, diabetes, or cerebrovascular disease are at a higher risk of a severe outcome of COVID-19. It is thus vital for physicians to identify the main risk factors for a severe outcome of this disease.

10.
Arch Med Sci Atheroscler Dis ; 6: e5-e13, 2021.
Article in English | MEDLINE | ID: covidwho-1241323

ABSTRACT

It has been more than a year since the new virus called severe acute respiratory syndrome Coronavirus 2 (SARS-CoV-2) was identified in Wuhan, China. The disease it causes was named Coronavirus disease 2019 (COVID-19), and on 11 March 2020 it was declared a pandemic. As the virus continues to spread, the number of patients worldwide has already crossed the 100 million mark with more than 2 million deaths. We sought to provide an update on the progress made in identifying the virus, its pathophysiology, risk factors such as hypertension, diabetes, and smoking, as well as various methods of treatment. Our review also provided an overview of the different vaccines.

11.
Antiviral Res ; 184: 104955, 2020 12.
Article in English | MEDLINE | ID: covidwho-871719

ABSTRACT

Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), is considered as the most significant global public health crisis of the century. Several drug candidates have been suggested as potential therapeutic options for COVID-19, including remdesivir, currently the only authorized drug for use under an Emergency Use Authorization. However, there is only limited information regarding the safety profiles of the proposed drugs, in particular drug-induced cardiotoxicity. Here, we evaluated the antiviral activity and cardiotoxicity of remdesivir using cardiomyocytes-derived from human pluripotent stem cells (hPSC-CMs) as an alternative source of human primary cardiomyocytes (CMs). In this study, remdesivir exhibited up to 60-fold higher antiviral activity in hPSC-CMs compared to Vero E6 cells; however, it also induced moderate cardiotoxicity in these cells. To gain further insight into the drug-induced arrhythmogenic risk, we assessed QT interval prolongation and automaticity of remdesivir-treated hPSC-CMs using a multielectrode array (MEA). As a result, the data indicated a potential risk of QT prolongation when remdesivir is used at concentrations higher than the estimated peak plasma concentration. Therefore, we conclude that close monitoring of the electrocardiographic/QT interval should be advised in SARS-CoV-2-infected patients under remdesivir medication, in particular individuals with pre-existing heart conditions.


Subject(s)
Adenosine Monophosphate/analogs & derivatives , Alanine/analogs & derivatives , Antiviral Agents/pharmacology , COVID-19/virology , Myocytes, Cardiac/virology , Pluripotent Stem Cells/cytology , SARS-CoV-2/drug effects , Adenosine Monophosphate/pharmacology , Alanine/pharmacology , Amides/pharmacology , Animals , Antimalarials/pharmacology , COVID-19/complications , Chlorocebus aethiops , Chloroquine/pharmacology , Electrocardiography , Flow Cytometry , Heart Diseases/complications , Humans , Hydroxychloroquine/pharmacology , Microscopy, Fluorescence , Myocytes, Cardiac/drug effects , Pluripotent Stem Cells/virology , Pyrazines/pharmacology , Real-Time Polymerase Chain Reaction , Reverse Transcriptase Polymerase Chain Reaction , Vero Cells , Viral Plaque Assay , COVID-19 Drug Treatment
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